A REPORT ON VOCATIONAL SUMMER TRAINING IN

ESCORTS PVT. LIMITED, FARIDABAD (HARYANA)

VIVEKANAND INSTITUTE OF TECHNOLOGY (EAST) JAIPUR

SUBMITTED TO: SUBMITTED BY:

MR. ASHEESH GOYAL SUNIL KUMARMECHANICAL DEPARTMENT ROLLS NO: 10EVVME206

MECHANICAL ENGG. FINAL YEAR

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PREFACE

This report is consisting brief knowledge of mine gained during training period in Escort Pvt. Ltd. Faridabad

With immense sincerity and pleasure I have completed my training in a well-developed plant with latest technology at escorts India limited. The purpose of training is that it helps one to get the required knowledge of manpower, actual work requirement, industrial and human relationships. The experience at the industry dealing with supervisors and actual work environment gave me some practical knowledge with respect to what we have studied theoretically from the curriculum books. This 30 days training gave me some knowledge of the things stated above of the industrial training and i have utilized the same to the best of my efforts.

Today, In competitive edge, choice of alternative is available in the market and consumers are also influenced by their informational and environmental clues that can persuade the consumer. So the usability patterns of ESCORT consumers become more important for company to understand and retain subscribe.

SUNIL KUMAR

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ACKNOWLEDGEMENT

It is matter of great pride for me that I got to complete my training company like Escorts Limited Agri Machinery Group. It is my sincere duty to express my deep sense of gratitude that supported and help me out in preparation of this report .

In modern technical field more interest and more importance is being given to practical knowledge of a particular student. For this reason these days’ workshops and training sessions are being conducted to keep the students technically sound. After my fourth semester i have undergone implant training at escorts India limited, Faridabad. I am extremely grateful to Mr. Mange ram Singla assistant engineer (maintenance department) and Mr. Rajesh Sharma (chief – manager Maintenance transmission p. U.) For their expert guidance and valuable support during my training period.

I was a pleasant to feel great experience working in this organization.

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BRIEF CONTENT

Contents page no

1. List of Figure 7

2. Management & Organization 8

3. Principle Activity 9

4. Escorts Limited Agri Machinery Group 11

5. Introduction 12

6. Background 13

7. Objectives of CNC 14

8. How CNC Works 15

9. Types of CNC Systems 17

10.Types of Monitoring Control Systems 17

11.CNC Machine Manufacturing Companies 18

12.Movements & Measurements of CNC Axis System 19

13.Programming of CNC 20

14.Configuration of CNC System 22

15.Modes of CNC 24

16.Compensation for M/C Accuracies 25

17.Tool Movement Modes 26

18.Work Handling Devices 27

19.Spindle Speed and Feed rate Selection 27

20.Programming Procedure 27

21.Methods of Milling 37

22.Milling Machine 38

23.Milling Cutters 39

24.Milling Process Performance 41

25.Conclusion 42

26. Reference 43

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List of figure

Figure page no

CNC MAZAK 1.1 15

Cutting example of CNC 1.2 16

Monitoring control system 3.1 18

CNC machine 4.1 19

Principle of turning 13.5.1.1 30

Turning operation on CNC 13.5.1.2 31

Aluminum flexor 13.50.1.3 32

Tool holder 13.5.1.4 32

Actuation system 13.5.1.4 33

Turning operation 13.5.1.6 35

Introduction to manufacturing process 13.5.2.1.1 36

Fundamentals of machining & machine tools 14.1 37

Milling operation 14.2.2 38

The Bridgeport CNC machine 15.1 39

Machine tool technology & manufacturing process 16.1 40

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MANAGEMENT AND ORGANISATION

The company board of directors consists of eminent industrialists, technical experts, financial advisors and administrators Mr. Rajang Nunda is the chairman and managing director of company .Mr. Anil Nunda is the vise chairman and managing director of the company. The day to day affairs of the executive directors of the company Mr. Nikhil Nunda manage the company assisted by a team of highly experienced professionals.

