Flanges calculation following ASME Code App2 1

[PeterWay]

I'm designing flanges under Asme Code with a soft for a pressure vessel.

The program gives me a warning concerning the flanges rigidity, the expresions (and results) are:
JO = (109,4 |MO|)/(EO t^3 ln(K) KL) = 0,181 shall be < 1,0
JA = (109,4 |MA|)/(EA t^3 ln(K) KL) = 1,29 shall be < 1,0

In this case JA doesn't fits the requirement. But if I take a look to the stresses they are under the 30% of allowable stresses.

Is the requirement of flange rigidity mandatory or it could be omitted considering the existing stresses?

My question comes because in calculations played before for similar equipments with other soft flage rigidity is not taked into account.

Thanks a lot!

 

[SnTMan]

PeterWay, flange rigidity was made mandatory in the recent(?) past, for older designs it was non-mandatory.

If you are required to design to current Ed / Add you will need to meet it.

Question: Soft what?

Regards,

Mike

 

[PeterWay]

Thnks SnTMan.
We're using Microprotol and it indicates that the flange rigidity is not accomplished.
I saw some third parts calculations made in PVElite for similar equipments and the flange rigidity was not calculated. As they are ancient calculations, I assume what you said: at that moment the flange rigidity was not required.