I did a comparison of flange design based on ASME Section VIII Division 1 vs Division 2 with following parameters

Design Pressure : 10.2 MPa

Design Temperature : 80 degC

Flange Size: DN400

Flange Class : Class 600

Flange Type : Weld Neck Raised Face

Gasket : Spiral Wound

Pipe Force : 17293 N

Pipe Bending Moment : 39477 N.m

The main reason for doing this exercise was that the Pressure Temperature of this flange is above what ASME B16.5 allows for a Class 600 flange.

Calculations are presented as PDF with formulas visible so it becomes easy for someone to check them against ASME Section VIII Division 1 and Division 2.

This particular flange with given Forces and Bending Moment fails gasket leakage as per ASME Section VIII Division 1 but it passes comfortably as per ASME Section VIII Division 2.

My question is, “Does the flange actually leak when given these forces and moments are applied on it?”

Calculations can be downloaded from below

ASME Section VIII Division 1 Flange Calculation ASME Section VIII Division 2 Flange Calculation