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PRINCIPLE ACTIVITIES

Till 1959, escorts limited, major activities were trading representing several leading overseas manufactures for sales of the products in India .progressively it entered into the field of manufacturing.

Its subsidiaries and associate companies are leading manufacturer of:

Agricultural tractorsMotor cyclesMobile cranesHarvestersPiston assemblyExcavator’s loadersShock absorbers

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ESCORTS LIMITED AGRI MACHINERY GROUP:

ESCORTS LIMITED AGRI MACHINERY GROUP

(AMG) CONSISTS OF THE FOLLOWING DIVISIONS:

FARMTRAC DIVISION

TRACTOR DIVISION

AGRI MACHINERY MARKETING DIVISION

LOCATION OF THE FACTORY:

(1) PLOT NO. 2,SECTOR – 13,FARIDABAD.

2) 115, SECTOR –24, FARIDABAD.

DATE OF INCORPORATION:

21.05.1969

DATE OF COMENCEMENT OF FIRST COMERICIAL PRODUCTION:

12.01.1971

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INTRODUCTION

A computer numerical control has a microprocessor based computer in the system to Store and process the data for the numerical control of motions of the machine tools. The NC system is the heart and brain of the CNC machine which enable the operation of the various machine members such as slides, spindles etc & also optimizes the matching with proper parameters involved in a matching operation.

CNC systems are constructed with an NC unit integrated with a PLC.The NC controls the spindle movement and the machine such as solenoids, relay coils etc. working together. The NC & PLC enable the machine tool to operate automatically.

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BACKGROUND

Development of CNC machines is an outstanding contribution to manufacturing industries. This has made possible to automate the machining process with flexibility to handle small to medium batch quantities in part production.

CNC technology was applied on basic metal cutting machines. Later CNC machines capable of performing multiple operations were developed.

Further, the concept of multi operations on the same machine was extended for cylindrical component machining and led to the development of turning centers and grinding centers.

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OBJECTIVES OF CNC

The main objective of CNC machines was to reduce cost for production of machined parts. This has been achieved by CNC by reducing programming time, including operational capability of the NC systems in place & making the entire machining process more users friendly. CNC also achieved this objective by reducing machining time, fixturing cost & tooling storage, including cutter life & lowering the skills required to automatically produce precision-machined components.

CNC has enabled accurate estimation of production process. CNC permitted more efficient shop scheduling, exact cost prediction higher facilities utilization, & more rapid return on equipment investment compared with less sophisticated machine control techniques or manual operations.

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1. HOW CNC WORKS

Computer Numerical control is a computer-assisted process to control general purpose Machines from instructions generated by processor and stored in a memory system or storage media for present as well as future use.

1.1Numerical Control means - Control by Numbers.

Controlling Machines by numerical command has brought about a revolution in manufacturing .CNC can be adapted to any kind of machine or process that requires direction by human intelligence. This text deals with CNC milling centers, turning centers, Boring Machines & Grinding Machines.

Fig.1.1 CNC MAZAK FF510

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CNC is a specific form of control system where position is the principal control variables numerical values, representing desired position of tools & symbolic information

corresponding to tools & secondary function, are recorded in some form where the information can be stored and revised indefinitely. Hard drives tape readers & other

converters transform this information into signals that ultimately operate servomechanism on each axis of machine whose motions are to be controlled. Today 32 & 64 -bit-bus

Microprocessors directly coupled with production machines control systems are expanding both the Applications and the basic definition of numerical control

Fig 1.2 cutting example on CNC

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2. TYPES OF CNC SYSTEMS:

CNC systems range from very simple to complex systems. Some of them are:

2.1. Point to Point Control systems2.2. Open loop control systems2.3. Continous Path control systems2.4. Closed Loop control systems

3. TYPES OF MONITORING CONTROL SYSTEMS:

3.1. C-Numeric system3.2. Fanuc system

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Fig 3.1. Monitoring control system

4. CNC MACHINE MANUFACTURING COMPANIES:

4.1. LAKSHMI MORI SEIKI4.2. KIRLOSKAR WARNER SWASEY4.3. H.M.T.

Fig. 4.1 CNC Machine

5. MOVEMENTS & MEASUREMENTS OF CNC AXIS SYSTEM

A system of rectangular coordinates also the “CARTESIAN COORDINATE SYSTEM" is the basis for measuring CNC machine axis movement. All point position are described in terms of distance ROM a common point called as ORIGIN.(X0.000,0.000,Z0.000)& measured along certain mutually perpendicular dimension line called AXIS. It is only necessary when describing geometry of part to locate every point of part within a frame work of 3 such MAJOR AXIS called X, Y, Z axis.

