Vapor Belt Distributor in Heat Exchanger

[leon_har_dt]

Hi all!
hope you are doing good this days.
I was looking in the forum but didnt find any related thread.
I'm designing a Heat Exchanger under the ASME Sec VIII div 2. This HX has a Vapor Belt or distributor.
In point 8.1.3 says "The longitudinal stress in the shell section with openings (for flow into the shell) shall be based on the net area of the shell (the shell area less that removed by the openings) and shall not exceed the applicable allowable stress criteria." i looked the 4.11 and 4.18.8.4 and it doesn't appear this net area factor.

So how can calculate the longitudinal stress considering the net area?
I would appreciate any answer given.

L.

 

[SnTMan]

leon_har_dt, not sure what it is you don't understand.

Is it the source of the loadings? Surely you understand the idea of the net area, right?

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[leon_har_dt]

Thanks for the answer SnT
Yeah yeah, the net area its defined in the phrase I quote. Maybe i didn't make a precise question. My point was, where do i apply this net area. I review the equations related and didn't find a ecc with an area involve.

L.

 

[SnTMan]

leon_har_dt, I am not familiar with Div. 2, so I can't comment on the paragraphs cited. But anywhere a stress is computed an area is involved.

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[CuMo]

Basically what the code is telling you that you have to investigate the stresses in the shell without considering the metal which has been removed from it.
They call that the NET AREA (Whatever area is left after you drilled your nozzle holes).