Res Sirs,

I am presently engaged in the field of VA of rotating machines and bearings for a few years. I have following doubts. Please clarify them

Doubts:

1) If in the bearings, both inner race and outer race rotates , Rotating speed of shaft, inner race , outer race and number of balls are given. How to find BPFI?

2) If BPFI or BPFO in the bearing is accompanied by 1 x RPM side band what does it mean? . Could it mean the defect is wide enough to include 1 x RPM side band or bearing is loose on the shaft?

3)Suppose I have to measure 70.000 Hz frequency With 40,000 HZ Accelerometer, How amplitude sensitivity and frequency sensitivity will be affected? We know as the frequency of the accelerometer increases, size of crystal become smaller and hence amplitude sensitivity become smaller , but the problem is how the frequency accuracy is affected?

Again thanking you profusely for having clarified my doubts

K.Ravindran