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6. PROGRAMMING OF CNC

6.1 CODED LANGUAGES:CNC has clearly moved ahead to conversational programming formats that have

advanced entire programming process to instruction of machine in everyday language, many part programs are stored in conventional program system formats such as G & M codes.These are:

N BLOCK Numbers (00-999)

6.1.1. G PREPATORY FUNCTIONS G00 RAPID TRANSVERSE G01 LINEAR INTERPOLATION G02 CIRCULAR INTERPOLATION CLOCKWISE G03 CIRCULAR INTERPOLATION ANTICLOCKWISE G04 DWELL PROGRAMABLE G10 OFFSET SETTING BY PROGRAM G20 INCH DATA INPUT G21 MM DATA INPUT G25 SUBROUTINE CALL UP G27 JUMP INSTRUCTIONS G28 REFRENCE POINT RETURN G40 TOOL NOSE RADIUS COMPENSATION CANCEL G41 TOOL NOSE RADIUS COMPENSATION LEFT G42 TOOLNOSE RADIUS COMPENSATION RIGHT G50 WORK CO-ORDINATE CHANGE G64 FEED MOTORS G65 DISC ACTIVATION G70 FINISHING CYCLE G71 MULTIPLE TURNING CYCLE G72 MULTIPLE FACING CYCLE G73 HIGH SPEED DRILLING CYCLE G78 THREADING CYCLE G81 DRILLING CYCLE G82 DRILLING CYCLE WITH DWELL G84 ROUGHING CYCLE LONGITUDNAL G85 REAMING CYCLE G88 ROUGHING CYCLE,FACING

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G90 ABSOLUTE VALUE PROGRAMMING G92 OFF SET OF REFERANCE POINT G94 FEEDING PER MIN. G95 FEED PER REVOLUTION G50 MAXIMUM SPINDLE SPEED

6.1.2. M MISCELLANEOUS FUNCTIONS M00 PROGRAMME STOP M01 OPTIONAL STOP M02 END OF PROGRAMME M03 SPINDLE ANTICLOCKWISE M04 SPINDLE CLOCKWISE M05 SPINDLE STOP M08 COOLENT OFF M09 COOLING ON M10 CHUCK CLOSE M11 CHUCK OPEN M12 LOW CHUCKING PR. M13 REGULAR CHUCKING PR. M18 TAILSTOCK IN M19 TAILSTOCK OUT M20 QUILL LEFT M21 QUILL RIGHT M22 REVERSE INDEX M23 FORWARD INDEX M28 PARTS CATCHER OPEN M29 PARTS CATCHER CLOSE M30 PROGRAM REWIND M36 CANCEL M37 M37 IGNORE UPTO SPEED FEED M40 DRY RUN WITHOUT SPINDLE M41 DRY RUN WITH SPINDLE M42 NORMAL MODE M48 CANCEL M39 M49 FEED RATE & SPINDLE SPEED M90 IN POSITION CHECK ON M91 IN POSITION OFF M92 SOFT JAW BORING M97 DISABLED

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M98 SUB PROG. CALL M99 SUB PROG. END

7. CONFIGURATION OF CNC SYSTEM:

A CNC system basically consists of the following:

7.1. CPU7.2. SERVO CONTROL7.3. OPERATOR CONTROL PANEL7.4. MACHINE CONTROL PANEL7.5. OTHER PERIPHERAL DEVICES7.6. PLC

CNC SYSTEM CONSISTS OF FOLLOWING PCBS:

7.1.1. POWER SUPPLY7.1.2. NC CPU7.1.3. MEMORY CARD7.1.4. COMMAND CARD7.1.5. FEEDBACK CARD7.1.6. OPERATOR PANEL7.1.7. NC COUPLING CARD7.1.8. PC COUPLING CARD7.1.9. INPUT/OUTPUT CARD7.1.10. PC CPU

7.1. CENTRAL PROCESSING UNIT:

This is the heart and brain of a CNC system. This translates the part program to position control signals. It also oversees the movement of control axis of spindle and the program signals corrective action is taken.

