Allowable Limit of Vibration

[ashfaqanwer]

Can anybody state the allowable limit of vibration on pumps according to API?

[fraz]

Maximum allowable vibration according to API for horizontal pumps is 3.0 mm / sec RMS ( for pumps having max. rpm = 3600 and max. power absorbed = 300KW), while for vertically suspended pumps this limit is 5.0 mm / sec RMS. Plesae note that 30% increase in these vibration limits are allowable for pumps running at flows outside the preffered operating region but within the allowable opearting region.

[sakib321]

will you please quote reference of API ?

and what about the acceptable limits of G's?

[fraz]

1. These limits are according to API 610
2. Acceptable limits in G's are not given in API 610, but 3.0-4.0 G's are normal values for pumps having antifriction ( ball / roller) bearings with speed of 3000 rpm. Above this will indicate the problem in bearings or cavitation.