John from PA posted:
Q1. What is the tooth combination?
Q2. Fluid film or rolling element bearings?
Q3. Is the casing a weldment or a casting?
Q4. What is the exact transducer being used?
Q5. I see 16 mm/sec2 as your highest level acceleration. I could have done the conversion incorrectly (I'm working from a tablet) but in making the conversion to g's I get the following. In comparison to API 613, the levels you have measured seem low.
I stand corrected, I quickly scanned the spectra for frequency and relied on the spreadsheet for amplitudes, which are only micron, mm/sec and mm/sec2
My questions Q1 through Q4 remain to be answered.
Are you certain this is a single helical? Is the ratio supposedly 10:1 exactly.