Piping out of roundness 1

[John Jones]

Does anybody have practical experience on out of roundness of piping assessments? A damaged/ dented stainless pipe is causing some issues. The design code is ASME B31.3

 

[MJCronin]

This might help....

https://www.eng-tips.com/viewthread.cfm?qid=154956

https://www.piping-world.com/pipe-fabrication-tolerances

https://blog.morganitech.com/pipe-misalignment-hi-lo-in-pipe-welding

MJCronin
Sr. Process Engineer

 

[0707]

Your material specification can help,


meanwile go to:

https://tpmcsteel.com/note-5-tolerances-of-steel-pipe/

https://pipelineoperators.org/cdn/2...tions and requirements for ILI - Nov 2021.pdf

 

[SJones]

Uninstalled pipe, or in service?

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/in/drstevejones

All answers are personal opinions only and are in no way connected with any employer.

 

[John Jones]

Installed and messing up commisioning with disagreements.

 

[LittleInch]

Definition of dent or damage is notoriously difficult.

Dimensions of the damage or photo would help, but this is often subjective and depends how hard it is to replace or repair.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[John Jones]

Hi Little Inch,

Photos not possible, offical photos ect. It's a lenght of stainless with a sharp impact.

I was thinking of a form of damage replication. Get a similar spool and dent it in the same manner. Then hydrotest it, PT and X ray it.

 

[r6155]

A sharp impact is not a out of roundness.
Replace damaged pipe.

Regards

 

[MJCronin]

Agree with R6155 .... There is always a problem with understanding the problem when there is a difference in english definitions across cultures.... A dent is not an out-of-roundness ...

When the OP refuses to provide pictures or co-operate in any meaningful way, it slows or stops the problem resolution..

Lets try these:

https://www.eng-tips.com/viewthread.cfm?qid=260445

https://www.eng-tips.com/viewthread.cfm?qid=367451

MJCronin
Sr. Process Engineer

 

[brimmer]

Repair or replace. Not sure what service this is in, but even if you inspect it now and find no anomalies in it, some can develop over time (again, depending on service conditions). Numerous acceptance criteria exist in the pipeline integrity world for dents (size in terms on depth diameter, sharpness, strain level, etc., ASME, CSA, BS, etc.), and fatigue based assessment methods. I would simply replace if it s sharp dent, these are generally the worst as far as strain level and they develop cracking over time. If the job called for new (undented) pipe, I don;t understand why you wouldn't replace it. If not, complete a strain analysis and fatigue analysis based on expected service.

 

[1503-44]

Analyze all you want, dont change the facts. A sharp impact damage should generally be replaced by a full diameter cut out.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."