On the basis of the structure and installation characteristics of vertical pump unit

the reason why structure resonance fault frequently occurs in site was analyzed

and the solution measures were put forward.The vibration mode diagram method was recommended to identify the structure resonance source.Then

according to the actual situation

several measures can be taken to alleviate or eliminate the structure resonance

such as adding supports

adjusting the contacting area and level

field dynamic balance and others.Finally

this solving method was applied on two condensate pumps and the vibration reduced to normal level

indicating this method is effective.