Internship at GTTC, Mysore

Industrial Training at “GOVERNMENT TOOL ROOM AND TRAINING CENTRE”

Department of Mechanical Engineering, SJCE, Mysore Page 1

CHAPTER 1

1.1 INTRODUCTION:

In-Plant Training will provide an industrial exposure to the students as well as to

develop their career in the high tech industrial requirements. Reputed

companies are providing in-plant training to Students. Here students are initially to

get counseled in order to emerge out their interest in various streams and what are all

the basic concepts they know about that domain.

In-plant Training refers to a program which aims to provide supervised

practical training with spiced timeframe. This training can be carried out either in

government organizations or in private sector.

In-plant training is a programme for post graduates that gives them an

opportunity to expose themselves in the real career world so as to they will learn

how to relate theoretical learning before and real practical in work

environment.

Besides that, in future, they wi l l be having good preparation and

understanding for their field of profession. After the successful completion of

studies students has to face this competitive world with this knowledge to face

many problems and to find the right solutions which is to be solved in the

minimum duration of time. The implant training is getting totally different from the

class environments.



1.2 Objectives of In-Plant Training:

To get an Industrial exposure.

To be aware of the happening in a particular industry.

To achieve knowledge about different sectors in the market for making a Choice

as to which go for.

To learn functioning and operations of different departments in an organization.

To get knowledge about the working culture of the organization.

To have knowledge about the huge management practices and get the practical

knowledge of what we have studied

1.3 METHODOLOGY OF COLLECTING DATA:

There are many methods to collect required information during in-plant training

like:

Observation of the entire process..

Discussion about the observed process with the staff involved.

Interview with the experienced employees involved.

Referring relevant documents related to the process.



Chapter 2

PROFILE OF THE COMPANY

“It`s precision that makes the world go round”

A premier Tool Room and Training Centre established in 1992 at Mysore, Karnataka,

India with assistance of the Government of Denmark, has extensive facilities in Tool

making and training. Government tool and Training Centre (GTTC) is a modern tool

room and training centre with state-of-art CAD/CAM equipment, machinery and

inspection facilities to meet the complex needs of discerning customers.

GTTC is committed to achieve customer satisfaction in quality and delivery of

tool engineering education, services and precision machining.

GTTC has acquired mastery in Tool Engineering and vast experience in

conducting well structured, practical oriented training programmes leading to post

graduation, diplomas and certificates.

Realizing the need to update and upgrade the skills of existing technical

personnel in industry, GTTC conducts a number of short term programmes in tool

design, advanced manufacturing techniques, design analysis and CNC programming

for manufacture and other aspect of manufacturing.

The state-of-art sophisticated manufacturing facility consists of 3 to 5 axis high-

speed CNC machining centres, CNC jig grinding, CNC wire EDM, CNC co-ordinate

measuring machine and other supporting machineries and facilities.

The computer integrated manufacturing facility in DNC network and supported by

high end software`s such as I-DEAS, for design and manufacture, Uni-Graphics,

Pro-E, Master-cam, Mechanical Desktop and Analysis package like C-Mold, Mold

Flow and Pro-Cast.



2.1 LAYOUT OF GOVERNMENT TOOL ROOM and TRAINING CENTER

E- ENTRANCE

S- SECURITY ROOM

1. HSM M/C

2. MAINTENANCE

3. ASSEMBLY

4. BENCH WORKS

5. DNC

6. QUALITY ANALYSIS

7. CMM



8. CNC MILLING

9. CNC MILLING

10. MARKETING DEPARTMENT

11. PLANNING DEPARTMENT

12. SURFACE GRINDING

13. CNC TURNING

14. JIG GRINDING

15. WIRE EDM

16. EDM

17. TRAINING AND ACCOUNTS SECTION

18. CANTEEN

19. CAD CCENTRE

20. LASER M/C

2.2 MANAGEMENT DEPARTMENT:

The management of affairs of the Tool Room, which has been set up as

Government of India Society, rests with the Governing Council constituted by

Government of India. DC(SSI) is the President of this Society and Chairman of their

Governing Council. Adequate representation to State Government, donor country and

Industry Associations has been provided in the constitution of Governing Council.

2.3 MARKETING DEPARTMENT:

Marking reaches right customers and explains him about special machines and

quality of work carrying out in the industry through advertisement and by other means.



Thus it brings work orders for company and takes care for dispatching the same

in scheduled time. It consists of marketing departments HOD and marketing officials

work under him.

Responsibilities and authorities

Receiving the customers and soliciting their enquiries.

