I ran a flange leakage calculation using the Caesar II flange analysis. The ANSI B16.5 equivalent pressure calculation has a safety factor of .93 and the Flexibility/Gasket Compression Model has a safety factor of 35. I would appreciate some expert opinions/advise on why there is such a big difference and the accuracy of the two models.

ANSI B16.5 has nothing to do with flange leakage. The MAWP listed is based on the elastic modulus of the flange material and does not consider bolting or gasket parameters. This value is included in the CAESAR II output only because many people want to see it.

Additional discussions on flange leakage can be found in this forum (using the Search option above. The following is a summary of the search results:


Flange Leakage

Flange Leakage Criteria

Caesar II\'s Flange Calculator

Flange Allowable Stress Multiplier

effective gasket modulus

Flange leakage

Flange leakage is a phenomenon that has not been resolved from an engineering computation point of view. Various (code) committees are still working on this issue, but there are no new published rules to date. The CAESAR II method for flange leakage is discussed in one of our newsletters, October 1991. If you don't have a hard copy, you can find this issue on this web site at: http://www.coade.com/newsletters/oct91.pdf

CAN ANYONE GUIDE ME ABOUT PIPING STRESS ENGINEER REQUIREMENT IN US , i am a piping stress engineer with 5 years of experience