API 681 Pumps - Dynamic loads

[Janimi]

Hey guys,

we often get the question from customer side if we have dynamic loads coming out of the pump to the foundation.
Normally we say the dynamic loads are negligible in contrast to the static weight load because it is a liquid ring machine and not a reciprocating machine. Even the process loads are very small.
How do you handle this stuff? I could imagine to give maybe the force coming out of an unbalanced rotor but does this have so much effect? I don't think so.

Best regards

 

[Rputvin]

Our impellers are dynamically balanced, similar to balancing a tire/wheel on a car, during either production for pre-trim and full size impellers, or when being trimmed for the rest. The weight for balance is removed via machining on the face of the impeller. I'd assume the same is true for most any pump manufacturer.

I don't think we've ever been asked about any loads coming from the rotating elements. We've done some rubber isolators on motors that tend to vibrate, refrigeration compressors can get some movement going on, or if the customer is extra-sensitive toward vibration.