Fabricated Union

[D123456]

I am trying to establish that a fabricated pipe union threads are suitable for the service.
M36 x 2.0
Length of threads is 10.5mm.
Material is SA-105 for male threads, SA-240-316 for nut.
Union is for a 3/4" pipe.
363psi @ 482F

I have calculated thickness required of the weld ends (thinnest portion) but need to ensure the threads can handle the load.

The issue I have is trying to establish what area of threads I require.
Any help or resources would be greatly appreciated!

 

[D123456]

Maybe I don't need to show thread strength if union conforms to Fig. 335.3.3 - where sealing is at a surface other than the threads?

 

[mk3223]

To save time for making it by yourself, try B16.11 for pressure rating and the thread fittings detail, and ASME B1.20 for pipe thread detail.