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APPLICATION GUIDE

Die & Mould Making

CONTENTSIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Die construction work flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Die and mould material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Cast-iron . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6From quotation to a finished press tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Process planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18The right choice of highly productive cutting tools for roughing to finishing . . . . . . . . . . 20The versatility of round inserts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Application technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Sculptured surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Pitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Entrance and exit of cut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Ramping and circular interpolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38Choice of holding tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Extended tools in roughing of a cavity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Machining in segments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Methods for machining of corners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Methods for machining of a cavity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50HSM-High speed machining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Application of high speed machining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60CAD/CAM and CNC structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68Cutting fluid in milling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75The insert and its parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Coating methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82Choose the right grade for milling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84Cutting tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90Drilling tools for dies and moulds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107CoroGrip precision power chuck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116Coromant Capto . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120Machining examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124Trouble shooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170Cutting data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171Material cross reference list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183

Within the die andmould makingindustry the develop-ment has been strongthe last years. Machinetools and cutting toolsget more and moresophisticated everyday and can perform

applications at a speed and accuracy noteven thought of ten years ago. TodayCAD/CAM is very common and tomachine with so called HSM (High SpeedMachining) it is a necessity.

To manufacture a die or mould, manydifferent cutting tools are involved, fromdeep hole drills to the smallest ball noseendmills. In this application guide thewhole process of die and mould makingwill be explained with focus on the machi-ning process and how to best utilise thecutting tools. However, programming ofmachine tools, software, workpiece mate-rials, the function of different types of diesand mould will also be explained. First letus take a look at a simplified flowchart tosee what the different stages are in the dieand mould making process.

INTRODUCTION

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DIE CONSTRUCTION WORK FLOW

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1. Receiving - standard die parts,steel castings, planning andscheduling

2. Model shop - tooling aideand checking fixtures

3. CAM-room - schedule,exchange reports DNC/CNCprogramme match, layout

4. 2D-machining - shoes, pads, 5. Blocking - die packs, die design6. 3D-machining -

sub-assembled dies 7. Polishing - standard parts

and components

8. Tryout - sheet steel materialspecifications check fixture.Inspection - Functional buildevaluation, stable metal panelproduct fixture

9. Die completion - die designhandling devices, productionrequirements, inspectionrequirements

10. Feed back - die history book,check list base

11. Shipping

Simplified, the die construction work flow can be explained as in the illustration below.

1

2

103

4

5

8

7

6

10

9

11

10

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When a tool has to be made, for instance,to a hood of a car you do not make onepress tool and the material for the hoodgoes in on one side, gets pressed and comesout finished on the other side. It is oftencomplicated shapes, geometries, which hasto be pressed, with different radii and cavi-ties, to close tolerances. To do this thematerial for the hood has to be pressed inseveral press tools where a small change inthe shape is made each time. It is not unusualthat up to 10 different steps are needed tomake a complete component.

There are 5 basic types of dies and moulds;pressing dies, casting dies, forging dies, in-jection moulds and compression moulds.

Pressing dies are for cold-forming of, forinstance, automobile panels with complexshapes. When producing a bonnet for a carmany pressing dies are involved performingdifferent tasks from shaping to cutting andflanging the component. As mentionedearlier there can be over 10 different stepsin completing a component. The dies areusually made of a number of componentsnormally made of alloyed grey cast-iron.However, these materials are not suitablefor trim dies with sharp cutting edges forcutting off excessive material after thecomponent has been shaped. For this pur-pose an alloyed tool steel is used, often cast.

Example of a chain of process within theautomotive industry1. Blank die to cut out blanks from coiled

material.2. Draw die to shape the blank.3. Trim die to cut off excessive material.4. Flange die to make the initial bend for

flanges.5. Cam flange die to bend the flanges

further inside.

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Material properties especially influencingmachinability are:• Surface hardness - to resist abrasive and

adhesive wear• High content of carbides - to resist

abrasive wear• Toughness/ductility - to resist chipping

and breakage

Dies and moulds for hot work such as diecasting and forging are used for manufac-turing of for instance engine blocks. Thesedies and moulds are exposed to a numberof demanding conditions of which thefollowing are particularly critical for themachinability of the tool material.• Hot hardness - to resist plastic defor-

mation and erosion• Temperature resistance - to resist

softening at high temperature• Ductility/toughness - to resist fatigue

cracking• Hot yield strength - to resist heat checking

Moulds for plastic materials include in-jection, compression, blow and extrusionmoulds. Factors that influnence the machina-bility in a plastic mould steel are:• Hardness• Toughness/ductility• Homogenity of microstructure

and hardness

Die and mould materialThe materials described and used as refe-rence-material in this guide are mainlyfrom the steel manufacturer Uddeholm,with a cross reference list at the end of the chapter.

A substantial proportion of productioncosts in the die and mould industry isinvolved in machining, as large volumes ofmetal are generally removed. The finisheddie/mould is also subjected to strict geo-metrical- and surface tolerances.

Many different tool steels are used to pro-duce dies and moulds. In forging and diecasting the choice is generally hot-worktool steels that can withstand the relativelyhigh working temperatures involved.Plastic moulds for thermoplastics andthermosets are sometimes made from cold-work tool steel. In addition, some stainlesssteels and grey cast iron are used for diesand moulds. Typical in-service hardness isin the range of 32 - 58 HRC for die andmould material.

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Cast-iron is an iron-carbon alloy with acarbon content ofmostly 2-4% as well asother elements likesilicon, manganese,phosphorus andsulphur. Corrosionand heat resistance

may be improved with additions of nickel,chromium, molybdenum and copper.Good rigidity, compressive strength andfluidity for cast iron are typical properties.Ductility and strength can be improved byvarious treatments, which affect the micro-structure. Cast-iron is specified, not bychemical analysis, but by the respective

mechanical properties. This is partly dueto that the cooling rate affects the cast-ironproperties.

Carbon is presented as carbide-cementiteand as free carbon-graphite. The extentsof these forms depend partly on theamount of other elements in the alloy. Forinstance, a high-silicon cast-iron will bemade up of graphite with hardly anycementite. This is the type known as greyiron. The silicone content usually variesbetween 1-3%. A low amount of siliconewill stabilize carbides and the cast-ironwill be made up dominantly of cementitewith little graphite. This is a hard but weakbrittle type called white iron.

CAST-IRON

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In spite of the silicone content having adecisive influence on the structure, thecooling rate of cast iron in castings is alsoinfluential. Rapid cooling may not leaveenough time for grey iron to form, as thesilicone has not had time to decompose thecementite into the graphite. Varying sec-tional thicknesses in castings affect thecooling rate, affecting the state of carbon.Thick section will solidify into grey ironwhile thin ones will chill into white iron.Hence chilled cast-iron. Modern castingtechniques control analysis, cooling rates,etc. to provide the cast-iron componentswith the right graphite structure. Also toprovide chilled parts where needed, forinstance a wear face on a component.Manganese strengthens and toughens cast-iron and is usually present in amounts of0.5-1%.

For this reason, a thin or tapered sectionwill tend to be more white iron because ofthe cooling effect in the mould. Also thesurface skin of the casting is often harder,white iron while underneath is grey iron.

The basic structural consituents of thedifferent types of cast-iron are ferritic,pearlitic or a mixture of these.

Types of cast-iron with ferritic matrixand little or no pearlite are easy to machine.They have low strength and normally ahardness of less than 150 Brinell. Because

of the softness and high ductility of ferritethese types of cast-iron can be ”sticky”and result in built-up edge forming atlow cutting data, but this can be avoidedby increasing the cutting speed, if theoperation permits.

Types of cast-iron with ferritic/pearlitic orpearlitic matrix range from about 150 HBwith relatively low strength to high-strength, hard cast-irons of 280-300 HBwhere pearlitic matrix dominates.

Pearlite has a stronger, harder and lessductile structure than ferrite, its strengthand hardness depending on whether it hasrough or fine lamellar. The more fine-grai-ned and more fine lamellar the pearlite, thehigher strength and hardness. This meansit has smaller carbides with less abrasivewear but is more toughness demanding dueto smearing and built up edge formation.

Carbides are extremely hard constituentswhether they are of pure cementite orcontain alloying material. In thin plates, asin pearlite, cementite can be machined, butin larger particles which separate the con-stituents they drastically reduce the machi-nability. Carbides often occur in thin sec-tions, projecting parts or corners of cas-tings due to the rapid solidification, givinga finer structure, of these parts.

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Hardness of cast iron-is often measured inBrinell. It is an indication of machinability,which deteriorates with increasing Brinellhardness. But the hardness value is anunreliable measurement of machinabilitywhen there are two factors that the valuedoes not show.

In most machining operations it is the hardparts at the edges and corners of compo-nents which cause problems when machi-ning. The Brinell test cannot be carried outon edges and corners and therefore thehigh hardness in these parts is not discove-red before machining is undertaken.

A Brinell test says nothing about the cast-iron’s abrasive hardness which is the diffe-rence between the hardness on the basicstructure and the hardness of the constituente.g. a particle of carbide.

Abrasive hardness due to sand inclusionsand free carbides is very negative formachinability. A cast-iron of 200 HB andwith a number of free carbides is more dif-ficult to machine than a cast-iron of 200HB and a 100% pearlitic structure with nofree carbides.

Alloy additives in cast-iron affect machi-nability in as much as they form or preventthe forming of carbides, affect strength and/or hardness. The structure within the cast-iron is affected by the alloying materialwhich, depending on its individual character,can be divided into two groups.

1. Carbide forming: Chromium (Cr),cobalt (Co), manganese (Mr), vanadium (V).

2. Graphitizing elements: Silicone (Si),nickel (Ni), aluminium (Al), copper (Cu),titanium (Ti).

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Grey cast-ironThere is a large range of grey cast-ironswith varying tensile strengths. The siliconcontent/sectional area combinations formvarious structures of which the low-sili-con, fine graphite and pearlite make thestrongest and toughest material. Tensilestrength varies considerably throughoutthe range. A coarse graphite structuremeans a weaker type. A typical cast-iron,where metal cutting is involved, often hasa silicon content of around 2%. Commonare the austenitic types.

Nodular cast-iron (SG)The graphite is contained as round nodules.Magnesium especially is used to depositthe gobules and added to become a magne-sium-nickel alloy. Tensile strength, tough-ness and ductility are considerably impro-ved. Ferritic, pearlitic and martensitictypes with various tensile strengths occur.

The SG cast-iron is also a graphite structu-re with properties in-between that of greyand nodular cast-iron. The graphite flakesare compacted into short ones with roundends through the addition of titanium andother treatment.

Malleable cast-ironWhen white iron is heat treated in a par-ticular way, ferritic, pearlitic or martensiticmalleable cast-iron is formed. The heattreatments may turn the cementite intospherical carbon particles or remove thecarbides. The cast-iron product is malleab-le, ductile and very strong. The siliconcontent is low. Three categories occur:ferritic, pearlitic and martensitic and theymay also be categorized as Blackheart,Whiteheart and pearlitic.

Alloyed cast-ironThese are cast-irons containing largeramounts of alloying elements and, generally,these have similar effects on properties ofcast-iron as they do on steel. Alloying ele-ments are used to improve properties byaffecting structures. Nickel, chromium,molybdenum, vanadium and copper arecommon ones. The graphite-free whitecast-iron is extremely wear resistant whilethe graphite-containing cast-iron is alsoknown as heat resistant ductile cast-iron.Corrosion resistance is also improved insome types. Toughness, hardness and heatresistance are typically improved.

The main difference in these types is theform in which carbon, mainly graphiteoccurs.

The general relative machinability of thefour main kinds of cast-iron is indicated ina diagram where (A) is grey cast-iron, (B)malleable, (C) S.G. iron and (D) chilled,white cast-iron.

A B C D

1009080706050403020100

Relative machinability

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Machinability of cast-ironWhen establishing machinability characte-ristics of cast-iron grades, it is often usefulto note the analysis and structure:

• Reduced carbon content results in lowermachinability since less fracture-indica-ting graphite can be formed.

• Ferritic cast-iron with an increased sili-con content is stronger and less ductileand tends to give less build-up edge.

• Increased pearlitic content in the matrixresults in higher strength and hardnessand decreased machinability.

• The more fine lamellar and fine-grainedthe pearlite is, the lower is the machina-bility.

• The presence of about 5% of free carbidesin the matrix decreases machinabilitysubstantially.

• The effects of free carbides with respectto machinability is more negative incast-iron with pearlitic matrix, becausethe pearlite ”anchors” the carbide particlesin the matrix. This means that it isnecessary for the insert edge to cutthrough the hardest particles instead of,as can be done with a ferritic structure,”pulling” out or pushing into the softferrite.

• The top of the casting can have a some-what lower machinability due to im-purities such as slag, casting sand etc.which float up and concentrate in thissurface area.

Generally it can be said that: the higher thehardness and strength that a type of cast-ironhas, the lower is the machinability and theshorter the tool-life that can be expectedfrom inserts and tools.

Machinability of most types of cast-ironinvolved in metal cutting production isgenerally good. The rating is highly relatedto the structure where the harder pearliticcast-irons are somewhat more demandingto machine. Graphite flake cast-iron andmalleable cast-iron have excellent machi-ning properties while SG cast-iron is notquite as good.

The main wear types encountered whenmachining cast-iron are abrasion, adhesionand diffusion wear. The abrasion is produ-ced mainly by the carbides, sand inclusionsand harder chill skins. Adhesion wear withbuilt-up edge formation takes place atlower machining temperatures and cuttingspeeds. This is the ferrite part of cast-ironwhich is most easily welded onto theinsert but which can be counteracted byincreasing speed and temperature. On theother hand, diffusion wear is temperaturerelated and occurs at high cutting speeds,especially with the higher strength cast-irongrades. These grades have a greater defor-mation resistance, leading to higher tempe-rature. This type of wear is related to thereaction between cast-iron and tool andhas led to some cast-iron machining beingcarried out at high speeds with ceramictools, achieving good surface finish.

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Typical tool properties needed, generally,to machine cast-iron are high hot-hardnessand chemical stability but, depending uponthe operation, workpieces and machiningconditions, toughness, thermal shock resi-stance and strength are needed from thecutting edge. Ceramic grades are used tomachine cast-iron along with cementedcarbide.

Obtaining satisfactory results in machiningcast-iron is dependent on how the cuttingedge wear develops: rapid blunting willmean premature edge breakdown throughthermal cracks and chipping and poorresults by way of workpiece frittering,poor surface finish, excessive waviness, etc.Well developed flank wear, maintaining abalanced, sharp edge, is generally to bestrived for.

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Materieltype

GreyCast-iron

Alloyedgrey-iron

Alloyedgrey-iron

Nodularcast-iron

Nodularcast-iron

HardnessHB

150-200

220-260

210-240

200-260

230-300

Area of use

Frames

Dies

Dies

Dies&stamps

Dies&stamps

JapanJIS

FC250FC300FC350

Notavailable

Notavailable

FCD450FCD550

FCD600FCD800

FranceANFOR

Ft25

Mn450

Mn450

FGS400

FGS600

ItalyUNI

G25

GNM45

GNM45

GS370-17

GS600

Brazil

GG25

GG26

GG26

GGG60

GGG60

Materieltype

GreyCast-iron

Alloyedgrey-iron

Alloyedgrey-iron

Nodularcast-iron

Nodularcast-iron

HardnessHB

150-200

220-260

210-240

200-260

230-300

Area of use

Frames

Dies

Dies

Dies&stamps

Dies&stamps

CMCCoromant

08.1/2

07.2

07.2

09.1

09.2

SwedenSS

0125

0852

0852

0717-12

0732-3

GermanyDIN

GG25

GG26

GG26

GGG60

GGG60

USAASTM

A48 Class 40B

-

-

-

A536Grade 80-55-06

UKBS

BS1452G150

G250 +Cr % Mo

BS1452G250

BS2989600/3

BS2989700/2

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FROM QUOTATION TO A FINISHED PRESS TOOLFinding good solutionswith little materialFirst of all the die andmouldmaker has to doa quotation on thejob, which can be hardmany times since theblueprints from thecustomer often is

pretty rough outlined due to their ownongoing development of the product.

Often the tool maker receive CAD drawingsof the finished component, which looksfar from the different tools that has to bemanufactured to produce the component.This phenomenon has much to do withthe integration of computers within themanufacturing and the companies evershortened lead times on products.

There are often complicated shapes andgeometries with deep cavities and radii,which has to be pressed to close tolerances.To be able to create these shapes severaldifferent press tools has to be manufactu-red. If one company can come up with asmart solution that has fewer steps in thepressing process they have a clear advantage.

If the component to be machined is verylarge, a model of foamed plastic (styrofoam)is made with the shape of the component.The model of foamed plastic is then packedin sand and chill cast. When the meltedmetal is poured into the casting mould thefoamed plastic evaporates and you will geta blank with an optimised shape to have aslittle material to remove as possible to thefinished shape of the component. About10 mm and sometimes even less stock isleft to the final shape of the die, which savesa lot of time as much rough machining iseliminated.

A model of foamed plastic, which is close to the shape of the component to save time in rough machining

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The next step is to start up the machiningof the component. Usually this is donedirectly on the optimized blank of thetool. However, sometimes the customer orthe tool manufacturer himself wants tomake a prototype of the tool to see thateverything is correct before starting to cutchips out of the optimized blank. Which isboth expensive and can take a long time toproduce.

The prototype is normally machined inaluminium or kirkzite. Only half the toolis machined, the lower part, and is thenput up in a Quintus press. This type ofpress has a rubber stamp working as theupper part of the press tool, which pressdown on the sheet metal which forms afterthe prototype tool half. Instead of a rubberstamp there are also press techniques whereliquid is used to press the sheet metal overthe prototype tool. These procedures areoften used within the automotive industry

in order to produce several prototypecomponents to crash test to see if anychanges has to be made to the component. There are several advantages with this typeof prototype methods when it is used inlow volume part production:

• Only a single rigid tool half is required to form, trim and flange a part.

• Tool cost reductions of up to 90%.• Reduction in project lead-time.• Reduction in storage space for tools.• Increased design and material

possibilities.• The single tool half can easily be

modified to accommodate part design changes.

• No matching or fixing of tool-halves.• Several different parts can be formed in

one press cycle.• Prototype tools can often be used in

series production tools.

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The machinist can, in fact, decide thewhole milling strategy by the machine in aWOP-station (Workshop OrientedProgramming).

The machining is often structured to per-form the roughing and restmilling opera-tions during the day shift, while attendedby a machinist. The time consuming fini-shing operations are often done unmannedduring the nights and week ends. Whendoing this it is important with a goodmonitoring system on the machine toprevent that the component gets damagedif a cutting tool breaks. If a good tool wearanalysis has been made and the tool lifehas been established, automatic tool changescan be made to utilize the machine tool evenfurther. However, this calls for very accu-rate tool settings especially in the Z-axis toget as small mismatch as possible.

However, it is also very common that bothhalves of a tool is machined as the onlydifference is that it is made of aluminium.Which is easy to machine and cheaper thanthe real tool steel.

While the blank is being cast the machi-ning strategy and the tool paths are beingdecided with the help of CAM equipmentat the programming department. When theblank arrives the CNC-programme shouldbe out by the machine tool in the work-shop. In some work shops the machinetools are connected to a CAM work-sta-tion, which enables the machinist to makechanges in the programme if he realisesthat there is too much material to removein certain places or another tool might bemore suitable.

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When the machining is finished the die ormould has to be ground, stoned or polishedmanually, depending on the surface require-ments. At this stage much time and moneycan be saved if more efforts and considera-tion has been put down on the previousmachining operations.

When the press tool is thought to be finishedthe two halves must be fitted, trimmed,together. This is done by spotting, the sur-face of one of the halves is covered withink, then a component is test pressed inthe tool. If there is a clean spot somewhereon the sheet metal there might, for instance,be a radius which is wrong and need someadditional polishing done to it. You alsocheck that there is an even sheet metalcolumn all over the test piece. This spot-ting-work is time consuming and if thereis a tool, e. g. 3000 mm x 1500 mm and itshows that there is a corner 0.1 mm lowerthan everywhere else, the whole surfacehas to be ground and polished down 0.1mm, which is a very extensive job.

The die for a cutting tool after manual polishing A pressed and Spotted Workpiece

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PROCESS PLANNINGThe larger the compo-nent and the morecomplicated the moreimportant the processplanning becomes. Itis very important tohave an open mindedapproach in terms ofmachining methods

and cutting tools. In many cases it mightbe very valuable to have an external spea-king partner who has experiences frommany different application areas and canprovide a different perspective and offersome new ideas.

An open minded approach to the choice of methods, tool paths, milling and holding tools In todays world it is a necessity to becompetitive in order to survive. One ofthe main instruments or tools for this iscomputerised production. For the Die &Mould industry it is a question of inves-ting in advanced production equipmentand CAD/CAM systems.

But even if doing so it is of highest impor-tance to use the CAM-softwares to theirfull potential.

In many cases the power of tradition inthe programming work is very strong. Thetraditional and easiest way to program toolpaths for a cavity is to use the old copymilling technique, with many entrancesand exits into the material. This techniqueis actually linked to the old types of copymilling machines with their stylus that followed the model.

19

This often means that very versatile andpowerful softwares, machine and cuttingtools are used in a very limited way.

Modern CAD/CAM-systems can be usedin much better ways if old thinking, tradi-tional tooling and production habits areabandoned.

If instead using new ways of thinking andapproaching an application, there will be alot of wins and savings in the end. If using a programming technique inwhich the main ingredients are to ”sliceoff” material with a constant Z-value,using contouring tool paths in combina-tion with down milling the result will be:

• a considerably shorter machining time • better machine and tool utilisation• improved geometrical quality of the

machined die or mould• less manual polishing and try out time

In combination with modern holding andcutting tools it has been proven manytimes that this concept can cut the totalproduction cost considerably.

Initially a new and more detailed program-ming work is more difficult and usuallytakes somewhat longer time. The questionthat should be asked is, ”Where is the costper hour highest? In the process planningdepartment, at a workstation, or in themachine tool”?

The answer is quite clear as the machinecost per hour often is at least 2-3 timesthat of a workstation.

After getting familiar with the new way ofthinking/programming the programmingwork will also become more of a routineand be done faster. If it still should takesomewhat longer time than programmingthe copy milling tool paths, it will be madeup, by far, in the following production.However, experience shows that in thelong run, a more advanced and favourableprogramming of the tool paths can bedone faster than with conventional programming.

20

THE RIGHT CHOICE OF HIGHLY PRODUCTIVECUTTING TOOLS FOR ROUGHING TO FINISHING

instance. This will of course have a bigimpact on the surface finish and geometricalaccuracy of the dies or moulds that are beingfinish machined in that machine tool. It willresult in a need of more manual polishingand longer try out times. And if remem-bering that today’s target should be toreduce the manual polishing, then the stra-tegy to use the same machine tools forroughing to finishing points in totallywrong direction. The normal time tomanually polish, for instance, a tool for alarge bonnet is roughly 350-400 hours.

If this time can be reduced by good machi-ning it not only reduces the cost, but alsoenhance the geometrical accuracy of thetool. A machine tool machines pretty muchexactly what it is programmed for and the-refore the geometrical accuracy will be betterthe more the die or mold can be machined.However, when there is extensive manualfinishing the geometrical accuracy will notbe as good because of many factors such ashow much pressure and the method of poli-shing a person uses to mention two of them.

First of all:• Study the geometryof the die or mouldcarefully.

• Define minimumradii demands andmaximum cavity depth.

• Estimate roughly the amount of materialto be removed. It is important to unders-tand that roughing and semi-finishing of abig sized die or mould is performed farmore efficiently and productively withconventional methods and tooling. Alsofor big sized dies and moulds. This is dueto the fact that the material removal rate inHSM is much lower than in conventionalmachining. With exception for machiningof aluminium and non-ferrous materials.However the finishing is always more productive with HSM.

• The preparation (milled and parallelsurfaces) and the fixturing of the workpieceis of great importance. This is always oneclassic source for vibrations. If performingHSM this point is extra important. Whenperforming HSM or also in conventionalmachining with high demands on geome-trical accuracy of the die or mould, the stra-tegy should always be to perform roughing,semi-finishing, finishing and super-finishingin dedicated machines. The reasons for thisare quite obvious - it is absolutely impos-sible to keep a good geometrical accuracyon a machine tool that is used for all typesof operations and workloads.

The guide ways,ball screws andspindle bearingswill be exposedto bigger stressesand workloadswhen roughing for

21

If adding, totally, some 50 hours on advan-ced programming (minor part) and finishingin an accurate machine tool, the polishingcan often be reduced down to 100-150hours, or sometimes even less. There willalso be other considerable benefits bymachining to more accurate tolerances andsurface structure/finish. One is that theimproved geometrical accuracy gives lesstry out times. Which means shorter leadtimes. Another is that, for instance, a pres-sing tool will get a longer tool life and thatthe competitiveness will increase via highercomponent quality. Which is of highestimportance in today’s competition.

A human being can not compete, no mat-ter how skilled, with a computerised toolpath when it comes to precision. Differentpersons use different pressures when doingstoning and polishing, resulting most oftenin too big dimensional deviations. It is alsodifficult to find and recruit skilled, experi-enced labour in this field. If talking aboutHSM applications it is absolutely possible,with an advanced and adapted program-ming strategy, dedicated machine tools

and holding and cutting tools, to eliminatemanual polishing even up to 100%. Ifusing the strategy to do roughing and fini-shing in separate machines it can be a goodsolution to use fixturing plates. The die ormould can then be located in an accurateway. If doing 5-sided machining it is oftennecessary to use fixturing plates withclamping from beneath. Both the plate andthe blank must be located with cylindricalguide pins.

The machining process should be dividedinto at least three operation types; roughing,semi-finishing and finishing, some timeseven super-finishing (mostly HSM applica-tions). Restmilling operations are of courseincluded in semi-finishing and finishingoperations.

Each of these operations should be per-formed with dedicated and optimised cutting tool types.

In conventional die & mould making itgenerally means:

Roughing: Round insert cutters, end millswith big corner radii

Semi-finishing: Round insert cutters,toroid cutters, ball nose endmills

Finishing: Round insert cutters (wherepossible), toroid cutters, ball nose endmills(mainly)

Restmilling: Ball nose endmills, endmills,toroid and round insert cutters

22

In high speed machining applications itmay look the same. Especially for biggersized dies or moulds. In smaller sizes, max400 X 400 X 100 (l,w,h), and in hardenedtool steel, ball nose end mills (mainly solidcarbide) are usually first choice for alloperations. But, it is definitely possible tocompete in productivity also by usinginserted tools with specific properties.Such as round insertcutters, toroid cut-ters and ball noseend mills. Eachcase has to be indi-vidually analysed...

To reach maximumproductivity it isalso important toadapt the size ofthe milling cuttersand the inserts toa certain die ormould and toeach specific operation. The main target isto create an evenly distributed workingallowance (stock) for each tool and in eachoperation. This means that it is most oftenmore favourable to use different diameterson cutters, from bigger to smaller, especiallyin roughing and semi-finishing. Instead ofusing only one diameter throughout eachoperation. The ambition should always beto come as close as possible to the finalshape of the die or mould in each operation.

An evenly distributed stock for each toolwill also guarantee a constant and highproductivity. The cutting speed and feedrate will be on constant high levels whenthe ae/ap is constant. There will be lessmechanical variations and work load onthe cutting edge. Which in turn gives lessheat generation, fatigue and an improvedtool life.

A constant stock alsoenables for higher cuttingspeed and feed togetherwith a very secure cuttingprocess. Some semi-fini-shing operations andpractically all finishingoperations can be perfor-med unmanned or parti-ally manned. A constantstock is of course alsoone of the real basic criterias for HSM.

Another positive effect of a constant stockis that the impact on the machine tool -guide ways, ball screws and spindle bear-ings will be less negative. It is also andalways, very important to adapt the sizeand type of milling cutters to the size ofthe machine tool.

23

THE VERSATILITY OF ROUND INSERT CUTTERSIf a square shoulder cutter with triangularinserts is used it will have relatively weakcorner cross sections, creating an unpre-dictable machining behaviour. Triangularor rhombic inserts also creates big radialcutting forces and due to the number ofcutting edges they are less economicalalternatives in these operations.

