Ingot Cleanliness Improvements Using SprueExtensions Beyond The Mold Outlet

Ryan VanderMeulen

ArcelorMittal Coatesville

April 11, 2012

2

Steelton

Coatesville

Conshohocken

Burns Harbor Cleveland

Lackawanna

Hennepin

Columbus Coatings

Riverdale

Indiana Harbor

Steelmaking and processing facilities

Processing facilities

Research center

Research Center

Weirton

Georgetown

ArcelorMittal USA Locations

Newton

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ArcelorMittal USAPlate Production Locations

Steelmaking, Rolling, Heat Treating:Burns Harbor, Coatesville

Rolling & Heat Treating:Conshohocken, Gary

Steelmaking:Indiana Harbor,Cleveland, Riverdale

CoatesvilleConshohocken

BurnsHarbor,Gary

ClevelandIndiana Harbor

Riverdale

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Plate Mills Production Focus

• Burns Harbor– 160” – larger, TMCP, Q&T, precise weight

– 110” – commodity to 1”

– 160” @ Gary – commodity to 1.5”, Q&T

• Conshohocken– 110” - commodity, thin, Q&T

• Coatesville –– 140” - heavy, varied chemistries, Q&T

– 206” - very wide and heavy, Q&T

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Production Focus

• EastClad, Flamecut, ConversionMost alloy and Q&TVery clean steelVery wide or heavy plateLight thickness plateSmall special orders

• WestControl rolledPrecise weightSpecial surface requirementsVery large ordersHeat Treated Commodity

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ArcelorMittal USA OperationsCoatesville Steelmaking Process Plan

Ladle

Argon Stirring

Electrodes

Wire Feed

Argon Stirring

AutomaticAlloys

Ladle Furnace

Electric Arc Furnace

ContinuousCast Slabs

Ladle Degasser

BottomPoured Ingots

AutomaticAlloys

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Ingot CastingCoatesville

• Bottom pouring

• Hot topping

• Argon shrouding

• Maximum sizeplate 50 tons (45 Mt)

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Bottom Poured, Ingot Casting

Ladle

ArgonShroud

Argon Inlet

CenterRunner

RunnerBrick

MoltenSteel

Mold

CastingPowder

Hot Top

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Products Produced From Ingots

• Thick plates, 3/1 reduction for PVQ; structural grades2/1; military 4/1

• Heavy plates over ~13.5 sTon

• Difficult chemistries– High sulfur free machining grades

– Tool steels

– Certain military grades

– Some unique customer requirements (prequalification)

• Grades covering wide thickness range with limitedproduction

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High Strength Q&T Steels

• A514 family and T-1®

Steels, Hardwear®

• High strength orabrasion resistance

• Flatness requirements

1/2 commercial

• Fabrication guidelines

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A514 Steels

• A514A - to 1-1/4” N-A-Xtra,National

• A514B * T-1A® to 1-1/4”

• A514E - to 6” ex-Armco

• A514F* T-1® to 2-1/2”

• A514H* T-1B® to 2”

• A514Q* T-1C® to 6” basis for gearrack grades

* PWHT cracking concerns

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API Offshore Steels

• 2H42 and 50 (N)

• 2Y50 and 50T (QT)

• 2MT1 (CR, AC)

• 2Y60 (QT)

• Burns Harbor

– AC, N, QT

• Coatesville

– N, QT

– Special Chemistry (Pcm)

– Heavy plate, ingot

– RP 2Z prequalified Ingot to 3”

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Pressure Vessel Steels

• Shipped to ASTM A20requirements

• Fabricators export theirvessels

• Plate export opportunities

• Most popular grades A516,A387 - 11/22, A353/553, Clad,A203E, A537, A299

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A516

• C-Mn steels to 15” (380 mm) thick and 100,000pounds (45,000 kg) weight

• -50oC to +300oC temperature pressure vesselapplications, Grades 55, 60, 65 and 70

• Carbon equivalent controls and HIC - testing

• Available normalized or Q&T

• Similar behavior of A299 steels

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A387

• Cr-Mo steels to 12” (305 mm) thick and 100,000pounds (45,000 kg) weight

• Grades 11 (1-1/4 Cr - 1/2 Mo) and 22 (2-1/4 Cr - 1Mo) most popular; other grades to 9% Cr

• Elevated temperature pressure vessel applications

• Temper embrittlement resistance

• Post weld heat treatment (stress relief)

• Available N&T or Q&T

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Roll-Bonded Clad

• Composite of economical “Backing Steel” and high performancealloy

– examples: A516/304L, A387/410S, A36/C276

• Assembly of a “Clad Pack”

• Cost advantages

• Fabrication procedures - forming and welding

• Pressure vessels, FGD systems, pulp and paper equipmentSpacer bars

Nickel LayerBacking Steel

Alloy Inserts Parting Compound

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Military Armor

• Navy Armor Steels - HY-80 & 100,HSLA-80 & 100 - surface shipsand submarines

• Army Armor Steels - moderateand high hardness grades - M-1tanks, other vehicles

• Require Q&T and Fineline®

• Special testing - first article,ballistic

• Plates from ingots usedparticularly in Carriers

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AISI Alloy and Mold Steels

• Chemistry only grades

• Most popular 4140, 4142, 4130,

8620, 4340

• All vacuum degassed, some may

be Clean-Cut or Fineline

• Thermal cutting and quench

cracking concerns

• Used in variety of tooling

applications, including MTD steels

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MTD® Steels

• Mold, tool and die pre-hardened steels for plasticinjection molds and holder blocks, 262-321HB*

