Fan vibration

[kafman]

Hi guys.
I got that a fan bearing with high vibration on its bearing and its foundation.the shaft alignment, bearing radial clearance and v-belt tension was inspected but still the vibration didn't reduced..>12mm/s.
The fan is fan for small bag filter in cement plant

 

[dvd]

Did you speed the fan up? There appears to be a speed increase ratio on sheave diameters.
Is the fan on a VFD - what happens if you run at different frequency?

 

[3DDave]

I would have expected the first step was to clean the fan and see that it is balanced. Belt tension is if there is belt squeal on startup.

 

[kafman]

Did you speed the fan up? There appears to be a speed increase ratio on sheave diameters.
Is the fan on a VFD - what happens if you run at different frequency?

Appreciate ur idea..the fan is not on VFD,,but what will has a tendency to creat high foundation vibration

 

[Stick.]

Do you have any info on the frequency of the vibrations in relation to the motor and fan speed?

 

[kafman]

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Do you have any info on the frequency of the vibrations in relation to the motor and fan speed?

Based on standard,,vibration of the fan must not exceed 1.8mm/s,,but now vibration developed >15mm/s

 

[dtimberlake]

Without vibration frequency, phase and direction information I feel I'm bringing a knife to a gun fight.
Well, actually more like bringing a Nerf gun to a gun fight. Basically I'm un-armed.

1X fan speed
- unbalance
- looking at that wimpy set-up, fan pulley/sheave runout ( unavoidable with v-belt pulleys ) .

1X motor speed
- unbalance
- motor sheave runout. especially horizontal in the direction of belt pull

Some harmonic of belt "rotating" speed
-uneven belt thickness - especially horizontal in the direction of belt pull - "wrapped" belts are much worse than belts with cut sides in this regard

 

[MintJulep]

Big globs of cement and grease on the fan wheel seem a reasonable thing to check for.