It also checks whether all the required conditions are within the control of the CPU if not then action of shutting down the machine is taken.

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7.1.1. POWER SUPPLY:

It is switching mode power supply it supplies all received dc voltage (12v, 15v, 5v) to other PCBs.

7.1.2. NC CPU:

The whole CNC circuit is divided into two portions:7.1.2.1. NC PART7.1.2.2. PC PART

NC (numerical controller part) -all numerical process/calculation take place.Central processing unit of NC part is called NC-CNC.

7.1.3. MEMORY CARD:

It is having three portion /area in one area. It store job machining program and stored on ram module.m/c operator requires to change it.In second portion it store m/c parameter. This portion also contains ram.In third portion it contain CNC system program and it is EPROM which is non-volatile.

7.1.4. COMMAND CARD:

This card executes axis command voltage (analog) and spindle command voltage (analog) to axis drive & spindle drive respectively.

7.1.5. FEEDBACK CARD:

This card receive feedback signal (digital) from feedback device for positional or rotational (rpm) calculation.

7.1.6. OPERATOR PANEL:

It connects CNC system to monitor (display unit) for displaying messages.

7.1.7. NC COUPLING CARD:

It interfaces NC part & PC part while compile data to assembling language.

7.1.8. PC COUPLING CARD:24

It connects peripheral units (tape reader, printer, floppy drive etc.) with CNC system. For downloading & uploading of m/c data, program.

7.1.9. INPUT/OUTPUT CARD:

It interfaces I/P devices (limit switch, proximity switches, overload etc.) & O/P devices (solenoids, counter, relay etc) of m/c side CNC system.

7.1.10. PC CPU:

It contain central processor unit of programmable control processor. Program of m/c logic is stored in EPROM module on this card.

8. MODES OF OPERATION:

CNC system can be operated in the following modes: 8.1. Manual mode8.2. Manual data input (MDI) made8.3. Automatic mode8.4. Set up mode8.5. Input/output mode

8.1. MANUAL MODE:

Here, movement of the machine slide can be done manually by pressing particular buttons. Selection of slide is done through an axis selector switch feedrate of slide movement is prefixed.

8.2. MANUAL DATA INPUT MODE:

Following operations can be performed: -

1. Editing of the part program stored in system memory.2. Building a new part program.3. Entering tool offsets in the system memory.

8.3. AUTOMATIC MODE:

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System allows execution of part program continuously. Part program is executed block by block while one block is read by the system, analyzed & kept ready for execution. Execution of the block can be continues or system will execute a block, stop execution of next block till it is initiated to do so. Selection of part program block by block (auto) or one at a time (single) is done through machine control panel.

Block retrace is allowed when cycle stop state is established. Part program execution can be resumed and its execution begins with the retraced block. This is important for tool inspection.

8.4. SET UP MODE:

The m/c can be referenced to its home position so that all the compensation can be applied. Part programs are generally prepared in absolute mode with respect to the m/c zero.

8.5. I/O MODE:

The part program, m/c setup data, tool offsets etc can be loaded into memory of the system from external sources like programming units or floppy drives.

9. COMPENSATION FOR M/C ACCURACIES:

Machine accuracy is the accuracy of the movement of the carriages and tables and is influenced by: -

1. The geometric accuracy of the alignment of the sideways.2. The deflection of the bed due to load3. Any temperature gradients existing through the machines.4. The accuracy of the screw thread of any drives, screws and the amount of backlash.5. The amount of twist of the shaft, which will influence the measurements of rotary transducers.

