The problem is as follows...
A Cryogenic submerged pump from NIKKISO with flowrate 200m3/h used for propane circulation, which from the beginning has a noise like cavitation while there is no fluctuation in discharge pressure and electrical amp. It is necessary to mention this point that by limiting the suction valve the noise is solved.
Based on the pump document, the 3” nozzle on the top of the suction pot shall has permanent vent around 21 kg/min flowrate. This is while in reality, nozzle connected to flare system with normally closed valve.
So, if that noise is related to ventilation system, could anyone possibly tell us how should be the right network system and the destination of the vent.