Interacting with customers and preset the introduction broachers, hear doubts

and machines test etc, whenever required, arranging the shop visit if necessary.

Preparation of estimations/worksheets, consulting tool planning and tool

production for schedule and cost details if required.

Responsible for preparation of quotation and sending same to the customer.

Coordinating with administration department for advertisement.

Responsible for releasing work order instructions to planning and follow-up for

the status of order.

In the event of any delay in meeting the delivery schedule the informing customer

accordingly.



To dispatch the completed work order to customer with proper documents.

Authorizing to sign delivery note.

Table 2.1 Work Order Instruction

From: Marketing To: Planning

Order conformation number ******

Customer ISRO

Description Stud

Scope of work Mikron

Quality 102 Nos

Drawing and specification Provided by the customer.

Raw material/ specification Stainless Steel

Date of delivery 10/09/13

Priority Normal

Acceptance criteria Visual acceptance

Any other information ------

2.4 PLANNING DEPARTMENT:

Before starting the actual production process planning is done. It gives the idea of

sequence of operations, selection of machine, cost and time required, at the same time

process will be performed with high percentage of material utilization. Planning is a

primary function of human and material resources in an enterprise to realize maximum

profits.



Process planning represents the link between Engineering design and shop floor

manufacturing. Since process planning determines how a part will be manufactured, it is

the major determinant of manufacturing costs and profitability.

PLANNING CONSISTS OF FOLLOWING WORKS:

1. Tool and high tech components: It involves job planning with effective utilization

of machines available and using right tool for right operation

2. Preparing process sheet: process sheet in forms the operations and machining

conditions such as diameter of components, feed, speed, material setting etc.

3. Job follows up: to follow up the progress of the job in the shop floor.

4. Pre tooling: Pre machining of the job in conventional machines to save the time

of high tech machines.

5. Route card: Route card is prepared to mention in sequence.



Table 2.2 Job Card Format

GTTC MYSORE JOB CARD UNIT CODE:

OC number Description: Dept:

Part No: Qty:

Planned date of loading Completion date:

Recommended Estimated time: Actual time:

Machine Section

Operation

Special instruction

Foreman/ shift in charge

Remark

Date: Signature:

Job card prepared by: Section:

Name: Date:



Table 2.3 Process Sheet Layout

GTTC Process sheet Sheet no:

Customer Date:

Part drawing no: Material specification:

Part description code: Raw material size:

Qty: OC no: Drawing SN/no:

Operation

No

Process details/

Drawings

Machine Tool and gauges

*** **** **** ****

Process

Prepared

By:

Process

Approved

By:

Co-

ordinate

By:

Process sheet prepared by:



Table 2.4 Operation Drawing Sheet

GTTC

MYSORE

Operation Drawing

OC No: Part No: Reference Drawing No:

Machine: Section: Date: Qty:

DRAWING..........................................................................................

Drawing No: Checked by:



2.5 DESIGN and PROGARMMING DEPARTMENT:

It is the maim organ of the industry. Quality of work done, hence the name and fame

of the company depends largely on this section. Its function can be enlisted as below.

Collection of required technical data, study of component drawing etc.

Design calculations are done and suitable assumptions are made.

Design layout considering cost effectiveness, machine available. It also includes

comparing new design with similar.

Design review, design verification and changes if any will be implemented.

Assessment of material selection.

Preparation of drawing and bill of materials.

Generation of CNC part programs considering optimum cutting tools and

parameter.

GTTC Design is well equipped with the computers. The designers were engaged

in designing the ISRO projects.

The design department is well equipped with the software like.

1. AUTOCAD

2. MASTER CAM

3. SOLID WORKS



Chapter 3

Machines and its Specifications

3.1 CNC MACHINE:

The term “CNC” is a generic term which can be used to describe many types of

device, this would include plotters, vinyl cutters, 3D printers, milling machines and

others. CNC stands for Computer Numerically Controlled and basically means that the

physical movements of the machine are controlled by instructions, such as co-ordinate

positions that are generated using a computer.

A machine tool that uses programs to automatically execute a series of

machining operations. CNC machines offer increased productivity and flexibility.

All CNC machine types share this commonality: They all have two or more

programmable directions of motion called axes. An axis of motion can be linear (along a

straight line) or rotary (along a circular path). One of the first specifications that implies a

CNC machine's complexity is how many axes it has. Generally speaking, the more

axes, the more complex the machine.

