Describe procedural steps for developing CNC part programme.

Describe procedural steps for developing CNC part programme. 
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1 Answer

Answer :

Procedure for developing part program

There are two methods of part programming: manual part program and computer assisted part programming.

Manual part programming:

1. To prepare a part program using the manual method. The programmer writes the machining instructions on a special form called a part programming manuscript. The manuscript is a listing of the relative tool and work piece location.

2. The NC tape is prepared directly from the manuscript.

3. Define the axis coordinates in relation to the work part.

4. Define safe (target point) point and origin point (work zero).

5. The tape is inserted to read the first block in to the system.

6. The functions like machining, tool changing, spindle ON/OFF, coolant ON/OFF, program stop and tape rewinding are carried out as per the program.

OR

Computer- assisted part programming: This method is useful for most critical and complex parts. The part programmer and the computer are main tools in this method.

1.The part programmer first defines the work part geometry

2.He specifies the operation sequence and tool path

3.The computer interprets the list of part programming instructions, performs the necessary calculations to convert this into a detailed set of machine tool motion commands, and then controls a tape punch device to prepare the tape.

4. The tape is verified for accuracy.

5. The NC system machines (makes) the part according to the instructions on tape. 
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