Re: Regarding Piping Stress Analysis

From: <Christopher>
Date: Sat Feb 26 2005 - 11:25:00 EST

On Feb 26, 2005, at 2:13 AM, sathish babu wrote:

> So i have designed my Piping system in such a way that,the forces and
> moments transmitted to the valve inlet and outlet ( BW ) is less than
> the value specified by the valve manufacturer.
Right on. Usually valve bodies are thicker and stiffer than pipe wall, so you won't run into problems, but you sometimes run into situations where the guts of a valve bind up or the valve won't shut off if the piping loads are too high. Pretty soon you have some guy putting a pipe wrench on the valve to operate it and the valve 'just broke.'

I've worked both sides of that counter. I spent months trying to explain to a to various project coordinators and expeditors and what-have-you why a sheet metal air-to-air heat exchanger should not be assumed as a rigid support, as the manufacturer of the heat exchanger had warned before the heat exchanger was sold. It turned into another mind-reading exercise until I finally was permitted to make contact with the piping guy and we figured out what was going on.

Christopher Wright P.E. |"They couldn't hit an elephant at <a href="/group/PipingDesign/post?postID=nZY5F4G9dkjd75m8YY-SRURyc6uhtkArjtOy7irHql4j1V8Axq_u3vEj7LHw9Fc2oWbxCJyJWRFlwISzoUU">chrisw@skypoint.com</a> | this distance" (last words of Gen.

.......................................| John Sedgwick, Spotsylvania

1864)
<a href="http://www.skypoint.com/~chrisw/">http://www.skypoint.com/~chrisw/</a> Received on Sat Feb 26 11:25:00 2005