The axes of any CNC machine are required for the purpose of causing the

motions needed for the manufacturing process. In the drilling example, these (3) axis

would position the tool over the hole to be machined (in two axes) and machine the hole

(with the third axis). Axes are named with letters. Common linear axis names are X, Y,

and Z. Common rotary axis names are A, B, and C.

GTTC Mysore is well equipped with the CNC milling machines. Most of the

machines are HIDENHAIN and FANUC control. For jobs the job setting as well as

programming is done by the operator itself. For every job, designer of design

department does the modeling and generates the tool paths.



Table 3.1 Specification of CNC Milling Machine

MAKE MIKRON MIKRON MIKRON MIKRON MIKRON

MODEL WF31DE WF32C VHC750 HSM520 UMC600

ORIGIN SWIZZ SWIZZ SWIZZ SWIZZ SWIZZ

NO.OF M/C 02 01 01 01 01

Control TNC407 TNC425 TNC415 RMS3 TNC426

Table size

(mm)

530x900 600x1000 Ф630 600x500 Ф630

Traverse

(mm)-X

560 600 750 520 600

Traverse

(mm)-Y

500 600 600 430 600

Traverse

(mm)-Z

400 450 550 220 500

Spindle

speed(RPM)

40-4000 10-6300 20-6300 50000 20-6300

NC rotary

table Ф/PW

500±6” 600±6” 600±6” -- 600±6”

Automatic

tool changer

-- 22 34 06 44

Max. Wt of

job (kgs)

350 400 500 200 500

Tilting table

range from

m/c

Five axis Machining centre USM 600 200



3.2 Electric discharge machining (EDM):

Introduction about EDM process:

Electrical Discharge Machining (EDM) is a controlled metal-removal process that

is used to remove metal by means of electric spark erosion. In this process an electric

spark is used as the cutting tool to cut (erode) the workpiece to produce the finished

part to the desired shape. The metal-removal process is performed by applying a

pulsating (ON/OFF) electrical charge of high-frequency current through the electrode to

the workpiece. This removes (erodes) very tiny pieces of metal from the workpiece at a

controlled rate.

h = height of crater, mm, D = diameter of crater

Figure 3.1 Principle of EDM



Table 3.2 Specifications of Electro discharge machines

MAKE ELECTRONICA MAKINO EDNC MAKINO EDNC

ORIGIN INDIA JAPAN JAPAN

CONTROL ------------------ CNC MGE 60 CNC MGE 20

TABLE

SIZE(mm)

550×350 550×750 350×550

TANK

SIZE(mm)

325×490×820 400×700×1000 300×430×680

TRAVERSE(m

m)- X mm

300 600 300

TRAVERSE(m

m)- Y mm

200 400 250

TRAVERSE(m

m)- Z mm

250 250 250

MAX. JOB

WEIGHT(kg)

300 1500 500



3.3 Wire electrical discharge machining (WEDM)

Principles of EDM Electrical Discharge Machining (EDM) is a controlled

metal-removal process that is used to remove metal by means of electric spark erosion.

In this process an electric spark is used as the cutting tool to cut (erode) the workpiece

to produce the finished part to the desired shape. The metalremoval process is

performed by applying a pulsating (ON/OFF) electrical charge of high-frequency current

through the electrode to the workpiece. This removes (erodes) very tiny pieces of metal

from the workpiece at a controlled rate.

Major Components

A Wire EDM system is comprised of four major components.

(1) Computerized Numerical Control (CNC)

Think of this as “The Brains.”

(2) Power Supply

Provides energy to the spark.

Think of this as “The Muscle.”

(3) Mechanical Section

Worktable, work stand, taper unit, and wire drive mechanism.

Think of this as “The Body.”

(4) Dielectric System

The water reservoir where filtration, condition of the water and temperature of the

water is provided and maintained.

Think of this as “The Nourishment.”



Table 3.3 Specifications of Wire electrical discharge machining (WEDM)

Make ELECTRONICA MAKINO

Origin INDIA JAPAN

Table

Size(mm)

150×400×500 770×570×210

Traverse-

X (mm)

300 600

Traverse-

Y (mm)

400 440

Traverse-

Z (mm)

150 220

Traverse-

UAxis

(mm)

±15 28

Traverse-

V Axis

(mm)

±15 28



3.4 Grinding:

3.4.1 Introduction about grinding process:

Grinding is a metal cutting operation performed by means of abrasive particles

rigidly mounted on a rotating wheel. Each of the abrasive particles act as a single point

cutting tool and grinding wheel acts as a multipoint cutting tool. The grinding operation

is used to finish the work pieces with extremely high quality of surface finish and

accuracy of shape and dimension. Grinding is one of the widely accepted finishing

operations because it removes material in very small size of chips 0.25 to 0.50 mm. It

provides accuracy of the order of 0.000025 mm. Grinding of very hard material is also

possible.

