The pump cavitated, although here was excessive suction head available
The pump cavitated, although here was excessive suction head available
(OP)
My pump is cavitating even though there is enough NPSHA. What are some possibilities for this anomaly?





RE: The pump cavitated, although here was excessive suction head available
RE: The pump cavitated, although here was excessive suction head available
The pump is not suffering suction cavitation, it is being subjected to pre-rotation of the inlet flow.
RE: The pump cavitated, although here was excessive suction head available
Johnny Pellin
RE: The pump cavitated, although here was excessive suction head available
Possible conclusion to my ordeal... I got an in between bearing pump which takes suction (2 impeller eyes) 16-20ft below the vessel. The suction piping has a total run of 20ft with 3 90deg ells. the pump is running below 70%of the flow at BEP. (This has never been an issue since the pump has run at lower flows). however, there has been changes on the process conditions. The vapor space pressure in the vessel was reduced and the process temp has gone up. the adverse affects of the change (vapor pressure of the liquid went up and vapor space pressure decreased) resulted in the reduction of the NPSHa.
Thanks fellas for your speedy reply...
RE: The pump cavitated, although here was excessive suction head available
As you haven't had any problems until changes were made in the operating conditions it seems obvious that is the problem.
RE: The pump cavitated, although here was excessive suction head available