I have portable unit for measuring vibration speed (rms mm/s), acceleration (gPk) and gSE.

I have manufacture chart for implementation of gSE for monitoring bearing and I am not confident with it. I know it is possible to monitor rolling bearing condition with acceleration (gPk or mm/s2).

When I want to convert gPk to mm/s2 I do it gPk*9,81=mm/s2 is this correct?

When monitoring rolling bearing by acceleration what are recommended values for good/bed/in the middle bearing?

What is better technology gSE or acceleration?

Enrique,

gPK=9.8 m/s^2 PK =9800 mm/s^2 Pk

this vib convertion calculator might come handy:
http://www.wilcoxon.com/calculator/wilcoxoncalc.zip

The answer to the other questions: It depends.

IMO if you can collect gSE and acceleration readings, do it. Also, add time waveform to the list in acceleration units of course, if you can. The more tools you use, the better chance you'll have to catch a bad bearing.

I have another data collector that measure acceleration in mm/s2 and when I measure on bearing it show 21 mm/s2 and when I measure with another device in gPk the reading is 2,2 gPk.

This is the reason why I am telling mm/s2=gPk*9.81 mm/s2 in acceleration conversion.

Does anyone has recommendation levels in acceleration to estimate the condition of a bearing?

Eq

[QUOTE]Originally posted by Enrique BL:
I have another data collector that measure acceleration in mm/s2 and when I measure on bearing it show 21 mm/s2 and when I measure with another device in gPk the reading is 2,2 gPk.

This is the reason why I am telling mm/s2=gPk*9.81 mm/s2 in acceleration conversion.

Does anyone has recommendation levels in acceleration to estimate the condition of a bearing?

Eq[/Q]
Enrique,
I think , accelaration is more of a parameter for trending rather than any absolute value of vibration. gSE is better since it gives the same values but in a frequency range above 20 KHz which bearings normally generate when problem is incipient stage. Timewaveform or demodulation may further be used for confirmation.

gSE is very susceptible to minor changes in measurement position, mounting method, accelerometer model, and a bunch other stuff. This makes the repeatability of gSE measurements from one survey to another and the trending difficult.

Additionally, the severity chart from the manufacturer should only be used for the accelerometer model there stated.

gSE (spike energy) is a great tool, but should be used along with all the others you may have at hand, since like anything it is not perfect

Any severity info about acceleration on bearing control and monitoring?

Enrique,

Refer to the following thread

http://maintenanceforums.com/eve/forums/a/tpc/f/3751089011/m/3751074441/p/1