the spectrum of motor show high amplitude 1

[thebeginervibration]

e.motor 1465 rpm drive by t-belt overhung axial variable fan 291 rpm with 6 blades in the motor inboard and out board spectrum i see 0.2x and it is harmonic which reach 16 mm/sec rms (0.2*1465)=293 the high reading was at m1h.m1v.m2h.m2v.m2a i confused in the reason of this high vibration is the belt is the reason or eccentric pulley or the balde mechanism ? plz help

 

[Strong]

(0.2*1465)=293 That's petty close to fan speed at 291 rpm, isn't it? If yes, then I would consider fan rotor unbalance as first possible fault.

Walt

 

[Tmoose]

Is the 1X fan vibration really 16 mm/sec on all 5 motor measurement positions?

Could you post a picture of the installation? I am wondering if this is an axial fan mounted in a round duct with the motor bolted to a two dimensional motor mount that in turn is just barely stuck to the duct, like this -

http://i21.geccdn.net/site/images/n-picgroup/75205.jpg

How high is the 293 cpm vibration on the fan bearings?
And, on the duct, if it is a duct mounted blower as shown above.

 

[thebeginervibration]

internal inspection was carried out on variable pitch axial flow fan and i found that two links of haydrulic mechansim which moves the pitch of the fan blades were found broken and that is the cause of lossenes and unblanace problem which appear in the motor spectrum
and thanks storng.

dear Tmoose i say that i see 0.2x and it is harmonic which reach 16 mm/sec rms (i mean that one of 0.2x harmonic reach 16mm/sec in the spectrum of the motor not the 1x of the motor )
and this is a graph of the installation

 

[DLite30]

Proper and accepted terminology is critical to good communication. Practice it.