Piping Stress Analysis - Coil Arrangement

[MQM90]

Hi,

I am being expected to do piping stress analysis of inlet and outlet header which is basically a coil consisting of various tubes connected to individual inlet and outlet headers.

Headers are capped at one end, i.e. closed and at the other there are typical tubes configuration like in any coil.

My questions are ;

1. On which code should i model my piping system i think it must B31.3 or B31.1.

2. The inlet / outlet header needs to be modeled or simply i start with an anchor.

3. Becasue if i dont start with an anchor then i think i must initially model a pipe of size equal to individual header (inlet/outlet), then design the tube connections (thru a reinforced/unreinforced joint configuration which ever, also anchor the main pipe / header at one end as there is cap in practical and finally model piping connected to respective headers.

4. Can anyone refer me the recommended practices/ guidelines which must be take care while carrying out such piping stress analysis for e.g. lateral movements at header to be allowed or discouraged etc.

Waiting for urgent response, please

Osama

Osama Nusrat Ali

 

[unclesyd]

What you are describing sounds very close to the outlet headers in some H2 plants. I was involved in the redesign of same but have since lost all my notes. If my memory serves me right we looked at header and pigtails under both 31.1 and 31.3 and went with the 31.1 as the pigtails are actually exposed to furnace temperature. The biggest problem we had was the MOC, as neither the pigtails or the header material were in the code at the time. The analysis was accomplished using the then brand new "Pipe Plus". The results of field measurements verified the thermal expansion given by the program. We were fortunate in that the header and pigtails were symmetrical with a center T.
This really isn't much help in your case but it was relatively easy to input the data for the analysis.

 

[BigInch]

Read the scope of each code and you should be able to determine which one applies to your design.

"I am sure it can be done. I've seen it on the internet." BigInch's favorite client.

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