On the other hand if round inserts, whichallows milling in all materials and in alldirections, are used this will give smoothtransitions between the passes and alsoleaves less and more even stock for thesemi-finishing. Resulting in a better dieor mould quality. Among the features ofround inserts is that they create a variablechip thickness. This allows for higher feedrates compared with most other insert shapes. The cutting action of round insertsis also very smooth as the entering anglesuccessively alters from nearly zero (veryshallow cuts) to 90 degrees. At maximumdepth of cut the entering angle is 45 degreesand when copying with the periphery theangle is 90 degrees. This also explains thestrength of round inserts - the work-loadis built up successively.

If the rough milling ofa cavity is done with asquare shoulder cuttermuch stair-case shapedstock has to be remo-ved in semi-finishing.This of course createsvarying cutting forcesand tool deflection.

The result is an uneven stock for finishing,which will influence the geometrical accu-racy of the die or mould.

Stock to beremoved

“Stair caseshaped” stock

Smooth transitions-little stock

Square shouldercutter, 90°

Much material remaining after roughing

Stock to beremoved

24

Round inserts should always be regarded asfirst choice for roughing and mediumroughing operations. In 5-axis machininground inserts fit in very well and havepractically no limitations. With good pro-gramming round insert cutters and toroidcutters can replace ball nose end mills to avery big extent. The productivity increasemost often ranges between 5-10 times(compared with ball nose end mills).Round insert cutters with small run-outscan in combination with ground, positiveand light cutting geometries also beused in semi-finishing and some finishingoperations.

Round insert cutter

Less material remaining after roughing

Combinationof milling directions

2525

APPLICATION TECHNOLOGYThis is very much a

question about opti-mising cutting data,grades and geometriesin relation to the spe-cific type of material,operation and produc-tivity and securitydemands.

It is always important to base calculationsof effective cutting speed on the true oreffective diameter in cut. If not doing this,there will be severe miscalculations of thefeed rate as it is dependent on the rpm fora certain cutting speed.

If using the nominal diameter value of thetool, when calculating cutting speed, theeffective or true cutting speed will bemuch lower if the depth of cut is shallow.This is valid for tools such as, round insertcutters (especially in the small diameterrange), ball nose end mills and end millswith big corner radii. The feed rate will ofcourse also be much lower and the pro-ductivity severely hampered.

Most important is that the cutting condi-tions for the tool will be much under itscapacity and recommended applicationrange. Often this leads to premature frit-tering and chipping of the cutting edge dueto too low cutting speed and heat in thecutting zone.

When doing finishing or super-finishingwith high cutting speed in hardened toolsteel it is important to choose tools thathave a coating with high hot hardness.Such as TiAlN, for instance.

One main parameter to observe when fini-shing or super-finishing in hardened toolsteel with HSM is to take shallow cuts.The depth of cut should not exceed 0,2/0,2mm (ae/ap). This is to avoid excessivedeflection of the holding/ cutting tool andto keep a high tolerance level and geo-metrical accuracy on the machined die ormould.

Choose very stiff holding and cuttingtools. When using solid carbide it isimportant to use tools with a maximumcore diameter (big bending stiffness).

TiAIN TiCN TiN Uncoated

°C

1000

800

600

400

0

26

When using inserted ball nose end mills,for instance, it is favourable to use toolswith shanks made of heavy metal (big ben-ding stiffness). Especially if the ratio over-hang/diameter is large.

Another application parameter of impor-tance is to try to use down milling toolpaths as much as possible. It is, nearlyalways, more favourable to do down millingthan up milling. When the cutting edge goesinto cut in down milling the chip thickness

has its maximum value. And in up milling,it has its minimum value. The tool life isgenerally shorter in up milling than indown-milling due to the fact that there isconsiderably more heat generated in up-,than in down milling. When the chip thick-ness in up milling increases from zero tomaximum the excessive heat is generatedas the cutting edge is exposed to a higherfriction than in down milling. The radialforces are also considerably higher in upmilling, which affects the spindle bearingsnegatively.

In down milling the cutting edge is mainlyexposed to compressive stresses, which aremuch more favourable for the propertiesof cemented or solid carbide compared withthe tensile stresses developed in up milling.

D U

D U

Vƒ Vƒ

VƒVƒ

ap/ae ≤ 0,2 mm

27

When doing side milling (finishing) withsolid carbide, especially in hardened materials, up milling is first choice. It isthen easier to get a better tolerance on thestraightness of the wall and also a better 90 degree corner. The mismatch betweendifferent axial passes will also be less, if none. This is mainly due to the direction of the cutting forces. If having a very sharpcutting edge being in cut the cutting forces tend to ”pull” or ”suck” the cuttertowards the material.

Up milling can be favourable when havingold manual milling machines with largeplay in the lead screw, because a ”counterpressure” is created which stabilizes themachining.

The best way to ensure down milling toolpaths in cavity milling is to use contouringtype of tool paths. Contouring with theperiphery of the milling cutter (for instan-ce a ball nose end mill) often results in ahigher productivity, due to more teetheffectively in cut on a larger tool diameter.If the spindle speed is limited in themachine, contouring will help keeping upthe cutting speed. This type of tool pathsalso creates less quick changes in workload and direction. This is of specificimportance in HSM applications and har-dened materials as the cutting speed andfeed are high and the cutting edge and pro-cess is more vulnerable to any changes thatcan create differences in deflection andcreate vibrations. And ultimately total toolbreakdown.

Roughing

Finishing

Up-millingDownmilling

Bending

Upmilling

Downmilling

Roughing

- 0.02 mm

0.06 mm

Finishing

0.00 mm

0.05 mm

28

FL

�

Endmills with a higher helix angle have less radial forces and usually run smoother. Endmills witha higher helix angle has more axial forces and the risk of being pulled out from the collet is greater.

Solid Carbide Endmills - Finishing/Deflection

L = overhang; d = diameter ; F = radial forceE, π = constants; k = all constants etc. put together

⇒ 20 % Overhang reduction reduce tool deflection by 50 %⇒ 20 % Increased D (Ø10 ⇒ Ø12mm) Reduce Tool Deflection By 50

� = F x L3

3 x E x I

l = π x d4

64

⇒ � = k x F x L3

d4

64k =3 x π x E

1 Upmilling

2 Low feed/tooth

3 Small radial doc

4 Low number of teeth

5 Material hardness

6 Short outstick

Relative importance

1 2 3 4 5 6Parameters

29

Copy milling and plunging operationsalong steep walls should be avoided asmuch as possible! When plunging, the chipthickness is large at a low cutting speed.Risk for frittering of the centre. Especiallywhen the cutter hits the bottom area. If thecontrol has no, or a poor, look ahead func-tion the deceleration will not be fast enoughand there will most likely be damages onthe centre.

It is somewhat better for the cutting pro-cess to do up-copying along steep walls asthe chip thickness has its maximum at amore favourable cutting speed.

Large chip thickness at very low vc Max chip thickness att recommended vc

30

But, there will be a big contact lengthwhen the cutter hits the wall, with risk forvibration, deflection or even tool breakageif the feed speed does not decelerate fastenough. There is also a risk of pulling outthe cutter from the holder due to thedirection of the cutting forces.

The most critical area when using ball noseend mills is the centre portion. Here thecutting speed is zero, which is very disad-vantageous for the cutting process. Chipevacuation in the centre is also more criti-cal due to the small space at the chiseledge. Avoid using the centre portion of aball nose end mill as much as possible. Tiltthe spindle or the workpiece 10 to 15degrees to get ideal cutting conditions.Sometimes this also gives the possibility touse shorter (and other type of) tools.

31

For a good tool life it is also more favou-rable in a milling process to stay in cutcontinuously and as long as possible. Allmilling operations have an interrupted orintermittent character due to the usage ofmulti-teeth tools.

The tool life will be considerably shorterif the tool has many entrances and exits inthe material. Which adds the amount ofthermal stresses and fatigue in the cuttingedge. It is more favourable for moderncemented carbide to have an even and hightemperature in the cutting zone than tohave large fluctuations.

Usage of coolant also adds temperaturedifferences and is in general harmful formilling operations. This will be treatedmore in detail in another chapter.

Copy milling tool paths are often a mix ofup-, and down milling (zig-zag) and givesa lot of engagements and disengagementsin cut. This is, as mentioned above, notfavourable for any milling cutter, but alsoharmful for the quality of the die ormould. Each entrance means that the toolwill deflect and there will be an elevatedmark on the surface. This is also validwhen the tool exits. Then the cutting forcesand the bending of the tool will decreaseand there will be a slight undercutting ofmaterial in the exit portion. These factorsalso speak for contouring and down millingtool paths as the preferred choice.

32

In finishing and super-finishing, especially inHSM applications, thetarget is to reach agood geometrical anddimensional accuracyand reduce or eveneliminate all manualpolishing.

In many cases it is favourable to choosethe feed per tooth, fz, identical with theradial depth of cut, ae (ƒz = ae).

This gives following advantages:• very smooth surface finish in all direc-

tions• very competitive, short machining time• very easy to polish this symmetrical

surface texture, self detecting charactervia peaks and valleys

• increased accuracy and bearing resistanceon surface gives longer tool life on dieor mould

• minimum cusp or scallop height decidesvalues on ƒz/ae/R

SCULPTURED SURFACES

R

ae

hh = R - √2R2-ae

2

4 or h ~ ae

2

8R

ƒz/aeFeed vfCusp/hTime (min)

0.05F1200h0.000110

0.075F1800h0.00024.44

0.1F2400h0.00042.50

0.15F3600h0.00091.11

0.2F4800h0.0020.62

0.25F6000h0.0030.40

R = radius of cutter h = cusp heighth = ae2 l (8 x R) Feed = Rpm x ƒz x z

Spinle speed n = 12000 rpm, cutter diameter = 6 mm

33

The pitch (u) of a milling cutter is the distance between apoint on the edge to the same point on the next edge.Milling cutters are classified into coarse, close or extra-closepitch cutters and most cutters have these three options.

(A) Close pitch means more teeth and moderate chip pocketsand permit high metal-removal rate. Normally used for cast-iron and for medium duty machining operations in steel

Close pitch is the first choice for general purpose milling andis recommended for mixed production.

(B) Coarse pitch means fewer teeth on the cutter peripheryand large chip pockets. Coarse pitch is often used for roughingto finishing of steel and where vibration tendencies are athreat to the result of the operation.

Coarse pitch is the true problem solver and is the first choicefor milling with long overhang, low powered machines orother applications where cutting forces must be minimized.

PITCHA milling cutter, beinga multi-edge tool, canhave a variable numberof teeth (z) and thereare certain factors thathelp to determine thenumber for the typeof operation. Thematerial and size of

workpiece, stability, finish and the poweravailable are the more machine orientatedfactors while the tool related include suffi-cient feed per tooth, at least two cuttingedges engaged in cut simultaneously andthat the chip capacity of the tool is ample.

A

B

U

34

(C) Extra-close pitch cutters have small chip pockets andpermits very high table feeds. These cutters are suitable formachining interrupted cast-iron surfaces, roughing cast-ironand small depth of cut in steel. Also in materials where thecutting speed has to be kept low, for instance in titanium.

Extra close pitch is the first choice for cast iron.

The milling cutters can have either even or differential pitch.The latter means unequal spacing of teeth round the cutter and is a very effective means of coming to terms with problems of vibrations.

C

35

When there is a problem with vibration itis recommended that a milling cutter withas coarse pitch as possible is used, so thatfewer inserts give less opportunities forvibration to arise. You can also removeevery second insert in the milling cutter sothat there are fewer inserts in cut. In fullslot milling you can take out so many ofthe inserts that only two remain. However,this means that the cutter being used musthave an even number of teeth, 4, 6, 8, 10 etc.With only two inserts in the milling cutter,the feed can be increased and the depth ofcut can usually be increased several times.The surface finish will also be very good.A surface finish of Ra 0.24 in hardenedsteel with a hardness of 300 HB has beenmeasured after machining with a millingcutter with an overhang of 500 mm. Inorder to protect the insert seats, the insertssitting in the seats which are not being incut can be ground down and allowed toremain in the cutter as dummy inserts.

Positioning and length of cutThe length of cut is affected by the posi-tioning of the milling cutter. Tool-life isoften related to the length of cut whichthe cutting edge must undergo. A millingcutter which is positioned in the centre ofthe workpiece gives a shorter length ofcut, while the arc which is in cut will belonger if the cutter is moved away fromthe centre line (B) in either direction.

Bearing in mind how the cutting forces act,a compromise must be reached. The direc-tion of the radial cutting forces (A) willvary when the insert edges go into and outof cut and play in the machine spindle cangive rise to vibration and lead to insertbreakage.

By moving the milling cutter off the centre,B and C, a more constant and favourabledirection of the cutting forces will beobtained. With the cutter positioned closeto the centre line the largest average chipthickness is obtained. With a large facemillit can be advantageous to move it more offcentre. In general, when facemilling, thecutter diameter should be 20-25% largerthan the cutting width.

A B C

�

36

Every time a cuttergoes into cut, the in-serts are subjected to a large or small shockload depending onmaterial, chip crosssection and the type ofcut. The initial contactbetween the cutting

edge and workpiece may be very unfavou-rable depending on where the edge of theinsert has to take the first shock. Becauseof the wide variety of possible types ofcut, only the effects of the cutter positionon the cut will be considered here.

Where the centre of the cutter is positionedoutside the workpiece (A) an unfavourablecontact between the edge of the insert andthe workpiece results.

Where the centre of the cutter is positionedinside the workpiece (B) the most favourabletype of cut results.

The most dangerous situation however, iswhen the insert goes out of cut leaving thecontact with the workpiece. The cementedcarbide inserts are made to withstand com-pressive stresses which occur every time aninsert goes into cut (down milling). On theother hand, when an insert leaves the work-piece when hard in cut (up milling) it willbe affected by tensile stresses which aredestructive for the insert which has lowstrength against this type of stress. Theresult will often end in rapid insert failure.

ENTRANCE AND EXIT OF CUT

+ -

AB

--

+

37

The basic action to take when there is a problem with vibration is to reduce the cutting forces. This can be done by using the correct tools and cutting data.

Choose milling cutters with a coarse and differential pitch.

Choose positive insert geometries.

Use as small milling cutter as possible. This is particularly importantwhen milling with tuned adaptors.

Small edge rounding (ER). Go from a thick coating to a thin one, ifnecessary use uncoated inserts.

Use a large feed per tooth, reduce the rotational speed and maintainthe table feed (= larger feed/tooth). Or maintain the rotational speed andincrease the table feed (and feed/tooth). Do not reduce the feed per tooth.

Reduce the radial and axial cutting depths.

Choose a stable tool holder such as Coromant Capto. Use the largestpossible adapter size to achieve the best stability. Use tapered exten-sions for the best rigidity.

With long overhangs, use tuned adaptors in combination with coarseand differential pitch milling cutters. Position the milling cutter as closeto the tuned adapter as possible.

Position the milling cutter off centre of the workpiece, which leads toa more favourable direction of the cutting forces.

Start with normal feed and cutting speeds. If vibration arises try intro-ducing these measures gradually, as previously described:

a) increase the feed and keep the same rpmb) decrease the rpm and keep the same feedc) reduce the axial or/and radial depth of cutd) try to reposition the cutter

38

Axial feed capabilityis an advantage inmany operations.Holes, cavities as wellas contours can beefficiently machined.Facemilling cutterswith round inserts arestrong and have big

clearance to the cutter body.

Those lend themselves to drill/mill opera-tions of various kinds. Ramping at highfeed rates and the ability to reach far intoworkpieces make round insert cutters agood tool for complicated forms. Forinstance, profile milling in five-axis machi-nes and roughing in three-axis machines.

Ramping is an efficient way to approachthe workpiece when machining pocketsand for larger holes circular interpolationis much more power efficient and flexiblethan using a large boring tool. Problemswith chip control is often eliminated as well.When ramping, the operation should bestarted around the centre, machiningoutwards in the cavity to facilitate chipevacuation and clearance. As milling cut-ters has limitations in the axial depth ofcut and varies depending on the diamater,the ramping angle for different sizes ofcutters should be checked.

The ramping angle is dependent upon thediameter of the cutters used, clearance tothe cutter body, insert size and depth of

RAMPING AND CIRCULAR INTERPOLATION

39

cut. A 32 mm CoroMill 200 cutter with12 mm inserts and a cutting depth of 6 mmcan ramp at an angle of 13 degrees. Whilstan 80 mm cutter manages 3.5 degrees. Theamount of clearance also depends upon thediameter of the cutter.

Often used within die & mould making iswhen the tool is fed in a spiral shaped pathin the axial direction of the spindle, whilethe workpiece is fixed. This is most com-mon when boring and have several advan-tages when machining holes with large dia-meters. First of all the large diameter canbe machined with one and the same tool,secondly chip breaking and evacuation isusually not a problem when machining

this way, much because of the smaller dia-meter of the tool compared to the diameterof the hole to be machined and third, therisk of vibration is small.

It is recommended that the diameter of thehole to be machined is twice the diameterof the cutter. Remember to check maximumramping angle for the cutter when usingcircular interpolation as well.

These methods are favourable for weakmachine spindles and when using longoverhangs, since the cutting forces aremainly in the axial direction.

40

One of the main crite-ria when choosing bothholding and cuttingtools is to have assmall run-out as pos-sible. The smaller therun-out is, the moreeven the workloadwill be on each insert

in a milling cutter. (Zero run-out would ofcourse theoretically give the best tool lifeand the best surface texture and finish).

In HSM applications the size of run-out isspecifically crucial. The TIR (Total Indi-cator Readout) should be maximum 10microns at the cutting edge. A good rule ofthumb is: ”For each 10 microns in addedrun out - 50% less tool life!

Balancing adds some steps to the processand typically involves:• Measuring the unbalance of a tool/

toolholder assembly.

• Reducing the unbalance by altering thetool, machining it to remove mass or bymoving counterweights on toolholders.

• Often the procedure has to be repeated,involving checking the tool again, refiningthe previous adjustments until thebalance target is achieved.

Tool balancing leaves several sources ofprocess instability untouched. One of theseis error in the fit between toolholder andspindle interface. The reason is that thereis often a measurable play in this clamp,and there may also be a chip or dirt insidethe taper. The taper will not likely line upthe same way every time. The presence ofany such contamination would createunbalance even if the tool, toolholder, andspindle were perfect in every other way.To balance tools is an additional cost tothe machining process and it should beanalysed in each case if cost reductiongained by balancing is viable. Sometimes,however, there is no alternative to get therequired quality.

CHOICE OF HOLDING TOOLS

41

The aluminium workpiece in the picture illustrates tool balancing affecting surfacefinish. The balanceable toolholder used to machine both halves of the surface wasset to two unbalance values, 100 gmm and 1.4 gmm. The more balanced tool pro-duced the smoother surface. Conditions of the two cuts were otherwise identical:12000 rpm, 5486 mm/min feed rate, 3.5 mm depth- and 19 mm width of cut, usinga toolholder with a combined mass of 1.49 kg.

Balancing tools to G-class targets, as defined by ISO 1940-1, may demand holdingthe force from unbalance far less than the cutting force the machine will see anyway.In reality, an endmill run at 20000 rpm may not need to be balanced to any betterthan 20 gmm, and 5 gmm is generally appropriate for much higher speeds. The dia-gram refers to unbalance force relating to tool and adaptor weight of 1 kg. Field Ashows the approximate cutting force on a 10 mm diameter solid endmill.

The balance equations contain:F: force from unbalance (Newton)G: G-class value, which has units of mm/secm: tool mass in kgn: spindle speed in rpmu: unbalance in gmm

r

m

e

m

mtool

CG

A

9549 x Gu = m x (gmm)

n

F = u ( n )2 (N)9549

0 20 000 40 000n (rpm)

ISO G6.3ISO G2.5

F (N)400

300

200

100

20g - mm

5g - mm

42

Unbalance

Balance class

TIR

Coromant Capto C5

Up to 0.9 gmm

up to G1.5

up to 3.5 µm

HSK 50 A

up to 3.3 ggm

up to G5.6

up to 13.4 µm

Angular error

Unbalance

Balance class

TIR

Coromant Capto C5

Up to 2.6 gmm

up to G4.4

up to 4.2 µm

HSK 50 from A

up to 9.6 ggm

up to G516.8

up to 16 µm

Parallel error

n = 20 000 rpm, weight of adapter and toll m = 1.2 kg

However, much can be done by justaiming for good balance through propertool selection, and here are some points to think of when selecting tools:• Buy quality tools and toolholders.

Look for toolholders that have beenpremachined to remove unbalance.

• Favour tools that are short and aslightweight as possible.

• Regularly inspect tools and toolholdersfor fatigue cracks and signs of distortion.

The tool unbalance that the process canaccept is determined by aspects of the pro-cess itself. These include the cutting forcesin the cut, the balance condition of themachine, and the extent to which thesetwo affect each other. Trial and error is the best way to find the unbalance target.Run the intended operation several timesto a variety of different values, for instancefrom 20 gmm and below. After each run,

upgrade to a more balanced tool and repeat.The optimal balance is the point beyondwhich further improvements in tool balancefail to improve the accuracy or surfacefinish of the workpiece, or the point inwhich the process can easily hold the spe-cific workpiece tolerances.

The key is to stay focused on the processand not aim for a G value or other arbitrarybalance target. The aim should be to achievethe most effective process as possible. Thisinvolves weighing the costs of the toolbalancing and the benefit it can deliver,and strike the right balance between them.

At high speed, the centrifugal force mightbe strong enough to make the spindle boregrow slightly. This has a negative effect onsome V-flange tools which contact thespindle bore only in the radial plane.Spindle growth can cause the tool to be

43

drawn up into the spindle by the constantpull of the drawbar. This can lead to astuck tool or dimensional inaccuracy inthe Z-axis.

Tools with contact both in the spindle boreand face, radial and axial contact, simul-taneous fit tools are more suited formachining at high speeds. When the spindlebegins to grow, the face contact prevents

the tool from moving up the bore. Toolswith hollow shank design are also susceptibleto centrifugal force but they are designedto grow with the spindle bore at highspeeds. The tool/spindle contact in bothradial and axial direction also gives a rigidtool clamping enabling aggressive machining.The Coromant Capto coupling, due to itspolygon design, is superior when it comesto high torque and productive machining.

0 5000 10000 15000

Rotational speed n [rpm]

Vib

ratio

n se

verit

y [m

m/s

] 4.0

3.0

2.0

1.0

0.0

Unbalance vs Vibration severity at bearingSpindle IBAG 170.2 Tool weight 1.2 kg

160 gmm

80 gmm

40 gmm

20 gmm

10 gmm

<2 gmm

44

T p2

�min

�m

ax

AT�

2

� d

L

D

� 2

D1

De

Le

Li

Spindle speed

0

20000

25000

30000

35000

40000

ISO40

100%

100%

37%

31%

26%

26%

HSK 50A

100%

95%

91%

83%

72%

67%

Coromant Capto C5

100%

100%

99%

95%

91%

84%

Taper contact surfaceFace contactsurface

External taper

Inner taper

Length of taperLength of taper

Face contact surface

Manufactured angle of the taperNominal

taper angle

Nominal taper

Taper interface angle

Taper diameter tolerance area

Nominal taper

Tolerance for roundness

Cross sectiontolerance areafor roundness

Surface contact of spindle interface at high spindle speed

The roundness and concentricity are themost crucial factors for toolholders andnot the tolerance class (AT).

45

When planning for HSM one should striveto build tools using a holder cutter com-bination that is symmetrical. There aresome different tool systems which can beused. However, a shrink fit system wherethe toolholder is heated up and the boreexpands and then clamps the tool when

cooling down is considered to be one ofthe best and most reliable for HSM. Firstbecause it provides very low run-out,secondly the coupling can transmit a hightorque, thirdly it is easy to build customizedtools and tool assemblies and finally itgives high total stiffness in the assembly.

46

To maintain maximumproductivity whenroughing a cavity it isimportant to choose aseries of extensionsfor the cutter. It is avery bad compromiseto start with the long-est extension, as the

productivity will be very low.

It is recommended to change to extendedtools at pre-determined positions in theprogram. The geometry of the die or moulddecides where to change.

Cutting data should also be adapted toeach tool length to keep up maximumproductivity.

When the total tool length, from the gaugeline to the lowest point on the cuttingedge, exceeds 4-5 times the diameter at thegauge line, tuned, tapered bars should beused. Or, if the bending stiffness must beradically increased, extensions made ofheavy metal should be used.

When using extended tools it is importantto choose biggest possible diameter on theextensions and adaptors relatively to thecutter diameter. Every millimeter is im-portant for maximum rigidity, stiffness andproductivity. It is not necessary to have morethan 1 mm radially in difference betweenholding and cutting tool. The easiest wayto achieve this is to use oversized cutters.

Modular tools increases the flexibility andthe number of tool combination possibilities.

EXTENDED TOOLS IN ROUGHING OF A CAVITY

47

MACHINING IN SEGMENTSWhen machining hugepress dies it is oftennecessary to index theinserts several times.Instead of doing thismanually and inter-rupting the cuttingprocess, this can bedone in an organised

way if precautions are taken in the processplanning and programming.

Based on experience, or other information,the amount of material, or the surface tomachine, can be split up in portions orsegments. The segments can be chosenaccording to natural boundaries or bebased on certain radii sizes in the die ormould. What is important is that each seg-ment can be machined with one set ofinsert edges or solid carbide edges, plus asafety margin, before being changed tonext tool in that specific family of replace-ment tools.

This technique enables full usage of theATC (Automatic Tool Changer) and re-placement tools (sister tools).

The technique can be used for roughing tofinishing. Today’s touch probes or lasermeasuring equipment gives very precisemeasuring of tool diameter and length anda matching (of surfaces) lower than 10microns. It also gives several benefits such as:

• Better machine tool utilisation- lessinterruptions, less manual tool changing

• Higher productivity-easier to optimisecutting data

• Better cost efficiency-optimisation vsreal machine tool cost per hour

• Higher die or mould geometricalaccuracy-the finishing tools can bechanged before getting excessive wear

48

The traditional way ofmachining a corner isto use linear move-ments (G1) with non-continuous transitionsin the corner. Whichmeans that when thecutter comes to thecorner it has to be slo-

wed down because of dynamic limitationsof the linear axes. And there will even be avery short stop before the motors canchange the feed direction. As the spindlespeed is the same, the situation creates alot of excessive friction and heat. If forinstance aluminium or other light alloysare machined they can get burning marksor even start to burn due to this heat. Thesurface finish will deteriorate optically andin some materials even structurally, evenbeyond the tolerance demands.

In traditional machining of corners the toolradius is identical with the corner radius.Which gives maximum contact length anddeflection (often one quadrant).

The most typical result is vibrations, thebigger the longer the tool, or total tooloverhang is. The wobbling cutting forcesoften also creates undercutting of the corner.

There is of course also a risk for fritteringof edges or total tool break down.Some solutions on this problem are:

• Use a cutter with a smaller radius toproduce the desired corner radius on thedie or mould. Use circular interpolation(G2, G3) to produce the corner. Thismovement type does not create any definitestop at block borders. Which means thatthe movement gives smooth continuoustransitions and there is only a small chancethat a vibration should start.

• Another solution is to produce a biggercorner radius, via circular interpolation,than stated in the drawing. This can befavourable sometimes as it allowes to usea bigger cutter diameter in roughing tokeep up maximum productivity.

METHODS FOR MACHINING OF CORNERS

Stockto remove

49

• The remaining stock in the corner canthen be machined via restmilling (rest =remaining stock) with a smaller cutterradius and circular interpolation. The rest-milling of corners can also be performedby axial milling. It is important to use agood programming technique with a smoothapproach and exit. It is very important toperform the restmilling of corners beforeor as a semi-finishing operation - giveseven stock and high productivity in fini-shing. If the cavity is deep (long overhang)the ap/ae should be kept low to avoiddeflection and vibration (ap/ae appr. 0,1-0,2 mm in HSM applications in hardenedtool steel).

If consequently using a programmingtechnique based on circular interpolation(or NURBS-interpolation), which givesboth continuos tool paths and commandsof feed and speed rates, it is possible todrive the mechanic functions of a machinetool to much higher speeds, accelerationsand decelerations.

This can result in productivity gainsranging between 20-50%!

Ø8

R10

R4

50

A. Pre-drilling of astarting hole. Cornerscan be pre-drilled aswell. Not recommen-dable method as oneextra tool is needed.Which also adds moreunproductive positio-ning and tool changing

time. The extra tool also blocks oneposition in the tool magazine. From a cut-ting point of view the variations in cuttingforces and temperature when the cutterbreaks through the pre-drilled holes in thecorners is negative. The re-cutting of chipsalso increases when using pre-drilled holes.

