Cavitation, Why?

[791018]

I found many pitted on our Maxidur 3 blade Dredgepump Impeller, also at surface of inner pump casing. Standard pressure at suction ( refer to iHC standard) is average between 4 to 5 bar, and its achieved. Pitted holes due to cavitation cause the impeller running out of balance, and lately will damaged the impeller shaft in the gearbox. we've done the stability test with the orifice, and its ok. Suction and discharge pressure was also balanced in their range. Pipeline distance was also within the range. what other factor should i check?

 

[whizzz]

have you do your homework? where's your NPSHa calc so we can discuss here

 

[25362]

When the pipe friction is lower than estimated, the system curve may intersect the pump curve at its farther end resulting in overcapacity, excess horsepower, pump wear and even cavitation depending upon far out on the its curve is the pump running.

There is an article titled Slurry pump selection and application by Dalstad, in the ChE issue of April 25, 1977, that may be of help.

 

[bulkhandling]

791018,

Cavitation, why?

If you've figured out the cause, please post it here.

If you still haven't figured out, hire a pump engineer. Your pump casing will crack again if the piping configuration is not properly modified.

 

[rww88]

Take a look at course number M225 at PDHcenter.com