QualityTime
Civil/Environmental
- Apr 14, 2010
- 458
thread403-240597
It most likely is not cavitation. Cavitation means you do not have enough NPSHa. I will bet that the water levels in the cooling tower is not set correctly and you are getting air in the pump as a result. It may sound like cavitation and over the long term it will cause the same damage to the same area of the pump impeller as cavitation would. But because the cause is different the solution is different. If it is cavitation and you throttle the discharge of the pump the cavitation noise should dissapear. If it does not...it is air entraiment in the water from the cooling tower. Another way to check if there is a problem with air is by putting your ear up against the piping. It should sound full
A well know manufacuturer of cooling towers has conflicting documents on what the working water levels should be. I had to point that out to them and their local representative and I live in a major metropolitan area. They did not even know that. Their local representative who has repped them for an awful long time were setting the cooling water water levels to the incorrect document. Once I got the two parties to talk to each other they raised the working water level in my tower to the proper level mentioned in the correct document and the air problem dissappeared. Destroyed a number of pump couplings...up until the problem was solved
It most likely is not cavitation. Cavitation means you do not have enough NPSHa. I will bet that the water levels in the cooling tower is not set correctly and you are getting air in the pump as a result. It may sound like cavitation and over the long term it will cause the same damage to the same area of the pump impeller as cavitation would. But because the cause is different the solution is different. If it is cavitation and you throttle the discharge of the pump the cavitation noise should dissapear. If it does not...it is air entraiment in the water from the cooling tower. Another way to check if there is a problem with air is by putting your ear up against the piping. It should sound full
A well know manufacuturer of cooling towers has conflicting documents on what the working water levels should be. I had to point that out to them and their local representative and I live in a major metropolitan area. They did not even know that. Their local representative who has repped them for an awful long time were setting the cooling water water levels to the incorrect document. Once I got the two parties to talk to each other they raised the working water level in my tower to the proper level mentioned in the correct document and the air problem dissappeared. Destroyed a number of pump couplings...up until the problem was solved