B. If using a ball nose end mill, inserted orsolid carbide, it is common to use a peck-drilling cycle to reach a full axial depth ofcut and then mill the first layer of the cavity.This is then repeated until the cavity isfinished. The drawback with this start ischip evacuation problems in the centre ofthe end mill. Better than using a peck-dril-ling cycle is to reach the full axial depth ofcut via circular interpolation in helix. Im-portant also then to help evacuate the chips.

C. One of the best methods is to do linearramping in X/Y and Z to reach a full axialdepth of cut. Note that if choosing theright starting point, there will be no needof milling away stock from the rampingpart. The ramping can start from in to outor from out to in depending on the geo-metry of the die or mould. The main crite-ria is how to get rid of the chips in the bestway. Down milling should be practised in

METHODS FOR MACHINING OF A CAVITY

1234

5

Peck-drilling cycle with a short delay between each down-feed to evacuate chips.

Requireddepth of cutfor machiningthe first layer.

A

B

51

D. If using round insert cutters or endmills with a ramping capacity the mostfavourable method is to take the first axialdepth of cut via circular interpolation inhelix and follow the advice given in theprevious point.

a continuous cutting. When taking a newradial depth of cut it is important toapproach with a ramping movement or,better, with a smooth circular interpola-tion. In HSM applications this is crucial.

C D

52

HSM - HIGH SPEED MACHINING

53

There are a lot ofquestions about HSMtoday and many diffe-rent, more or lesscomplicated, defini-tions can be seen fre-quently. Here thematter will be discus-sed in an easy fashion

and from a practical point of view.

Historical backgroundThe term High Speed Machining (HSM)commonly refers to end milling at highrotational speeds and high surface feeds.For instance, the routing of pockets in alu-minum airframe sections with a very highmaterial removal rate. Over the past 60years, HSM has been applied to a widerange of metallic and non-metallic work-piece materials, including the productionof components with specific surface topo-graphy requirements and machining ofmaterials with a hardness of 50 HRC andabove. With most steel components harde-ned to approximately 32-42 HRC, machi-ning options currently include:

• rough machining and semi-finishing of the material in its soft (annealed) condition

• heat treatment to achieve the final re-quired hardness (</= 63 HRC)

• machining of electrodes and Electrical Discharge Machining (EDM) of specificparts of the dies or moulds (specifically small radii and deep cavities with limitedaccessibility for metal cutting tools)

• finishing and super-finishing of cylin-drical/flat/cavity surfaces with appro-priate cemented carbide, cermet, solid carbide, mixed ceramic or polycrystallinecubic boron nitride (PCBN)

With many components, the productionprocess involves a combination of theseoptions and in the case of dies and mouldsit also includes time consuming hand finishing. Consequently, production costs can be high and leadtimes excessive.

Typical for the die and mould industry isto produce one or a few tools of the samedesign. The process includes constantchanges of the design. And because of theneed of design changes there is also a cor-responding need of measuring and reverseengineering.

The main criteria is the quality of the dieor mould regarding dimensional, geo-metrical and surface accuracy. If the qualitylevel after machining is poor and if it cannot meet the requirements there will be avarying need of manual finishing work.This work gives a satisfying surface accu-racy, but it always has a negative impact onthe dimensional and geometrical accuracy.

One of the main targets for the die andmould industry has been, and is, to reduceor eliminate the need of manual polishingand thus improve the quality, shorten theproduction costs and lead times.

54

Main economical and technical factors for the development of HSM Survival - the ever increasing competitionon the marketplace is setting new stan-dards all the time. The demands on timeand cost efficiency is getting higher andhigher. This has forced the development ofnew processes and production techniquesto take place. HSM provides hope andsolutions...

Materials - the development of new, moredifficult to machine materials has underlinedthe necessity to find new machining solu-tions. The aerospace industry has its heatresistant and stainless steel alloys. Theautomotive industry has different bimetalcompositions, Compact Graphite Iron andan ever increasing volume of aluminum.The die and mold industry mainly has toface the problem to machine high hardenedtool steels. From roughing to finishing.

Quality - the demand on higher compo-nent or product quality is a result of thehard competition. HSM offers, if appliedcorrectly, solutions in this area. Substitu-tion of manual finishing is one example.Especially important on dies or moulds orcomponents with a complex 3D geometry.

Processes - the demands on shorter through- put times via fewer set-ups and simp-lified flows (logistics) can be solved to abig extent via HSM. A typical target withinthe die and mould industry is to make acomplete machining of fully hardenedsmall sized tools in one set-up. Costly andtime consuming EDM-processes can alsobe reduced or eliminated via HSM.

Design & development - one of the maintools in today’s competition is to sell pro-ducts on the value of novelty. The averageproduct life cycle on cars is today 4 years,

1600

1200

800

400

00 600 1200 1800 2400 3000

°C

Chip removal temperature as a result of the cutting speed

Steel

Cast Iron

Ironcarbon alloys

Tungsten Carbide 900°

Stellite 850°C

High speed 650°C

Carbon steel 450°C

Non-ferrous metals

Chi

p r

emov

al t

emp

erat

ur �

°

Cutting speed vcConventional machining area

Machinable

Machinable

55

computers and accessories 1,5 years, handphones 3 months... One of the prerequisitesof this development of fast design changesand rapid product development time is theHSM technique.

Complex products - there is an increaseof multifunctional surfaces on components.Such as new design of turbine bladesgiving new and optimised functions andfeatures. Earlier design allowed polishingby hand or with robots (manipulators).The turbine blades with the new, moresophisticated design has to be finished viamachining and preferably by HSM. There are also more and more examples ofthin walled workpieces that has to bemachined (medical equipment, electronics,defence products, computer parts).

Production equipment - the strong deve-lopment of cutting materials, holdingtools, machine tools, controls and especiallyCAD/CAM features and equipment hasopened possibilities that must be met withnew production methods and techniques.

The original definition of HSMSalomons theory, “Machining with highcutting speeds...“ on which he got a Germanpatent 1931, assumes that “at a certain cut-ting speed (5-10 times higher than in con-ventional machining), the chip removaltemperature at the cutting edge will startto decrease...“.

Giving the conclusion: ...“seem to givea chance to improve productivity inmachining with conventional tools at highcutting speeds...“

Modern research has unfortunately not beenable to verify this theory to its full extent.There is a relative decrease of the tempera-ture at the cutting edge that starts at certaincutting speeds for different materials. The

decrease is small for steel and cast iron.And bigger for aluminum and other non-ferrous metals. The definition of HSMmust be based on other factors.

What is today’s definition of HSM?The discussion about high speed machiningis to some extent characterised by confusion.There are many opinions, many myths andmany different ways to define HSM.Looking upon a few of these definitionsHSM is said to be:

• High Cutting Speed (vc) Machining...• High Spindle Speed (n) Machining...• High Feed (vf) Machining...• High Speed and Feed Machining...• High Productive Machining...

56

On following pages the parameters thatinfluence the machining process andhaving connections with HSM will bediscussed. It is important to describe HSMfrom a practical point of view and we alsowant to give as many practical guidelinesfor the application of HSM as possible.

True cutting speedAs cutting speed is dependent on bothspindle speed and the diameter of the tool,HSM should be defined as “true cuttingspeed“ above a certain level. The lineardependence between cutting speed and

feed rate results in “high feeds with highspeeds“. The feed will become even higherif a smaller cutter diameter is chosen, pro-vided that the feed per tooth and the numberof teeth is unchanged. To compensate for asmaller diameter the rpm must be increasedto keep the same cutting speed...and theincreased rpm gives a higher vf.

De = 2 √ap (Dc - ap)

Effective cutting speed (ve)

ve = π x n x De m/min

1000

Shallow cutsVery typical and necessary for HSM appli-cations is that the depths of cut, ae and apand the average chip thickness, hm, aremuch lower compared with conventionalmachining. The material removal rate, Q,is consequently and considerably smallerthan in conventional machining. With theexception when machining in aluminium,other non- ferrous materials, in finishingand superfinishing operations in all typesof materials.

Formula for feed speed.

Vf = fz x n x zn [mm/min]

ap x ae x vf [cm3/min]1000

Q =

Formula for material removal rate.

Characteristics of today’s HSM in hardened tool steelWithin the die & mould area the maximumeconomical workpiece size for roughing tofinishing with HSM is approximately 400X 400 X 150 (l, w, h). The maximum sizeis related to the relatively low materialremoval rate in HSM. And of course also tothe dynamics and size of the machine tool.

Most dies or moulds have a considerablysmaller size, than mentioned above, incomplete machining (single set-up).Typical operations performed are, roughing,semi-finishing, finishing and in many casessuper-finishing. Restmilling of corners and

57

of the cases solid carbide end mills or ballnose end mills. End mills with big cornerradii are often used. The solid carbidetools have reinforced cutting edges andneutral or negative rakes (mainly for mate-rials above 54 HRC). One typical andimportant design feature is a thick core formaximum bending stiffness.

It is also favourable to use ball nose endmills with a short cutting edge and contactlength. Another design feature of importanceis an undercutting capability, which isnecessary when machining along steep wallswith a small clearance. It is also possible touse smaller sized cutting tools with index-able inserts. Especially for roughing andsemi-finishing. These should have maximumshank stability and bending stiffness. Atapered shank improves the rigidity. Andso does also shanks made of heavy metal.

radii should always be done to create con-stant stock for the following operation andtool. In many cases 3-4 tool types are used.

The common diameter range is from 1 - 20mm. The cutting material is in 80 to 90%

58

The geometry of the die or mould couldpreferably be shallow and not too complex.Some geometrical shapes are also moresuited for high productive HSM. The morepossibilities there are to adapt contouringtool paths in combination with downmilling,the better the result will be.

One main parameter to observe when fini-shing or super-finishing in hardened toolsteel with HSM is to take shallow cuts.The depth of cut should not exceed 0,2/0,2mm (ae/ap). This is to avoid excessivedeflection of the holding/cutting tool andto keep a high tolerance level and geo-metrical accuracy on the machined die ormould. An evenly distributed stock foreach tool will also guarantee a constant andhigh productivity. The cutting speed andfeed rate will be on constant high levelswhen the ae/ap is constant. There will be

less mechanical variations and work loadon the cutting edge plus an improved toollife.

Cutting dataTypical cutting data for solid carbide endmills with a TiC,N or TiAlN-coating inhardened steel: (HRC 54-58)

RoughingTrue vc: 100 m/min, ap: 6-8% of the cutterdiameter, ae: 35-40% of the cutter diameter,ƒz: 0,05-0,1 mm/z

Semi-finishingTrue vc: 150-200 m/min, ap: 3-4% of thecutter diameter, ae: 20-40% of the cutterdiameter, ƒz: 0,05-0,15 mm/z

Finishing and super-finishing True vc: 200-250 m/min, ap: 0,1-0,2 mm,

Typical workpieces for HSM, forging die for anautomotive component, moulds for a plasticbottle and a headphone.

59

ae: 0,1-0,2 mm, fz: 0,02-0,2 mm/zThe values are of course dependent of out-stick, overhang, stability in the application,cutter diameters, material hardness etc.They should be looked upon as typicaland realistic values. In the discussion aboutHSM applications one can sometimes seethat extremely high and unrealistic valuesfor cutting speed is referred to. In thesecases vc has probably been calculated onthe nominal diameter of the cutter. Not

Practical definition of HSM - conclusion• HSM is not simply high cutting speed.

It should be regarded as a processwhere the operations are performedwith very specific methods and produc-tion equipment.

• HSM is not necessarily high spindlespeed machining. Many HSM applica-tions are performed with moderatespindle speeds and large sized cutters.

• HSM is performed in finishing in har-dened steel with high speeds and feeds,often with 4-6 times conventional cut-

Material Hardness Conv. vc HSM ve, R HSM ve, FSteel 01.2 150 HB <300 >400 <900

Steel 02.1/2 330 HB <200 >250 <600

Steel 03.11 300 HB <100 >200 <400

Steel 03.11 39 -48 HRc <80 >150 <350

Steel 04 48-58 HRc <40 >100 <250

GCI 08.1 180 HB <300 >500 <3000

Al/Kirksite 60-75 HB <1000 >2000 <5000

Non-ferr 100 HB <300 >1000 <2000

HSM Cutting Data by Experience

Dry milling with compressed air or oil mist under high pressure is recommended.

ting data.• HSM is High Productive Machining in

small-sized components in roughing tofinishing and in finishing and super-fini-shing in components of all sizes.

• HSM will grow in importance the morenet shape the components get.

• HSM is today mainly performed intaper 40 machines.

the effective diameter in cut.One example:

• End mill with 90 degree corner, diameter6 mm. Spindle speed at true cuttingspeed of 250 m/min = 13 262 rpm

• Ball nose end mill, nominal diameter 6mm. ap 0,2 mm gives effective diameterin cut of 2,15 mm. Spindle speed at truecutting speed of 250 m/min = 36 942 rpm

60

Main application areas for HSMMilling of cavities. As have been discussed earlier, it is possible toapply HSM-techno-logy (High SpeedMachining) inqualified, high-

alloy tool steels up to 60-63 HRc.

When milling cavities in such hardmaterials, it is crucial to select adequatecutting and holding tools for each specificoperation; roughing, semi-finishing andfinishing. To have success, it is also veryimportant to use optimised tool paths, cutting data and cutting strategies. Thesethings will be discussed in detail in comingchapters.

Die casting dies. This is an area whereHSM can be utilised in a productive wayas most die casting dies are made of de-manding tool steels and have a moderateor small size.

Forging dies. Most forging dies are suitablefor HSM due to the shallow geometry thatmany of them have. Short tools alwaysresults in higher productivity due to lessbending (better stability). Maintenance offorging dies (sinking of the geometry) is avery demanding operation as the surface isvery hard and often also has cracks.

THE APPLICATION OF HIGH SPEED MACHINING

61

Milling of electrodes in graphite and copper. An excellent area for HSM.Graphite can be machined in a productiveway with TiCN-, or diamond coated solidcarbide endmills. The trend is that themanufacturing of electrodes and employ-ment of EDM is steadily decreasing whilematerial removal with HSM is increasing.

Injection moulds and blow moulds arealso suitable for HSM, especially becauseof their (most often) small size. Whichmakes it economical to perform all opera-tions (from roughing to finishing) in oneset up. Many of these moulds have relative-ly deep cavities. Which calls for a verygood planning of approach, retract andoverall tool paths. Often long and slendershanks/extensions in combination withlight cutting tools are used.

Modelling and prototyping of dies andmoulds. One of the earliest areas forHSM. Easy to machine materials, such as

non-ferrous, aluminium, kirkzite et cetera.The cutting speeds are often as high as1500-5000 m/min and the feeds areconsequently also very high.

62

Low cutting force gives a small andconsistent tool deflection. This, in com-bination with a constant stock for eachoperation and tool, is one of the prerequi-sites for a highly productive and safe process.

As the depths of cut are typically shallowin HSM, the radial forces on the tool andspindle are low. This saves spindle bearings,guide-ways & ball screws. HSM and axialmilling is also a good combination as the

Top picture HSM, feed faster than heatpropagation. Lower picture, conventionalmilling, time for heat propagation.

HSM is also very often used in direct production of -• Small batch components• Prototypes and pre-series in

Al, Ti, Cu for the Aerospaceindustry, Electric/Electronicindustry, Medical industryDefence industry

• Aircraft components, especi-ally frame sections but also engine parts

• Automotive components, GCI and Al

• Cutting and holding tools (through hardened cutter bodies)

Targets for HSM of dies and mouldsOne of the main targets with HSM is tocut production costs via higher productivity.Mainly in finishing operations and often inhardened tool steel.

Another target is to increase the overallcompetitiveness through shorter lead anddelivery times. The main factors, whichenables this are:• production of dies or moulds in

(a few or) a single set-up • improvement of the geometrical accu-

racy of the die or mould via machining,which in turn will decrease the manuallabour and try-out time

• increase of the machine tool and work-shop utilisation via process planningwith the help of a CAM-system andworkshop oriented programming

Advantages with HSMCutting tool and workpiece temperatureare kept low. Which gives a prolonged toollife in many cases. In HSM applications, onthe other hand, the cuts are shallow and theengagement time for the cutting edge is ex-tremely short. It can be said that the feedis faster than the time for heat propagation.

63

impact on the spindle bearings is small andthe method also allows longer tools withless risk for vibrations.

Productive cutting process in small sizedcomponents. Roughing, semi-finishing andfinishing is economical to perform whenthe total material removal is relatively low.

Productivity in general finishing andpossibility to achieve extremely goodsurface finish. Often as low as Ra ~ 0,2microns.

Machining of very thin walls is possible.As an example the wall thickness can be0,2 mm and have a height of 20 mm if uti-lising the method shown in the figure.Downmilling tool paths to be used. Thecontact time, between edge and workpiece, must be extremely short to avoidvibrations and deflection of the wall. Themicrogeometry of the cutter must be verypositive and the edges very sharp.

Cutting force (Fc) vs cutting speed (vc) for a constant cutting power of 10 kW

Cutting speed vs specific cutting force in aluminium 7050

0 500 1000 1500 2000 2500 3000Vc [m/min]

Fc [N]

2500

2000

1500

1000

500

0

kc1[N/mm2]

800

700

600

500

0 500 1000 1500 2000 2500 3000Vc [m/min]

The impulse law

Fc x tengage = mwall x ∆vwall

Time of engagement is reduced with HSM

�Impulse is reduced

�Deflection is reduced

64

sometimes be increased when EDM isreplaced with machining. EDM can, ifincorrectly performed, generate a thin, re-hardened layer directly under the meltedtop layer. The re-hardened layer can be upto ~20 microns thick and have a hardnessof up to 1000 Hv. As this layer is conside-rably harder than the matrix it must beremoved. This is often a time consumingand difficult polishing work. EDM can alsoinduce vertical fatigue cracks in the meltedand resolidified top layer. These cracks can,during unfavourable conditions, even leadto a total breakage of a tool section.

Design changes can be made very fast viaCAD/CAM. Especially in cases where thereis no need of producing new electrodes.

A) Traditional process. Non-hardened (soft) blank (1), roughing (2) and semi-finishing (3). Hardening to the final service condi-tion (4). EDM process - machining of electrodes and EDM of small radii and corners at big depths (5). Finishing of parts of thecavity with good accessability (6). Manual finishing (7).

B) Same process as (A) where the EDM-process has been replaced by finish machining of the entire cavity with HSM (5).Reduction of one process step.

C) The blank is hardened to the final service condition (1), roughing (2), semi-finishing (3) and finishing (4). HSM most oftenapplied in all operations (especially in small sized tools). Reduction of two process steps. Normal time reduction compared withprocess (A) by approximately 30-50%.

= Manual finishing

Geometrical accuracy of dies and mouldsgives easier and quicker assembly. Nohuman being, no matter how skilled, cancompete with a CAM/CNC-produced sur-face texture and geometry. If some morehours are spent on machining, the timeconsuming manual polishing work can becut down dramatically. Often with asmuch as 60-100%!

Reduction of production processes as har-dening, electrode milling and EDM can beminimised. Which gives lower investmentcosts and simplifies the logistics. Less floorspace is also needed with fewer EDM-equipment. HSM can give a dimensionaltolerance of 0,02 mm, while the tolerancewith EDM is 0,1-0,2 mm. The durability,tool life, of the hardened die or mould can

EDM

65

• Good work and process planning ne-cessary - “feed the hungry machine...”

• Safety precautions are necessary: Usemachines with safety enclosing -bullet proof covers! Avoid long over-hangs on tools. Do not use “heavy”tools and adaptors. Check tools,adapters and screws regularly forfatigue cracks. Use only tools withposted maximum spindle speed. Donot use solid tools of HSS!

An example of the consequences of breakage at high speed machining isthat of an insert breaking loose from a 40 mm diameter end mill at a spindlespeed of 40.000 rpm. The ejected insert, with a mass of 0.015 kg, will fly offat a speed of 84 m/s, which is an energy level of 53 Nm - equivalent to thebullet from a pistol and requiring armour plated glass.

n = 40,000 rpm

m = 0.015 kgv = 84 m/s

ø40

E = 53 Nm

Some disadvantages with HSM• The higher acceleration and deceleration

rates, spindle start and stop give a rela-tively faster wear of guide ways, ballscrews and spindle bearings. Whichoften leads to higher maintenance costs…

• Specific process knowledge, program-ming equipment and interface for fastdata transfer needed.

• It can be difficult to find and recruitadvanced staff.

• Considerable length of “trial and error”period.

• Emergency stop is practically unneces-sary! Human mistakes, hard-, or sof-tware errors give big consequences!

66

Some specific demands on cuttingtools made of solid carbide• High precision grinding giving run-out

lower than 3 microns • Shortest possible protrusion and

overhang, maximum stiffness, and thickcore for lowest possible deflection

• Short edge and contact length for lowestpossible vibration risk, low cutting forcesand deflection

• Oversized and tapered shanks, especiallyimportant on small diameters

• Micro grain substrate, TiAlN-coatingfor higher wear resistance/hot hardness

• Holes for air blast or coolant• Adapted, strong micro geometry for

HSM of hardened steel • Symmetrical tools, preferably balanced

by design

Specific demands on cutters with indexable inserts• Balanced by design• High precision regarding run-out, both

on tip seats and on inserts, maximum10 microns totally...

• Adapted grades and geometries forHSM in hardened steel

• Good clearance on cutter bodies toavoid rubbing when tool deflection(cutting forces) disappears

• Holes for air blast or coolant• Marking of maximum allowed rpm

directly on cutter bodies.

Some typical demands on the machine tool and the data transfer in HSM(ISO/BT40 or comparable size, 3-axis)

• Spindle speed range < = 40 000 rpm

• Spindle power > 22 kW

• Programmable feed rate40-60 m/min

• Rapid traverse < 90 m/min

• Axis dec./acceleration > 1 g(faster w. linear motors)

• Block processing speed 1-20 ms

• Data flow via Ethernet250 Kbit/s (1 ms)

• Increments (linear) 5-20 microns

• Or circular interpolation via NURBS (no linear increments)

• High thermal stability and rigidityin spindle - higher pretension andcooling of spindle bearings

• Air blast/coolant through spindle

• Rigid machine frame with high vib-ration absorbing capacity

• Different error compensations -temperature, quadrant, ball screware the most important

• Advanced look ahead function inthe CNC

67

Surface with (red line) and without (blue line) run-out.

Tool life as a function of TIR % of chip thickness

Tool-life[%]

100

80

60

40

20

00 20 40 60 80 100

TIR [%]

Profile depth

Exempel: Two edge cutter. Profile depth Rz =ƒz2

4 x Dc

ƒz

Run outs influence on surface quality

Run outs influence on surface quality

68

CAD

CAM

PP

CNC

CAQ

CAD/CAM and CNC structuresHSM processes has underlined the necessity to develop both the CAM-, andCNC-technology radically. HSM is not simply a question of controlling and drivingthe axes and turning the spindles faster. HSM applications creates a need of muchfaster data communication between different units in the process chain. There arealso specific conditions for the cutting process in HSM applications that conven-tional CNCs can not handle.

The typical structure for generating data and perform the cutting and measuringprocess may look like this:

Re-design, re-engineering or direct tool compensations due to tool wear or changeof tools etc.. New loop begins.

This type of process structure is characterised by specific configuration of data foreach computer. The communication of data between each computer in this chainhas to be adapted and translated. And the communication is always of one way-type.There are often several types of interfaces without a common standard.

Workpiece geometry. CAD - creation/design of a geometrical 3D model based on advanced mathematical calculations (Bezier curves or NURBS)

Generic tool path. Creation of CAM - files representing tool paths, methods of approach, tool and cutting data et cetera

NC program. Generation of a part program (NC-program) via post-processing of CAM - files to a specific type of control

Workpiece. Machining of the component, die or mould etc. via commands from a CNC

Measuring data. Registration and feedback of measuring data, CAQ, Computer Aided Quality assurance

69

Problem areasThe main problem is that a conventionalcontrol (CNC) does not understand theadvanced geometrical information from theCAD/CAM systems without a translationand simplification of the geometry data.

This simplification means that the higherlevel geometry (complex curves) from theCAD/CAM is transformed to tool pathsvia primitive approximations of the toolpaths, based on straight lines betweenpoints within a certain tolerance band.Instead of a smooth curve line geometrythere will be a linearised tool path. Inorder to avoid visible facets, vibrationmarks and to keep the surface finish on ahigh level on the component the resolutionhas to be very high. The smaller the tole-rance band is (typical values for the distancebetween two points range from 2 to 20

microns), the bigger the number of NC-blocks will be. This is also true for thespeeds - the higher cutting and surfacespeed the bigger the number of NC-blocks.

This has today resulted in limitations ofsome HSM applications as the block cycletimes have reached levels close to 1 msec. Such short block cycle times requires avery huge data transfer capacity. Whichwill create bottle necks for the entire pro-cess by overloading factory networks andalso demand large CNC-memory and highcomputing power.

If one NC-block typically consists of 250bits and if the block cycle time rangesbetween 1 - 5 msec the CNC has to handlebetween 250 000 to 50 000 bits/sec!

P0, G0

CADgeometry principle

e.g. NURBS

CADgeometry principle

standard

P1, G1

P2, G2

P3, G3K

M

P0 P1

P0 P1

G01

G03

70

New NURBS-based technologyThe recently developed solution on theabove problems is based on what could becalled ”machine independent NC-pro-gramming”.

This integration of CAD ⇒ CAM ⇒ CNCimplys that the programming of the CNCconsiders a generic machine tool thatunderstands all geometrical commandscoming from the NC-programming. Thetechnique is based on the CNC automati-cally adapting the specific axle and cutterconfiguration for each specific machinetool and set-up.

This includes, for instance, corrections ofdisplacements of workpieces (on themachine table) without any changes in theNC-program. This is possible as the NC-program is relative to different deviationsfrom the real situation.

Tool paths based on straight lines have noncontinuous transitions. For the CNC thismeans very big jumps in velocity betweendifferent directions of the machine axes.The only way the CNC can handle this isby slowing down the speed of the axes inthe ”change of direction situation”, forinstance in a corner. This means a severeloss of productivity.

A NURBS is built up by three parameters.These are poles, weights and knots. AsNURBS are based on non-linear move-ments the tool paths will have continuoustransitions and it is possible to keep muchhigher acceleration, deceleration and inter-polation speeds. The productivity increasecan be as much as 20-50%. The smoothermovement of the mechanics also results inbetter surface finish, dimensional and geo-metrical accuracy.

P1

Original contourLinearized tool path

Tolerance band

Chord error

P2

P3

Number of NC blocks/sec.

1/SizeTolerance band

Tool Pathvelocity

71

CAMmachine-independent

machine-specific

Postprocessor

CNC Controll

CAM machine-independent

CNC Control

Pol1

Pol3

Pol2

Vpathmax2

Control polygonP1

P2

P3

P4 P5 P6

P7

Vpathmax1Vpath

Vpath

P2 P3 P4 P5 P6 P7 Time

TimeVpathmax2

Vpathmax1

72

Conventional CNC-technology does notknow anything about cutting conditions.CNCs strictly care only about geometry.Today’s NC-programs contains constantvalues for surface and spindle speed.

Within one NC-block the CNC can onlyinterpolate one constant value. This givesa ”step-function” for the changes of feedrate and spindle speed.

These quick and big alterations are alsocreating fluctuating cutting forces and ben-ding of the cutting tool, which gives a bignegative impact on the cutting conditionsand the quality of the workpiece. Theseproblems can however be solved if NURBS-interpolation is applied also for techno-logical commands. Surface and spindlespeed can be programmed with the help of NURBS, which give a very smooth andfavourable change of cutting conditions.

Constant cutting conditions mean succes-sively changing loads on the cutting toolsand are as important as constant amountof stock to remove for each tool in HSMapplications.

NURBS-technology represents a high den-sity of NC-data compared to linear pro-gramming. One NURBS-block represents,at a given tolerance, a big number of con-ventional NC-blocks. This means that theproblems with the high data communicationcapacity and the necessity of short blockcycle time are solved to a big extent.

P0, G0

P2, G2P1, G1

P3, G3

P4, G4

P11, G11

P13, G13

P(u)

P12, G12

P21, G21

P31, G31

P41, G41

P(v)

P¡ = (P0, P1, P2, P3)G¡ = (G0, G1, G2, G3)K¡ = (K0, K1, K2, K3, K4, K5, K6, K7, K8)

P11, G12, P13…P21, G22, P23…P31, G32, P33…. . .. . .. . .

