Features and characteristics of CNC Machine

1. PRESENTATION ON
CHARACTERISTIC FEATURES OF CNC MACHINE
SUMBITTED TO: SUMBITTED BY:
Dr. MANU SRIVASTAVA ROLL NO.- 1314340102
SHUBHAM JAISWAL ME-

2. CNC MACHINE

3. CNC (Computer Numeric Control)
Computer Numeric Control (CNC) is the automation of machine
tools that are operated by precisely programmed commands encoded
on a storage medium (computer command module, usually located
on the device) as opposed to controlled manually by hand wheels or
levers, or mechanically automated by cams alone.
In modern CNC systems, end-to-end component design is highly
automated using computer-aided design (CAD) and computer-aided
manufacturing (CAM) programs.

4. HISTORY
1955 - US Air Force define a need to develop a machine tool
capable of machining complex and close tolerance aircraft parts.
1959 - MIT is the contractor and builds the machine for the project.
MIT announces Automatic Programmed Tools (APT) programming
language
1960 - Direct Numerical Control (DNC). This eliminates paper
tape and allows programmers to send files directly to machine tools
1980’s - CNC machine is introduced. Unix and PC based systems
1997 - PC- Windows operating system is attached to CNC.

5. TYPES OF CNC MACHINE
 Turning Centers
 Milling Centers
 Vertical Machining Centers (VMC)
 Horizontal Machining Centers (HMC)
 Drilling Machines
 EDM Machines
 Laser-Cutting Machines

6. TURNING CENTERS

7. MILLING CENTERS

8. VMC MACHINE

9. Vertical Machining Centers (VMCs)
 Spindle in a vertical orientation.
 VMCs are high-precision
 Used for tight-tolerance

10. HMC MACHINE

11. HMC MACHINE
 Spindle in a horizontal
orientation.
 Horizontal orientation
encourages chips to fall away.
 HMCs are high-precision.
 Used for tight-tolerance.

12. How CNC Works
 Controlled by G and M codes.
 These are number values and co-ordinates.
 Each number or code is assigned to a particular operation.
 Typed in manually to CAD by machine operators.
 G & M codes are automatically generated by the computer
software.

13. Common Format of a Block

14. Programming Key Letters
 O - Program number
 N - Sequence number
 G - Preparatory function
 X - X axis designation
 Y - Y axis designation
 Z - Z axis designation
 R - Radius designation
 F – Feed rate designation
 S - Spindle speed designation
 H - Tool length offset designation
 D - Tool radius offset designation
 T - Tool Designation
 M - Miscellaneous function

15. Table of Important G codes
 G00 - Rapid Transverse
 G01 - Linear Interpolation
 G02 - Circular Interpolation (CW)
 G03 - Circular Interpolation (CCW)
 G20/G70 - Inch units
 G8 - Cancel canned cycles
 G81 - Drilling cycle
 G82 - Counter boring cycle
 G83 - Deep hole drilling cycle
 G90 - Abosolute positioning
 G91 - Incremental positioning

16. Table of Important M codes
 M00 - Program stop
 M01 - Optional program stop
 M02 - Program end
 M03 - Spindle on clockwise
 M04 - Spindle on counterclockwise
 M05 - Spindle stop
 M06 - Tool change
 M08 - Coolant on
 M09 - Coolant off
 M10 - Clamps on
 M11 - Clamps off
 M30 - Program stop, reset to start

17. Operator Panel

18. Tools of Machine

19. Tools of Machine
 Posses hardness and strength at
high temperatures
 Able to withstand when heat is
generate
 Angle of the cutting face
 Flute width, number of flutes,
teeth, and margin size

20. CUTTING FLUIDS / COOLANT
 Lubricating during cutting process.
 Cooling the work piece at high cutting
speeds.
 Improving tool life.
 Improving surface finish.
 Flushing away chips from the cutting
zone.
 Corrosion protection of the machined
surface.

21. Advantages
 High Accuracy.
 Production rate is very high.
 Complex surfaces need to be machined.
 Flexibility in job change , automatic tool settings.
 More safe , higher productivity , better quality.
 Less paper work , faster prototype production.

22. Disadvantages
 Costly setup.
 Skilled operators.
 Computers , Programming knowledge required.
 Maintenance is very difficult.

23. THANK YOU