trunion support dia calculation

[xnabrar]

Hi All,
shear with me what will the dia inch I can use for the trunion support if my NPS is 16'' any calculation?

 

[KevinNZ]

You may need to use FEA to find the SIF and use this in the piping stress analysis.

 

[MJCronin]

"Shear with you" ?????

My general suggestions, based on many years of dealing with trunnion supports is:

1) Trunnion diameter shall be piping not less than 1/2 of the parent pipe diameter

2) Trunnion diameter shall not be the same size as the parent pipe diameter
(Very difficult to fabricate and the larger diameter is usually unnecessary)

Therefore, I would consider: 8 inch NPS, 10 inch NPS and 12 inch NPS all as possible candidates ... Depending, of course on calculation

Do you see where it says that " Trunnion size shall normally be one size down as parent pipe and shall be verified by calculation" ?

You are the pipe support designer ... what were the results of the calculation you performed ?

What is both the material and the pipe schedule of the parent pipe ?

You are not trying to put a trunnion on that shitty Schedule 10/10S piping are you ????!!!!?????/

MJCronin
Sr. Process Engineer

 

[AskTooMuch]

Our plant specs call for I beam for trunion if I remember right. Don't the specs with me right now. Trunion made of pipe is not ok because of inspection/ndt test issues.

 

[saplanti]

Normally this trunnion diameter is to be determined in the pipe stress analysis with the drawing guidance. And, a support stress calculation follows (there are spreadsheet calculation and FEA reports on trunnion by companies).
Pipe support designer follows the pipe stress report for the issue if this procedure is the same internationally.

 

[MJCronin]

xnabrar...

Trunions and different methods of analysis have been around for a long time

There is a large amount of information on the design of both "pipe support trunions" and "lifting trunions" (for placement of vessels) on this forum as well as on the internet.

Some of that information is here:

https://www.eng-tips.com/viewthread.cfm?qid=220232

https://www.eng-tips.com/viewthread.cfm?qid=428126

https://www.eng-tips.com/viewthread.cfm?qid=144736

https://www.eng-tips.com/viewthread.cfm?qid=461823

https://www.eng-tips.com/viewthread.cfm?qid=257454

https://www.eng-tips.com/viewthread.cfm?qid=25754

https://www.eng-tips.com/viewthread.cfm?qid=408033

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http://www.mps-gradior.cz/uploads/download/id22/kat EN.pdf

(page 4 5.4 and 5.5)

https://www.lisega.de/wp-content/uploads/2016/06/EN-LISEGA-Catalog-2020.pdf

https://www.bindergrp.com/wp-content/uploads/2014/03/BINDER-CATALOGUE-2015-COMPLETE-WEB-Rev-1.pdf

https://www.scribd.com/document/82014946/Trunnion-Stress-Validation

https://www.scribd.com/document/350182724/Master-Trunnion-Calc

https://www.scribd.com/document/396686228/BASF-Engineered-Pipe-Support-Catalogue

MJCronin
Sr. Process Engineer

 

[xnabrar]

thanks for all your information helpful for me.
parent pipe diameter 16'' w.t 0.344 and material is API 5L GR x 60.