FFS Dent in Stainless Spool

[John Jones]

Hi guys,

I have an SS sch10 24" that has reached commisioning stage. There is a dent in a section of pipe which is causing issues.

Does anyone have experience in fitness for service analysis of such situations?

It would be extremely troublesome for all involved if this spool had to be removed.

 

[LittleInch]

Same question as this post?

https://www.eng-tips.com/viewthread.cfm?qid=507922

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

 

[TugboatEng]

Aside from the pressure rating, dents in piping can also cause turbulence which can lead to erosion downstream of the dent. Stainless steel isn't particularly sensitive to this damage but it is something to consider.

 

[1503-44]

PLEASE DELETE THIS THREAD.

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

 

[LittleInch]

A few options:

Accept the dent if the system is operating at low stress, say <20% SMYS. Monitor for cracking on a monthly basis for ever.

Cut out and replace.

Repair with full encirclement welded sleeve or external sleeve like clockspring.

Some idea of how big this debt is would help a LOT.

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

 

[brimmer]

API 1183, ASME B318 App R, to name a couple... there are many. These are related to gas/oil transmission pipelines, but the same principles apply for other pipelines. No idea of your service, so I can't comment on consideration of other factors you may want to consider