troubleshooting a vertical multi-stage pump
troubleshooting a vertical multi-stage pump
(OP)
We have a 4 stage vertical pump which suddenly has a lower output pressure and flow. The motor amps has also dropped by 10% or 20%. Marking the pressure and flow on the pump curve, it would appear that the pump curve has dropped by about 1/4. Is it possible that 1 impeller lost its key so only 3 of the 4 stages is rotating?





RE: troubleshooting a vertical multi-stage pump
Mike Cool
Mechanical Engineer
American Stainless Pumps, Inc.
Los Angeles California USA
www.aspumps.com
RE: troubleshooting a vertical multi-stage pump
If it's a synchronous motor (more than likely) how can it slow?
OP
Yes you could have an impeller problem.
But, you could have a restricted inlet - less flow, head and power. Look further before pulling the pump.
RE: troubleshooting a vertical multi-stage pump
Mike Cool
Mechanical Engineer
American Stainless Pumps, Inc.
Los Angeles California USA
www.aspumps.com
RE: troubleshooting a vertical multi-stage pump
RE: troubleshooting a vertical multi-stage pump
RE: troubleshooting a vertical multi-stage pump
Mike Cool
Mechanical Engineer
American Stainless Pumps, Inc.
Los Angeles California USA
www.aspumps.com
RE: troubleshooting a vertical multi-stage pump
RE: troubleshooting a vertical multi-stage pump
Speed of the motor
Impeller loose
Impeller plugged
Wear rings worn
Strainer clogged
Suction valve throttled
RE: troubleshooting a vertical multi-stage pump
Johnny Pellin