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10. TOOL MOVEMENT MODES:

In a CNC/NC machines, usually the tool moves with respect to the workpiece which remains at the same place. In some cases, example in a milling machine, the workpiece moves with respect to the tool. However, from programmer point of view this aspect hardly makes any difference as only relative motion between the tool and workpiece is important. While writing programs it is always assumed that tool moves with respect to the workpiece. For the second type of the machine, the workpiece automatically moves in the opposite direction so as to produce the desired relative motion.

Three types of motion control are used in a CNC machine:

10.1. Point to point placement10.2. Axial cut10.3. Contour cutting

10.1. POINT TO POINT PLACEMENT:

Such a control simply places the tool over desired location in desired sequence. There is no control over the speed of tool movement between the selected points which always a fast traverses. This type of control can be used in drilling, punching or similar operations where the location of tool at the timing of operation is important.

10.2. AXIAL CUT:

This control allows the tool to move along any major axes with desired speed. Therefore cutting along x, y, z axes is possible. Limitation being simultaneous motion along two axes is not possible so it can’t make angular cut.

10.3. CONTOUR CUTTING:

This is the most flexible but the most expensive type of control .It permits simultaneous control of more than one axes movement of the tool.

11. TOOL CHANGING DEVICES:

A number of tools may be required for making a complex part. In CNC machine, tools are changed through program instructions. Tools are fitted in tool magazine or drum. When a tool needs to be changed the drum rotates to an empty position, approaches the

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old tool and pulls it , then it again rotates to position the new tool, fits it and then retracts . This is typical tool changing sequence of an automatic tool changer.

Tool changing time is of the order of a few seconds this saves time and thus increases productivity.

11. WORK HANDLING DEVICES:

Some of the machining centers provide more than one separate pallets which can be of linear or rotary types. These pallets simply move or rotate or interchanging there positions on the machining table. While machining is being done on job kept on one pallet, the other pallets are accessible to the operator for clamping /unclamping raw material/ finished products. This saves a lot of material handling and set up time, resulting in higher productivity.

12. SPINDLE SPEED AND FEEDRATE SELECTION:

Let V = Cutting speed = Angular velocity of spindleN = RPMD = Diameter in mm

Then cutting speed V = D/2 = DN/60 in mm/sec.

A very high cutting speed reduces tool life due heat generation, whereas very low speed wastes machining time and may break the tool due to large cutting forces. So spindle speed should be properly chosen. Feed also should have proper value .a high value may break the tool due to large cutting forces, and surface finish also will be poor, where low wastes machining time. Usually for heavier cuts, slow RPM is recommended.

The largest depth of cut with highest feedrate safely possible is selected. This reduces cycle time and has a negligible effect on the tool life. In any case costwise reducing the machining time is usually more important than increasing the tool life.

13. PROGRAMMING PROCEDURE:

The basic steps involved in an NC/CNC programming are:

13.1. Process planning.13.2. Part programming.13.3. Program entry.

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13.4. Program verification.13.5. Production.

13.1. PROCESS PLANNING:

The design /development department of manufacturing industry design a path and prepare its detailed drawing. For a simple part, three or even two orthographic views are sufficient to describe it fully.

After the drawing is finalized the programmer carries out the task of process planning. Process planning is the procedure of deciding what operations are to be done on the component, in what order and with what tooling and work holding facilities.

13.2. PART PROGRAMMING:

The next step after finalizing the machining scheme is part programming the first step in part programming is to define a component zero point at a convenient location on the part this become the origin of the co-ordinate system for programming. The axis remains parallel to the machine axis. In the program, all the co-ordinates in the part drawing are specified with respect to this co-ordinate system.

The program must follow the standard being used by the MCU (called simply controller also). FANUC controller has now become industry standard. Program written for a specific controller can’t be used on a different controller. Where some of the commands (G and M codes) may have the different meanings. This text follows FANUC standard. So the given program can only be used on a FANUC machine.

