Tata Steel is one of the largest steel producers in the world, established in 1907 in Jamshedpur, India. Numerical control (NC) and computer numerical control (CNC) allow machines to be controlled by programmed sets of instructions, enabling precise and repeatable machining of complex geometries. A CNC system consists of a part program, program input device, machine control unit, drive system, machine tool, and feedback system working together to automate production. CNC machines offer advantages like increased accuracy and reduced human errors compared to manual machining.

1. INDUSTRIAL TRAINING
AT
TATA STEEL
JAMSHEDPUR
GOVERNMENT ENGINEERING COLLEGE
AJMER
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PRESENTED BY:
MD. FAIZAN
VII SEM. ( EIC)
COLLEGE NO. 08EI28

2. INTRODUCTION
 Established in 1907 by J.N.Tata.
 Formerly known as TATA IRON AND STEEL
COMPANY LIMITED(TISCO)
 World’s 6th Largest Steel making company.
 28.1 million p.a. of crude steel production
capacity.
 Products: Steel, Blast furnaces,EOT cranes,
Automobiles, Machines etc.
 Headquartered in Jamshedpur, Jharkhand and
registered office in Mumbai ,India
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3. INTRODUCTION OF NC AND CNC
 NC stands for Numerical Control
 CNC is self contained NC system with a
dedicated computer.
 Control a machine by programs or set of
instructions.
 Widely used for manufacturing system like
Machine Tools, Welders, And Laser Beam
Cutters
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4. Motivation and Uses
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 To manufacture complex curved geometries
in 2D or 3D was extremely expensive by
mechanical
 Machining components with repeatable
accuracy
 Unmanned machining operations

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ADVANTAGES DISADVANTAGES
 Easier to program
 Easy storage of existing
programs
 Easy to change a program
 Avoids human errors
 NC machines are safer to operate
 Complex geometry is produced
as cheaply as simple ones
 Usually generates closer
tolerances than manual machines
 Increase in electrical
maintenance.
 Increase in initial investment.
 Training of existing workforce.
 Not cost-effective for low-level
production on simple parts

6. CNC SYSTEM ELEMENTS
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A typical CNC system consists of the
following six elements
 Part program
 Program input device
 Machine control unit
 Drive system
 Machine tool
 Feedback system

7. NC SYSTEM ELEMENTS
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8. OPERATIONAL FEATURES OF CNC
MACHINES
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9. PART PROGRAM
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 A part program is a series of coded
instructions required to produce a part as
in the following example
 N10 G01 X5.0 Y2.5 F15.0
| | | | |
| | | | Feed rate (15 in/min)
| | | Y-coordinate (2.5")
| | X-coordinate (5.0")
| Linear interpolation mode
Sequence number

10. BLOCK
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Block is the smallest part of the programme.
The block is composed of words and always
ends with the characters “END OF BLOCK”.
A block contains the following WORDS :
Sequence / Block number __________________________ N
Preparatory Functions _____________________________ G
Dimensions _____________________________________ X, Y, Z
Arc Center Offset _________________________________ I, J, K
Feed Function ___________________________________ F
Speed Function __________________________________ S
Tool Function ____________________________________ T
Miscellaneous Function ____________________________ M

11. PROGRAM INPUT DEVICE
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 The program input device is the
mechanism for part programs to be
entered into the CNC control.
 The most commonly used program input
devices are keyboards, punched tape
reader, throgh RS 232 serial ports and
networks.

12. MACHINE CONTROL UNIT
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It is used to perform the following
functions:
 Read coded instructions
 Decode coded instructions
 Implement interpolations (linear, circular,
and helical) to generate axis motion
commands
 Feed axis motion commands to the amplifier
circuits for driving the axis mechanisms
 Receive the feedback signals of position and
speed for each drive axis
 Implement auxiliary control functions such
as coolant or spindle on/off, and tool change

13. TYPES OF CNC CONTROL
SYSTEMS
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 Open-loop control
 Closed-loop control
DRIVE SYSTEM
A drive system consists of :
amplifier circuits,
stepping motors or servomotors
ball lead-screws

14. Open Loop v/s Closed Loop controls
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15. Elements of CNC machines
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1. Terminal Connector (TC)
The Terminal Box provides easy, reliable connections
for wires and cables

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2. POTENTIOMETERS
FEEDBACK DEVICES

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3. Limit Switches
 Interlocks a mechanical motion or
position with an electrical circuit.
 Most common limit switch is the
single-pole contact block with
one NO and one NC set of
contacts

18. 4. PUSH BUTTONS
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 Simple switch
mechanism for
controlling a process.
 Colour coded: red(stop)
green (start)

19. 5. CONTACTOR
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Used for switching a power
circuit of higher ampere
ratings.
Electromagnet provides
driving force to close the
contact.
Enclosed in insulating
material for protection.

20. Conclusion
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• Learned about the basic electrical
components.
• Learn different circuits used in CNC
machine.
• Introduction to CNC machine.
• Basic programming of CNC machine.

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