• MTD #1 - N&T 4142 used to 6-1/2” thick

• MTD #2 - Q&T 4130 used to 12” thick

• MTD #3 - Q&T .30% carbon, Fineline quality to12” thick; ingot only for internal quality, BEUwhere possible

• MTD #4 - N&T 4150 used to 6-1/2” thick

• MTD #1, #2, #4 may be Clean-Cut quality

* MTD #1 and #4, to 3”: 241-320 over 3 - 6-1/2”

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Free Machining Grades

• Higher sulfur levels for improved machinability

• Clean-Cut® 20 and 45, .06/.12 sulfur, twocarbon levels, calcium treated to 15” thick

• C1119 mod. and C1144 mod., .24/.33 and.20/.33 sulfur levels always ingot

• Clean-Cut® Alloy Steels, .02/.04 sulfur, calciumtreatment available in 4140, 4142, 4150, 8620,MTD #1, #2 and #4

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Tool Steels

• Cold work tool steels - A2, 01, S7, S5, D2, A8 mod.

• Mostly ingot produced at Coatesville, some meltedoff-site– D2 ingot from outside source

– S5 can be strand cast

• Long processing cycles

• Produce full sized plates that customers can cut intobars

• Flatness tolerances are critical for cutting andmachining

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Bridge Steels

• Industry push to use ASTMA709

• Grades 36 through 100 ksiyield

• Three zones for determiningCVN impact requirements,also fracture-critical membercriteria

• New HPS 50W/70W/100W

• Ingots used in thick, wide&/or long plates

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Flame-Cut Products

• Oxygen-fuel or plasma cuttingof all grades, thicknesses andweights of plate we can roll

• Beveling of edge detail/weldpreparation to drawingspecifications

• Plates/parts can be pressflattened to meet tolerances

• Finished pieces used instructural and sub-assembly,forming, fabrication andmachining applications

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Common Ingot Quality Issues

• Cracks

– Rate of Rise

– Mold Centering

• Hot Top Fins

– Board Fit in Molds

• End/Side Laminations

– Solidification

– Rolling

• Pipe/Burst/UT Failure

– Solidification

– Cooling

– Trapped Junk

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Potential Sources of Trapped Junk

• Foreign debris including cardboard

• Damaged Refractory Brick

• Nalcosil

• Runner Sand

• Fluxes/Powders – most common HT2

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Ladle Sand

• Prevents steel from escaping through the outlet

• Protects opening of ladle from damage

• Allows for better flow of steel

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Refractory Brick

• Can be easily fractured or crack

• Uneven plates cause bricks to be misaligned

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The‘Trap’

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The ‘Trap’

Sprue Cap

14” Double MaleStraights

9” Slotted Outlet

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Picture of Sprue

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End of Sprue

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Diagram of Sprue

Note: A, B, C, D, E are all ½”

13”

OUTLET

.5”0 2”1” 2.5” 6.5” 7” 13.5”

END A B C D E

Distance from the End to Outlet

1” 4” 6”

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End Pieces

• Where most junk was found

• Not fully circular

C0082 C0086Melt No.-Position C0192-1 C0192-3

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Definition of Junk

• All non-metallics

• Material on edge of piece extending deep into the surface

• For air bubbles, only parts that appeared to have been non-steel material

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0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

3.5%

4.0%

0 2 4 6 8 10 12 14

Distance from End to Outlet (inches)

Per

cen

tIn

clu

sio

n

C0082

C0086

Trapped Inclusions for C0082/C0086

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0%

2%

4%

6%

8%

10%

12%

14%

16%

18%

0 2 4 6 8 10 12 14

Distance from End to Outlet (inches)

Per

cen

tIn

clu

sio

n

C0192-1

C0192-3

Trapped Inclusions for C0192

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Percent Inclusion by Piece

Piece C0082 C0086 C0192-1 C0192-3

A 3.8% 3.6% 13.3% 15.8%

B 1.2% 0.59% 9.8% 6.5%

C 0.17% 0.08% 3.9% 6.0%

D 0.17% 0% 2.8% 7.6%

E 0.12% 0% 0%

Total % Inclusion 0.42% 0.25% 3.3% 5.5%

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Indication of Swirling Motion

C0086A

C0086B

C0192-1D

C0192-3D

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0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Middle % 6.7% 2.2% 27.3% 25.1%

Outer % 93.3% 97.8% 72.7% 74.9%

C0082 C0086 C0192-1 C0192-3

Location of JunkOutside

Middle

1.5”

1.06”50% ofArea

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Flow Model

CenterRunner

Mold

Sprue

‘Trap’

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Flow Video

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Cost

• Refractory cost increase per ingot of ~3%.

• Worst-case yield loss of ~0.1%.

• Total cost increase under $1.00/ton.

• One trapped junk rejection = $5,000+ depending on size andgrade. Can be over $20,000 for large armor ingots.

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Follow-Up Work

• Work with vendor to develop a standard “trap brick”

• Integrate trap usage into all special heats to start

• Make traps standard for all heats

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Conclusion

• Demonstrated ‘Trap’ is capable of catching junk

• Minimal cost and yield loss

• Potential to produce cleaner ingots and reduce the number ofrejections

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Questions?