Calculation of Unknown Bearing Types in your Equipment
Knowing the exact bearing information for your equipment can make bearing defect analysis much easier. However, it may not always be possible to acquire the bearing information for your equipment. This can make it difficult to determine the bearing fault frequencies for correct analysis.
It is possible to remember easy formulas to calculate the approximate bearing fault frequencies for rolling element bearings. The following formulas are easy to remember and can help you when the bearing information is not known:
FTF = 0.43 × RPM
BPFO = 0.43 × N × RPM
BPFI = 0.57 × N × RPM
Where:
FTF = Fundamental Train Frequency
RPM = Revolutions per minute
BPFO = Bearing Pass Frequency Outer Race
N = The number of rollers
BPFI = Bearing Pass Frequency Inner Race
The values derived from these formulas should be within 10% - 15% percent of the actual bearing fault frequencies.
Other formulas are available that will more accurately estimate bearing fault frequencies than the ones listed above. LUDECA will be happy to provide those to you upon request. Email us at info@ludeca.com.
Tip provided by LUDECA, Inc.
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Comments (2)
i thank to you to providing this type knowladge.
i wannt to learn about vibrationcalculation,powercalculation of any system they attache with the motor.
1) Posted 6:03 am, 09 November 2011 by hemant
how is analysis fault frequency?
how is use formula?
2) Posted 12:47 pm, 14 November 2011 by arunachalamnallaperumal