Figure 3.2 cutting action of abrasive grains in Grinding Machine



3.4.2 Grinding wheels

Grinding wheel consists of hard abrasive grains called grits, which perform the

cutting or material removal. A grinding wheel commonly identified by the type of the

abrasive material used. The conventional wheels include aluminum oxide and silicon

carbide wheels while diamond and CBN (cubic boron nitride) wheels fall in the category

of super abrasive wheel.

3.4.3 Grinding wheel abrasives:

An abrasive is a hard and tough substance. It has many sharp edges.

Abrasives of following types

1. Natural

Sandstone

Emery

Diamond

Garnet

2. Synthetic

Aluminum oxide

Silicon carbide

Cubic boron nitride

Boron carbide



Table 3.4 Surface grinding machine

MAKE JAKOBSEN JAKOBSEN JAKOBSEN

MODEL 618 1026 1832

ORIGIN DENMARK DENMARK DENMARK

NO.OF

MACHINE

06 04 01

TABLE SIZE 450×250 650×250 800×450

TRAVERSE

X AXIS( mm)

450 650 900

TRAVERSE

Y AXIS( mm)

200 300 500

TRAVERSE

Z AXIS( mm)

400 400 650

MAGNETIC

BED

250×450 250×600 450×800



3.5 Cylindrical grinding

The cylindrical grinder is a type of grinding machine used to shape the outside of

an object. The cylindrical grinder can work on a variety of shapes; however the object

must have a central axis of rotation. This includes but is not limited to such shapes as a

cylinder, an ellipse, a cam, or a crankshaft.

Plate 3.1 Cylindrical Grinding Machine

http://en.wikipedia.org/wiki/Grinding_machine

http://en.wikipedia.org/wiki/Cylinder_%28geometry%29

http://en.wikipedia.org/wiki/Ellipse

http://en.wikipedia.org/wiki/Cam

http://en.wikipedia.org/wiki/Crankshaft



Table 3.5 Specification of Cylindrical Grinding Machine

MAKE STUDER

MODEL FAVOURIT-S 30

ORIGIN SWITZERLAND

NO.OF MACHINES 01

SWING OVER BED, mm 350

CHUCKING DIA

INTERNAL mm

125

CENTRE DISTANCE, mm 650

TABLE SWIVEL, Degree 10 ◦

WHELL HEAD SLIDE,

mm

300

3.6 Jig Grinding

Introduction about jig grinding process:

A jig grinder is a machine tool used for grinding complex shapes and holes

where the highest degrees of accuracy and finish are required.

It may be used to grind items such as jigs, dies, and gauges. A jig grinder

typically uses a removable, air-driven spindle. This is used to rotate the grinding wheels.

The air spindles are interchangeable to achieve varying surface speeds.

http://en.wikipedia.org/wiki/Machine_tool



Grinding machines generally work on a similar principle to jig grinding. But one of

the limitations of the various grinding machines is their lack of precision. Hence for

precision grinding Jig grinding machines are used. Many Jig machines are now

computerized and operate with special software.

This often eliminates much of the geometric calculating once required of the

operator. Much of the labor has also been reduced by the automation of these

machines. The improvements made can result in much faster grinding, operation by

less-skilled workers, and a higher degree of accuracy.

Plate 3.2 Jig Grinding Machine

Jig grinding machine in GTTC:

MOORE Jig grinding machine

Model CPS 450

ORIGIN USA



Table3.6 MOORE Jig grinding machine Specification

Maximum bed

travels

X axis 460mm

Y axis 280mm

U axis 1.5mm (depth of cut)

C axis rotary 360˚

Capacity of

outside diameter

196mm

Spindle RPM

Minimum 4000

Middle 60,000

Maximum 1, 20,000

Maximum weight

of job

150 kg

Least count of

machine

0.0001mm

Accuracy of M/c 2 to 3microns



3.7 LASER WELDING

Laserwelding is a non-contact process that requires access to the weld zone

from one side of the parts being welded. The weld is formed as the intense laser light

rapidly heats the material-typically calculated in milli-seconds. The flexibility of the laser

offers three types of welds; conduction mode, conduction/penetration mode and

penetration or keyhole mode.

