I must to diagnostic about a problem that I didnīt see before now. Itīs an electric motor directly coupled with a pump (horizontal position). All vibration is low, except in the motor, side to coupling. Characteristics of the motor: Weg 160L - Maximum 30 HP - 3525 RPM - SKF Bearing 6309 side to coupling - Electric frequency 60 Hz - Triphasic Characteristics of the pump: Qty: 6 pump vanes - 7 1/2" impeller diameter - Light slurry FFT Display: Maximum 120 kcpm 400 lines 2 samples Only one peak of 11,8 mm/sec at 300 cpm
If you used the bearing defect frequency calculator for SKF 6309 (found on SKF) you can see that this 300 Hz is near to 292 which is BPFI, but you should first increase your resolution.
if u make sure it's really BPFI take ur decition quickly as 11.8 is not good for bearing fault.
A difficult diagnostic
Posted - 01/18/2010 : 14:28:11
