ASME B16.9 Para 2.1

[dursosono]

Refer to ASME B16.9 Paragraph 2.1, state "The allowable pressure
rating for fitting designed in accordance with this Standard may be
calculated as straight seamless pipes of….".

It's mean if we using pipe cap (under ASME B16.9) for head of pressure
vessel, we may to calculated thickness requirement based on shell
only?

 

[DSB123]

dursosono,
B16.9 covers pipe fittings. As such the fittings are able to withstand the same pressure as straight pipe of a similar thickness. So if you determine what thickness of straight pipe you need for your situation then if you select a comparable material(for the fitting)to the pipe then you do not need to perform pressure thickness calcs if you select the same pipe schedule as the straight pipe selected.

 

[eliebl]

If you are building to ASME VIII-1 then see UG-44 with respect to the use of standard pipe fittings.

EJL