Dislocated Pipe

[marchieV]

Hello.

What is the formula to get the surge force in a pipeline with expansion loop? I need to check using the CAESAR II program the reasons and probable solution on why the pipeline clashes on the adjacent pipeline.

Thank you.

 

[pennpiper]

marchieV,
You wrote:
"I need to check (using the CAESAR II program) the reasons and probable solution on why the pipeline clashes on the adjacent pipeline."
CAESAR II might help some but common sense and the experience of a well trained Piping Designer will solve your problems.

It sounds like you do not have:
(a) the correct "Pipe Anchors & Guides" to control the movement of the Loop -
Are you using Pipe Anchors and Pipe Guides on your Hot Lines?
If not, Why Not?
and
(b) the correct spacing of the individual pipe lines -
Recheck the spacing of all your Hot Lines, Increase the spacing to compensate for the bowing and creep of the hot lines.
"Can't and "No Space" are not the correct answers.

Sometimes its possible to do all the right things and still get bad results

 

[KevinNZ]

What do you mean by surge force?
What is the fluid?
Does the pipe jump over and hit the adjacent pipe under some dynamic loading?

We have problems with slugs of water in two phase lines. As general rule we say there needs to be an anchor or line stop in every run between elbows.

 

[bimr]

Pipeline hydraulic transients occur with changes in flow and these hydraulic transients are generally due to:
1) Pump start and stop, especially due to power failure
2) Valve operation (closure/opening)
3) Check valve closure
4) Air pockets in pipelines, especially at pump start
5) Air release
6) Pipeline filling

A picture of what you are referring to would be helpful.

 

[marchieV]

Actually the pipeline that I am talking about is already operational and has been designed BUT I do not know if they consider the surge analysis of it. Based on my understanding the cause of the clashing is due to the transient pressure/ surge pressure of the fluid inside because according to the operators of the plant every time they shut-off the valve they notice a drastic movement on the pipe especially near the expansion loop. I need to investigate and justify such speculation considering that the original designer of it did not analyze the system for surge analysis.

The client wants to know the reason for clashing and they need a recommendation in order to avoid such problem.

 

[bimr]

One solution is to modify the shut-off valve so that it operates slower and eliminates the transient.