G11, G12, G13…G21, G22, G23…G31, G32, G33…. . .. . .. . .

K11, K12, K13…K21, K22, K23…K31, K32, K33…. . .. . .. . .

Pu,v =

Gu,v =

Ku,v =

73

NC-Blocks

Pro

gram

med

fee

dra

te F

Conventional, Progamming

NURBS-based, Programming and Interpolation

Pro

gram

med

sp

ind

le r

evol

utio

n S

NC-Blocks

• Dramatic changes of cutting conditions• Waste of machine productivity• High tool wear• Limited part quality

NC-Blocks NC-Blocks

F6

F5

F4

F3

F2F1

S4

S3

S2

S1

Pro

gram

med

sp

ind

le R

evol

utio

n S

Pro

gram

med

fee

dra

te F

74

The upper pass on the component is machined with a machine control without sufficient look aheadfunction and it clearly shows that the corners have been cut, compared with the lower pass machinedwith sufficient look ahead function

Look Ahead FunctionIn HSM applications the execution time of aNC-block can sometimes be as low as 1 ms.This is a much shorter time than the reactiontime of the different machine tool functions- mechanical, hydraulic and electronic.

In HSM it is absolutely essential to have alook ahead function with much built ingeometrical intelligence. If there is only aconventional look ahead, that can read afew blocks in advance, the CNC has toslow down and drive the axes at such lowsurface speed so that all changes in thefeed rate can be controlled. This makes ofcourse no HSM applications possible.

An advanced look ahead function must readand check hundreds of blocks in advancein real time and identify/define those caseswhere the surface speed has to be changedor where other actions must be taken.

An advanced look ahead analyses the geo-metry during operation and optimises thesurface speed according to changes in thecurvature. It also controls that the toolpath is within the allowed tolerance band.A look ahead function is a basic softwarefunction in all controls used for HSM. Thedesign, the usefulness and versatility candiffer much depending on concept.

75

Cutting fluid in millingModern cemented carbides, especially coatedcarbides, do not normally require cuttingfluid during machining. GC grades performbetter as regards to tool life and reliabilitywhen used in a dry milling environment.

This is even more valid for cermets, ceramics,cubic boron nitride and diamond.

Today’s high cutting speeds results in avery hot cutting zone. The cutting actiontakes place with the formation of a flowzone, between the tool and the workpiece,with temperatures of around 1000 degreesC or more.

Any cutting fluid that comes in the vicinityof the engaged cutting edges will instanta-neously be converted to steam and havevirtually no cooling effect at all.

The effect of cutting fluid in milling isonly emphasising the temperature varia-tions that take place with the inserts goingin and out of cut. In dry machining varia-tions do take place but within the scope ofwhat the grade has been developed for(maximum utilisation). Adding cuttingfluid will increase variations by cooling thecutting edge while being out of cut. Thesevariations or thermal shocks lead to cyclicstresses and thermal cracking. This ofcourse will result in a premature ending ofthe tool life. The hotter the machiningzone is, the more unsuitable it is to usecutting fluid. Modern carbide grades, cer-mets, ceramics and CBN are designed towithstand constant, high cutting speedsand temperatures.

When using coated milling grades thethickness of the coating layer plays animportant role. A comparison can be madeto the difference in pouring boiling watersimultaneously into a thick-wall and a thin-wall glass to see which cracks, and that ofinserts with thin and thick coatings, withthe application of cutting fluid in milling.

A thin wall or a thin coating lead to lessthermal tensions and stress. Therefore, theglass with thick walls will crack due to thelarge temperature variations between thehot inside and the cold outside. The sametheory goes for an insert with a thick coa-ting. Tool life differences of up to 40%,and in some specific cases even more, arenot unusual, to the advantage of dry milling.

If machining in sticky materials, such aslow carbon steel and stainless steel, has totake place at speeds where built-up edgesare formed, certain precautions need to betaken. The temperature in the cutting zoneshould be either above or below the unsui-table area where built-up edge appears.

Achieving the flow-zone at higher tempe-ratures eliminates the problem. No, orvery small built-up edge is formed. In thelow cutting speed area where the tempera-ture in the cutting zone is lower, cuttingfluid may be applied with less harmfulresults for the tool life.

76

There are a few exceptions when the use of cutting fluid could be “defended” tocertain extents:

• Machining of heat resistant alloys isgenerally done with low cutting speeds.In some operations it is of importanceto use coolant for lubrication and tocool down the component. Specificallyin deep slotting operations.

• Finishing of stainless steel and aluminiumto prevent smearing of small particlesinto the surface texture. In this case thecoolant has a lubricating effect and tosome extent it also helps evacuating thetiny particles.

• Machining of thin walled componentsto prevent geometrical distortion.

• When machining in cast iron and nodularcast iron the coolant collects the materialdust. (The dust can also be collectedwith equipment for vacuum cleaning).

• Flush pallets, components and machineparts free from swarf. (Can also be donewith traditional methods or be eliminatedvia design changes).

• Prevent components and vital machineparts from corrosion.

If milling has to be performed wet, coolantshould be applied copiously and a cementedcarbide grade should be used which isrecommended for use in wet as well as indry conditions. It can either be a moderngrade with a tough substrate having multi-layer coatings. Or a somewhat harder,micro-grain carbide with a thin PVDcoated TiN layer.

Essential savings can be done via dry machining:• Increases in productivity as per above. • Production costs lowered. The cost of

coolant and the disposal of it represent15-20% of the total production costs!

This could be compared to that of cuttingtools, amounting to 4-6% of the pro-duction costs.

• Environmental and health aspects. Acleaner and healthier workshop withbacteria formation and bad smellseliminated.

• No need of maintenance of the coolanttanks and system. It is usually necessaryto make regular stoppages to clean outmachines and coolant equipment.

• Normally a better chip forming takesplace in dry machining.

Cutting fluid in HSMIn conventional machining, when there ismuch time for heat propagation, it cansometimes be necessary to use coolant toprevent excessive heat from being con-ducted into; the workpiece, cutting andholding tool and eventually into themachine spindle. The effects on the appli-cation may be that the tool and the work-piece will extend somewhat and tolerancescan be in danger.

This problem can be solved in differentways. As have been discussed earlier, it ismuch more favourable for the die or mouldaccuracy to split roughing and finishinginto separate machine tools. The heat con-ducted into the workpiece or the spindlein finishing can be neglected. Anothersolution is to use a cutting material thatdoes not conduct heat, such as cermet. Inthis case the main portion of the heat goesout with the chips, even in conventionalmachining.

It may sound trivial, but one of the mainfactors for success in HSM applications isthe total evacuation of chips from the cuttingzone. Avoiding recutting of chips whenworking in hardened steel is absolutelyessential for a predictable tool life of thecutting edges and for a good process security.

77

The second best is to have oil mist underhigh pressure directed to the cutting zone,preferably through the spindle.

Third comes coolant with high pressure(approximately 70 bar or more) and goodflow. Preferably also through the spindle.

If using cemented carbide or solid carbide the difference in tool life between the first and the last alternative may be as much as 50% .

If using cermet, ceramic or cubic boron nitride coolant should not be an option at all.

The best way to ensure a perfect chip evacu-ation is to use compressed air. It should bewell directed to the cutting zone. Absolutelybest is if the machine tool has an option forair through the spindle.

The worst case is ordinary, external coolantsupply, with low pressure and flow.

78

≠ fz fz

There are a wide rangeof different parametersthat make up an insertfor different conditionsand workipece materi-als, different substrateswith different grainsizes, different coa-tings, different angles

and shapes, to mention a few. Let us take ashort look at the most important ones.

Macro-geometryThe macro-geometry decides the type ofrake-angle (�), which determines if it is ageometry for roughing or if it is a geometryfor light cutting. How this effects some ofthe cutting parameters is shown in the table.

If there is a light cutting geometry there isa large rake angle resulting in a sharpercutting edge (1). This cutting edge is not as

strong as an insert with a smaller rakeangle, such as a geometry for roughing (2).Due to this the feed per tooth has to bekept low in comparison (3). However, thesharp cutting edge is favourable in termsof cutting forces which will be low andmachines with limited effect can be used(4). The temperature (5) will also be lowdue to the light cutting action which oftenis an advantage.

Micro-geometryThe edge rounding (ER), size and angle ofthe negative chamfer is decided by themicro-geometry. With larger (ER) or nega-tive chamfer the stronger the cutting edgebecomes and resulting in a possibility touse high feed rates. Large ER and negativechamfer will also produce higher cuttingforces and higher temperature, which maycause plastic deformation of the cuttingedge. If a component with thin walls or

THE INSERT AND ITS PARAMETERS

1

2

3

4

5

� �

79

light cutting action is needed small ER andnegative chamfer should be used. Some examples of ER and negative cham-fer for different materials:

Steel geometries usually have large ER andnegative chamfers to produce a strong cut-ting edge capable of withstanding anyshock impacts when machining steel.

Stainless steel is a work-hardening materialand if an insert with large ER and negativechamfer, such as one for steel millingwhich produces high tempratures, is usedthe workpiece material usually work-har-dens and becomes more difficult to machi-ne when it is time for the second pass.Sharp geometries with small ER and nega-tive chamfer are therefore used to get alight cutting action.

When rough machining cast-iron, strongcutting edges are needed to cope with largedepths of cut and sand inclusions. Thiscalls for large ER and negative chamfer.On the other hand when finishing in cast-iron, e.g. an engine block, the planenessand surface finish is vital. Cast-iron alsohas a tendency of frittering and therefore asharp cutting edge with a small ER andnegative chamfer is needed.

The chart (page 98) shows how differentparameters affects the inserts wear resi-stance to different types of wear mecha-nisms, in terms of substrate content andmicro-geometry.

A wolfram-carbide based insert, usually aP-grade is favourable in terms of withs-tanding abrasion-wear, although, it has litt-le diffusion- and oxidation-wear resistance.

P30

b ⇒ fz min

b

γ

ER

ISO

M

P

K

P20

80

WC

Co

γ

HV3

SizeWC

+ o - + - o

- -/+ -/+ - + o

+ - + + - o

+ - - + - o

- -/+ - - + -

1 2 3 4 5 6

1. Abrasion wear2. Fatique wear (static or dynamic)3. Adhesion wear

4. Plastic deformation5. Chipping/fracture6. Possibility to make a scharp edge

Furthermore it is good in terms of fatigue-wear, but the high content of WC is nega-tive when it comes to adhesion-wear. Toprevent plastic-deformation, a high con-tent of WC is favourable but not in termsof chipping.

High content of cobalt, which is a bindingmaterial in carbide inserts, have somenegative effects on the wear resistance ofinserts. Abrasion-, diffusion- and oxida-tion-wear mechanisms are negatively affec-ted by a high content of Co. Fatigue- andadhesion-wear plus chipping tendenciesare enhanced by cobalt, while plastic-deformation tends to occur more easilywith cobalt as binding material.

The so called g-phase TaC + TiC + NbCalso affects the wear resistance of the insertin certain ways. Modern insert grades havelittle or no g-phase at all. However, g-phase is positive in terms of preventingabrasion-, diffusion-, oxidation-, adhesion-wear and plastic-deformation. While it isnegative for prevention of fatigue andchipping.

A high proportion of hard particles makesthe cemented carbide more wear resistantin that the hardness, HV, and compressivestrength is greater. A high content of bin-ding material Co, makes the insert moretough. High hardness is positive for mostwear mechanisms discussed earlier exceptfor fatigue wear and chipping. The hard-ness has little effect either way in terms ofoxidation wear.

81

The last parameter to be discussed is thesize of the WC grains in the insert substrate.By adjusting the size of the grains in thesubstrate, many different features can beaccomplished even though within the sameinsert grade. This affects the hardness andwear resistance as well as strength andtoughness. Generally, small grains meanshigher hardness, coarse grains more tough-ness. This means that cemented carbide isnot brittle, but has a broad range of possi-bilities within machining. The insert in thewear mechanism example is an insert withcoarse grains. The positive aspects withcoarse grains is, as mentioned earlier,toughness and therefore favourable to pre-vent fatigue- and chipping. The coarsegrains has negative effect on the rest ofthe wear mechanisms featured exceptfor oxidation wear where it makes nodifference either way.

82

PVDPVD (Physical VapourDeposition) is a wellestablished coatingtechnique used mainlyfor coating of highspeed steel, but is alsogood for coating ofcemented carbide,

where a sharp cutting edge is needed.

The process is based on that the coatingmaterial is moved from a material sourceto the substrate through either vapourizationor sputtering. There are several variants ofthese processes as they are used widely byhigh speed steel suppliers. The PVD process

takes place in temperatures around 500degrees C. For instance, titanium is ionizedwith a focused electric beam as energysource, to form a plasma stream. Alongwith nitrogen this is coated on the insert.Normally, a PVD coating is thinner than acomparable CVD coating. With the CVDprocess a thicker coating means improvedwear resistance, especially with aluminiumoxide, up to a thickness of 12 micrones.

CVDCVD (Chemical Vapour Deposition) is amore modern type of coating techniqueenabling multi layer coating and differentlayer thickness from 2-12 microns.

COATING METHODS

CVD PVD

83

Basically, CVD coating is done throughchemical reactions of different gases. In thecase of coating with titanium carbide; hy-drogen, titanium chloride and methane.Inserts are heated to about 1000 degrees C.Like sintering this is a carefully controlledprocess where the carbon content, eitherfree or as h-phase, has to be monitoredthrough an extra carburization stage, beforecoating. Aluminium oxide coating carriedout in a similar way as is titanium nitridecoating using other gases, aluminium-chloride or nitrogen gas, respectively. TheCVD process is well adapted to applymulti layered coatings as the process isrelatively easy to regulate as regards to

various gases. Different types of coatingcan be performed in the same equipment. In the table you can see how differenttypes of coating methods are affecting theinsert positive (+) or negative (-) in termsof withstanding different types of wear.Also shown is how the various types ofcoating can cope with the wear-mechanisms;TiAlN (Titian Aluminium Nitride),TiCN) (Titanium Carbo Nitride), Al2O3(Aluminium Oxide), TiN (TitaniumNitride).

PVD

CVD

MT-CVD

TiAlN

TiN

Ti(C,N)

Al2O3

- + + - + ++ o o + o -+ o o + o -+ o + + - o+ o o o o o++ - +* + - -o o o o o o

* Polished

1 2 3 4 5 6

1. Abrasion wear2. Fatique wear (static or dynamic)3. Adhesion wear

4. Plastic deformation5. Chipping/fracture6. Possibility to make a scharp edge

84

Since steel is the mostcommon material tobe machined withinthe die and mouldarea, the Coromantgrades optimized forsteel milling will beexplained a little bitmore in detail.

For the milling operation that need a verystrong cutting edge, where toughnessdemands are highest, the GC4040 grade(P30-P50) provides a new combination oftoughness and wear resistance. A productof modern coating technology, the gradecopes with the most demanding machiningconditions. The objective has been to achi-eve high edge security primarily at low tomoderate cutting speeds - yet some 25%higher than its predecessor.

GC4040 is an insert grade that will not needfor operators to stand next to the stopbutton or continually stop the cutter worrying about the cutting edges for chip-ping tendencies. If applied correctly, itcopes with strength-demanding steel milling,unstable conditions, vibration tendencies,varying workpiece materials and when theinsert is subjected to high cutting forces.

The 90 degree entering angle in millingleaves insert corners very susceptible tohigh machining stresses. Not only radialforces are high, the entry and exit shock-forces are often severe. To improve theedge security, ensuring a long predictabletool-life, GC4040 is ideal. For the CoroMill290 square shoulder facemill the gradeoffers improvement in performance and

reliability. Also for very demanding opera-tions, such as die and mould making, thegrade means very high edge strength forround insert cutters, such as CoroMill 200.GC4040 can be applied to perform sharplight cuts as well as high feed roughingoperations and is suitable for use with allthree insert geometries L, M and H. Withor without coolant operations (see cuttingfluid in milling page 95). Also suitable for castings and forgings, the grade offers newpossibilities for small batch production tobe performed in a productive and veryreliable way.

Allround performanceGC 4030 is more of a general purpose grade,complementary to 4040. In fact, where 4040optimizes an area characterized by thehighest strength demands, 4030 optimisesmilling of harder steels at higher cuttingspeeds and when low feed rates are involved.There is also a large steel milling applica-tion area, where toughness to a varyingextent is needed, and where both insertgrades can be selected.

GC4030 is capable of higher cutting speeds,offering a higher degree of wear resistancefor operations that are not extreme tough-ness demanding.

This grade is also a product of advancedcoating technology, having a harder insertsubstrate than 4040 but a similar aluminiumoxide coating. GC4030 is especially suitableas a general, basic grade for use with 45degree entering angle, such as in CoroMill245, but also for round insert millingwith CoroMill 200. Dry and wet millingis possible.

Choose the right grade for milling

85

GC4030 is also capable of milling hardersteel types as it has good resistance tothermal cracking. These inserts are excel-lent for milling large workpieces, requiringlong cutting edge engagement times.Maintaining high cutting edge security, itprovides long, predictable tool-life andgenerates good surface finish.

GC4020GC4020 is the High Speed Machining gradefor good conditions and maximum produc-tivity. This grade can be applied in hardand more difficult to machine materialsthat are becoming more and more commonin die and mould making applications,especially when using HSM technology.This means that the inserts in grade GC4020will add the possibility to machine at veryhigh temperatures that occurs when millinghardened steel, up to HRC60, or whenvery high cutting speeds in general steelsare used for max productivity.

The application area for this grade is roughing to semifinishing milling in steelsat fairly good conditions when highestpossible chip removal rate is desired. Insertsin grade GC4020 need to be run at hightemperature e g at elevated speeds and/orin hardened condition up to HRC60, asmentioned previously.

If possible, try to avoid using coolant whenmilling. Usage of coolant will shorten thetool-life and increase the tendency forchipping or breakage of the inserts comparedto dry milling. Usage of coolant gives in-creased fluctuation of temperatures, whichin turn leads to a larger number of thermalcracks. For a grade like GC 4020 it’s im-portant to avoid coolant in order to get theright cutting temperature and to limit thenumber of thermal cracks.

High wear resistanceGC3040 is an odd insert grade in thiscontext as it was primarily developed fornodular cast iron and high tensile ironmilling. However, the grade has proven tobe such a good performer in steel throughits high wear resistance, high temperaturecapability and chemical inertness, that ithas been included in the range of insertsthat are dedicated to optimizing steel milling.

Basic grades for ISO P milling Basic grades for ISO K milling

CT 530Finishing - Dry!

4040Optimal security at a

wide feed range!

3020First choice in gray

cast iron

CC 690

CB50

1025

Max wear resistance!

4030All round with highwear resistance!

Toughness Toughness

Wea

r re

sist

ance

Wea

r re

sist

ance 4020

Sharp edges!

3040

Toughness demandingoperations Perlitic nodularCl, wet milling, vibrations

H13AMilling of

ferritiic NCI

Milling of grey Cl at high speeds

Ra & high vc

3040

86

GC3040 has specially adapted aluminiumoxide coating to mill at high cutting speedsand stand up to the high temperatures ofmilling harder steels.

Sharp cutting edge GC1025 is a specialist insert grade for lightmilling in steels such as SS1672, SS2041and UHB steel grades Orvar and Impaxhigh hard to mention a few. This is mainlya finishing grade which is combined withgeometries to give a sharp cutting edge.Based on fine grain cemented carbide sub-strate, it is PVD coated and can be used inperiphery ground indexable inserts.

The sharp cutting edge means that it makessatisfactory insert engagement into materialalso at lower feed rates and minimizes vibra-tion tendencies in weak workpieces. It isalso good at milling sticky, low carbon steelsas well as super alloy materials.

High surface finishCT530 is a cermet grade capable of genera-ting mirror finishes (P05-P30). This is alight milling finishing insert, for small cut-ting depths but with a wide cutting speedrange. It provides the advantageous long

tool-life with consistent cutting edge per-formance of titanium-based cemented car-bide. It has very high resistance to plasticdeformation and built-up edge formationand has an added suitable application areain the form of wiper insert. Most suitablefor dry conditions, this is an insert forhigh surface finish and accuracy demands.If round inserts in grade CT530 is combinedwith a strong geometry it is also good forlarge ap/ae and intermittent machinging.

The application decides the insert When choosing grade the applicationmust be looked upon as a whole and notjust the workpiece material. In the examp-les it is shown what parameters should beconsidered.

The workpiece (mould) and workpiecematerial is the same for all examples. Butto get the best result for each machiningoperation, different grades and geometrieshas to be used.

Cavity Milling in Orvar Supreme 41 HRC

cutting speed [m|min]

too

l life

[m

in]

100 150 200 250 300

140120

100

80

60

4020

0

GC 4020GC 4030

87

Start values for cutting speed (m/min) at different max chip thickness hex (mm) for ISO P steel milling. (ae= 100 mm with cutter diameter 125 mm)

Material

CMC

01.1

01.2

01.3

01.4

01.5

02.1

02.2

03.11

03.13

03.21

03.22

06.1

06.2

06.3

Specificcuttingforce

kc 1

1500

1600

1700

1800

2000

1700

2000

1950

2150

2900

3100

1400

1600

1950

Hardness

HB

125

150

170

210

300

175

330

200

200

300

380

150

200

200

0.05

463

427

399

349

258

334

198

253

209

181

115

341

271

198

0.15

380

351

328

287

212

274

163

208

172

149

95

280

223

163

0.25

312

288

269

235

174

225

134

171

141

122

78

230

183

134

0.1

481

442

414

362

268

346

206

300

218

187

118

353

280

206

0.2

395

363

340

298

220

284

169

246

179

154

97

290

230

169

0.3

324

298

279

244

181

233

139

202

147

126

80

238

189

139

CT530 GC4020

Material

CMC

01.1

01.2

01.3

01.4

01.5

02.1

02.2

03.11

03.13

03.21

03.22

06.1

06.2

06.3

Specificcuttingforce

kc 1

1500

1600

1700

1800

2000

1700

2000

1950

2150

2900

3100

1400

1600

1950

Hardness

HB

125

150

170

210

300

175

330

200

200

300

380

150

200

200

0.1

356

328

306

268

199

256

153

194

161

139

88

262

208

153

0.2

292

269

252

220

163

210

125

159

132

114

72

215

171

125

0.3

240

221

207

181

134

173

103

131

109

94

59

177

140

103

0.1

302

278

260

228

169

218

130

165

136

118

75

223

177

130

0.2

248

229

214

188

139

179

107

136

112

97

61

183

145

107

0.4

170

154

144

127

94

121

72

91

76

66

41

123

98

72

0.05

334

307

287

252

187

240

143

182

150

131

82

246

195

143

0.1

302

278

260

228

169

218

130

165

136

118

75

223

177

130

0.2

248

229

214

188

139

179

107

134

112

97

61

183

145

107

GC4030 GC4040 GC1025

Dark grey area = hex value

88

For operation one which is face-milling of the component aCoroMill 200 round insert cutteror a CoroMill 245 facemilling cut-ter can be used. Here the machi-ning condition is good, no adaptorsand long tools are needed. Noconsideration of recutting of chipshas to be taken and high cuttingspeed can be used. Taking intoaccount the stable and good condi-tion of the operation an insertgrade with a sharp geometry anda wear resistant grade should beused. The choice would be a gradefor the P20 area.

In the second operation the con-ditions are getting a little bit moreunfavourable with a longer tool,which might mean a tendency forvibrations and recutting of chips.However, the stability and recut-ting of chips is not considered tohave a great effect on the machi-ning in this case and thereforemedium cutting speed can be used.Here an allround geometry couldbe used with a slightly toughergrade than the first operation, pre-ferably within the P30 area.

89

For these three operations the workpiece material is the same and the same cutter type,e.g. a CoroMill 200 cutter can be used. But to get the best machining result three differentgrades and insert geometries are used. The conclusion is that the operation as a wholemust be examined and not just the workpiece material.

The third operation is machiningdeep into the cavity before semi-finishing with a ball nose endmill.The tool overhang is considerable,with a big risk of vibration occuring.Recutting of chips and suddenchanges in feed direction, leadingto a high variation in cutting forces.Low cutting speed has to be usedto counteract the vibration andkeep deflection of the tool as lowas possible. An insert with stronggeometry is called for in this caseand a grade suitable for the P40area. The cutting edge can at thesame time not be too dull, a geometryfor medium machining would bepreferred instead of a geometry forroughing.

90

CoroMill 245Facemilling is one ofthe most commonmilling applicationsand can be performedwith a wide range ofdifferent tools.Facemilling cutterswith 45° or 75° enter-

ing angle, square shoulder milling cutterswith 90° entering angle, round insert millingcutters or even side and face milling cutters.

The most optimized of these cutters interms of ranging from roughing to finishing with the best result and highestproductivity is the 45° degree milling cutter. The CoroMill 245 cutter with 45°entering angle performs many facemillingoperations better than any other tool. The cutter body is produced from hardenedtool steel with a hardness of 45 HRc andall machining is done after hardening. Thisgives the cutter high precision because of

no increase in run-out by local hardening.Furthermore it gives the cutter an evenhardness with no soft zones from localhardening.

The 245 cutter programme for facemillingusing a series of 12 mm square insertscovering a wide application area, fromlight to tough conditions. The inserts,supported by a rigid shim protected cutterbody, can take depth of cut up to 6 mm.The cutter is capable of producing anexcellent surface quality during a long toollife, also when used at high removal rates.Many operations can be fully finished inone pass. The main advantage of 45° enter-ing angle is the reduced chip thickness,which allows the feed per tooth (ƒz) to besubstantially increased. The 45° enteringangle also gives the most favourable direc-tion of cutting forces when machiningwith extended tools. Furthermore, it givesless risk of edge frittering of the workpiece.

CUTTING TOOLS

90

91

A 3 mm thick carbide shim supports theinsert and protects the insert seat in case ofoverloading the insert. The screw mountedsquare inserts are self locating when posi-tioned into the insert seat. The clear-sheargeometry of the insert seats and the com-bination of highly positive in the axialdirection and negative in the radial is ofdistinct advantage particularly with largedepths of cut. High removal rates are easilyachieved with this geometry and unfavou-rable positioning of the cutter becomesless critical.

The series of extra positive insert geo-metries cover all appropriate feed rangesrequired for extreme light operations aswell as for the heavy ones. Wide parallellands generate good surface finish even at high feed rates.

To further increase the surface finish or increase the feed rate with maintainedsurface finish the solution is to use wiperinserts. These provide a much larger flatlength. The flat is located just below theordinary parallel land of the other insertsand wipes the surface smooth, it is a fini-shing cutting edge that has been added tothe cutter. The flat is dimensioned to coverthe feed per revolution. The wiper flat in-sert produces good surface textures evenunder unfavourable conditions and areoften used in short chipping materials suchas grey cast-iron. Wiper inserts are also oftenused in aluminium alloys, in which thedemands on surface finish often are high.

L M H

92

CoroMill® 245 wiper insert- principal function

Surfaceroughness without

wiper insertwith wiper insert

fn1 = bs1 fn2 = bs2 fn = feed/revolution

Feed

bs2bs1

Diameter mm

Max n rpm

Max Vc m/min

32

29000

2915

40

18250

2890

50

16250

2985

63

14400

3365

80

12700

3520

100

11300

3770

125

10100

4320

Maximum rpm and cutting speed Vc

The CoroMilll 245 wiper insert has an 8.2 mm land which allows the feed perrevolution to be increased by up to fourtimes the normal feed, with good surfacequality maintained. Especially for largediameter cutters which can fully utilize the combination of wiper- and millinginserts. Normally it is sufficient to useonly one wiper insert in a cutter.

The CoroMill 245 is optimized for facemilling applications and to machine any material, type of workpiece in anymachine tool.

93

CoroMill 200Round insert cutters can perform a widevariety of milling operations. The reasonfor round inserts being the strongest typeof insert is that the entering and exit anglesvaries, as well as the chip cross sectionvaries depending on the depth of cut. Thistype of cutter has the strongest inserts andis therefore suited for medium and roughmachining. This means that it is easy toachieve high productivity with this typeof cutter, and inspite of the high metalremoval rates round insert cutters oftenhave the best tool-life.

The CoroMill 200 facemilling cutter is avery versatile tool. It is a good choice forgeneral milling as well as for die- andmouldmaking and should be first choicefor roughing and medium operations.The application areas are many for theCoroMill 200; facemilling, endmilling,pocketing, contouring and multi-axis milling are applications that the 200 cutteris well suited for. Lets consider the benefitswith a round inset cutter for each of theseapplication areas.