13.3. PROGRAM ENTRY:

After the program is ready it needs to be transmitted to the MCU. The most common input medium has been one-inch wide tape over the past 40 years. Even today it is being used in some machines, though they have now being more or less completely replaced by the other media such as floppy disk.

Most of the CNC machines provide both on line and offline software for program coding and simulation. Since programming takes substantial amount of time, one can’t afford to engage a production machine for this purpose. Hence offline software is invariably used for programming using a standalone computer. These software provide necessary

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editing features to make correction in the typed program once the program is ready and verified, it may be transferred to the machine through floppy disk

13.4. PROGRAM VERIFICATION:

Once the part program is entered on the machine and execution command is given for producing the part, the operator has no control over machine movements except minor modifications such as over riding spindle RPM and feed. In case of any undesired movement of tool, the machine can only be stopped through the emergency stop switch or the reset button .Any carelessness may result in serious damage to the machine so the program must be thoroughly verified before executing it on the machine for production.

13.5. PRODUCTION:

Production is the simplest part of a CNC procedure. The person responsible for this need not be a skilled worker. In fact one semi skilled worker may handle several CNC machines on the shop floor.

CNC operator has to first check the tool position on the tool turret.If there is any discrepancy from the part program; he may either change tool positions on the turret or modify the program to correct the tool index no.

The next thing to be done by the operator is tool offsetting. Infact as already mentioned the details of tool offset can be stored on a floppy disk, which can be reloaded in case of power failure or for a subsequent use on the machine

Finally the operator has to check coolant level, air pressure extra.If every thing is okay he give the execution command for production.

In production many type of operation can performed on CNC such as:

13.5.1. Turning13.5.2. Milling13.5.3. Drilling etc.

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13.5.1. TURNING:

What is turning?

Turning is the machining operation that produces cylindrical parts. In its basic form, it can be defined as the machining of an external surface:

1. with the work piece rotating,

2. with a single-point cutting tool, and

3. With the cutting tool feeding parallel to the axis of the work piece and at a distance that will remove the outer surface of the work.

Taper turning is practically the same, except that the cutter path is at an angle to the work axis. Similarly, in contour turning, the distance of the cutter from the work axis is varied to produce the desired shape.

Even though a single-point tool is specified, this does not exclude multiple-tool setups, which are often employed in turning. In such setups, each tool operates independently as a single-point cutter.

Fig 13.5.1.1 principle of turning

Nowadays, more and more Computer Numerical Controlled (CNC) machines are being used in every kind of manufacturing processes. In a CNC machine, functions like program storage, tool offset and tool compensation, program-editing capability, various degree of computation, and the ability to send and receive data from a variety of sources, including remote locations can be easily realized through on board computer. The computer can store multiple-part programs, recalling them as needed for different parts. A CNC turret lathe in Michigan Technological University is shown in the following picture.

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Fig 13.5.1.2 turning operation on CNC

Our Equipment:

Our Actuator/Flexor system uses a magneto strict material known as Terfenol - D to provide nearly instantaneous elongation. The cutting tool is mounted in an aluminum flexor, which provides motion similar to a hinge, but without friction or backlash.

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Fig 13.5.1.3 cutting tool mounted on aluminum flexor

Fig 13.5.1.4 tool holder

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We have a Pentium based pc that is used to control the elongation of the actuator, a Power Amplifier to provide the necessary current to the actuator, and a compliment of sensors,

including: Load Cells, Accelerometers, a displacement sensor, and other equipment. The total actuation system has a bandwidth of 1.8 kHz.

Fig

13.5.1.4 Actuation system

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FIG 13.5.1.5

Here is a picture of the actuator in operation. The material being cut is an aluminum alloy. The actuator/flexor system is mounted to the tool holder turret of MTU's CNC lathe.

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Fig 13.5.1.6 turning operation

13.5.2. MILLING:

WHAT IS MILLING?

Milling is the process of cutting away material by feeding a work piece past a rotating multiple tooth cutter. The cutting action of the many teeth around the milling cutter provides a fast method of machining. The machined surface may be flat, angular, or curved. The surface may also be milled to any combination of shapes. The machine for holding the work piece, rotating the cutter, and feeding it is known as the Milling machine.