One of the largest advantages that pulsed laser welding offers is the minimal

amount of heat that is added during processing. The repeated "pulsing" of the beam

allows for cooling between each "spot" weld, resulting in a very small "heat affected

zone". This makes laser welding ideal for thin sections or products that require welding

near electronics or glass-to-metal seals. Low heat input, combined with an optical (not

electrical) process, also means greater flexibility in tooling design and materials.

Figure 3.3 Laser Welding Process



Welding requires high energy density that can be achieved by working at the

focal point of the optical system. The absorption coefficient of the laser beam by the

material depends of material nature and Wavelength of the laser source

At sufficiently high specific powers, a key hole filled with metal vapour is formed

in the material. The wall of the keyhole consists of molten liquid metal. The molten pool,

which is created and maintained in this way, is moved between the parts to be

assembled and the metal resolidifies behind the laser beam.

This phenomenon, which occurs in the case of a continuous beam (laser) is

significantly different in the case of a pulsed beam (pulsed YAG laser). Indeed, the bead

is then created by a series of partially overlapping spots. The welding process is then

similar to that already described as a result of the reached peak energy levels, the

material is melted or, even, vaporized instantaneously. This is followed condensation

and immediate solidification.

3.7.1 Preparations of Joints

The preparation of joints is very important having many implications regarding

the design of the weld.

The workpieces are correctly positioned together

The workpieces are not beveled.

3.7.2 Main Materials Worked With Laser Yag Machine

Ferrous metals,

Non-Ferrous Metals

Plastics

Ceramics

Leather



Plate 3.3 Nd YAG Continues Wave Laser:

Table 3.7 Specification of Nd YAG Continues Wave Laser

Capacity 400W CW-Nd

Size 500×300

Precision 0.02mm on 50mm

Operation Cutting and welding

Control software FLOCON

Assisting gas O2,N2,A2

Machinability CUTTING: Steel up to 2mm, Stainless

steel up to 1 mm, suitable for thin foil

cutting

WELDING: Stainless steel and Steel up to

1mm



3.8 LASER CUTTING

Laser cutting is one of the most common industrial applications of the laser. In

many cases, the laser happens to be able to cut faster and with a higher quality than the

competing processes ( punching/nibbling, plasma, abrasive fluid jet, wire EDM…)

Plate 3.4 Laser Cutting Process

The principle of laser cutting

Laser cutting is a thermal separation process. Our pulsed Nd: YAG and fiber

lasers permit a controlled heat entry which is optimum for fine cutting. The high peak

performance of our laser permits a maximum cut depth of up to 10mm.

As the laser beam can be focused on a very small diameter for high precision,

fine cuts are possible with a minimum cut width of up to 15 µm (0.0006 in). In addition,

the heat-affected zone along the cut is very small (up to 2µm). This means that

deformations of the parts to be processed can be avoided.

The high energy depth in the focus point of the laser beam causes the material to

melt and evaporate. By using an active or neutral process gas, for example, oxygen,

nitrogen, or argon, the melted material is blown out. If the work piece or laser beam is

now moved, a cut is created.



The smallest possible cut width is dependent on both the beam characteristics

and the material and material strength. When cutting fine contours, the precision and

dynamics of the cutting machine are of extreme importance.

Table 3.8 Specification of Laser Cutting Machine

Power 2000W CO2

X/Y/Z table 1250×1250×400mm

Precision 0.05mm on 50mm

Application Cut any profile on metals:MS:14mm thick,

stainless steel-5mm thick,Al-4mm thick,

Cu-1.5 mm thick, wood upto-25mm thick



Chapter 4

QUALITY CONTROL

4.1 INSPECTION

Inspection is the most common method of attaining standardization, uniformity

and quality of workmanship. It is the cost art of controlling the product quality after

comparison with the established standards and specifications. It is the function of quality

control. If the said item does not fall within the zone of acceptability it will be rejected

and corrective measure will be applied to see that the items in future conform to

specified standards.

Inspection is an indispensable tool of modern manufacturing process. It helps to

control quality, reduces manufacturing costs, eliminate scrap losses and assignable

causes of defective work

4.2 PURPOSE OF INSPECTION

1. By thorough inspection, we can detect faults at every manufacturing process and

rectify them.

2. It helps in building up the reputation of a firm or concern.

3. It improves the quality of the product.

4. It reduces cost spent on scrap pieces and further process can be stopped if

mistake is going on.



4.3 Types of Inspection

Floor Inspection:

It suggests the checking of materials in process at the machine or in the

production time by patrolling inspectors. These inspectors move from machine to

machine and from one to the other work centres. Inspectors have to be highly skilled.

