How do we design suction and discharge line for motor or compressor for stress analysis.

Could you possibly make your question vaguer and more non-specific????

Start with a pencil and paper, and avoid drawing suction and discharge lines to and from the motor.

I suggest you'll try to read the discussions here,that will make you aware of the things that will affect your piping set-up's.
Use the search fucntion @ the right and search for +pump and you will have your hint.

Regards!