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CLASSIFICATION OF MILLING:

13.5.2.1. PERIPHERAL MILLING:

In peripheral (or slab) milling, the milled surface is generated by teeth located on the periphery of the cutter body. The axis of cutter rotation is generally in a plane parallel to the work piece surface to be machined.

Fig 13.5.2.1.1 Introduction to Manufacturing Processes

13.5.2.2. FACE MILLING:

In face milling, the cutter is mounted on a spindle having an axis of rotation perpendicular to the work piece surface. The milled surface results from the action of cutting edges located on the periphery and face of the cutter.

13.5.2.3. END MILLING:

The cutter in end milling generally rotates on an axis vertical to the work piece. It can be tilted to machine tapered surfaces. Cutting teeth are located on both the end face of the cutter and the periphery of the cutter body.

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14. METHODS OF MILLING:

14.1. UP MILLING:

Up milling is also referred to as conventional milling. The direction of the cutter rotation opposes the feed motion. For example, if the cutter rotates clockwise, the work piece is fed to the right in up milling.

Fig 14.1 (Fundamentals of Machining and Machine Tools)

14.2. DOWN MILLING:

Down milling is also referred to as climb milling. The direction of cutter rotation is same as the feed motion. For example, if the cutter rotates counterclockwise, the work piece is fed to the right in down milling.

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fig 14.2.1 Fundamentals of Machining and Machine Tools

The chip formation in down milling is opposite to the chip formation in up milling. The figure for down milling shows that the cutter tooth is almost parallel to the top surface of the work piece. The cutter tooth begins to mill the full chip thickness. Then the chip thickness gradually decreases.

Other milling operations are shown in the figure.

Fig 14.2.2 milling operations

15. MILLING MACHINE:

The milling machine is one of the most versatile machine tools in existence. In addition to straight milling of flat and irregularly shaped surfaces, it can perform gear and

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thread cutting, drilling, boring and slotting operations which are normally handled on machine tools designed specifically for these specific operations

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Fig 15.1 the Bridgeport CNC Milling Machine

16. MILLING CUTTERS:

A milling cutter is a cutting tool that is used on a milling machine. Milling cutters are available in many standard and special types, forms, diameters, and widths. The teeth may be straight (parallel to the axis of rotation) or at a helix angle. The helix angle helps a slow engagement of the tool distributing the forces .The cutter may be right-hand (to turn clockwise) or left-hand (to turn counterclockwise).The figure shows a typical end milling cutter.

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FEATURES OF MILLING CUTTERS:

Fig 16.1 Machine Tool Technology and Manufacturing Processes

Fig 16.2 insert used in milling cutter

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17. MILLING PROCESS PERFORMANCE:

Calculation of machining parameters in End Milling and Face Milling Some important machining parameters like machining time, material removal rate, power etc. are calculated for face milling and end milling processes.

ADVANTAGES OF CNC MACHINES:

1. Higher flexibility2. Increase in productivity3. Consistency in quality4. Reduction in scrap rate5. Reliability in operation6. Reduction in manpower7. Reduction in non-productive time8. Shorter cycle time9. Higher accuracy10.Reduce lead time11.Lesser floor space12.Operational safety13.Machining of advanced materials14.Reduction in material handling

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CONCLUSION:

According to the analysis it has been assessed that the people have more faith in ESCORT, being a govt. concern, which can capture the maximum no of automobile market. But at the same time we should not ignore the growing popularity of other tractor manufacturing company.

These are the main competitor of ESCORT in Faridabad & Gurgaon city. At present not a tough competition between all these but in the fourth coming year there will be a tough competition between all these companies.

According to my survey I have taken the conclusion about the new scheme is that the price of tractor & machinery should not so high that a farmer can’t afford it easily. But according to me is that there should be a good product at lower cost that fulfills the requirement of a farmer or the owner of the product. Company should have try to attract the consumer’s through the quality service and there supply services or some new attractive schemes etc. for standing in the market competition.

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REFERENCEwww.google.comwww.escort.co.in

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