94

FacingIn normal facemilling applications roundinserts for the most part provide moreeffective cutting edges per insert thanother insert shapes. Round inserts providea chip thinning effect which allows higherfeed rates compared to 90 or even 45degree cutters. It should also be the firstchoice for hardened and heat resistantmaterials. The combination of curved cut-ting edge, negative rake and thickness ofthe insert makes it well suited for millingin such materials.

Contouring, pocketingThe CoroMill 200 insert geometries arewell suited for the typical stamping dieset-up where there are extended over-hangs, chatter and recutting of chips. Thelarge cutter body clearance allows rampingand plunging.

Multi-axis machiningThe new generation of CNC-machines areoften supplied with multi-axis capability,both in programming and set-up.Therefore the need for tools with multi-axis capability. The 200 cutter has moreversatility and a wider range of possiblemovements than any other milling cutter.This makes the cutter ideal for curved sur-face machining, both concave and convex.Plus the capability to perform circularinterpolation in 2- or 3 axes.

95

Cutter bodyThe CoroMill 200 has been robustly desig-ned to cope with high metal removal ratesand difficult materials in a safe way. Thelarge and open chip pockets manages largeamounts of chipflow. Even though thecapability of very heavy machining, thesafety has not been compromised with.The shim protected insert seat efficientlyprotects the cutter body in case of a tooloverload. The cutters are available in dia-meters from Ø 25 mm up to Ø 160 mmwith coarse, close or extra close differentialpitch with insert sizes 10, 12, 16 or 20 mminserts as standard.

InsertsRound inserts means strength and abilityto machine pockets with high productivity.

These milling cutters have often requiredpowerful machines and provided insuffici-ent accuracy. The development towardspositive insert geometries has vastly broa-dened the application area for roundinserts. The extra positive geometry has anadvantageous effect on heat development,vibration tendencies and power require-ments. These inserts have a sharp cuttingedge and positive top rake angle whichenables good chip forming ability and asmooth cutting action.

The different geometries provide extrasafety for the respective applications.

Geometry L for light operations is anextra positive geometry for machining inall materials. The L geometry also createslow cutting forces and can be used forweak workpieces and machine tools, whenvibrations occur. Ground RCHT insert forCoroMill 200 cutters are also suitable forfinishing operations.

Geometry M for medium operations is thepositive geometry for all-round use andbasic insert for most materials. Suitable forsmall to medium size machines and opti-mized performance in soft and stainlesssteel. It can also be used in hardened steelwith lower feed rate.

Geometry H for heavy operations withreinforced cutting edge for safe production.This insert is reliable in operations whenrecutting of chips occur and offers highestpossible feed rate. Power consumption ofthe H geometry is slightly higher, approxi-mately, 10% higher compared with geo-metry M.

L

M

H

96

The facets which all CoroMill 200 insertshave provide distinctive indexing up toeight times which makes it easy to get a

controlled indexing. The centre screwmounting of the inserts facilitates troublefree chip flow and easy mounting.

Fräser-Ø

25/25,4* mm

32/31,75* mm

40/38,1* mm

50/50,8* mm

63/63,5* mm

80/76,2* mm

100/101,6* mm

125/127* mm

160/152,4* mm

200/203,2* mm

250/254* mm

iC 09*

37500

31600

27900

23200

20300

18200

15500

13700

12500

10700

9500

iC 10

37500

30900

26500

22900

19900

17300

15300

13500

11800

10500

9300

iC 12

32100

25900

21900

18800

16200

14000

12300

10900

9500

8400

7500

iC 13*

32300

26400

22800

18600

16100

14400

12200

10700

9700

8300

7400

iC 16

-

26200

21400

18000

15300

13100

11400

10000

8700

7700

6800

iC 19*

-

-

24600

19100

16100

14200

11800

10300

9300

7900

7000

iC 20

-

-

18400

15000

12500

10600

9200

8000

6900

6100

5400

97

CoroMill 390CoroMill 390 is a high positive endmilling,square shoulder and facemilling conceptthat produces, among other things, true 90degree component shoulders. The concepthas been developed to meet customerdemands on all endmilling operationswithin both the roughing and finishingareas. The main focus being on precision,component quality, productivity, versatili-ty and easy handling.

The CoroMill 390 cutter bodies are produ-ced from hardened steel with all machiningcarried out after the hardening process.This method provides the followingadvantages;• no increase in insert run-out from local

hardening • increased fatigue strengthThis in its turn lead to• Highest precision; longer tool life and

better surface quality and dimensionel tolerances

• Longer life of the cutter body

One of the CoroMill 390 features is rela-ted to the inserts main cutting edge whichis not straight. The main cutting edges hasa helical shape in the axial direction and a

convex configuration in the radial. Eachcutter diameter has optimised axial andradial rake angles to ensure 90 degreeshoulder is produced. From this design theconcept produces a shoulder in the work-piece with minimum mismatch even afterseveral axial passes.

The cutter comes with two insert sizes 11 mmand 17 mm. The 11 mm insert cutter areavailable in diameters ranging from 16 mmto 63 mm and the cutters with 17 mminserts have a diameter range of 25 to 80mm. Four insert geometries are availablefor the 390 cutter: E-L is a precisionground geometry for light operations andthe L-geometry, also for light operations.The M-geometry is for general purposeoperations and the H-geometry fordemanding applications.

The maximum recommended rpm andcutting speed vc should be taken inconsideration when using the cutter, asshown in the table.

98

Diameter/Coromant Capto size

Max RPM

Max Vc m/min

16

C4

39 000

1959

20

C4

34600

2173

25

C4

36500

2865

32

C4

31000

3115

32

C5

28000

2813

40

C4/C5

27000

3391

Size - 11 insert Size - 17 insert

Max RPM

Max Vc m/min

40

27000

3391

50

23700

3721

63

20700

4095

80

18200

4572

40

21900

2751

50

19000

2983

63

16500

3264

80

14400

3617

Maximum RPM Coromant Capto

Square shoulder facemills

99

CoroMill 290Traditionally square shoulder milling hasbeen performed by endmills or dedicatedsquare shoulder cutters. The reasons forthat has varied. One of them has been thatfacemilling cutters were not able to machine90° corners, which is often the case whensquare shoulder milling.

The complete CoroMill 290 programmecovers the majority of square shoulderapplications in many modern machiningcentres. The cutter is available in a wideprogramme, comprising coarse and closeas well as extra-close pitched cutters ininsert size, 12 mm.

The main characteristic of Coromill 290 isthe advanced insert geometry and insertswith four cutting edges mounted in shimprotected pockets offering highest possiblesecurity, combined with low cutting forces.

Inserts with advanced chip forming geo-metries have the ideal balance between lowcutting forces and high edge security.

- M is the positive all-round geometry,covering the majority of square shoulderapplications under varying conditions.

- L is the light cutting geometry, designedfor machining with low poweredmachines, fragile workpieces, unstableclamping and for materials requiring asharper cutting edge.

- H is the tough geometry for highestpossible edge security. Inserts with largeparallel land perform exellent surfacefinish even at high feed rates. Insertswith 2.0 mm corner radius give thehighest edge security in roughing ormedium operations, or when machiningunder unstable conditions.

100

These inserts not only provide a sharper,positive cutting edge, they also have chip-forming ability and have carefully designedtransitions between various parts of thegeometry, adding micro strength to thecutting edge. The design of the chipformerreduces contact between chip and edge andcurls the chip, making it more manageableand carrying away more heat from thecutting area.

All the inserts have a 1.6 or 2.1 mm paral-lel land which increases the capability ofproducing better surface finish comparedto an insert with only corner radius. Toobtain the best surface finish the cuttingdata should be selected, whenever possib-le, to give a feed per revolution (ƒn) lessthan the length of the parallel land. A rule of thumb is to use 70% of theparallel land in feed per revolution.

Diameter mm

40

50

63

80

100

125

160

200

250

290-12

21600

18400

15900

13700

12000

10600

9250

8200

7300

Maximum recommended rpm

101

BALL NOSE ENDMILL R216The ball nose endmill 216 is a strong androbust endmill concept. Each cutter bodyhas two effective inserts and each diameteruses the same insert type in both the cent-re and periphery insert seats. The insertdesign gives two cutting edges per insertand the concept is aimed at roughing andsemi-finishing of curved surfaces in machi-ning centres, CNC milling machines and

copy milling machines for die and mouldmaking, aerospace, automotive to name afew. It is possible to feed the tool in alldirections.

There are individual insert sizes for eachcutter diameter and the insert design permitsuse of the same insert type in the peripheryas well as in the centre insert pocket.

Diameter D3

Max. depth of cut, ap

Protection insert ap

Radial rake angle

Axial rake angle

12

10,8

-

0

-10

16

14,4

-

0

-10

20

17,9

-

0

-10

25

22,3

-

0

-10

30

26,9

42

0

-10

32

28,6

-

0

-10

40

35

65

0

-10

50

44

74

0

-10

Cutter body and insert details

20

1216

40

50

323025

Start values - feed/tooth

0,05 0,08 0,10 0,12 0,15 0,15 0,20 0,25

12 16 20 25 30 32 40 50

102

The unique insert geometry makes it pos-sible to drill with the ball nose cutter.However, deviations on the workpiecemay occur at the centre of the cutter.

R

681012,515162025

A

1.41.72.23.03.93.53.63.8

B

0.070.090.120.180.200.220.240.26

The larger diameters of the cutter are alsoavailable with a shank protection insert forperforming heavy duty copy milling.Diameter 30 mm with one insert and dia-meters 40 and 50 mm with two inserts.

103

SOLID CARBIDE ENDMILLSEspecially in finishing the demand is highfor small high performing solid endmills,both 90 degree and ball nose. Well in linewith the modern machining demands thereare several different solid carbide endmillsfor both general and HSM machining avai-lable, in several different grades. Some ofthe cutters are specially designed for HSMand for machining of hardened material upto 63 Hrc.

1020 (TiC,N) is the allround grade mostsuitable for general endmilling in mostmaterials. It is reliable and the wear processis even and predictable.

1010 (TiAIN) is very suitable for machiningof hardened tool steel. The high heat resi-stance capability makes it suitable for dry

machining and allows short machiningtimes and long toollife, demands whenmachining big moulds. For best use ofgrade 1010 special geometries are required.

The substrate for both grades is H10F, amicro grain grade. The toughness beha-viour is very good, which is important inorder to avoid tool breakage and chipping,particularly on sensitive corners. Most ofthe multi fluted endmills have strengthenedcorner geometries for maximum security.

On some of the 1010 cutters there arehelix reduction over the corners and this isto strengthen the cutting edge and preventchipping especially when machining har-dened material. The helix reduction alsoallows tougher cutting data to be used.

104

OVERVIEW OF TOOLS AND OPERATION GUIDELINES

Recommended Applicationendmill

R215.36L Finishing - sidemilling ae < 0.05 - 0.1 x Dc60 degree helix and six cutting edges.

Radial depth of cut max 10% of the diameter Dc.Non drilling version

R215.3x-H 30 degree helix and the number of edges equal to the diameter in mm.

Radial depth of cut max 5% of the diameter.Non drilling version.

R216.34-N Semi - sidemilling ae < 0.25 x DcR216.33-N Three and four edge endmills with 30- and 45 degree helix.

R216.33-N Recommended for side milling in mixed production.

R216.34-N Choose 45 degree helix for smoothest action and best surface finish

Two edge version recommended for long chipping material.

All versions with drilling capability.

105

Roughing - slotting ap and ae < 0.5 x Dc

Two and three edge short version provide good stabilitylowest deflection - also undersized tools are available forkey slot milling.

For deep slots two edge versions are recommended oralternatively create several passes.

45° degree helix for smooth action and to helpchip evacuation.

Recommended for stainles steel.

For heavier copy milling, two edge ball nose endmills are recommended.

All versions have drilling capability.

R216.32-N

R216.32-N

R216.33-N

R216.33-N

R216.33-P

R216.34-N

R216.34-N

R216.42-N

106

Copy milling/High speed milling (HSM)

Two and four edge ball nose endmills for finish milling of deep dies and moulds.

Recommended for all materials.

Two and four edge spherical ball nose endmills forsteep die cavities providing accessibility and a reducedcontact length.

Recommended for depth of cut in finishing - ap/ae = 0.1- 0.2 mm.

Preferably use downmilling and pulling feed direction.

Ball nose and radius versions with rigid shanks, shortcutting length and optimised geometry for reliable semi-finishing at high speeds (HSM).

All tools are centre cutting, however, not recommended for drilling. Recommended operations are circular inter-polation and light ramping.

Tools are designed for dry milling.

Always use tool holders with as low radial runoutas possible; CoroGrip, shrink fit, Coromant Capto,precision ground collet chucks, precision chucks.The radial runout should not exceed 10 �m. Use thestrongest possible tools with high stiffness and bigcore diameter. Try to minimise the tool overhang.

R216.44-L

R216.42-L

R216.42-L

R216.42-LR216.42-L

R216.42-LR216.42-L

R216.42-LR216.42-L

107

DRILLING TOOLS FOR DIES AND MOULDSIn many dies andmoulds there are seve-ral holes to be machi-ned such as; hole forlocation pins, - moun-ting screws, threadedholes and holes forcooling and warmingup. To successfully

machine these holes the right kind of drilland drilling method has to be applied, ran-ging from twisted HSS drills to STS andEjector drills for deep hole drilling.

Ejector

STS

108

Short hole drillingGenerally, short hole drilling is referred to when machining holes with a relativelysmall hole-depth and drill-diameter ratio.At drill diameters up to 30 mm the holedepth can be 5-6 x D, while up to 60 mmit is 4 x D and above 2,5 x D usually is thelimitation. Todays drills can keep closetolerances, down to IT-10.

There are some different alternatives tochoose from when deciding what type ofdrill that should be used for an application;HSS drills, HSS drills tipped with cemen-ted carbide, solid carbide drills, twisted orstraight flute drills with indexable inserts.

When choosing the type of drill, the firstquestion is whether to use a regrindable-or indexable insert drill? Since indexableinsert drills do not cover the smallest dia-meters it is only regrindable drills whichcan be used for small hole applications.Under all circumstances it is good to startlooking at the hole diameter and requiredlength of the hole, to narrow down theselection of tools.

109

Small hole diametersRegrindable drills with Delta geometry isavailable in two different versions over-lapping one another; Delta, and Delta C.In the diameter range covered by Delta C, workpiece material in relation to machine tool capacity will be the deter-mining factor regarding which drill to use.

If the machine tool capacity is good andthe possibility to use high spindle speed isavailable the qualities of the cemented carbide at the Delta C drill should be utilised. However, if the spindle speed isnot high enough the capacity of the DeltaC drill can not be utilised because cementedCarbide needs sufficient cutting speed towork at its best.

110

since they have exchangeable inserts. Thiscost advantage is particularly beneficialwhen machining large series.

We will not discuss larger short hole drillssuch as trepanning drills as these sizes ofholes can easily be made by circular in-terpolation with a round insert millingcutter or an endmill. Using a milling cutterto machine the holes within the mediumsized diameter is also an alternative whichshould be taken in consideration whenchoosing machining method.

Medium sized hole diametersThe diameter range considered as mediumsized is where the Coromant U-drill andDelta drill overlap each other. At highdemands on close tolerances or when thedepth of the hole limits the use of theU-drill (indexable insert drill), the Deltadrill is the only alternative.

On the other hand, when the initial pene-tration surface is not flat, if the hole ispre-drilled, or if cross-drilling must bedone, then the indexable insert drill isthe only option. These drills will providethe lowest cost per machined component,

111

Deep hole drillingDeep hole drilling is something which isa relatively common operation in die andmould making, for instance to machineholes for cooling or warming of the mould.There are some different ways to drill deepholes and the most common for die andmould making are gundrilling, STS andejector drilling.

In the gun drilling system, the cutting fluidis supplied internally through the tool andthe chips are removed through a V-shapedgroove in the shaft. Conventional machineswith sufficiently high spindle speed, coolantsupply (flow and pressure) and a suitablerange of feeds can be modified for gundrilling. However, the best results areobtained with special gun drilling machines.

These should be equipped with a drillbushing (A), a splash guard (B), an oil sup-ply unit (D) and, generally, it is necessaryto support the workpiece with a steady restC. In addition, it is necessary to have a tankwhich provides efficient filtering and cooling(E), plus a pump (F) with sufficient capacityin terms of both pressure and volume.

The gun drill is the only drill which canbe used with the gun drilling system. Gundrilling is primarily used when precision-drilling of small holes has to be performed.It can cope with hole depths up to 100 xthe drill diameter. If additional steady restsare used, it is possible to drill up to 200 xthe drill diameter, provided the capacity ofthe pump is sufficient.

A B CD

E

F F

112

The Ejector system has twin drill tubes.The cutting fluid is pumped in betweenthe inner and the outer tubes. The majorportion of the cutting fluid is led forwardto the drill head while the remainder isforced through a groove in the rear sectionof the inner tube. The negative pressurewhich arises in the front section of theinner tube means that the cutting fluid atthe drill head is sucked out through theinner tube together with the chips. The Ejector system is self-contained andcan be adapted quite easily for most con-ventional machines, machining centres, NCand CNC lathes. The machine should beequipped with a drill bushing (A), innerand outer tubes (B), a vibration damper Cplus a connector with a collet and a sealingsleeve (D). In addition, it is necessary to havea tank with efficient filtering (E) and cooling(F), plus a pump (G) with sufficient capa-city in terms of both pressure and volume.

The drill head is screwed firmly onto theouter tube, which has a four-start squarethread. If the support pads are not in con-tact with the drill bushing another threadstart can be used. The thread starts have a4 x 90 degree positioning.

One clear advantage with gun drilling isthe high quality of the hole achieved,which is crucial for cooling channels in atool. If the quality of the cooling channelsis not good enough the channels can easilybe put out of order due to corrosion.

It is also important that the tolerance ofthe pre-drilled guidance hole is kept closeto get a good result with the gun drill.

113

Connectors are available for both rotatingand non-rotating drills. The connector fora non-rotating drill (1), which is the mostcommon application, has no rotation parts.For rotation drills, a connector is usedwith a mounted and sealed housing aroundthe spindle (2). The outer and inner tubesare attached to the connector by a collet. Asealing sleeve is also used here at the

entrance for the cutting fluid. The colletand the sealing sleeve must be changed fordifferent diameter ranges.

Because the cutting fluid is pumped intothe space between the inner and outer tubes,no seals are required between the work-piece and the drill bushing. Therefore, thesystem is often used with workpieces where

AB C D

E F

G

1

114

sealing problem could arise. This featurealso makes the Ejector system very suitablefor use with interrupted drilling.

The Ejector system can cope with holedepths of up to 100 x the hole diameter whendrilling horizontally and approximately 50x the hole diameter when drilling vertically.

In the STS drilling system, the cuttingfluid is forced in between the drill tubeand the walls of the hole. The cutting fluidshould have sufficient pressure and flow toremove the chips efficiently through thetool and drill tube.

Only special deep hole drilling machinesare used for STS drilling. The machineshould be equipped with an oil pressurehead with a drill bushing and seals (A), adrill tube (B), a vibration damper C and aconnecting chuck (D). In addition, it isnecessary to have a tank which gives effici-ent filtering (E) and cooling (F), plus apump (G) with sufficient capacity in termsof both pressure and volume.

The high cutting fluid pressure and flowmakes the system suitable for use wherematerial with poor chip breaking capacity isto be machined. Hole depths of up to 100 xthe hole diameter can be drilled with STS.

2

115

A B C D

E FG

116

CoroGrip is a holdingsystem that covers allapplications fromsuper-finishing toheavy roughing. Oneholder can clamp alltypes of tools fromfacemills to drills withboth cylindrical,

Whistle notch or Weldon shanks. Standardcollets such as collets for HydroGrip,BIG, Nikken, NT etc., can also be used inthe CoroGrip holders.

The bore and shank (taper) on CoroGripholders are ground to very close tolerances,which enables very small run-out, only0.002 - 0.006 mm at 4 x D. The symmetricalclamping force in the system keeps the lowrun-out for a very long time. The rigiddesign of the holders also keeps the lowrun-out in roughing operations.

It is possible to clamp Weldon/Whistlenotch shanks directly in the holder andalso clamp the shanks half way into theholder. The clamping force in theCoroGrip holders is extremely high andits balanced design makes it perfect forhigh speed machining (<40 000 rpm),which makes the CoroGrip a good alter-native to shrink fit holders.

To obtain the high clamping force anexternal hydraulic pump has to be used.With a pressure of 700 bar, the outer sleeveis pushed up on the taper, when the tool isclamped, and down on the taper when it isunclamped. When the tool is clamped theclamping mechanism is self-locking andthere is no hydraulic pressure in the holderduring machining.

CoroGrip PRECISION-POWER CHUCK

A: Inner body with a small angle taper (around 2 degrees angle).B: Movable sleeve. C: Locking ring. D. Plastic cover ring

A

BD

C

117

It takes less than 20 seconds to change a tool.

Two different pumps can be used when changing tools in a CoroGrip holder; one manual hydraulic pump that is portable and one stationary air-driven pump,which is activated by a foot-pedal.

To connect the pump to the holder an ergonomically designed handle is used.Clamping or unclamping the tool is done by a switch without removing the handle from the holder. When using the manual pump one hand is always free for holding the tool and when using the air-driven pump both hands are free.

The same handle is used for all types and sizes of CoroGrip holders.

118

The picture shows how easy it is to pre-set the tool with the CoroGrip concept.Without any setting screw, you can very easy adjust the length of the tool to arquired measure. Depending on the accuracy of the optical reader, you can set thetool within +/- 3-5 microns.

If the pneumatic pump is used both hands are free to hold and adjust the tool.When it is in exactly right position the foot-pedal is pressed and the tool is fixed.Only the outer sleeve is moving when clamping and unclamping and there are noforces on the pre-setting fixture. This means that all tool changes can be made inthe pre-setter and there is no need of a rigid mounting fixture, which is the case ifpower chucks or outer holders where keys are used for clamping.

119

Shank diameter

12 mm

20 mm

25 mm

32 mm

[Torque Nm]

725093

243181440

421365804

---6511512

Type of holder

Shrink fitHydroGripCoroGrip

Shrink fitHydroGripCoroGrip

Shrink fitHydroGripCoroGrip

Shrink fitHydroGripCoroGrip

Transmission torque comparison [Nm]

120

Extended tools formachining centres arefrequently required tobe able to reach thesurfaces to be machi-ned. With CoromantCapto it is possible tobuild an assemblywith long and short

basic holders, extensions and reductions,so the right length can be achieved. It isvery important to use shortest possibletool overhang in milling operations. Manytimes a small difference in length can bethe difference in working with a good (ormedium productivity) or not working at all.

- With modular tools it is always possible to use optimal tool assemblies and cutting data for best productivity!

COROMANT CAPTOIf solid tools are used, they are often too short or too long. In many cases special solid tools have to be used, whichis expensive and also requires long delivery times.

- Modular tools are built together in minutes!

A special tool with Coromant Captocoupling can also be used in other machi-nes with different spindles. Only a newstandard basic holder is required.

To avoid vibration in a milling or boringoperation a rigid clamping is required. It ismainly the bending moment that is critical,and the most important factor for takingup high bending moment is the clampingforce. Coromant Capto uses centre boltclamping, which is the strongest and chea-pest way to clamp. Normally the clampingforce is double compared with any sidelocking (front clamping) mechanisms. Normally more than 100% productivityincrease can be achieved with centre boltclamping.

121

HSK is a spindle interface and not amodular coupling and should not be mistaken for a modular tool system. Theclamping force is not as great as that pro-duced by Coromant Capto with centrebolt clamping, which is mainly requiredfor milling and boring operations. HSKextensions can, however, be used for lightdrilling and reaming operations, wherethere are low radial forces.

Minimum run-out and guaranteed centre heightPress fit and torque loads spread sym-metrically around the coupling, withoutload peaks, are the reasons for the outstan-ding minimum run-out and centre-height characteristics.

Compare conventional couplings usingone or two keys to transfer torque. Therewill always be a certain amount of play inthe coupling which can cause any of thefollowing situations:

• Asymmetric load situation with highload peak on the key. Causes high surfacepressure and shorter tool-life, as well ashigher run-out.

122

The coupling has the best stability charac-teristics on the market, as a result of:No pins, keys etc. The polygon shapetransmits torque (T) without any looseparts such as pins or keys.

No play in the coupling. The tight pressfit guarantees that there is no play in thecoupling.

Symmetrical loads. Torque load is spreadsymmetrically on the polygon withoutpeaks irrespective of rotation. Thereby thecoupling is self-centring. It also guaranteeslong life of the coupling.

Two face contact/high clamping force. Due to the combination of press fit andhigh clamping force the coupling gets atwo-face contact. A large surface contact

area around the polygon and on the flangetransmits the cutting force F. No loadpeaks. Axial positioning of the cuttingedge will remain constant despite highaxial cutting forces.