This method of inspection minimize the material handling, does not disrupt the line

layout of machinery and quickly locate the defect and readily offers field and correction.

Centralized Inspection:

Materials in process may be inspected and checked at centralized inspection

centre which are located at one or more places in the manufacturing industry.

Combined Inspection:

Combination of two methods whatever may be the method of inspection, whether floor

or central. The main objective is to locate and prevent defect which may not repeat itself

in subsequent operation to see whether any corrective measure is required and finally

to maintained quality economically.

4.4 INSTRUMENTS AT INSPECTION DEPARTMENT

1. Profile projector

2. Tool makers microscope

3. Height master

4. Co-ordinate measuring machine



1. PROFILE PROJECTOR

The main principle of operation is a specimen is placed on the glass stage. The

stage is then illuminated from below and the resulting image is picked up by the

microscope objectives and projected to a large built-in projection screen. Since the

specimen has underlighting, the fine microscopic details are eliminated and only the

details of contour and profile are seen. A drawing can be affixed to the profile projector‟s

large viewing screen and the contour can be easily traced or compared to other profiles

and contours on the other drawings.

Plate 4.1 Profile Projector



Table 4.1 Specifications of Profile Projector

INSTRUMENT PROFILE PROJECTOR

ORIGIN JAPAN

Effective diameter, mm 250

Angular resolution, range, degree 1.±360º

Cross travel range, mm 50×50

Work stage dimension, mm 152×152

Micrometer head, mm 0.001×25

Max. work piece height, mm 75

Special accessories 20X,50X,10X

Accuracy 0.001

2. TOOL MAKER’S MICROSCOPE

A tool maker microscope is a type of a multi functional device that is primarily

used for measuring tools and apparatus. These microscopes are widely used and

commonly seen inside machine and tools manufacturing industries and factories. These

microscopes are also inside electronics production houses and in aeronautic parts

factories. A tool maker microscope is an indispensable tool in the different

measurement tasks performed throughout the engineering industry.

The main use of a tool maker microscope is to measure the shape, size, angle,

and the position of the small components that falls under the microscope‟s measuring

range.

A tool maker microscope is primarily used for measuring the shape of different

components like the template, formed cutter, milling cutter, punching die, and cam. The

pitch, external, and internal diameters are specifically measured as well.



The thread gauge, guide worm, and guide screw are conveniently handled as

well. As far angles are concerned, the thread and pitch angle are of chief concern.

Plate 4.2 Tool Maker‟s Microscope

Table 4.2 Specification of Tool Maker‟s Microscope

INSTRUMENT TOOL MAKER‟S MICROSCOPE

ORIGIN JAPAN

Magnification 10X,15X,20X

Stage size 152×152

Travelling distance, mm 50×50

Max.work piece height, mm 115

Accuracy 0.005



3. HEIGHT MASTER

It is a high precision instrument to measure and transfer of height on the job. It

can be used as a master for calibration in Standards

Room and in Tool Room

Plate 4.3 Height Master

Table 4.3 Specification of Height Master

INSTRUMENT HEIGHT MASTER

ORIGIN JAPAN

Max.height,mm 300

Accuracy, mm 0.001

Read out DIGITAL

Stroke,mm 20



4. CO-ORDINATE MEASURING MACHINE

A coordinate measuring machine (CMM) is a device for measuring the physical

geometrical characteristics of an object. This machine may be manually controlled by an

operator or it may be computer controlled. Measurements are defined by a probe

attached to the third moving axis of this machine. Probes may be mechanical, optical,

laser, or white light, amongst others.

The typical "bridge" CMM is composed of three axes, an X, Y and Z. These axes

are orthogonal to each other in a typical three dimensional coordinate system. Each

axis has a scale system that indicates the location of that axis. The machine will read

the input from the touch probe, as directed by the operator or programmer. The

machine then uses the X,Y,Z coordinates of each of these points to determine size and

position with micrometre precision typically.

