Friday, 26 April 2019

# 20 G-Codes and M-Codes(14) of CNC Part Programming-Especially for GATE Exam

20 G-Codes and M-Codes(14) of CNC:Part programming is not a language programming but it is a coded programming method used for writing the programs for manufacturing of given components.Part Programming uses standard codes and code means the name given for the program written for a standard measurement of tool. G-Codes and M-Codes are used in part programming.G-Codes Stands for General Purpose Codes and M-Codes Stands for Miscellaneous or Machine Codes.Minimum 2 marks will come from G-Codes and M-Codes region.Therefore,In this article,I will be explaining about 20 G-Codes and M-Codes in a detailed manner.

## 20 G-Codes and M-Codes of CNC Part Programming:

The G-Codes and M-20 G-Codes and M-Codes(14) of CNC Part Programming-Especially for GATE Exam follows.

1.G 00 : Rapid Traverse: G00 Code stands for Rapid Traverse.It means that whenever the tool required to travel ideally without removing any material.It is required to travel at maximum possible speed,in such cases G00 Code will be used.

2.G 01:Linear Interpolation Whenever the tool required to travel in a straight line path,G 01 Code will be used.

3. G 02:Circular Interpolation (Clock wise)

4.G 03: Circular Interpolation (Counter Clock wise) Whenever the tool is required in a contour path,G 02 or G 03 will be used.

5.G 04: Dwell Dwell indicates temporary stoppage of tool in the machine for a specified duration.

6.G 05:Hold Hold indicates stoppage of tool in the machine for Unlimited Duration. Ex: G04 F120 Here F120 indicates temporary stoppage duration in seconds.

7.G 08: Acceleration Whenever the machine is getting started,it has to start at a lowest velocity and reaches to the maximum velocity in a specified duration.For this,the G 08 Code will be used.

8.G 09: Retardation Whenever the tool is nearing to the destination,it has to reduce its velocity so that it is possible to stop the tool exactly whenever it is required.For this G 09 Code will be used. G 08 and G 09 are the Default codes used in part programming.

9.G 17: Movement of Tool in XY Plane

10.G 18 : Movement of Tool in YZ Plane

11.G 19 : Movement of Tool in ZX Plane

12.G 33: Thread Cutting with Constant Pitch.

13.G 34: Thread Cutting with Increasing Pitch.

14.G 35 : Thread Cutting with Decreasing Pitch.

15.G 41: Tool Radius Compensation Left

16.G 42: Tool Radius Compensation Right

17.G 70: English Programming (Inches)

18.G 71: Metric Programming (mm)

19.G 90: Absolute Mode If each and every movement of the tool is indicated with reference to the only one single reference point called as machine reference point named as Absolute mode of Programming.

20.G 91: Incremental Mode. If the Present position of the tool is taken as reference point for programming the next position of the tool called as Incremental mode of programming. These are the 20 G-Codes of CNC Part Programming.

Note: Even though incremental mode of programming is easy to write and modify but according to Indian conditions,we prefer to use absolute mode of programming only because during running of the program for producing the components if the power failure occurs,after restoring the power,it is very easy to identify where the program has got stopped if it is a absolute mode of program. The M Codes required in Part Programming are as follows which are very important for GATE Exam.

14 M Codes that GATE Student must know in CNC programming

These are the 20 G-Codes and M-Codes(14) of CNC Part Programming.The Aim of speaking about these codes is to solve the problems related to the CNC programming in GATE Exam in an effective manner.