Two facecontact

Comparison between holders for clamping of shaft tools

123

Type ofoperation

Transmissiontorque

AccuracyTIR 4 x D[mm]

Suitable forhigh speed

Maintenance

Possibility to use collets

Weldon/whistle-notchholder

Heavy roughing-semi finishing

+++

0.01-0.02

+

None required

No

Collet chuckDin 6499

Roughing -Semi finishing

++

0.01-0.03

+

Cleaning andchangingcollets

Yes

Powerchuck

Heavy roug-hing-finishing

++

0.003-0.010

++

Cleaning andchangingspare parts

Yes

HydroGripHydraulicchuck

Finishing

+

0.003-0.008

++

Non required

Yes

Shrink fit holder

Heavy roug-hing-finishing

+++

0.003-0.006

+++

None required

No

CoroGripHydro-mechanical

Heavy roug-hing -finishing

+++

0.003-0.006

+++

None required

Yes

124

ROUGHING RECOMMENDED METHODRoughing of cavity; downmilling, leaves 1 mm in stock

Cutting tool

Insert

Cutter diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

CoroMill R200-068Q27-12L

RCKT 1204MO-PM GC4030

80 MM

4

4 mm

65% x Dc

250 m/min

995 rpm

0.4 mm/tooth

1592 mm/min

6 00

125125

ROUGHING OF CAVITY RECOMMENDED METHOD 3 axis ramping, contouring, downmilling, leaves 1 mm in stock

Cutting tool

Insert

Cutter diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

CoroMill R200-040Q22-12M

RCKT 1204MO-PM GC4030

52 MM

4

4 mm

65% x Dc

180 m/min

1102 rpm

0.33 mm/tooth

1469 mm/min

1 57

126

ROUGHING OF CAVITYRECOMMENDED METHOD Restmilling

Cutting tool

Insert

Cutter diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

CoroMill R200-020A25-12H

RCKT 1204MO-WM CT530

32 mm

3

2-5 mm

<5 mm

500 m/min

4974 rpm

0.15 mm/tooth

2238 mm/min

1 35

127127

SEMI-FINISHING RECOMMENDED METHOD Contouring, downmilling, leaving 0.2 mm in stock

Cutting tool

Insert

Cutter diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

CoroMill R200-051Q22-12H

RCKT 1204MO-WM CT530

63 mm

5

1 mm

0.8 mm

600 m/min

3032 rpm

0.36 mm/tooth

5457 mm/min

7 30

128

SEMI-FINISHING RECOMMENDED METHOD Contouring, downmilling, leaving 0.2 mm in stock

Cutting tool

Insert

Cutter diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

CoroMill R200-020A25-12H

RCKT 1204MO-WM CT530

32 mm

3

1 mm

0.8 mm

500 m/min

4974 rpm

0.16 mm/tooth

2400 mm/min

1 19

129

ROUGHING COMMON METHOD Roughing of cavity; drilling starting hole

Cutting tool

Insert

Drill diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

Coromant U-drill R416.2-0500L40-21

WCMX 080412R-53 GC4025 (P)

WCMX 080412R-53 GC 1020 (C)

50 mm

2

84 mm

~ Dc mm

150 m/min

955 rpm

0.15 mm/tooth

143 mm/min

0 35

130

ROUGHING COMMON METHODRoughing of cavity; contouring, constant Z-value,downmilling, leaving 1 mm in stock

Cutting tool

Insert

Cutter diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

CoroMill R290-050Q27-12M

R-290.90-12T320M-PM GC4030

50 mm

4

5 mm

65 % x Dc

200 m/min

1273 rpm

0.25 mm/tooth

1273 mm/min

7 43

131

ROUGHING COMMON METHODRoughing of cavity; contouring, downmilling,constant Z-value, leaving 1 mm in stock

Cutting tool

Insert

Cutter diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

Ballnose endmill R216-32B32-070

R-216-32 06 M-M GC1025

32 mm

2

6 mm

6 mm

200 m/min

1989 rpm

0.25 mm/tooth

995 mm/min

6 00

132

ROUGHING COMMON METHODRoughing of cavity; restmilling, copymilling, up- and downmilling (zigzag),leaving 1 mm in stock

Cutting tool

Insert

Cutter diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

Ballnose endmill R216-25B325-60

R-216-25 04 M-M GC1025

25 mm

2

1 mm

1 mm

300 m/min

3820 rpm

0.20 mm/tooth

1528 mm/min

3 35

133

SEMI-FINISHING COMMON METHODContouring, downmilling, leaving 0.2 mm in stock

Cutting tool

Insert

Cutter diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

Ballnose endmill R216-25A25-055

R-216-20 T3 M-M CT530

20 mm

2

1.5 mm

0.8 mm

400 m/min

6367 rpm

0.30 mm/tooth

3820 mm/min

7 46

134

SEMI-FINISHING- COMMON METHOD Contouring, downmilling, leaving 0.2 mm in stock

Cutting tool

Insert

Cutter diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

Ballnose endmill R216-20A25-055

R216-20 T3 M-M CT530

20 mm

2

1.5 mm

0.8 mm

400 m/min

6367 rpm

0.30 mm/tooth

3820 mm/min

6 44

135

FINISHING BOTH METHODS Contouring, up- and downmilling

Cutting tool

Insert

Cutter diameter [ø]

Number of teeth [z]

Depth of cut [ap]

Depth of cut [ae]

Cutting speed [Vc]

Spindle speed [n]

Feed per tooth [ƒz]

Table feed [Vf]

Time [min, sec]

Carbide endmill R216.64-12030-

AK 13L GC1010

-------------

12 mm

4

0.2 mm

0.2 mm

302 m/min

8000 rpm

0.075 mm/tooth

2400 mm/min

1 08 32

136

Recommended method

Roughing:CoroMill 200 - PM 4030ap/ae = 4/26; vc/vf = 180/1592 T 6´ 00”

CoroMill 200 - PM 4030ap/ae = 4/26; vc/vf = 180/1469 T 1´ 57”

CoroMill 200 - WM 530ap/ae = 2-5/<5; vc/vf = 500/2238 T 1´ 57”

Semi-finishing:CoroMill 200 - WM 530ap/ae = 1/0,8; vc/vf = 600/5457 T 7´ 30”

CoroMill 200 - WM 530ap/ae = 1/0,8; vc/vf = 500/2400 T 7´ 30”

Finishing:Ballnose solid carbide endmill - 1010ap/ae = 0,2/0,2; vc/vf = 302/2400 T 49´ 16”

Total machining time: 1h 7´ 37”

Common method

Roughing:Coromant U-drill C1020/P4025ap = 84; vc/vf = 150/143 T 0´ 35”

CoroMill 290 - PM 4030ap/ae = 5/33; vc/vf = 200/1273 T 7´ 43”

Ballnose endmill - MM1025ap/ae = 6/6; vc/vf = 200/995 T 6´ 00”

Ballnose endmill - MM1025ap/ae = 1/1; vc/vf = 300/1528 T 3´ 15”

Semi-finishing:Ballnose endmill - MM 530ap/ae = 1,5/0,8; vc/vf = 400/3820 T 7´ 46”

Ballnose endmill - MM 530ap/ae = 1,5/0,8; vc/vf = 400/1910 T 6´ 44”

Finishing:Ballnose solid carbide endmill - 1010ap/ae = 0,2/0,2; vc/vf = 302/2400 T 8´ 32”

Total machining time: 1h 40´ 55”

The recommended method results in 33% higher productivity and also better surface quality andgeometrical accuracy

137137

MACHINING EXAMPLEMachining of thin walls in aluminium

Roughing Finishing

Tool: Solid carbide Solid carbideTool diameter: 10 mm 8 mmGrade: GC1020 GC 1020Number of teeth [z]: 2 4Cutting speed [Vc]: 628 m/min 603 m/minSpindle speed [n]: 20000 rpm 24000 rpmTable feed [vƒ]: 4800 mm/min 9600 mm/minFeed per tooth [ƒz]: 0.12 mm/tooth 0.1 mm/toothDepth of cut [ap]: 5 mm 2 mmDepth of cut [ae]: 6-10 mm 0.9 mm

The wall thickness is 0.2, 0.3 and 0.4 mm and the height is 20 mm. Themachining is performed by down milling and the first cut on one side is1 mm in axial depth of cut. The following cuts are 2 mm on each side untilthe whole 20 mm is machined. The sequence is also explained more indetail in the HSM chapter in this guide.

138

MACHINING EXAMPLEImproved machining of bumper mould

Finishing operation of a bumper mould where the tool length of 550 mmis an instability factor. The machine used is an Okuma V-MC/MCVA-2with an ISO 50 taper. The material is unalloyed steel.

Old method New method

Tool: Ballnose endmill CoroMill 200Tool diameter: 30 mm 63 mmInsert: HC844 (P30+Tin) GC1025-PLNumber of inserts [z]: 2 4Cutting speed [V c]: 217m/min 593 m/minSpindle speed [n]: 2300 rpm 3000 rpmTable feed [vf]: 2500 mm/min 3000 mm/minFeed per tooth [fz]: 0.54 mm/tooth 0.25/1.0 mm/toothDepth of cut [ap]: 1.0 mm 0.2 mmDepth of cut [ae]: 1.0 mm 0.2 mmMachining time: 50 hours/comp 4 hours/comp

Machining time reduced more than 12 times.

550

139

MACHINING EXAMPLERoughing of cavity in mould for bottles in high alloyed steel

Tool: CoroMill R200-015A20-10HTool diameter: 25 mmInsert: RCKT-10T3MO-KH3040Number of inserts [z]: 3Cutting speed [V c]: 160 m/minSpindle speed [n]: 2000Table feed [vf]: 1500 mm/minFeed per tooth [fz]: 0.25 mm/toothDepth of cut [ap]: 0.8 mmDepth of cut [ae]: 0.8 mmTool-life: 2.5 hoursMachine tool: YASDA, ISO50

140

MACHINING EXAMPLEImproved machining for roughing of grey cast-iron stamping die

Old method New method

Tool: 75 facemilling cutter CoroMill 200,specialTool diameter: 160 mm 180 mmInsert: H 13 A RCKT-2006-MO-KH,3040Number of inserts [z]: 10Cutting speed [V c]: 100 m/min 102 m/minSpindle speed [n]: 210 rpm 160 rpmTable feed [vf]: 800 mm/min 1200 mm/minFeed per tooth [fz]: 0.35 mm/tooth 0.74 mm/toothTool-life: Unpredictable due 162 min to frequent insert failure

The component machined in the example had a lot of sand inclusions anddue to all the cast holes in the component the cutting forces were very unfa-vourable. The entering and exit angles of the inserts was often close to zeroand therefore it was a constant shifting between conventional- and climb-milling where the cut was interrupted. These combined factors call for arigid milling cutter with strong inserts and as the cutting data in the testshows the round insert cutter is clearly the best choice.

3200

2100

141

MACHINING EXAMPLERoughing of pressing die for trucks in tool steel,IMPAX, machine tool OKUMA MCV-A, 30kW

Tool: CoroMill R200-40Q22-12LTool diameter: 44 mmInsert: RCKT-1204MO-WM530Number of inserts [z]: 3Cutting speed [V c]: 295 m/minSpindle speed [n]: 1809 rpmTable feed [vf]: 1628 mm/minFeed per tooth [fz]: 0.30 mm/toothDepth of cut [ap]: 2.5 mmDepth of cut [ae]: 2-4 mmTool-life: 50 min

Rough contouring, downmilling and constant Z-value.

142

MACHINING EXAMPLEFinishing of mould for plastic bin in low alloy steel with a hardness of 29 HRC

Tool: CoroMill R200-028A32-12MTool diameter: 40 mmInsert: RCKT 1204MO-PM,4040Number of inserts [z]: 3Cutting speed [Vc]: 250 m/minSpindle speed [n]: 2000 rpmTable feed [vf]: 2000 mm/minFeed per tooth [fz]: 0.30 mm/toothDepth of cut [ap]: 0.5 mmDepth of cut [ae]: 0.5 mm

The total length of the tool is 400 mm, the component is machined inthree passes without the cutting data being changed to get the surfacefinish required. The two last passes are spring cuts.

143

MACHINING EXAMPLERoughing of die for outer roof to passenger cars in nodular cast-iron

Tool: BNE R216-32B32-070Tool diameter: 32 mmInsert: R216-3206M-M,4040Number of inserts [z]: 2Cutting speed [V c]: 201 m/minSpindle speed [n]: 20000Table feed [vf]: 1000-2000 mm/minFeed per tooth [fz]: 0.25-0.5 mm/toothDepth of cut [ap]: 10-18 mmDepth of cut [ae]: 4-8 mmTool-life: 1.5 hoursMachine tool: SHIN NIPPON KOKI HF-5, ISO50, 40kW

2500

1500

144

MACHINING EXAMPLERoughing, semi-finishing and finishing of cavity in material 2606 with a hardness of 46 HRC

Roughing Semi-finishing

Tool: BNE R216-25B25-060 BNE R216-20B25-050Tool diameter: 25 mm 20 mmInsert: BNE R216-2504M-M,1025 R216-20T3M-M,530Number of inserts [z]: 2 2Cutting speed [Vc]: 120 m/min 200 m/minTable feed [vf]: 600 mm/min 2000 mm/minDepth of cut [ap]: 3 mm 0.8 mmDepth of cut [ae]: 10 mm 0.05 mmMachining time: 31.5 min 5.1 min

FinishingTool: BNE R216,44-12030 -AK26LTool diameter: 12 mmNumber of inserts [z] 4Grade: GC1020Cutting speed [Vc]: 400 m/minTable feed [vf]: 4800 mm/minDepth of cut [ap]: 0.3 mmDepth of cut [ae]: 0.002 mmMachining time: 19 min

Previously the machining time for this operation was 2 hours and only solidcarbide endmills in small diameters were used. With ball nose endmill withindexable inserts and one solid carbide endmill the operation was performedin 55.6 min. None of the tools showed any significant tool wear.

100

40

100

145

MACHINING EXAMPLERoughing of pressing die for trucks in tool steel,IMPAX, machine tool OKUMA MCV-A, 30kW

Tool: R216-20B25-070Tool diameter: 20 mmInsert: R216-20T3M-M,1025Number of inserts [z]: 2Cutting speed [Vc]: 200 m/minSpindle speed [n]: 3183 rpmTable feed [vf]: 1592 mm/minFeed per tooth [fz]: 0.25 mm/toothDepth of cut [ap]: 0.5-3.5 mmDepth of cut [ae]: 2 mmTool-life: 40 min

Rough milling of bottom surface, mixed up- and downmilling. Too low cut-ting speed was used in this case, however no visible wear on the inserts.

146

MACHINING EXAMPLEFinishing of forging die in tool steel with a hardness of 35 HRC

Tool: BNE R216-20B25-50Tool diameter: 20 mmInsert: R216-20T3M-M,1025Number of inserts [z]: 2Cutting speed [Vc]: 138 m/minSpindle speed [n]: 2200 rpmTable feed [vf]: 1550 mm/minFeed per tooth [fz]: 0.5 mm/toothDepth of cut [ap]: 2 mmDepth of cut [ae]: 0.5 mm

147

MACHINING EXAMPLESemi-finishing of pressing die for trucks in tool steel, IMPAX, machine tool OKUMA MCV-A 30 kW

Tool: BNE R216-25B25-080Tool diameter: 25 mmInsert: R216-2504M-M, 1025Number of inserts [z]: 2Cutting speed [Vc]: 300 m/minSpindle speed [n]: 3820 rpmTable feed [vf]: 2292 mm/minFeed per tooth [fz]: 0.30 mm/toothDepth of cut [ap]: 0.5-3.5 mmDepth of cut [ae]: 1 mmTool-life: 2.5 hours

Contouring, up- and downmilling, no visible wear on the inserts.

148

MACHINING EXAMPLEFinishing of mould for bottles in tool steel (RAMAX)

Tool: BNE R216.42-08030AK16L Tool diameter: 8 mmNumber of inserts [z): 2Grade: GC1010Cutting speed [Vc]: 220 m/minSpindle speed [n]: 11700Table feed [vf]: 4200 mm/minFeed per tooth [fz]: 0.18 mm/toothDepth of cut [ap]: 0.1 mmDepth of cut [ae]: 0.14 mmTool-life: 34 piecesMachine tool: YASDA, ISO40

70

150

149

MACHINING EXAMPLESemi-finishing and finishing of mould for electro-spindle in high alloy steel

Semi-finishing Finishing

Tool: BNE R216,42-08030AK16L BNE R216,42-06030AK10LTool diameter: 8 mm 6 mmNumber of inerts [z]: 2 2Grade: GC1010 GC1010Cutting speed [Vc]: 276 m/min 370 m/minSpindle speed [n]: 11000rpm 20000 rpmTable feed [vf]: 1400 mm/min 1600 mm/minFeed per tooth [fz]: 0.06 mm/tooth 0.04 mm/toothDepth of cut [ap]: 0.3 mm 0.2 mmDepth of cut [ae]: 0.5 mm 0.2 mmTool-life: 250 min 600 minMachine tool: Mori Seiki, ISO30

* BNE = Ball Nose Endmill

Finishing

Finishing

Semi-finishing

150

MACHINING EXAMPLESemi-finishing and finishing of die for beer mug in high alloy steel

x

x

Semi-finishing Finishing

Tool: BNE R216.44-08030-19L BNE R216.42-06030AK10LTool diameter: 8 mm 6 mmNumber of inserts [z]: 4 2Grade: GC1010 GC1010Cutting speed [Vc]: 250 m/min 320 m/minSpindle speed [n]: 10000rpm 17200 rpmTable feed [vf]: 2000-2500 mm/min 3000 mm/minFeed per tooth [fz]: 0.05-0.07 mm/tooth 0.07 mm/toothDepth of cut [ap]: 0.2 mm 0.1 mmDepth of cut [ae]: 0.2 mm 0.1 mmTool-life: 1080 min 600 minMachine tool: Mori Seiki, ISO30

* BNE = Ball Nose Endmill

151

MACHINING EXAMPLESlotmilling of inserts for moulds in CALMAX whith a hardness of 56-58 HRC

Tool: BNE R216,33-02045-ACO6P Tool diameter: 12 mmNumber of inserts [z]: 3Grade: GC1020Cutting speed [Vc]: 220 m/minSpindle speed [n]: 15000Table feed [vf]: 1500 mm/minFeed per tooth [fz]: 0.03 mm/toothDepth of cut [ap]: 0,04 mmDepth of cut [ae]: 2 mmTool-life: Not established 160 pieces without wearMachine tool: Deckel Maho DMU 50V

Previously the application was performed by spark erosion and themachining time was 1.5 hours per component. With HSM the machiningtime per component is 5 min. The slot is machined in 48 passes.

152

MACHINING EXAMPLEMachining of moulds for ventilation, mounted in the dashboard in cars. The workpiece material is low alloy steel with a hardness of 50-52 HRC

Tool: BNE R216.42-04030-AKO5LTool diameter: 4 mmGrade: GC1010Cutting speed [Vc]: 150 m/minSpindle speed [n]: 12000Table feed [vf]: 1200 mm/minFeed per tooth [fz]: 0.05 mm/toothDepth of cut [ap]: 0.1 mmDepth of cut [ae]: 0.1 mmTool-life: 15-18 hoursMachine tool: MIKRON VCP 710

There are eight moulds in each set and with the EDM method previouslyused it took 100 hours to produce a set, with the HSM machine this timehas been reduced to 40 hours.

153

MACHINING EXAMPLESemi-finishing of thermoplastic mould

Tool: CoroMill 390R390-025B25-11M

Tool diameter: 25 mmInsert: R390-11T308M-PM,1025Number of inserts [z]: 3Cutting speed [Vc]: 162 m/minSpindle speed [n]: 2068 rpmTable feed [vf]: 3050 mm/minFeed per tooth [fz]: 0,49 mm/toothDepth of cut [ap]: 0.5 mmDepth of cut [ae]: 25 mmTool-life: 1.5 hours

154

MACHINING EXAMPLERough machining of moulds to the rear section of the fenders for trucks

Tool: CoroMill 390 R390-040B32-11M

Tool diameter: 40 mmInsert: R390-11T308M-PM,1025Number of inserts [z]: 4Cutting speed [Vc]: 143 m/minSpindle speed [n]: 1140 rpmTable feed [vf]: 780 mm/minFeed per tooth [fz]: 0.17 mm/toothDepth of cut [ap]: 16 mmDepth of cut [ae]: 3 mmTool-life: 45 min/edge

Only downmilling is used in this application, when up-milling was used thetool-life was reduced by 50%.

155

MACHINING EXAMPLESlotmilling of die in P20 steel

Tool: CoroMill 390R390-020B20-11M

Tool diameter: 20 mmInsert: R390-11T308M-PM,1025Number of inserts [z]: 3Cutting speed [Vc]: 185 m/minSpindle speed [n]: 3000 rpmTable feed [vf]: 1829 mm/minFeed per tooth [fz]: 0,2 mm/toothDepth of cut [ap]: 3 mmDepth of cut [ae]: 20 mm

exempel 18

156

MACHINING EXAMPLEFacemilling of mould for doors in forged non-alloy steel

Tool: CoroMill 245R245-125Q40-12L

Tool diameter: 125 mmInsert: R245-12T3E-PL,4030Number of inserts [z]: 6Cutting speed [Vc]: 270 m/minTable feed [vf]: 965 mm/minFeed per tooth [fz]: 0.19 mm/toothDepth of cut [ap]: 2 mmDepth of cut [ae]: 95 mmTool-life: 2 components

157

MACHINING EXAMPLEFacemilling of pressing die in cast-iron

Tool: CoroMill 245R245-160Q40-12L

Tool diameter: 160 mmInsert: R245-12T3M-KM,3020Number of inserts [z]: 7Cutting speed [Vc]: 221 m/minSpindle speed [n]: 440 rpmTable feed [vf]: 700 mm/minFeed per tooth [fz]: 0,23 mm/toothDepth of cut [ap]: 5 mmDepth of cut [ae]: 120 mm

158

MACHINING EXAMPLERough facemilling of die in P20 steel

Tool: CoroMill 245R245-160Q40-12M

Tool diameter: 152 mmInsert: R245-12T3M-PH,4040Number of inserts [z]: 10Cutting speed [Vc]: 110 m/minSpindle speed [n]: 500 rpmTable feed [vf]: 914 mm/minFeed per tooth [fz]: 0,18 mm/toothDepth of cut [ap]: 5 mmDepth of cut [ae]: 106 mm

ex 21

159

MACHINING EXAMPLEDrilling through holes for guide pins in 30 mm thick plates for mould bases in low carbon steel

Tool: Coromant UR416.2-0165L20-31

Tool diameter: 16.5 mmInsert: LCMX 020204C-53Cutting speed [Vc]: 62 m/minSpindle speed [n]: 1200 rpmFeed [vn]: 0.1 mm/revDepth of cut [ap]: 30 mmDepth of cut [ae]: 16,5 mm

160

MACHINING EXAMPLEDrilling holes in mould bases in non-alloy steel

Tool: Coromant UR416.2-0260L32-41

Tool diameter: 26 mmInsert: WCMX 05 0308R-53,1020 (centre)

WCMX 05 0308R-53,3040 (periphery)Cutting speed [Vc]: 150 m/minSpindle speed [n]: 1850 rpmFeed [fn]: 0.10 mm/revDepth of cut [ap]: 102 mmDepth of cut [ae]: 26 mm

The reason for using two different insert grades is the difference in cuttingspeed between the centre and the periphery of the drill. The GC 1020grade have good wear resistance and toughness at low to moderatecutting speeds. While the GC4025 grade has good wear resistance andedge security at high cutting speed.

161

MACHINING EXAMPLEDrilling of holes for guide pins in mould bases in non-alloy steel

Tool: Coromant U R416.0240L 25-41Tool diameter: 24 mmInsert: LCMX 04 0308-53.1020Cutting speed [Vc]: 113 m/minSpindle speed [n]: 1499 rpmFeed [fn]: 0,12 mm/rev

Previously high speed steel drills were used for this application and whenchanged to the Coromant U drill the feed has been increased by 360%and the cutting speed by 514 %. The U drill has also been equipped withan adaptor to facilitate internal cutting fluid. Which is of great importancefor chip evacuation when drilling.

162

MACHINING EXAMPLEDeep hole drilling of mould base, change of method from Gun drilling to STS, resulting in significant savings. The workpiece material is low alloy steel with a hardness of 300 HB

New method Old method

Tool: Sandvik Coromant Gun drillSingle Tube System420.6-0224 DO.093

Tool diameter: 23.8 mm 23.8 mmInsert: 67 TIN/TIC,N C4Cutting speed [V c]: 60 m/min 62 m/minTable feed [vf]: 165 mm/min 38 mm/minDepth of hole: 401.6 mm 401.6 mmMachining time/comp: 5.25 hours 22.75 hours

The change to STS drilling in this case resulted in a saving of 1050 USdollar per componet.

163

MACHINING EXAMPLEDeep hole drilling (cross hole drilling) change of drilling method from Gun drilling to STS-drilling

New method Old method

Tool: Sandvik Coromant Gun drillSingle Tube System 420.6-0513 D1.156

Tool diameter: 29.4 mm 29.4 mmInsert: 67 TIN/TIC,N C4

(cross hole adapter)Cutting speed [Vc]: 55 m/min 62 m/minTable feed [vf]: 122 mm/min 31.8 mm/minDepth of hole: 762 mm (1 cross) 762 mm (1 cross)Machining time/comp: 8.1 hours 31.18 hours

The change to STS drilling in this case resulted in a saving of 1269 USdollar per componet. The saving is calculated on cross hole only.

164

MACHINING EXAMPLEDeep hole drilling of waterlines in moulds, change of drilling method from Gun drilling to STS drilling. Workpiece material; low alloy steel with a hardness of 350 HB

New method Old method

Tool: Sandvik Coromant Gun drillSingle Tube System 420.6-0514

Tool diameter: 29.4 mm 29.4 mmInsert: 70 70Cutting speed [Vc]: 62 m/min 62 m/minTable feed [vf]: 139.7 mm/min 25.4 mm/minDepth of hole: 914 mm (1 cross) 914 mm (1 cross)Machining time/comp: 3.3 hours 18 hours

The change to STS drilling in this case resulted in a saving of 882 USdollar per component.

914

TROUBLE SHOOTING

165

Cause

Weak clamping

Axially weak workpiece

Action

Establish the direction of the cuttingforces and position the material support accordingly.

Try to improve the clamping generally.

Reduce the cutting forces by reducingthe radial and axial cutting depth.

Choose a milling cutter with a coarsepitch and positive design.

Choose positive inserts with a smallcorner radius and small parallel flats.

Where possible, choose an insertgrade with a thin coating and a sharpcutting edge. If necessary, choose anuncoated insert grade.

Avoid machining where the work-piece has poor support against cut-ting forces.

The first choice is a square shouldercutter with positive inserts.

Choose an L-geometry with a sharpcutting edge and a large clearanceangle which produces low cutting forces.

Try to reduce the axial cutting forcesby reducing the axial cutting depth,as well as using positive inserts witha small corner radius, small parallellands and sharp cutting edges.

Problem: The machining results are affected by vibration

166

Cause

Large overhang either on thespindle or the tool

Square shoulder milling witha radially weak spindle

Uneven table feed.

Action

Always use a coarse and a differen-tially pitched milling cutter.

Balance the cutting forces axiallyand radially. Use a 45 degree enteringangle, large corner radius or roundinserts.

Use maximum sized extensions,tapered if possible and/or tuned.

Use heavy metal shanks.

Use inserts with a light cuttinggeometry.

Try to reduce the overhang, everymillimetre counts!

Reduce rpm but not feed/tooth.

Reduce ap/ae if necessary.

Choose the smallest possible millingcutter diameter in order to obtain themost favourable entering angle. Thesmaller diameter the milling cutter hasthe smaller the radial cutting forceswill be.

Choose positive and light cuttinggeometries.

Try up milling.

Try up milling.

Look at the possibility of adjusting thefeed screw on conventional machines.Adjust the lock screw or replace theball screw on CNC-machines.

Problem: The machining results are affected by vibration

167

Problem

VibrationsThe most common problems• High noise• Uneven wear and chipping• Corner damage• Short toollife• Bad surface finish

Chip jammingCritical in full slotting especially in longchipping materials. Can cause cornerdamage, edge chipping and breakage.Recutting of chips reduces toollife.

Unacceptable workpiece/surfaceGeometrical and dimensional tolerances

Surface finish and burr generation

Tool breakage or chippingOften caused by overloading of tool orchip jamming.

Smearing and build up edgeEspecially austenitic materials, titaniumand aluminum

High wearMostly due to unfavourable cutting condi-tions or very abrasive materials

Possible solution

- Reduce tool run-out max 0,02mm(HSM max. 0.01)

- Minimize tool outstick!! 20% outstickreduction reduces the tool deflectionby 50%!!

- Improve stability in clamping- If possible use larger tool diameter- Use a tool with less teeth- Divide cutting depth in several steps

and increase ƒz- Use a tool with high helix- Increase ƒz- Reduce Vc

- Use 2 or maximum 3-fluted tools- Divide cutting depth into several passes- Try high helix tools- Use well directed compressed air to

evacuate chips- Reduce ƒz

- Use upmilling in finishing- Reduce radial depth of cut- Reduce tool outstick- In finish-copying in steep pockets use

BNE with spherical design to reducedeflection.

- Check runout in holder- Avoid Vibrations- Reduce fz and/or increase vc- Check wear on the tool

- Reduce cutting depth- Reduce tool outstick- Use largest possible tool diameter- Avoid Chip jamming- Reduce ƒz- Evacuate chips to avoid recutting!

- Use coolant or oilmist- Increase vc

- Use downmilling- Increase fz- Check recommended cutting data- Avoid Vibrations- Avoid recutting of chips

TROUBLE SHOOTING - SOLID CARBIDE ENDMILLS

168

Tool wear

Rapid flank wear causing poor suface texture or inconsis-tency in tolerance.

Possible cause

Cutting speed too high or insufficient wear resistance.

Possible remedy

Select a more wear resi-stant grade.

For work-hardeningmaterials, select a smaller entering angle.

Reduce cutting speedwhen machining heatresistant material.

FLANK WEARTool wear

Excessive crater wear causing a weakenededge and poor surface finish.

Possible cause

Excessive cutting temperatures and pressure on the top face of inserts.

Possible remedy

First, reduce cuttingspeed to obtain a lowertemperature andsecondly, the feed.

Select a more wear resistant grade.

Select a positive insert geometry

CRATER WEAR

Tool wear

Plastic deformation ofedge, depression orflank impression, leadingto poor chip control poorsurface finish and insertbreakage.

Possible cause

Cutting temperature and pressure too high.

Possible remedy

Select a more wear resi-stant grade, which is harder.

• Reduce cutting speed.

• Reduce feed.

PLASTIC DEFORMATION

Tool wear

Built-up edge causingpoor surface finish andcutting edge chipping,when the BUE is tornaway.

Possible cause

Cutting zone temperatureis too low.

Negative cutting geometry.

Very sticky material,such as low-carbonsteel, stainless steelsand aluminium.

Possible remedy

Increase cutting speed.Change to a more suitable coated grade.

Select a positive geometry insert.

BUILT-UP EDGE

TROUBLE SHOOTINGTool Wear

169

Tool wear

Small cracks perpen-dicular to the cuttingedge causing chippingand poor surface finish.

Possible cause

Excessive temperature variations.

Intermittent machining.

Varying coolant supply.

Possible remedy

Select a tougher insertgrade.

Coolant should be applied copiously or not at all.

THERMAL CRACKS

Tool wear

Small cutting edge chipping leading to poorsurface texture andexcessive flank wear.

Possible cause

Cutting edge too brittle.

Insert edge too weak.

Built-up edge has beenformed.

Possible remedy

Select tougher grade.

Select an insert with a stronger cutting edge.

