Non standard flange design

[SSP1987]

How do I go about designing a non standard flange as shown in the picture? Any tips?

 

[SSP1987]

Picture 2

 

[SSP1987]

Picture 3

 

[mk3223]

What does the overall picture of the equipment look like for the “flange” joint to the “shell”?
Why not to use the standard flange joint?

 

[LittleInch]

For those who won't download.

But I cant work this out at all.

FEA?
ASME VIII Appendix A?

Looks unlike any flange I've ever seen.
Well you've drawn it so that the first part. what do you need to do next?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Cobra17]

If there is metal to metal contact outside the bolt circle it would be an appendix Y flange. You might have to fudge the gasket location in most of the commercial software since it's located on the 'inside' of the flange hub