A coordinate measuring machine (CMM) is also a device used in manufacturing

and assembly processes to test a part or assembly against the design intent. By

precisely recording the X, Y, and Z coordinates of the target, points are generated which

can then be analyzed via regression algorithms for the construction of features. These

points are collected by using a probe that is positioned manually by an operator or

automatically via Direct Computer Control (DCC). DCC CMMs can be programmed to

repeatedly measure identical parts, thus a CMM is a specialized form of industrial robot.

http://en.wikipedia.org/wiki/Industrial_robot



Plate 4.4 Shows Co-ordinate Measuring Machine

Table 4.4 Specification of Co-ordinate Measuring Machine

MAKE CARL ZIESS

ORIGIN GERMANY

Measuring range-„X‟, mm 550

Measuring range-„Y‟, mm 500

Measuring range-„Z‟, mm 450

Overall CMM size 1260×1340×2660

Max.wt of work piece 600

Applications Co-ordinate measuring, surface

scanning, Digitizing curve and

contour measurement

Note: Machine Hour Rate of co-ordinate measuring machine (CMM) - Rs1000/hr



Chapter 5

CASE STUDY

The manufacturing process and time estimation of following components:

1. BRACKET

2. WASHER

Figure 5.1 Bracket Model



5.1 Flow Chart of Manufacturing Bracket

Procedure

5.2 CNC Milling:

Most CNC milling machines are computer controlled vertical mills with the ability

to move the spindle vertically along the Z-axis. This extra degree of freedom permits

their use in diesinking, engraving applications etc. CNC machines can exist in virtually

any of the forms of manual machinery, like horizontal mills. The most advanced CNC

milling-machines, the multiaxis machine, add two more axes in addition to the three

normal axes (XYZ).

CNC MILLING

Stage Inspection

Wire EDM

Bench Work and

Fitting

Final Inspection

http://en.wikipedia.org/wiki/CNC



http://en.wikipedia.org/wiki/Multiaxis_machining



These machines have developed from the basic NC (NUMERIC CONTROL)

machines. A computerized form of NC machines is known as CNC machines. A set of

instructions (called program) is used to guide the machine for desired operations.

SETTING UP A CNC MACHINE:

Clean all surfaces, for example table, vise jaws and part very good with a

lint free cloth.



Load tools needed.



Load part in vise.



Set work fixture offsets. Make sure the machine is using the WFO that

the program will be using.



Adjust coolant lines so coolant can properly cool tools and wash

chips away.



Cycle Start.



Plate 5.2 Milling Operation



5.3 STAGE INSPECTION:

All parts are inspected in their respective stages while processing. This is known

as stage inspection. It helps in rectifying the mistake occurred during each operation.

Suppliers shall establish and maintain documented procedures for inspections

and tests of the equipment during manufacturing and assembly. The procedures shall

provide for the verification by inspections or tests, at appropriate points in the

manufacturing, that the characteristics of the item conform to the requirement specified

for that stage of the process. In general the verification should be made as close as

possible to the point of realisation of the characteristic.

The in-process verification may include:

Set-up and first piece inspection.

Inspection or test by machine operator.

Automatic inspection or test.

Fixed inspection stations.

Equipment shall be held until the required inspection and test has been completed.

Equipment shall not be released for further use until it has been verified and the

results of the verification are satisfactory.

5.4 Wire EDM:

Wire electrical discharge machining (WEDM), also known as wire-cut EDM and

wire cutting, a thin single-strand metal wire, usually brass, is fed through the work piece,

submerged in a tank of dielectric fluid, typically deionized water. Wire-cut EDM is

typically used to cut plates and to make punches, tools, and dies from hard metals that

are difficult to machine with other methods.



Wire EDM uses electro-thermal mechanisms to cut electrically conductive

materials. The material is removed by a series of discrete discharges between the wire

electrode and the workpiece in the presence of dielectric fluid, which creates a path for

each discharge as the fluid becomes ionized in the gap. The area where discharge

takes place is heated to extremely high temperature, so that the surface is melted and

removed. The removed particles are flushed away by the flowing dielectric fluids. The

wire EDM process can cut intricate components for the electric and aerospace

industries.

Plate 5.4 Wire EDM

5.5 Bench Work:

The bench work and fitting plays an important role in every engineering workshop

to complete and finish the job to the desired accuracy. The work carried out by hand at

the bench is called bench work. Whereas fitting is the assembling of parts together by

fitting, chipping, sawing, fore capping, tapping etc. necessary after the machine

operation. This may or may not be carried out of the bench.



The tools use in filling practice may be classified into the following group:

1) Holding tools

2) Striking tools

3) Measuring tools

4) Marking tools

5) Cutting tools

6) Scrapping tools

5.6 Holding tools (Vices): The holding tools are vice are required to hold the work

firmly. Following are the various types of vice for different purposes. Following are the

different types of holding tools:-

Bench Vice

Hand Vice

5.7 Striking tools (Hammers): The striking tools are hammers are used to strike the

job or tool. A hammer consists of a bead, striking face, peen and a shaft or handle.

