Regarding to Flange checking module (shown as window menu: Analysis>Flange), manual says:"Flanges attempts to improve upon the solution of this difficult analysis problem. Equations model
the flexibility of the annular flange plate and its ability to rotate under moment, axial force....."

I want to know more details about improvements compared with rules of ASME VIII DIV.1 , especially on stress calculation and leakage evaluation.
Any instruction is highly appreciated.

Regards

Gino Zhang