Can anybody tell me why Phase is not measured on routine machines like pumps, recips, fans etc

Doesn't it help in diagnosis of them as well like big machines?

yahoo,

You would have to have a piece of tape on all equipment, and then, unless you are using the Enpac 2500, you would have to carry a tach or similiar apparatus to capture phase. It would add a lot of time to a route to do so.
Easier to get data, see which ones need further analysis (such as phase) and then just deal with the anomalies.
The Enpac 2500 has a built in lase tach byt the way, which I think is the only one that does, although SKF's hand size collector may. They bought the outfit that makes most all of the collectors now. If there were no markings on the boxes, you couldn't tell the difference between Entek's line of Enpacs and SKF's line of whatever they call theirs

Dave

PdM or route management does differ from vibration analyses. Vibration analyses takes longer so it is advantageous to filter down to those few. And in the process, most will be obvious, fewer requiring additional analysis.

By sure numbers; most machines are 2 pole or 4 pole with A-F bearings where the general machine in a plant, where alignment and setups aren't a serious problem - you'll find the first thing to go is the A-F bearing. Most of these machine will run until bearing failure and by that token acceleration will detect the fault and predict time without the aid of phase data.

When PdM has flagged a problem and it isn't clear as to fault; then addition analyses may be required along with RCA. Then you can use an array of tools; phase, nyquist?, bode?, TWF, Windowing over various basebands, etc... In-depth analyses isn't justibible on all machines. Or so I think. However, if you have a small program and a lot of time - go for it.

On a routine route when spectral and TWF data are taken by one person and if the route is long, the time consumed by the phase collection would make it almost impossible to complete a route, of say 600 points, in a reasonable amount of time. If phase collection is needed, this could be setup on a different route at a different time, hopefully within the same day.
I would say TIME is the reason for not collecting the phase along with the normal routine route, if that is what you are asking.


Only my opinion and I could be totally wrong.