5.8 Cutting Tools: The chief cutting tools used in fitting are cold, chisels, and files.

5.9 Method Filling: The following three methods are commonly used for filling.

Cross Filling

Straight Filling

Draw Filling



5.10 Final Inspection:

Final inspection is one in which the product manufactured is inspected completely after

completion. The contractor shall carry out all final inspection and testing in accordance

with the quality plan and/or documented procedures to complete the evidence of the

conformance of the finished equipment to the specified requirements. The quality plan

and/or documented procedures for all final inspection and testing shall require that all

specified inspections and tests, including those specified on receipt of equipment or in-

process, have been carried out and that the results meet specified requirements.

Inspections and tests procedures shall define:

The location where the inspection or test is to be performed (supplier premises)

The parameters to be measured.

The characteristics or functions that have to be verified.

The acceptance criteria, including any applicable standards or codes.

The requirements for special tools, fixtures, gauges, test set-ups and measuring

equipment.

Table5.1 Time Taken For Manufacturing Bracket

Operation Time in Minutes

CNC Milling 30

Stage Inspection 10

Wire EDM 30

Bench Work 15

Final Inspection 20

TOTAL Time Taken 105



2. Washer Model

Figure 5.2 Model of a WASHER



5.11 Flow Chart of Manufacturing Washer

PROCEDURE

5.12 TURNING:

Turning is a machining process to produce parts round in shape by a single point

tool on lathes. The tool is fed either linearly in the direction parallel or perpendicular to

the axis of rotation of the workpiece, or along a specified path to produce complex

rotational shapes. The primary motion of cutting in turning is the rotation of the

workpiece, and the secondary motion of cutting is the feed motion. A set of instructions

(called program) is used to guide the machine for desired operations.

Turning

Stage Inspection

Wire EDM

Bench Work

Final Inspection



5.13 Cutting fluids

Application of the cutting fluid is very important in a turning operation. The cutting

fluid should be applied in adequate quantity and at moderate pressure. The cutting

fluid should be directed on the work just above the point where it makes contact with

the tool.

5.14 Design Consideration for Turning Operation

• Parts should be designed so that can be fixtured and clamped in the work

holding devices

• Dimensional accuracy and surface finish specified should be as wide as possible

• Avoid sharp corners, tapers, and major dimensional variations in the part

• Cutting tools should be able to travel across work piece without obstruction

• Standard cutting tools, inserts, and tool holders should be used

Materials should be selected for their machineability.

Plate 5.14 Turning Process



5.15 STAGE INSPECTION:

All parts are inspected in their respective stages while processing. This is

known as stage inspection. It helps in rectifying the mistake occurred during each

operation.

5.16 Wire EDM:

Wire electrical discharge machining (WEDM), also known as wire-cut EDM and

wire cutting, a thin single-strand metal wire, usually brass, is fed through the work piece,

submerged in a tank of dielectric fluid, typically deionized water. Wire-cut EDM is

typically used to cut plates and to make punches, tools, and dies from hard metals that

are difficult to machine with other methods.

5.17 BENCH WORK:

The main operations commonly performed in bench work may be classified

1. Chipping

2. Filing

3. Grinding

4. Sawing

5. Marking

6. Tapping

5.18 FINAL INSPECTION:

Final inspection is one in which the product manufactured is inspected

completely after completion.



Table 5.2 Time Taken For Manufacturing Washer

Operation Time in Minutes

Turning 10

Stage Inspection 5

Wire EDM 10

Bench Work 5

Final Inspection 10

TOTAL Time Taken 40



CONCLUSION

It is necessary for an organization to compete in the fluctuating market and to be

profitable one. Profit always comes when goods are produced with maximum

productivity cost reduction proper training. This can be achieved through optimum use

of resources available in the organization and also by optimizing the time involved in

every element of the process. Non-productive time should be eliminated wherever

possible in order to increase productivity.

Through this training, is comprehensive understanding about the real industrial

working condition and practice. All these valuable experiences and knowledge is

acquired through the direct involvement in task but also through other aspects of the

training such as: work observation, interaction with collogues, superior and other people

related to the field. So in this way there is unlimited knowledge and many things to learn

here in this center.

The details about the EDNC Department, CNC Turning, Quality control, Laser

Department, Planning, CNC Milling and the machines used and respective

specifications operations are learnt.

Along with it detailed case study about the manufacturing process of Washer and

Bracket are learnt.

Documents

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