Re: Re: Vibration

From: <Jun>
Date: Fri Apr 06 2007 - 04:56:00 EDT

Waste of good money. Dampers are good if the pipe movement is due to seismic event. But if youre trying to lower thevibration on piping due to flow or attibuted to equipment dynamics (such as pumps/compressors), then the use of dampers is a waste of good money. Books by Antaki and Bloch have address issues related to piping vibration.

If you guys have never been involved with piping vibration, then check out the publication from Carmagen Report (free and can be downloaded in pdf format) written by V. Carucci- its a good intro.

Controlling Piping System Vibration - issue of Feb 2005. Screening Piping Vibration Problem - issue of Dec 2004 Common Causes of Piping Vibration - issue of Oct 2004

There are several good books on Machinery Vibration like those of Victor Wowk that pretty much explain the fundamentals of vibration measurement and analysis. Its guess work, luck and a little bit of science.

• Original Message ---- From: "Rajkumar, M. SPEL-P2" <m.rajkumar@siemens.com> To: <a href="/group/PipingDesign/post?postID=jMeXoK-9aUYoa-wP3aLszUYkblPZEGHwiFCTDtdxfEoH9rCw-DFrltHmQT323Zh8wb0-Dzq_XXlQrQd2xnMZr8h7R2Ae">PipingDesign@yahoogroups.com</a> Sent: Thursday, April 5, 2007 4:00:09 PM Subject: RE: [PipingDesign] Re: Vibration

Dear Imran,

I suppose Dampers can be used for solving this Problem

Regards,

Rajkumar M

____________ _________ _________ __

From: PipingDesign@ yahoogroups. com [mailto:PipingDesign@ yahoogroups. com] On Behalf Of jun_atibo
Sent: Thursday, April 05, 2007 12:05 PM
To: PipingDesign@ yahoogroups. com
Subject: [PipingDesign] Re: Vibration

I dont know Imran, but I doubt you could use CII to fix a problem related to piping vibration. Get a vibration analyst arm with a tool to measure velocity and frequency to figure out the mode shape and severity (before and after) - is the way i would approach this.

I would realy like to get an example of piping having a high vibration severity that was fixed using exclsuively CII.

For the newbies, my suggestion is to Check out several articles that appeared in Engineering Dynamics related to piping vibration. Or better yet the SwRI paper (no its not posted in their website but if u knew somebody who have used the services of SwRI before then get of copy of the their fine article written about piping vibration - its very good).

• In PipingDesign@ yahoogroups. com <mailto:PipingDesig n%40yahoogroups. com> , "Farhad" <farhad_ss@. ..> wrote:
  >
  > Dear Imran,
  >
  > Definitely, you should use CAESAR II software to solve this
  problem.
  > There are a few steps as follows:
  >
  > 1- Collect field data (displacements, RPM of pumps, pipe support
  > configuration, etc.)
  > 2- Model piping system in CAESAR II.
  > 3- Run static analysis.
  > 4- perform Harmonic analysis and enter harmonic displacement at
  pump-
  > pipe node.
  > 5- Tweak some dynamic parameters to model exact problem.
  > 6- Add some stiffness (pipe support) to your piping system,
  wherever
  > possible.
  > 7- Run static then dynamic analysis to see changes.
  >
  > I hope it helps you.
  >
  > Regards,
  > Farhad
  >
  > --- In PipingDesign@ yahoogroups. com
  <mailto:PipingDesig n%40yahoogroups. com> , "Imran M Ahmed" <imahmed@>
  > wrote:
  > >
  > > Hello Guys!
  > >
  > >
  > >
  > > We are facing vibration problem in the piping system of our
  plant.
  > The
  > > scenario is that the lean Amine pumps operate with a vibration
  of
  > approx
  > > 6 mm/sec pk on DE and 3.8 mm/sec pk on NDE. The vibration gets
  > > transmitted through the piping into the standby pump which is
  not
  > in
  > > operation. The vibration recorded on the standby pump is
  > approximately
  > > 3.0 mm/sec pk. Do you have suggestion how to control this
  > vibration?
  > >
  > >
  > >
  > > Regards,
  > >
  > >
  > >
  > > Imran Ahmed
  > >
  > >
  > >
  > >
  > >
  > > [Non-text portions of this message have been removed]
  > >
  >
  

[Non-text portions of this message have been removed]

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[Non-text portions of this message have been removed] Received on Fri Apr 06 04:56:00 2007