Oops....

Richard Ay,

Let me brief you our problem before I go in the detail analysis of piping and ask you to advise me some guidelines.

We have two fertilizer plants, plant-1 and plant-2. At our plant-1 we have two feed gas booster compressors (reciprocating), which were standby since 1981 and at plant-2 such compressor is not available. Plant-1 is designed in such a way that one compressor feeds that plant and other remains on standby.

We had decided to operate the second (standby) compressor to feed plant-2 after laying new suction and discharge lines. Currently both compressors are operating and independently feeding plant-1 and plant-2. We have to change the loads on compressors to 50%, 75% or 100% keeping in view the plant operations.

The problem is this; when the compressor of plant-2 is operated at 75% or 100% loads, it’s newly installed suction and discharge lines vibrate excessively. Vibration is excessive at the elbows, tees and dead pockets of PSVs & off takes. Most sever area is located near compressor and ~ 250 meters away from compressor.

We think piping vibration is mainly due to flow because at 50% compressor load the vibration is not so sever.

Please tell me, what kind of analysis I should perform to arrest the problem. Either harmonic analysis or acoustical analysis or any other analysis you recommend. I am using CAESARII.

Hope to have some guidelines to resolve the problem.