RCM-2009 Reliability Centered Maintenance Managers' Forum - March 23-26 - Daytona Hilton Ocean Walk Village - Daytona Beach Florida Join or Manage Your Profile Posting Boards Machinery Condition Monitoring and Predictive Maintenance Posts About vibration/alignment/balance Shaft Runout Tolerances
Join or Manage Your Profile Posting Boards Machinery Condition Monitoring and Predictive Maintenance Posts About vibration/alignment/balance Shaft Runout Tolerances|
Go
|
New
|
Find
|
Notify
|
Tools
|
Reply
|
|
I was wondering if anyone here may have a link to where I can find a spread sheet, or tables, on shaft run out tolerances. This would be for mostly over hung fan shafts, up to 5 inches in diameter...I have one here I need to check on.
Thanks R. Bell Baton Rouge, LA |
|||
|
Hey Rockin'
Sure. I'll send it to you. It's right in my binder with my other critical charts........... 'At what level of vibration will my machine fail?' 'Calculating the correct balance trial weight without knowing the rotor mass or speed' 'Determining shaft material by taste and smell' OK, let's get serious. If the shaft is bent near a fan, then you can calculate, at that runout, how much unbalance is due to that and if you then think it is safe to hang that much weight without tearing the fan apart. If the shaft is bent near a coupling, that information can be used in your alignment tolerance number. If the shaft is bent near a sheave, remember that the wonder manufacturers of sheaves have given themselved one huge loophole here. A sheave can have up to 0.001" runout for every inch of sheave diameter! Imagine a 10 inch shaft with 0.010" runout under the belt. Would you operate a machine with a 0.010" inch bent shaft? Oh, that's right, you are asking that question in the first place!!!  I believe that Reliance spec for all motor shafting material was no more than a maximum of 0.002" runout for 1800 rpm and lower and no more than 0.001" for 3600 rpm. Have a good one! Sorry for bustin' em. |
||||
|
Basically field tolerance for runout is 2 mils with a stack tolerance of 3 for general purpose machine and a bow in the middle depends on length of span, material and physical characteristics of shaft, drive shaft or torque tube.
First member = shaft; 2nd = hub & generally 3rd member is not a member that is an intergal part of the shaft and may float. On high speed, precision machines those numbers drop. Use OEM specs as guidlines and/or consult ISO standards or acceptable engineering practices. Cordially, Sam Pickens pdmsampickens@gmail.com |
||||
|
Ron,
You killing me, har-har-har....Anyway to get down to it, I called the machine shop yesterday after I posted my question. These people do alot of our pump repairs and shaft machine works. He told me their standard is .0005 for every foot of shaft, regardless of the diameter. So the fan I'm talking about has a shaft of about 4 feet in length, which would make my max limit .002 I checked it at .004. Probably not a real huge factor, but my question was one mostly of curiosity. I looked all over the net yesterday for those guidelines, never could find anything on it specifically. Thanks,
R. Bell Baton Rouge, LA |
||||
|
The API standards for the new equipment specify max TIR of 0.001" or 0.0015" depending on shaft flexibility(L4/D3). For the vertical pumps the TIR should be 0.0005"/ft of length or 0.003" max.
As a rule of thumb for overhauled equipment keeping TIR below 0.001" (3600 RPM) and 0.002" (1800 RPM) should be maintained. |
||||
|
Those shaft specs were for overhung fan shafts. I believe the specs vary for different applications. we don't too much worry about the pump shafts here until we tear one down for overhaul.
Alex better get prepared for Gustov. This thing doesn't know where it wants to go. Looks like us so far, but is veering west a tad, probably change again this weekend... R. Bell Baton Rouge, LA |
||||
|
I vote that he veers to the East. Not that I have anything against Lousiana or Mississippi... just selfish. But I don't think Gustav really cares about my opinion.
Did you see the latest projections on Hanna. Instead of veering clockwise up into the east coast, she's now projected to veer counter-clockwise towards the Gulf. Two more areas of interest farther east in the Atlantic. |
||||
|
What part of the coast you at? We'll send some your way, hehhe...
R. Bell Baton Rouge, LA |
||||
|
| Previous Topic | Next Topic | powered by eve community |
 | Please Wait. Your request is being processed... |
|
|||
| Site | Join or Manage Your Profile | ||
| Servlet | eve1da019 | ||
| Version | 1.3.0 build 9383 | ||
| Module | Forums 4.0.3 | ||
| Stylesheet | "Eve" | ||
| Wordlet Set | "Default Wordlet Set" | ||
|
Contact Us | RCM-2009 Reliability Centered Maintenance Managers' Forum - March 23-26 - Daytona Hilton Ocean Walk Village - Daytona Beach Florida | Privacy Statement | Terms of Service
Copyright © 2004-2008 NetexpressUSA Inc. All rights reserved.