BHEL training and project report on cnc

1. Industrial training report
At
Khailar Jhansi
In partial fulfillment of the requirement for the course of Diploma in Mechanical
Engineering
Submitted By
Savir Mansoori
173200256

2. Certificate

3. Self assessment of industrial Training By student
• Savir Mansoori
• BHARAT HEAVY ELECTRICALS LIMITED.
• Khailar, Jhansi, Uttar Pradesh 284120
• 17 June 2019 to
• 20 July 2019
• I hereby declare that,I have learnt following skills with during my industrial
training.
• Date-01/07/2019.
• 173200256.

4. Acknowledgement
The internship opportunity I had with [Bharat Heavy Electricals Limited ] was a
great chance for learning and professional development. Therefore, I consider
myself as a very lucky individual as I was provided with an opportunity to be a part
of it. I am also grateful for having a chance to meet so many wonderful people and
professionals who led me though this internship period.
Savir Mansoori
173200256

5. BHEL
 BHEL is India's largest engineering and manufacturing Enterprise.
 Established in 1956.
 Got 'Maharatna' status by the Government of India on 1 February 2013.
 More than 150 project sites across India and abroad.
The company has added more than 1,24,000 MW to the country's installed power
generating capacity so far.

6. Products
 Locomotive Plant
 Boilers Auxiliaries Plant.
 Transformer.
 Power electronics.
 Electrical machines.
 Insulator Plant.
 Oil field equipment.

7. History
 The first NC machines were built in the 1940s and 1950s by Prof. John T Parson.
 US Air Force teamed up with MIT to develop a programmable milling machine
(1949).
 CNC machine came into existence after evolution of computer around 1980.
 Modern CNC Machine are improving further as the technology is changing with
a variety of functions according to applications.

8. Introduction of CNC Machine
 Numerical control is a method of automatically operating a manufacturing
machine based on a code of letters, numbers, and special characters.
 The numerical data required to produce a part is provided to a machine in the
form of a program, called part program or CNC program.
 The program is translated into the
appropriate electrical signals for input to
motors that run the machine.

9. Need of CNC
• Increase production rate.
• Stabilize manufacturing costs.
• Highly accurate over traditional machines.
• More operations can be performed
with each setup Repeatability,
reduced scrap loss, and high
production rates.

10. Types of CNC Machine
There are many different types of CNC Machines used in industry, Such as:
 Mills and Machining Centers.
 Lathes and Turning Centers.
 Drilling Machines.
 Wire cut Machines.
 Flame and Laser-Cutting Machines.

11. Block Diagram

12. Working of CNC Machine
All computer controlled machines are able
to accurately and repeatedly control
motion in various directions. Each of
these directions of motion is called an
axis. Depending on the machine type
there are commonly two to five axes.

13. Open loop and close loop control
Open and closed loop describes the control process of a system. Open loop refers to
a system where the communication between the controller system and the motor is
one way. ... Stepper motors are able to operate in an open loop system while servo
motors are not, for CNC applications at least.

14. Elements of CNC Machines
 Input Device.
 Machine Control Unit.
 Machine Tool.
 Driving System.
 Feedback Devices.
 Display Unit.

15. Input Devices
The program input device is the means for part program to be entered into the CNC control.
Three commonly used program input devices are punch tape reader, magnetic tape reader,
and computer via RS-232-C communication. ( 1.3 ) Machine Control Unit:
The machine control unit (MCU) is the heart of a CNC system.
Input devices in CNC are as follows:
 Floppy disk drive
 USB Flash Drive.
 Serial communication.

16. Machine Control Unit
The machine control unit (MCU) is the heart of a CNC system. It is used to perform the
following functions:
Data processing unit.
 On receiving a part programme, the DPU firstly interprets and encodes the part
programme into internal machine codes.
 Control Loop Unit.
Data from the DPU are converted into
electrical signals in the CLU to control the
driving system to perform the required motions.

17. Driving System
 This system usually uses electric motors although hydraulic motors are sometimes used
for large machine tools.
DC servo motor
 The principle of operation is based on the rotation of an armature winding in a
permanently energized magnetic field.
Stepper Motor.
A stepper motor is a device that
converts the electrical pulses into
discrete mechanical rotational
motions of the motor shaft.

18. Feedback Devices
Position feedback devices are by far the most common, although some systems also
employ velocity or acceleration feedback devices. An encoder is a position feedback
device that measures rotary or linear motion of the motor (or other element in the
system).
Positional Feed Back Devices
A linear transducer is a device mounted on the machine table to
measure the actual displacement of the slide.
Velocity Feedback Device
 The actual speed of the motor can be measured in terms of voltage
generated from a tachometer mounted at the end of the motor shaft.

19. Display Unit
The Display Unit serves as an interactive device between the machine and the operator.
 Operator Control Panel To facilitate two-way communication between the user, CNC
system and the machine tool.
 Video Display Unit (VDU).
 Keyboard.
Machine Control Panel (MCP) It is
the direct interface between operator
and the NC system, enabling the
operation of the machine through
the CNC system.

20. CNC Programme Basics
 CNC instructions are called part program commands.
When running, a part program is interpreted one command line at a time until all lines are
completed.
Commands, which are also referred to a
blocks, are made up of words
which each begin with a letter address
and end with a numerical value.
G Codes for CNC

21. Advantages of CNC
 Easier to program.
 Easy storage of existing programs.
Easy to change a program.
Avoids human errors.
CNC machines are safe to operate.
Complex geometry is produced as cheaply as simple ones.
Usually generates closer tolerances than manual machines

22. Challenges
 Costly setup.
 skilled operators
 Computers, programming knowledge required.
 Maintenance is difficult

23. Applications
In these industries the CNC machines are
used for various machining operations like
shearing, flame or plasma cutting, punching,
laser cutting, forming, and welding and many
other applications. To bring the plates to their
final shape CNC lasers and CNC plasma
cutters are used commonly.

24. Conclusion
 The advantage of a CNC system are that the operation of a conventional machine
is removed and the part production is made automatic.
 It reduces the labor work and hence highly efficient in the manufacturing process.
 BHEL generally uses CNC machines to achieve its manufacturing targets. For
manufacturing works of large scale it is very difficult to work with manual
machines as they are time consuming. CNC machines have their wide scope
because they are easy to handle, the work becomes easier and jobs are done with
perfection.