CAPP for Machining Process

Manufacturing planning, material processing, process planning, process engineering, and machine routing are just a few of the titles given to the act of process planning.

Process planning is the function in a manufacturing facility that establishes which process & parameters are to be utilized to convert a piece part from its primary part form to final form, usually predetermined by design engineers. On the other hand, process planning could be defined as an act of preparing detailed work instructions to transform an engineering drawing to an ultimate part. Therefore, process planning forms a bridge between design and manufacture.

The detailed process plan consists of route, process parameters, processes, machines & tools needed for production. Though, when utilized in different industries & different shops, the process planning functions might involve various or all of the following activities :

1. Selection of machines and machining operations.

2. Sequencing of machining operations.

3. Raw material planning.

4. Setup requirements planning.

5. Selection of cutting tools.

6. Computation of machining parameters.

7. Design of jigs and fixtures.

8. Computation of processes time and cost.

9. Tool path planning and generation of NC part programs.

The act of process planning needs a significant amount of time & expertise which is not available readily. To manually prepare a process plan the following are some of the steps that have to be taken:

• Learn the overall shape of the part. Utilize this information to classify the part and decide the types of work stations needed.
• Learn the part drawing and try to recognize the manufacturing features and notes.
• Find out the best raw material shape to use if row stock is not given.
• Choose machines for each setup.
• Determine the rough sequence of operations necessary to generate all the features for each setup.
• Finalise the sequence of the operations resolute in the previous step.
• Check interference dependency among the operations.
• Select tools for each operation.
• Select or design fixtures for each setup.
• Evaluate the plan generated till this step and make necessary modifications.
• Select cutting parameters for each operation.
• Prepare the final process plan document.