It was high everywhere - and loud.
Probably had the wrong design (probably should have had a multi-stage) but the Project Group who installed it opted for the cheaper version. This "fix" was also the cheaper of the possible solutions. You get what you pay for (hopefully) and our fix was...
1) Lower capacity impeller (smaller diameter). Sized for better performance where the operation spends the majority of the time while compromising slightly on the high end of the previously specified flow range. (Operations still operates at the same flows that they used to.)
2) Changed to a...
Sorry about the delay.
Yes. 1 of the 8 pumps now has a new impeller - they want us to pay for the other 7. The new impeller is designed for a BEP at a slightly lower flow - but still sufficient for operational requirements. The fix was not perfect, but a significant improvement.
My...
teowl,
I remember a similar issue I had, but first a comment.
"Long Standing" issue - does this mean that it was there from original installation, or has it developed/worsened over time. I will assume it was there from the beginning, but if not, then an inspection/repair report (of the vane...
Mike,
Taylor Forge "Modern Flange Design" Bulletin 502 contains the following:
"When the condition is encountered where a very few bolts will satisfy the requirements of safety but will result in bolt spacing so wide that leakage may occur, it is necessary to adjust the design either by...
Thanks Paul -
Maybe question needs a little clarification for others -
This is a semi-circle component with OD, ID, and splitline bolts.
No sealant or gasket between component and the case it is fastened to.
ASME VIII MA 3, Art 3-3 Flanges with Ring Type Gaskets discusses required bolting...
I have looked through the ASME B&PV for this, but no luck.
I have a capscrewed metal-metal joint that has an outer diameter and inner diameter bolt circle with pressure applied between bc.
I am looking for a reference that relates the applied pressure, flange thickness and material, bolt...
Does anyone know a Field Service Company that is capable of testing Generator electrical components - CTs PTs Wattmeters, etc - on site?
Did some basic Google searches - surprisingly not very fruitful...
"sms" mentioned SohreTurbo.com. They sell the equipment that you would need to remedy those types of situations - but that being said, they have reviewed numerous similar situations and can provide an opinion (and potentially an "official" report if requested). Keep in mind that they are...
Thank you - Since posting the question, I have read the Sohre and found a few others, including one from Alexander Leyzerovich:
http://pepei.pennnet.com/Articles/Article_Display.cfm?Article_ID=44279&pc=gls
(not sure how to make it a link)
I suppose the most important aspect is that the shaft...
I've seen electrical discharges cause problems in ball/roller bearings, and I've seen damaged turbine babbitt bearings from electrical discharge, and I understand how this can happen.
Is magnetism any way associated with this phenomena?
What is the failure mode when the bearing housing is...
Not a repaired shaft. Just a straight 4140 journal. I like your "devil's advocate" thought, since I originally ruled out the possibility of something getting into the bearing clearance since I was sure there would be subsequent babbitt damage. Then Steve helped me think that the particle...
The shaft is normal 4140. I'll be sure to let you know if I find anything in the babbitt upon closer inspection....
Have you ever seen something larger than bearing clearance get stuck in the pressure dam area and slowly polish the shaft?
http://www.bearings.machinedesign.com/guiEdits/Content/BDE_6_1/bdemech6_21.aspx
No appreciable babbitt damage in my case. I'm tending to think this may be a very minor case of wire wooling which occurs at startup when film thickness is not yet established.
Thanks again for your help, and the...
Thanks.
Looking at the sleeves, the grooves almost look polished. My initial thought was that something larger than the bearing clearance made it into the pressure dam area and slowly wore away at the shaft over time - therefore, no shaft cutting or raised edges to break down the babbitt. I...
