Membrane stress calculation

[eagnaday]

Hi,
I have a question about Pm calculation.
how can we calculate membrane stress (Pm) acc. to ASME Sec VIII Div.2?
Is Pm same with actual stress Sa?

 

[Jay_]

My replys to you are the below?
1) Are you designing a pressure vessel or performing a fatigue analysis?
2) if you are performing fatigue analysis then we only care usually about the nozzle/shell junction really.
3) you might wanna look at mosses handbook for the primary stress around shell openings. Its somewhat conservative.
4) i usually do FEM to linearize the stresses. It’s not a straight forward path to do it, trust me.
5) read studies about linearizing stresses.
6) understand thoroughly all the types of stresses in division 2 like primary secondary and peak as well as bending stresses.
7) hire a Proffessional at this moment to do this task because trust me not a single soul can help you right now without fully understanding the project.
8) good luck.

Detailing is a hobby,

 

[cbPVme]

This is a very rudimentary question. Honestly, if you need to ask this, you need to hire someone familiar with ASME Section VIII Division 2.

 

[DriveMeNuts]

The definition of membrane and bending stress should be known before opening any pressure vessel code.

Section 5.12 of Div 2 does provide a definition which may help you.