Increase cutting speed. Select a positive geometry.

Reduce feed at beginning of cut.

Improve stability.

CHIPPING

NOTCH WEAREDGE FRACTURE

Tool wear

Notch wear causing poorsurface texture and riskof edge breakage.

Possible cause

Cutting speed too highor insufficient wear resi-stance.

Possible remedy

Select a more wear resi-stant grade.

For work-hardening materials, select a smaller entering angle.

Reduce cutting speed when machining heatresistant material.

Tool wear

Damages not only theinsert but can also ruinthe shim and workpiece.

Possible cause

Excessive tool wear.Grade and geometry tooweak.

Excessive load on theinsert.

Built-up edge has beenformed.

Possible remedy

Reduce feed and/or depth of cut.

Select a stronger geometry, preferably asingle sided insert.

Select a thicker/largerinsert and tougher grade.

Improve stability.

170

Metal Cutting formulas

TECHNICAL DATA

Vc = � x Dc x n1000

Cutting speed, Vc (m/min)

Ve = � x De x n1000

Effective cuttingspeed Ve (m/min)

n = 1000 x Vc� x Dc

Revolutions perminute, n (rev/min)

Feed per minute,vf (mm/min)

vf = fz x n x zn

fz = Vf(zn x n)

Feed per tooth, fz (mm/tooth)

Tc = lmvf

Cutting time, Tc (min)

Metal removalrate, Q (cm3/min) Q = ap x ae x vf

1000

Pc =ap x ae x Vf x kc

60 x 106 x �Net power at spindle, Pc (kW)

Mc =ƒn x � Dc

2 x kc

4000

Torque at spindle, Mc(Nm)

hm =sin �r x 180 x ae x fz

� x Dc x arcsin ( ae )Dc

Average chip thickness(mm) when, ae/Dc ≥ 0,1

Metal Cutting terminology and units

Designations according to ISO Unit

ae = Radial depth of cut mmap = Axial depth of cut mmar = Radial depth of cut

for side and facemills mmDe = Diameter of tool at

a given depth of cut mmDc = Diameter of tool mmDm = Machined diameter -

turning mmfn = Feed per revolution mm/revfz = Feed per tooth mm/zhm = Average chip thickness mmkc = Specific cutting force N/mm2

lm = Machined length mmn = Spindle speed

(Revolutions per minute)RPMMc = Torqe NmPc = Net power kWQ = Metal removal rate cm3/minVc = Cutting speed m/minVf = Feed per minute mm/min Zc = Number of effective

teeth in tool piecesZn = Number of teeth in tool pieces�mt = Efficiency

kc = kc1 x hm-mc

Pc =ap x ae x Vf x K

100 000Approximate power consumption(for K-value seepage 189)

Specific cuttingforce (N/mm2)

171171

ISO DescriptionCMCNo.

ae/Dc=0,8

fz=0,1 fz=0,2 fz=0,4

ae/Dc=0,4

fz=0,1 fz=0,2 fz=0,4

ae/Dc=0,2

fz=0,1 fz=0,2 fz=0,4

01.1 5.7 4.8 4.0 6.2 5.2 4.4 6.8 5.7 4.801.2 6.1 5.1 4.3 6.6 5.6 4.7 7.2 6.1 5.101.3 6.5 5.4 4.6 7.1 5.9 5.0 7.7 6.5 5.401.4 6.9 5.8 4.8 7.5 6.3 5.3 8.2 6.9 5.801.5 7.6 6.4 5.4 8.3 7.0 5.9 9.1 7.6 6.4

02.1 6.5 5.4 4.6 7.1 5.9 5.0 7.7 6.5 5.402.2 7.6 6.4 5.4 8.3 7.0 5.9 9.1 7.6 6.4

03.11 7.4 6.2 5.3 8.1 6.8 5.7 8.8 7.4 6.203.13 8.2 6.9 5.8 8.9 7.5 6.3 9.7 8.2 6.903.21 11.0 9.3 7.8 12.0 10.1 8.5 13.1 11.0 9.303.22 11.8 9.9 8.4 12.9 10.8 9.1 14.0 11.8 9.9

06.1 5.3 4.5 3.8 5.8 4.9 4.1 6.3 5.3 4.506.2 6.1 5.1 4.3 6.6 5.6 4.7 7.2 6.1 5.106.3 7.4 6.2 5.3 8.1 6.8 5.7 8.8 7.4 6.2

05.11 6.2 5.4 4.7 6.7 5.8 5.0 7.2 6.2 5.405.12 9.7 8.4 7.2 10.4 9.0 7.8 11.2 9.7 8.405.13 8.0 6.9 5.9 8.6 7.4 6.4 9.2 8.0 6.9

05.21 6.9 6.0 5.2 7.4 6.4 5.6 8.0 6.9 6.005.22 9.7 8.4 7.2 10.4 9.0 7.8 11.2 9.7 8.4

05.51 6.9 6.0 5.2 7.4 6.4 5.6 8.0 6.9 6.005.52 8.3 7.2 6.2 8.9 7.7 6.7 9.6 8.3 7.2

15.11 6.5 5.4 4.6 7.1 5.9 5.0 7.7 6.5 5.415.12 9.5 8.0 6.7 10.4 8.7 7.3 11.3 9.5 8.015.13 8.0 6.7 5.7 8.7 7.3 6.2 9.5 8.0 6.7

15.21 6.9 5.8 4.8 7.5 6.3 5.3 8.2 6.9 5.815.22 9.5 8.0 6.7 10.4 8.7 7.3 11.3 9.5 8.015.51 6.9 5.8 4.8 7.5 6.3 5.3 8.2 6.9 5.815.52 8.4 7.0 9.1 7.7 10.0 8.4

20.11 9.1 7.7 10.0 8.4 10.9 9.120.12 9.5 8.0 10.4 8.7 11.3 9.5

20.21 10.1 8.5 11.0 9.3 12.0 10.120.22 11.0 9.3 12.0 10.1 13.1 11.020.24 11.4 9.6 12.5 10.5 13.6 11.4

20.31 10.3 8.6 11.2 9.4 12.2 10.320.32 11.4 9.6 12.5 10.5 13.6 11.420.33 11.8 9.9 12.9 10.8 14.0 11.8

23.1 4.7 4.0 5.1 4.4 5.5 4.723.21 5.1 4.3 5.5 4.7 6.0 5.123.22 5.1 4.3 5.5 4.7 6.0 5.1

04.1 16.0 13.5 17.4 14.7 19.0 16.0

10.1 9.0 7.4 9.9 8.2 10.9 9.0

07.1 3.3 2.7 2.2 3.6 3.0 2.4 4.0 3.3 2.707.2 3.7 3.0 2.5 4.1 3.3 2.8 4.5 3.7 3.0

08.1 3.7 3.0 2.5 4.1 3.3 2.8 4.5 3.7 3.008.2 4.5 3.7 3.1 5.0 4.1 3.4 5.5 4.5 3.7

09.1 3.7 3.0 2.5 4.1 3.3 2.8 4.5 3.7 3.009.2 5.5 4.6 6.1 5.0 6.7 5.5

30.11 1.5 1.3 1.7 1.4 1.8 1.5

30.12 2.5 2.1 2.7 2.3 2.9 2.5

30.21 2.3 1.9 2.5 2.1 2.7 2.330.22 2.7 2.2 2.9 2.4 3.2 2.7

30.3 1.3 1.1 1.5 1.2 1.6 1.3

30.41 2.7 2.2 2.9 2.4 3.2 2.730.42 2.7 2.2 2.9 2.4 3.2 2.733.1 2.1 1.8 2.3 1.9 2.5 2.133.2 2.1 1.8 2.3 1.9 2.5 2.133.3 5.1 4.3 5.6 4.7 6.1 5.1

P

M

S

H

K

N

Unalloyed

Low-alloy(alloying elements ≤5%)

High-alloy(alloying elements ≤5%)

AnnealedHardened tool steel

Non-hardenedHardened and tempered

Castings UnalloyedLow-alloy, alloying elements ≤5%High-alloy, alloying elements >5%

Non-hardenedPH-hardenedHardened

Non-hardenedPH-hardenedHardened

Annealed or solution treatedAged or solution treated and aged

Hardened and tempered

Non-hardenedPH-hardened

Non-weldable ≥0,05%CWeldable <0,05%C

C = 0,10–0,25%C = 0,25–0,55%C = 0,55–0,80%

Steel

Stainless steel

Stainless steel – cast

Heat resistant super alloys

Ferritic/Martensitic

Ferritic/Martensitic

Heat resistant super alloys

Annealed or solution treatedAged or solution treated and agedCast or cast and aged

NIckel base

Annealed or solution treatedSolution treated and agedCast or cast and aged

Cobalt base

Commercial pure (99,5% Ti)α, near α and α+β alloys, annealedα+β alloys in aged cond. β alloys, annealed oraged

Titanium alloys

Extra hard steelHard steel

Cast or cast and agedChilled cast iron

Ferritic (short chipping)Pearlitic (long chipping)

Malleable cast iron

Low tensile strengthHigh tensile strength

Grey cast iron

FerriticPearlitic

Nodular SG iron

Wrought or wrought and aged

Austenitic

Non-hardenedPH-hardened

Austenitic

Non-weldable ≥0,05%CWeldable <0,05%C

Austenitic-Ferritic(Duplex)

Austenitic-Ferritic(Duplex)

Cast, non-agingCast or cast and aged

Aluminium alloys

Wrought or wrought and coldworked, non-agingAluminium alloys

Cast, 13–15% SiCast, 16–22% Si

Aluminium alloys

Free cutting alloys, ≥1% PbBrass, leaded bronzes, ≤ 1% PbBronze and non-leaded copper incl. electrolyticcopper

Copper and copper alloys

1)Calculated with an efficiency ηmt = 0,8

CONSTANT K FOR USE IN POWER REQUIREMENT CALCULATION 1)

172

FACEMILLING, SQUARE SHOULDER FACEMILLING AND SLOTTING WITH SIDE AND FACEMILLING

P 01.101.201.301.401.5

02.102.202.2

03.1103.1303.2103.22

06.106.206.3

C = 0,10 – 0,25%C = 0,25 – 0,55%C = 0,55 – 0,80%

1500 125 0,251600 150 0,251700 170 0,251800 210 0,252000 300 0,25

1700 175 0,252000 275 0,252300 350 0,25

1950 200 0,252150 200 0,252900 300 0,253100 380 0,25

1400 150 0,251600 200 0,251950 200 0,25

1800 200 0,212800 330 0,212300 330 0,21

2000 200 0,212800 330 0,21

2000 230 0,212400 260 0,21

1700 200 0,252500 330 0,252100 330 0,25

1800 200 0,252500 330 0,25

1800 230 0,252200 260 0,25

2400 200 0,252500 280 0,25

2650 250 0,252900 350 0,253000 320 0,25

2700 200 0,253000 300 0,253100 320 0,25

1300 400 0,231400 950 0,231400 1050 0,23

M

20.1120.12

20.2120.2220.24

20.3120.3220.33

23.123.2123.22

05.1105.1205.13

05.2105.22

05.5105.52

15.1115.1215.13

15.2115.22

15.5115.52

ISO

N/mm2 HB mc

ISO

N/mm2 HB mc

N/mm2 HB mc

-S

Rm2)

4020 4030

0,1– 0,2– 0,3 0,1– 0,2– 0,3

2030 2040

1025 H10F

0,1– 0,15– 0,2 0,1– 0,15– 0,2

490– 405– 330 365– 295– 245440– 360– 295 325– 265– 220415– 340– 280 305– 255– 205365– 295– 245 265– 220– 180265– 220– 180 195– 165– 135

345– 285– 230 255– 210– 170245– 195– 165 180– 145– 120195– 160– 130 145– 115– 95

295– 245– 200 195– 155– 130215– 175– 145 160– 130– 105185– 155– 125 140– 115– 95115– 95– 75 85– 70– 55

350– 285– 235 260– 215– 175275– 225– 185 205– 170– 140205– 165– 135 150– 125– 100

240– 190– 155 235– 190– 155170– 135– 105 165– 130– 105175– 140– 155 175– 135– 110

235– 185– 150 200– 160– 125165– 130– 105 155– 125– 100

195– 155– 125 165– 135– 105165– 130– 105 135– 105– 85

215– 170– 135 210– 170– 135145– 115– 95 145– 115– 90160– 125– 105 160– 125– 100

225– 175– 145 190– 155– 125145– 115– 95 145– 85– 90

185– 145– 115 155– 125– 100150– 120– 95 125– 100– 80

65– 55– 55 55– 50– 4746– 43– 40 40– 37– 35

60– 55– 50 50– 48– 4537– 34– 32 32– 30– 2746– 42– 39 40– 37– 34

25– 22– 20 22– 19– 1718– 16– 14 15– 14– 1216– 14– 13 14– 13– 12

130– 120– 110 115– 105– 9565– 65– 55 55– 55– 5055– 50– 48 49– 45– 42

0,05– 0,15– 0,25 0,1– 0,2– 0,3

UnalloyedLow-alloy (alloying elements ≤ 5%)High-alloy, alloying elements >5%)

Non-hardenedPH-hardenedHardened

AusteniticPH-hardened

Unalloyed

Austenitic

Titanium alloys1)

Non-weldable ≥ 0,05%CWeldable <0,05%CAustenitic-ferritic (Duplex)

Annealed or solution treatedAged or solution treated and aged

Annealed or solution treatedAged or solution treated and agedCast or cast and aged

Heat resistant super alloys

Non-weldable ≥ 0,05%CWeldable <0,05%C

Austenitic-ferritic(Duplex)

Iron base

Nickel base

Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo.

Basic grades

Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo.

Basic grades

Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo.

Basic grades

Non-hardenedPH-hardened

Austenitic

Annealed or solution treatedSolution treated and agedCast or cast and aged

Stainless steel – Cast

Ferritic/martensitic

Cobalt base

Commercial pure (99,5% Ti)α, near α and α+β alloys, annealedα+β alloys in aged cond., β alloys, annealedor aged

1) 45–60° entering angle, positive cutting geometry and coolant should be used.2) Rm = ultimate tensile strength measured in MPa.

Non-hardenedPH-hardenedHardened

Ferritic/martensitic

Stainless steel

Non-hardenedHardened and tempered

AnnealedHardened tool steel

Low-alloy (alloying elements ≤ 5%)

High-alloy (alloying elements >5%)

Steel

Castings

100 mm 125 mm

173

4040 1025 3040 530 SM30

0,1– 0,2– 0,4 0,05– 0,1– 0,2 0,05– 0,1– 0,2 0,1– 0,2– 0,4 0,1– 0,2– 0,4

4040 1025 530 4030

H13A

0,1– 0,2– 0,4 0,1– 0,15– 0,2 0,1– 0,15– 0,2 0,1– 0,2– 0,3

0,1– 0,15– 0,2

305– 225– 170 340– 305– 255275– 225– 155 305– 275– 225260– 215– 145 285– 260– 215225– 185– 125 250– 225– 185165– 135– 95 185– 165– 135

215– 175– 120 235– 215– 175155– 125– 85 165– 155– 125125– 100– 65 135– 125– 100

165– 135– 90 180– 165– 135135– 110– 75 150– 135– 110115– 95– 65 130– 115– 95

75– 60– 41 80– 75– 60

220– 180– 120 245– 220– 180175– 145– 95 195– 175– 145125– 105– 70 140– 125– 105

385– 315– 260 425– 385– 350350– 285– 235 385– 350– 315330– 270– 220 365– 325– 295285– 235– 195 315– 285– 260215– 175– 145 235– 210– 195

275– 225– 185 300– 275– 245190– 155– 130 210– 190– 175155– 125– 105 170– 155– 140

205– 170– 145 225– 205– 185170– 140– 115 185– 170– 155145– 120– 100 165– 150– 13595– 75– 65 105– 95– 85

275– 225– 185 305– 275– 250220– 180– 145 245– 220– 200160– 135– 110 175– 160– 145

265– 225– 165235– 205– 150225– 195– 145195– 165– 125145– 125– 90

185– 160– 115130– 115– 85105– 90– 65

140– 120– 85115– 100– 75105– 85– 65

65– 55– 41

190– 165– 120150– 130– 95110– 95– 70

200– 160– 105 210– 185– 165115– 90– 55 120– 105– 95115– 95– 60 125– 110– 100

185– 145– 95 195– 175– 155110– 85– 55 115– 105– 90

180– 145– 95 190– 170– 155160– 125– 85 170– 150– 135

180– 145– 95 190– 170– 15090– 70– 46 95– 85– 75

100– 80– 50 105– 95– 85

180– 145– 95 190– 170– 15090– 75– 46 95– 85– 75

135– 105– 65 135– 125– 110135– 105– 65 140– 125– 115

285– 255– 225 245– 195– 115165– 145– 130 140– 115– 90170– 155– 135 145– 115– 95

265– 235– 215 – – –155– 140– 125 – –

260– 235– 205 – – –230– 205– 185 – – –

255– 230– 205 255– 180– 145125– 115– 105 110– 90– 70145– 125– 115 125– 100– 80

255– 230– 205 – – –125– 115– 105 – – –

190– 170– 150 – – –195– 175– 155 – – –

60– 55– 5044– 41– 38

55– 55– 4935– 33– 3044– 41– 38

23– 21– 1817– 15– 1316– 14– 13

125– 115– 10565– 60– 5555– 49– 46

Basic grades

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)

Cutting speed, vc m/min

Basic grades

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)

Cutting speed, vc m/min

Basic grades

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)

Cutting speed, vc m/min

174

ISO

N/mm2 HB mc

800 130 0,28900 230 0,28

900 180 0,281100 245 0,28

900 160 0,281350 250 0,28

4200 59 HRC 0,25

2200 400 0,28

K

04.1

10.1

07.107.2

08.108.2

09.109.2

30.11

30.12

30.2130.22

30.3

30.4130.42

33.133.233.3

-H

-N

0,07– 0,1– 0,12 0,07– 0,12– 0,2

4020 3040

N/mm2 HB mc

N/mm2 HB mc

0,1– 0,15– 0,2 0,1– 0,15– 0,2

H10 CD10

400 60

650 100

600 75 0,25700 90 0,25

350 30

700 130700 130

550 110 0,25550 90

1350 100 0,25

3020 3040

0,1– 0,2– 0,3 0,1– 0,2– 0,4

265– 215– 180 240– 195– 135220– 180– 145 195– 165– 110

290– 235– 195 260– 215– 145235– 190– 155 210– 170– 115

180– 145– 125 165– 135– 90165– 135– 115 150– 125– 85

65– 55– 48 47– 41– 33

125– 110– 90 90– 75– 65

935– 870– 805 1875– 1740– 1615

845– 785– 725 1695– 1565– 1455

940– 870– 805 1880– 1745– 1615845– 785– 725 1695– 1570– 1455

945– 875– 810 1890– 1755– 1625

375– 350– 325 755– 700– 645285– 265– 245 565– 525– 485

470– 435– 405 945– 875– 810470– 435– 405 940– 875– 805325– 305– 285 655– 610– 565

100 mm 125 mm Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo.

Hardened and tempered

Ferritic (short chipping)Pearlitic (long chipping)

Low tensile strengthHigh tensile strength

Extra hard steel

Malleable cast iron

Grey cast iron

Chilled cast iron

FerriticPearlitic

Nodular cast iron

Cast or cast and aged

BASIC GRADES

Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo.

BASIC GRADES

Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo

BASIC GRADES

175

4030 4040 H13A 690 CB50

1025 530 CB50

530 H13A 1025

0,1– 0,2– 0,4 0,1– 0,2– 0,4 0,1– 0,2– 0,4 0,1– 0,2– 0,3 0,1– 0,15– 0,2

0,07– 0,1– 0,12 0,07– 0,1– 0,12 0,07– 0,12– 0,2

0,1– 0,15– 0,2 0,1– 0,15– 0,2 0,1– 0,15– 0,2

215– 175– 115 195– 160– 105175– 145– 95 160– 130– 85

230– 190– 125 215– 175– 115185– 155– 105 170– 135– 95

145– 120– 80 135– 105– 75135– 110– 75 125– 100– 65

120– 105– 75 545– 445– 36595– 85– 65 455– 370– 305

130– 110– 85 595– 485– 400105– 90– 65 475– 395– 325

80– 70– 50 375– 305– 25575– 65– 48 345– 285– 235

– –– –

845– 725– 365675– 575– 305

– –495– 420– 360

41– 37– 35 80– 55– 70

75– 70– 65 155– 140– 135

160– 140– 115

305– 265– 215

1035– 955– 885 750– 695– 645

930– 865– 800 675– 625– 580

1035– 955– 885 750– 695– 645930– 865– 800 675– 625– 580

1040– 965– 895 755– 700– 650

415– 385– 355 300– 280– 260310– 285– 265 225– 210– 195

515– 480– 445 375– 350– 325515– 480– 445 375– 345– 325365– 335– 310 265– 245– 225

985– 915– 845

885– 825– 765

985– 915– 845890– 825– 765

995– 920– 855

395– 365– 340295– 275– 255

5495– 455– 425495– 455– 425345– 320– 295

BASIC GRADES

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)

Cutting speed, vc m/min

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)

Cutting speed, vc m/min

BASIC GRADES

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)

Cutting speed, vc m/min

BASIC GRADES

176

ENDMILLING

P 01.101.201.301.401.5

02.102.202.2

03.1103.1303.2103.22

06.106.206.3

C = 0,10 – 0,25%C = 0,25 – 0,55%C = 0,55 – 0,80%

1500 125 0,251600 150 0,251700 170 0,251800 210 0,252000 300 0,25

1700 175 0,252000 275 0,252300 350 0,25

1950 200 0,252150 200 0,252900 300 0,253100 380 0,25

1400 150 0,251600 200 0,251950 200 0,25

1800 200 0,212800 330 0,212300 330 0,21

2000 200 0,212800 330 0,21

2000 230 0,212400 260 0,21

1700 200 0,252500 330 0,252100 330 0,25

1800 200 0,252500 330 0,25

1800 230 0,252200 260 0,25

M 05.1105.1205.13

05.2105.22

05.5105.52

15.1115.1215.13

15.2115.22

15.5115.52

ISO

N/mm2 HB mc

ISO

N/mm2 HB mc

N/mm2 HB mc

-S

Rm2)

4020 4030

0,1– 0,2– 0,3 0,05– 0,1– 0,15

2030 2040

0,05– 0,15– 0,25 0,1– 0,2– 0,3

1025 H10F

0,05– 0,1– 0,15 0,05– 0,1– 0,15

490– 405– 330 430– 425– 415440– 360– 295 385– 380– 375415– 340– 280 365– 355– 350365– 295– 245 320– 315– 305265– 220– 180 235– 230– 225

345– 285– 230 305– 295– 290245– 195– 165 215– 215– 205195– 160– 130 175– 165– 165

295– 245– 200 230– 225– 220245– 175– 145 190– 185– 185185– 155– 125 165– 165– 155115– 95– 75 105– 100– 100

350– 285– 235 310– 305– 295275– 225– 185 245– 240– 235205– 165– 135 180– 175– 175

25 mm10 mm

240– 190– 155 235– 190– 155170– 135– 105 165– 130– 105175– 140– 115 175– 135– 110

235– 185– 150 200– 160– 125165– 130– 105 155– 125– 100

195– 155– 125 165– 135– 105165– 130– 105 135– 105– 85

215– 170– 135 210– 170– 135145– 115– 95 145– 115– 90160– 125– 105 160– 125– 100

225– 175– 145 190– 155– 125145– 115– 95 145– 115– 90

185– 145– 115 155– 125– 100150– 120– 95 125– 100– 80

2400 200 0,252500 280 0,25

2650 250 0,252900 350 0,253000 320 0,25

2700 200 0,253000 300 0,253100 320 0,25

1300 400 0,231400 950 0,231400 1050 0,23

20.1120.12

20.2120.2220.24

20.3120.3220.33

23.123.2123.22

70– 70– 65 65– 60– 6055– 50– 50 46– 45– 45

65– 65– 65 60– 55– 5542– 42– 41 36– 36– 3550– 50– 50 45– 44– 44

30– 29– 29 26– 26– 2521– 21– 20 19– 18– 1820– 19– 19 18– 17– 17

145– 145– 145 130– 125– 12575– 75– 75 65– 65– 6565– 65– 60 55– 55– 55

Non-hardenedHardened and tempered

AnnealedHardened tool steel

UnalloyedLow-alloy (alloying elements ≤ 5%)High-alloy, alloying elements >5%)

Non-hardenedPH-hardenedHardened

Non-hardenedPH-hardenedHardened

AusteniticPH-hardened

Commercial pure (99,5% Ti)α, near α and α+β alloys, annealedα+β alloys in aged cond., β alloys, annealedor aged

Unalloyed

Low-alloy (alloying elements ≤ 5%)

Castings

Ferritic/martensitic

Austenitic

Titanium alloys1)

1) 45–60° entering angle, positive cutting geometry and coolant should be used.2) Rm = ultimate tensile strength measured in MPa.

Non-weldable ≥ 0,05%CWeldable <0,05%CAustenitic-ferritic (Duplex)

Annealed or solution treatedAged or solution treated and aged

Annealed or solution treatedAged or solution treated and agedCast or cast and aged

Annealed or solution treatedSolution treated and agedCast or cast and aged

Heat resistant super alloys

Non-weldable ≥ 0,05%CWeldable <0,05%C

Austenitic-ferritic(Duplex)

Iron base

Nickel base

Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo.

Basic grades

Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo.

Basic grades

Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo.

Basic grades

Cobalt base

Non-hardenedPH-hardened

Austenitic

High-alloy (alloying elements >5%)

Stainless steel

Steel

Stainless steel – Cast

177

4040 1025 3040 530 SM30

0,05– 0,1– 0,15 0,05– 0,15– 0,25 0,05– 0,1– 0,15 0,05– 0,11– 0,2 0,08–0,15–0,25

4040 1025 530 4030

365– 350– 335 365– 350– 335330– 315– 305 330– 315– 305310– 295– 285 310– 295– 285275– 260– 250 275– 260– 250200– 195– 185 200– 195– 185

255– 245– 235 255– 245– 235180– 175– 165 180– 175– 165145– 140– 135 145– 140– 135

195– 185– 175 195– 185– 175160– 155– 145 160– 155– 145140– 135– 130 140– 135– 13085– 85– 80 85– 85– 80

265– 250– 240 265– 250– 240205– 200– 190 205– 200– 190155– 145– 140 155– 145– 140

465– 350– 335 510– 495– 475415– 315– 305 460– 450– 430395– 295– 285 435– 425– 405345– 260– 245 375– 370– 355255– 195– 185 275– 275– 260

325– 245– 235 355– 350– 335225– 175– 165 250– 255– 235185– 140– 135 205– 195– 190

245– 185– 175 270– 265– 255205– 155– 145 225– 220– 210175– 135– 130 195– 190– 185110– 85– 80 125– 120– 115

330– 250– 240 365– 355– 340265– 200– 190 290– 285– 275195– 145– 140 215– 205– 195

300– 295– 285270– 265– 255255– 245– 240225– 215– 210165– 160– 155

210– 205– 195145– 145– 140120– 115– 115

160– 155– 150135– 130– 125115– 115– 110

75– 70– 65

215– 210– 205170– 165– 160125– 125– 115

0,05– 0,12– 0,2 0,05– 0,12– 0,2 0,05– 0,1– 0,15 0,05– 0,1– 0,15

245– 235– 225 255– 245– 235135– 135– 125 145– 140– 135145– 140– 135 150– 145– 140

225– 220– 210 235– 230– 220135– 125– 125 140– 135– 130

220– 215– 205 235– 225– 215195– 190– 185 205– 200– 190

220– 215– 205 230– 225– 215110– 105– 100 115– 110– 105125– 115– 115 125– 125– 115

220– 215– 205 230– 225– 215110– 105– 105 115– 110– 105

165– 155– 150 170– 165– 155165– 160– 155 175– 165– 160

350– 340– 335 305– 295– 285195– 195– 185 170– 165– 165210– 200– 195 175– 175– 170

325– 315– 310 – –190– 185– 180 – –

315– 310– 300 – –280– 275– 265 – –

315– 305– 300 275– 265– 260155– 155– 145 135– 345– 130175– 170– 165 150– 145– 145

315– 305– 300 –155– 155– 150 – –

230– 225– 220 – –235– 230– 225 – –

H13A

0,05– 0,1– 0,15

65– 65– 6550– 49– 48

65– 65– 6540– 40– 3950– 49– 49

28– 28– 2720– 20– 1920– 19– 19

145– 140– 13575– 75– 7060– 55– 55

Basic grades

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)Feed, fn mm/r

Cutting speed, vc m/min

Basic grades

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)

Cutting speed, vc m/min

Basic grades

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)

Cutting speed, vc m/min

178

Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo.

Wrought or wrought and coldworked,non-aging

Wrought or wrought and aged

Cast, non-agingCast or cast and aged

Free cutting alloys, ≥1% PbBrass, leaded bronzes, ≤1% PbBronze and non-leadad copper incl.electrolytic copper

Aluminium alloys

Aluminium alloys

Copper and copper alloys

BASIC GRADES

Cast, 13–15% SiCast, 16–22% Si

Aluminium alloys

Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo.

BASIC GRADES

Feed, fz or hex

Cutting speed, vc m/min

HardnessBrinell

Specificcuttingforcekc 1

MaterialCMCNo

BASIC GRADES

ISO

N/mm2 HB mc

3040 4030

0,1– 0,2– 0,3 0,1– 0,2– 0,325 mm10 mm

800 130 0,28900 230 0,28

900 180 0,281100 245 0,28

900 160 0,281350 250 0,28

K07.107.2

08.108.2

09.109.2

0,07– 0,1– 0,12 0,07– 0,1– 0,12

280– 265– 255 245– 235– 225230– 220– 210 205– 195– 185

305– 290– 275 270– 255– 245245– 235– 225 215– 205– 195

190– 185– 175 170– 165– 155175– 170– 160 155– 150– 145

4020 3040

4200 59 HRC 0,25

2200 400 0,28

04.1

10.1

30.11

30.12

30.2130.22

30.3

30.4130.42

33.133.233.3

-H

-N

N/mm2 HB mc

N/mm2 HB mc

0,05– 0,1– 0,15 0,05– 0,1– 0,15

H10F H13A

400 60

650 100

600 75 0,25700 90 0,25

350 30

700 130700 130

550 110 0,25550 90

1350 100 0,25

95– 90– 90 55– 55– 55

175– 175– 175 105– 100– 100

1075– 1055– 1035 860– 845– 830

965– 955– 935 775– 760– 745

1075– 1065– 1040 860– 845– 830970– 955– 935 775– 765– 750

1085– 1065– 1045 865– 850– 835

435– 425– 415 345– 340– 335325– 315– 315 260– 255– 250

540– 530– 520 430– 425– 415535– 530– 520 430– 425– 415375– 370– 365 300– 295– 290

Hardened and temperedHardened and tempered

Low tensile strengthHigh tensile strength

Extra hard steelHard steel

Malleable cast iron

Grey cast iron

Chilled cast iron

FerriticPearlitic

Nodular cst iron

Cast or cast and aged

Ferritic (short chipping)Pearlitic (long chipping)

179

4040 H13A

1025

530 1025

0,07- 0,1- 0,12

0,05– 0,1– 0,15 0,05– 0,1– 0,15

BASIC GRADES

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)

Cutting speed, vc m/min

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)

Cutting speed, vc m/min

BASIC GRADES

Feed/tooth (fz , mm/tooth) or max chip thickness (hex, mm)

Cutting speed, vc m/min

BASIC GRADES

0,1– 0,2– 0,3 0,05– 0,15– 0,25

225– 215– 205 135– 135– 125185– 175– 170 115– 110– 105

245– 235– 225 150– 145– 140195– 185– 180 120– 115– 110

155– 145– 140 95– 90– 85145– 135– 130 85– 85– 80

47– 46– 46

90– 85– 85

1185– 1165– 1145 1125– 1110– 1090

1165– 1045– 1030 1025– 1000– 985

1185– 1165– 1145 1130– 1110– 10901165– 1045– 1030 1015– 1000– 985

1190– 1170– 1150 1135– 1115– 1095

475– 465– 460 455– 445– 435355– 350– 345 340– 335– 330

595– 585– 575 565– 555– 545595– 585– 575 565– 555– 545415– 405– 400 395– 385– 380

180

SOLID ENDMILLSGeneral purpose milling with grades GC1010 and GC1020

R216.32-...N 1020

R216.33-...N 1020

R216.34-...N 1020

R216.33-...P 1020

R216.35-...N 1020

R215.36-...L 1020

R215.3X-...H 1010

ISO HB

P 01.1 125 200–350 125–22001.2 150 180–250 120–19002.1 175 140–240 90–16002.2 330 120–200 80–12003.11 200 140–190 90–130

M 05.111) 200 90–160 40– 9005.211) 200 80–120 50– 9005.511) 230 60– 90 40– 6020.22 350 40– 50 20– 3023.22 350 50– 80 50– 60

K 04 HRC55 40– 70 30– 5004 HRC63 30– 50 -07.1 130 170–250 130–19007.2 230 130–190 100–13009.1 160 200–300 130–19009.2 250 150–200 100–14008.1 180 150–220 100–15030.22 90 1000 1000

ae ≤ 0,1 × Dc

ap = Dc

ap × ae = 0,5 × Dc

vf = fz × n × zn

vc =n × π × Dc

1000

n = vc × 1000

π × Dc

ae

n

Dc

vf

0,25 × vf

Dcmm

2 0,01–0,023 0,01–0,024 0,02–0,045 0,03–0,066 0,03–0,07

7 0,04–0,088 0,05–0,099 0,07–0,10

10 0,07–0,1212 0,08–0,13

14 0,08–0,1416 0,09–0,1518 0,10–0,1620 0,10–0,1625 0,10–0,16

Dcmm

2 0,005–0,0153 0,01–0,024 0,015–0,035 0,02–0,036 0,02–0,04

7 0,02–0,048 0,03–0,0459 0,03–0,045

10 0,035–0,0512 0,035–0,06

14 0,04–0,0716 0,05–0,0818 0,06–0,0820 0,06–0,0825 0,06–0,09

mm/min

m/min

Materials

CMCNo

Cutting speedvc m/min

Cutting speedvc m/min

Roughing – slottingFinishing

Unalloyed steel

Low alloy steel

High alloy steel

Stainless steel

Heat resistant alloysTitanium alloys

Hard steel

Malleable cast iron

Cast iron

Nodular SG iron

Aluminium alloys (cast)

Calculations1) For ramping and drilling

in stainless steel

0,8 × vc0,15 × vf

Only for hardened steel 55–63 HRC.Max ae = 0,05 x Dc.Reduce fz to 40%.

Feed/toothfz mm/z

Feed/toothfz mm/z

rpm

Table feed

Cutting speed

Spindle speed

181

SOLID ENDMILLS High speed machining (HSM) with grade GC1010

ISO HB

P 01.1 125 300–50001.2 150 250–45002.1 175 200–40002.2 330 180–33003.11 200 200–330

M 05.11 200 150–20005.21 200 120–17005.51 230 100–15020.22 350 40– 7023.22 350 70–120

K 04 HRC55 150–25004 HRC63 90–15007.1 130 200–45007.2 230 300–45009.1 160 400–50009.2 250 200–35008.1 180 300–50030.22 90 1000

Dc

ap ≤ 0,1 × Dc

ae < 0,3 × Dc

R216.22-...L 1010

R216.24-...L 1010

Dc mm

3 0,03–0,044 0,04–0,075 0,05–0,096 0,05–0,10

8 0,06–0,1110 0,07–0,1212 0,08–0,1316 0,09–0,16

ae

n

Dc

vf

≤ 0,1 × Dc

vf = fz × n × zn

vc =n × π × Dc

1000

n = vc × 1000

π × Dc

Materials

CMCNo Cutting speed

vc m/min

Unalloyed steel

Low alloy steel

High alloy steel

Stainless steel

Heat resistant alloysTitanium alloys

Hard steel

Malleable cast iron

Cast iron

Nodular SG iron

Aluminium alloys (cast)

Feed/toothfz mm/z

Calculations

mm/min

m/min

rpm

Table feed

Cutting speed

Spindle speed

182

SOLID ENDMILLS Copy milling – high speed machining (HSM), grades GC1010 and GC1020

ISO HB

P 01.1 125 300–500 240–40001.2 150 250–450 200–36002.1 175 200–400 160–32002.2 330 180–330 140–26003.11 200 200–330 160–260

M 05.11 200 150–200 120–16005.21 200 120–170 100–14005.51 230 100–150 80–12020.22 350 40– 70 30– 6023.22 350 70–120 50– 90

K 04 HRC55 150–250 120–20004 HRC63 90–150 70–12007.1 130 200–450 160–36007.2 230 300–450 240–36009.1 160 400–500 320–40009.2 250 200–350 160–28008.1 180 300–500 240–40030.22 90 1000 800

ap ≤ 0,05 × Dc

Dc mm

2 0,015–0,0203 0,03 –0,044 0,04 –0,075 0,05 –0,096 0,05 –0,10

7 0,06 –0,108 0,06 –0,119 0,06 –0,12

10 0,07 –0,1212 0,08 –0,13

14 0,08 –0,1516 0,09 –0,1618 0,09 –0,1620 0,09 –0,16

De = 2 √ ap(Dc – ap)

Dc

De

ve

ap

vf = fz × n × zn

ve =n × π × De

1000

n = ve × 1000

π × Dc

R216.42-...L 1010

R216.42-...H 1010

R216.62-...L 1010

R216.64-...L 100

R216.42-...L 1010

R216.42-...N 1020

R216.44-...L 1020

R216.44-...L 1010

Materials

CMCNo

Effectivecutting speedvc m/min

Effectivecutting speedvc m/min

Unalloyed steel

Low alloy steel

High alloy steel

Stainless steel

Heat resistant alloysTitanium alloys

Hard steel

Malleable cast iron

Cast iron

Nodular SG iron

Aluminium alloys (cast)

Calculations

Feed per toothfz mm/z

Coromant gradeGC1010

Coromant gradeGC1020

mm/min

m/min

rpm

Table feed

Resultant cutting speed

Spindle speed

Effective cutting diameter

183

ISO CoromantMaterialClassifi-cation(CMC)

Country

Great Britain

Standard

Sweden USA Germany France Italy Spain Japan

P

BS EN SS AISI/SAE W.-nr. DIN AFNOR UNI UNF JIS

01.1 080M15 - 1350 1015 1.0401 C15 CC12 C15C16 F.111 -01.1 050A20 2C 1450 1020 1.0402 C22 CC20 C20C21 F.112 -01.2 060A35 - 1550 1035 1.0501 C35 CC35 C35 F.113 -01.2 080M46 - 1650 1045 1.0503 C45 CC45 C45 F.114 -01.3 070M55 - 1655 1055 1.0535 C55 - C55 - -01.3 080A62 43D - 1060 1.0601 C60 CC55 C60 - -01.1 230M07 - 1912 1213 1.0715 9SMn28 S250 CF9SMn28 11SMn28 SUM2201.1 - - 1914 12L13 1.0718 9SMnPb28 S250Pb CF9SMnPb28 11SMnPb28 SUM22L01.1 - - - - 1.0722 10SPb20 10PbF2 CF10SPb20 10SPb20 -01.2 212M36 8M 1957 1140 1.0726 35S20 35MF4 - F210G -01.1 240M07 1B - 1215 1.0736 9SMn36 S 300 CF9SMn36 12SMn35 -01.1 - - 1926 12L14 1.0737 9SMnPb36 S300Pb CF9SMnPb36 12SMnP35 -02.1/02.2 250A53 45 2085 9255 1.0904 55Si7 55S7 55Si8 56Si7 -02.1/02.2 - - - 9262 1.0961 60SiCr7 60SC7 60SiCr8 60SiCr8 -01.1 080M15 32C 1370 1015 1.1141 Ck15 XC12 C16 C15K S15C01.2 150M36 15 - 1039 1.1157 40Mn4 35M5 - - -01.1 - - – 1025 1.1158 Ck25 - - - S25C01.2 – – 2120 1335 1.1167 36MN5 40M5 – 36Mn5 SMn438(H)01.2 150M28 14A - 1330 1.1170 28Mn6 20M5 C28Mn - SCMn101.2 060A35 - 1572 1035 1.1183 Cf35 XC38TS C36 - S35C01.2 080M46 - 1672 1045 1.1191 Ck45 XC42 C45 C45K S45C01.3 070M55 - - 1055 1.1203 Ck55 XC55 C50 C55K S55C01.2 060A52 - 1674 1050 1.1213 Cf53 XC48TS C53 - S50C01.3 080A62 43D 1678 1060 1.1221 Ck60 XC60 C60 - S58C06.33 Z120M12 - - - 1.3401 G-X120Mn12 Z120M12 XG120Mn12 X120Mn12 SCMnH/102.1/02.2 534A99 31 2258 52100 1.3505 100Cr6 100C6 100Cr6 F.131 SUJ202.1/02.2 1501-240 - 2912 ASTM A204Gr.A 1.5415 15Mo3 15D3 16Mo3KW 16Mo3 -02.1/02.2 1503-245-420 - - 4520 1.5423 16Mo5 - 16Mo5 16Mo5 -02.1/02.2 - - - ASTM A350LF5 1.5622 14Ni6 16N6 14Ni6 15Ni6 -03.11 1501-509;510 - - ASTM A353 1.5662 X8Ni9 - X10Ni9 XBNi09 -03.11 - - - 2515 1.5680 12Ni19 Z18N5 - - -02.2 640A35 111A - 3135 1.5710 36NiCr6 35NC6 - - SNC23602.1/02.2 - - - 3415 1.5732 14NiCr10 14NC11 16NiCr11 15NiCr11 SNC415(H)02.1/02.2 655M13; 36A - 3415;3310 1.5752 14NiCr14 12NC15 - - SNC815(H)

655A1202.1/02.2 816M40 110 - 9840 1.6511 36CrNiMo4 40NCD3 38NiCrMo4(KB) 35NiCrMo4 -02.1/02.2 805M20 362 2506 8620 1.6523 21NiCrMo2 20NCD2 20NiCrMo2 20NiCrMo2 SNCM220(H)02.1/02.2 311-Type 7 - - 8740 1.6546 40NiCrMo22 - 40NiCrMo2(KB) 40NiCrMo2 SNCM24002.1/02.2 817M40 24 2541 4340 1.6582 35CrNiMo6 35NCD6 35NiCrMo6(KB) - -02.1/02.2 820A16 - - - 1.6587 17CrNiMo6 18NCD6 - 14NiCrMo13 -03.11 832M13 36C - - 1.6657 14NiCrMo134 - 15NiCrMo13 14NiCrMo131 -02.1/02.2 523M15 - - 5015 1.7015 15Cr3 12C3 - - SCr415(H)02.1/02.2 530A32 18B - 5132 1.7033 34Cr4 32C4 34Cr4(KB) 35Cr4 SCr430(H)02.1/02.2 530M40 18 - 5140 1.7035 41Cr4 42C4 41Cr4 42Cr4 SCr440(H)02.1/02.2 - - 2245 5140 1.7045 42Cr4 - - 42Cr4 SCr44002.1/02.2 (527M20) - 2511 5115 1.7131 16MnCr5 16MC5 16MnCr5 16MnCr5 -02.1/02.2 527A60 48 - 5155 1.7176 55Cr3 55C3 - - SUP9(A)02.1/02.2 1717CDS110 - 2225 4130 1.7218 25CrMo4 25CD4 25CrMo4(KB) 55Cr3 SCM420;SCM430

AM26CrMo402.1/02.2 708A37 19B 2234 4137;4135 1.7220 34CrMo4 35CD4 35CrMo4 34CrMo4 SCM432;SCCRM302.1/02.2 708M40 19A 2244 4140;4142 1.7223 41CrMo4 42CD4TS 41CrMo4 42CrMo4 SCM 44002.1/02.2 708M40 19A 2244 4140 1.7225 42CrMo4 42CD4 42CrMo4 42CrMo4 SCM440(H)02.1/02.2 - - 2216 - 1.7262 15CrMo5 12CD4 - 12CrMo4 SCM415(H)02.1/02.2 1501-620Gr27 - - ASTM A182 1.7335 13CrMo4 4 15CD3.5 14CrMo4 5 14CrMo45 -

F11;F12 15CD4.502.1/02.2 722M24 40B 2240 - 1.7361 32CrMo12 30CD12 32CrMo12 F.124.A -02.1/02.2 1501-622 - 2218 ASTM A182 1.7380 10CrMo9 10 12CD9, 10 12CrMo9, 10 TU.H -

Gr.31;45 - F.22 - - -02.1/02.2 1503-660-440 - - - 1.7715 14MoV6 3 - - 13MoCrV6 -02.1/02.2 735A50 47 2230 6150 1.8159 50CrV4 50CV4 50CrV4 51CrV4 SUP1002.1/02.2 905M39 41B 2940 - 1.8509 41CrAlMo7 40CAD6, 12 41CrAlMo7 41CrAlMo7 -02.1/02.2 897M39 40C - - 1.8523 39CrMoV13 9 - 36CrMoV12 - -

02.1/02.2 BL3 - - L3 1.2067 100Cr6 Y100C6 - 100Cr6 -03.11 BD3 - - D3 1.2080 X210Cr12 Z200C12 X210Cr13KU X210Cr12 SKD1

X250Cr12KU03.11 BH13 - 2242 H13 1.2344 X40CrMoV5 1 Z40CDV5 X35CrMoV05KU X40CrMoV5 SKD61

X40CrMoV511KU03.11 BA2 - 2260 A2 1.2363 X100CrMoV5 1 Z100CDV5 X100CrMoV51KU X100CrMoV5 SKD1202.1/02.2 - - 2140 - 1.2419 105WCr6 105WC13 10WCr6 105WCr5 SKS31

107WCr5KU SKS2, SKS3

MATERIAL CROSS REFERENCE LIST

Structural and constructional steel

Tool steel

�

184

*) Duplex stainless steel.

ISO CoromantMaterialClassifi-cation(CMC)

Country

Great Britain Sweden USA Germany France Italy Spain Japan

Standard

P

M

BS EN SS AISI/SAE W.-nr. DIN AFNOR UNI UNF JIS03.11 - - 2312 - 1.2436 X210CrW12 - X215CrW12 1KU X210CrW12 SKD203.11 BS1 - 2710 S1 1.2542 45WCrV7 - 45WCrV8KU 45WCrSi8 -03.11 BH21 - - H21 1.2581 X30WCrV9 3 Z30WCV9 X28W09KU X30WCrV9 SKD5

X30WCrV9 3KU X30WCrV9 3KU03.11 - - 2310 - 1.2601 X165CrMo - X165CrMoW12KU X160CrMoV12 -

V 1203.11 401S45 52 - HW3 1.4718 X45GrSi93 Z45CS9 X45GrSi8 F322 SUH102.1/02.2 - - - L6 1.2713 55NiCrMoV6 55NCDV7 - F.520.S SKT4

05.11/15.11 403S17 - 2301 403 1.4000 X7Cr13 Z6C13 X6Cr13 F.3110 SUS4031.4001 X7Cr14 - - F.8401 -

05.11/15.11 430S15 60 2320 430 1.4016 X8Cr17 Z8C17 X8Cr17 F3113 SUS43005.11/15.11 410S21 56A 2302 410 1.4006 X10Cr13 Z10C14 X12Cr13 F.3401 SUS41005.11/15.11 430S17 60 2320 430 - X8Cr17 Z8C17 X8Cr17 F.3113 SUS43005.11/15.11 420S45 56D 2304 - 1.4034 X46Cr13 Z40CM X40Cr14 F.3405 SUS420J2

Z38C13M05.11/15.11 405S17 - - 405 1.4002 - Z8CA12 X6CrAl13 - -05.11/15.11 420S37 - 2303 420 1.4021 - Z20C13 X20Cr13 - -05.11/15.11 431S29 57 2321 431 1.4057 X22CrNi17 Z15CNi6.02 X16CrNi16 F.3427 SUS43105.11/15.11 - - 2383 430F 1.4104 X12CrMoS17 Z10CF17 X10CrS17 F.3117 SUS430F05.11/15.11 434S17 - 2325 434 1.4113 X6CrMo17 Z8CD17.01 X8CrMo17 - SUS43405.11/15.11 425C11 - - - 1.4313 X5CrNi13 4 Z4CND13.4M - - SCS505.11/15.11 403S17 - - 405 1.4724 X10CrA113 Z10C13 X10CrA112 F.311 SUS40505.11/15.11 430S15 60 - 430 1.4742 X10CrA118 Z10CAS18 X8Cr17 F.3113 SUS43005.11/15.11 443S65 59 - HNV6 1.4747 X80CrNiSi20 Z80CSN20.02 X80CrSiNi20 F.320B SUH405.11/15.11 - - 2322 446 1.4762 X10CrA124 Z10CAS24 X16Cr26 - SUH44605.11/15.11 349S54 - - EV8 1.4871 X53CrMnNiN Z52CMN21.09 X53CrMnNiN - SUH35, SUH36

21 9 21 905.12/15.12 - - - 630 1.4542/1.4548 - Z7CNU17-04 - - -05.21/15.21 304S11 - 2352 304L 1.4306 - Z2CN18-10 X2CrNi18 11 - -05.21/15.21 304S31 58E 2332/2333 304 1.4350 X5CrNi189 Z6CN18.09 X5CrNi18 10 F.3551 SUS304

F.3541F.3504

05.21/15.21 303S21 58M 2346 303 1.4305 X12CrNiS18 8 Z10CNF 18.09 X10CrNiS 18.09 F.3508 SUS30305.21/15.21 304S15 58E 2332 304 1.4301 X5CrNi189 Z6CN18.09 X5CrNi18 10 F.3551 SUS304

304C12 2333 Z3CN19.10 - - SUS304L05.21/15.21 304S12 - 2352 304L 1.4306 X2CrNi18 9 Z2CrNi18 10 X2CrNi18 11 F.3503 SCS1905.21/15.21 - - 2331 301 1.4310 X12CrNi17 7 Z12CN17.07 X12CrNi17 07 F.3517 SUS30105.21/15.21 304S62 - 2371 304LN 1.4311 X2CrNiN Z2CN18.10 - - SUS304LN

18 1005.21/15.21 316S16 58J 2347 316 1.4401 X5CrNiMo Z6CND17.11 X5CrNiMo17 12 F.3543 SUS316

18 10

05.21/15.21 - - 2375 316LN 1.4429 X2CrNiMoN Z2CND17.13 - - SUS316LN18 13

05.21/15.21 316S13 2348 316L 1.4404 - Z2CND17-12 X2CrNiMo1712 - -05.21/15.21 316S13 - 2353 316L 1.4435 X2CrNiMo Z2CND17.12 X2CrNiMo17 12 - SCS16

18 12 - - - SUS316L05.21/15.21 316S33 - 2343/2347 316 1.4436 - Z6CND18-12-03 X8CrNiMo1713 - -05.21/15.21 317S12 - 2367 317L 1.4438 X2CrNiMo Z2CND19.15 X2CrNiMo18 16 - SUS317L

18 1605.51/15.51*) - - - S31500 1.4417 X2CrNiMoSi - - - -

19 505.51/15.51*) - - 2324 S32900 - X8CrNiMo - - - -

27 505.52/15.52*) - - 2327 S32304 - X2CrNiN Z2CN23-04AZ - - -

23 405.52/15.52*) - - 2328 - - - - - - -05.52/15.52*) - - 2377 S31803 - X2CrNiMoN Z2CND22-05-03 - - -

22 5305.21/15.21 321S12 58B 2337 321 1.4541 X10CrNiTi Z6CNT18.10 X6CrNiTi18 11 F.3553 SUS321

18 9 F.352305.21/15.21 347S17 58F 2338 347 1.4550 X10CrNiNb Z6CNNb18.10 X6CrNiNb18 11 F.3552 SUS347

18 9 F.352405.21/15.21 320S17 58J 2350 316Ti 1.4571 X10CrNiMoTi Z6NDT17.12 X6CrNiMoTi17 12 F.3535 -

18 10 17 1205.21/15.21 - - - 318 1.4583 X10CrNi Z6CNDNb X6CrNiMoNb - -

MoNb 18 12 17 13B 17 1305.21/15.21 309S24 - - 309 1.4828 X15CrNiSi Z15CNS20.12 - - SUH309

20 1205.21/15.21 310S24 - 2361 310S 1.4845 X12CrNi25 21 Z12CN25 20 X6CrNi25 20 F.331 SUH31005.22/15.22 316S111 - - 17-7PH 1.4568/1.4504 - Z8CNA17-07 X2CrNiMo1712 - -05.23/15.23 - - 2584 NO8028 1.4563 - Z1NCDU31-27-03 - - -05.23/15.23 - - 2378 S31254 - - Z1CNDU20-18-06AZ - - - �

Stainless and heat resistant materials

�

185

ISO Sweden USA Germany France Italy Spain Japan

Standard

-SM

K

BS EN SS AISI/SAE W.-nr. DIN AFNOR UNI UNF JIS20.11 - - - 330 1.4864 X12NiCrSi Z12NCS35.16 - - SUH330

36 16 -20.11 330C11 - - - 1.4865 G-X40NiCrSi - XG50NiCr - SCH15

38 18 39 1920.21 - - - 5390A 2.4603 - NC22FeD - -20.21 - - - 5666 2.4856 NiCr22Mo9Nb NC22FeDNB - -20.21 HR5,203-4 - - - 2.4630 NiCr20Ti NC20T - -20.22 - - - 5660 LW2.4662 NiFe35Cr14MoTi ZSNCDT42 - -20.22 3146-3 - - 5391 LW2 4670 S-NiCr13A16MoNb NC12AD - -20.22 HR8 - - 5383 LW2.4668 NiCr19Fe19NbMo NC19eNB - -20.22 3072-76 - - 4676 2.4375 NiCu30Al - - -20.22 Hr401,601 - - - 2.4631 NiCr20TiAk NC20TA - -20.22 - - - AMS 5399 2.4973 NiCr19Co11MoTi NC19KDT - -20.22 - - - AMS 5544 LW2.4668 NiCr19Fe19NbMo NC20K14 - -20.24 - - - AMS 5397 LW2 4674 NiCo15Cr10MoAlTi - - -20.32 - - - 5537C LW2.4964 CoCr20W15Ni KC20WN - -

- - - AMS 5772 - CoCr22W14Ni KC22WN - -23.22 TA14/17 - - AMS R54520 - TiAl5Sn2.5 T-A5E - -23.22 TA10-13/TA28 - - AMS R56400 - TiAl6V4 T-A6V - -23.22 TA11 - - AMS R56401 - TiAl6V4ELI - - -23.22 - - - - - TiAl4Mo4Sn4Si0.5 - - -

ASTMA48-76

08.1 01 0008.1 01 10 No 20 B GG 10 Ft 10 D08.1 Grade 150 01 15 No 25 B GG 15 Ft 15 D08.1 Grade 220 01 20 No 30 B GG 20 Ft 20 D08.2 Grade 260 01 25 No 35 B GG 25 Ft 25 D

No 40 B08.2 Grade 300 01 30 No 45 B GG 30 Ft 30 D08.2 Grade 350 01 35 No 50 B GG 35 Ft 35 D08.2 Grade 400 01 40 No 55 B GG 40 Ft 40 D

2789;1973 A536-72 NF A32-20109.1 SNG 420/12 07 17-02 60-40-18 GGG 40 FCS 400-1209.1 SNG 370/17 07 17-12 - GGG 40.3 FGS 370-1709.1 - 07 17-15 - GGG 35.3 -09.1 SNG 500/7 07 27-02 80-55-06 GGG 50 FGS 500-709.2 SNG 600/3 07 32-03 - GGG 60 FGS 600-309.2 SNG 700/2 07 37-01 100-70-03 GGG 70 FGS 700-2

ASTMA47-74A 220-76 2)

07.1 8 290/6 08 14 - MN 32-807.1 B 340/12 08 15 32510 GTS-35 MN 35-1007.2 P 440/7 08 52 40010 GTS-4507.2 P 510/4 08 54 50005 GTS-55 MP 50-5

P 570/3 08 58 70003 GTS-65 MP 60-3

30.21/30.22 LM25 4244 356.14247 A413.0 GD-AlSi12

LM24 4250 A380.1 GD-AlSi8Cu3LM20 4260 A413.1 G-AlSi12(Cu)LM6 4261 A413.2 G-AlSi12LM9 4253 A360.2 G-AlSi10Mg(Cu)

➤

Malleable cast iron

Aluminium alloys, cast

Nodular cast iron

Grey cast iron

CoromantMaterialClassifi-cation(CMC)

Country

Great Britain

186

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NOTES

187

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