FEA study with API 560 - Nastran/Analytic differences 2

[Hetairoi]

Hello,

I'm doing stress calculations using API 560 (fire heaters for general refinery services) and the thickness of my casting calculated with Nastran are largely heavier than the casting calculated with traditional methods. I can accept that this results could be caused by local singularities, but the differences are significant. So...

Does someone know if there is anyway to upgrade the desing stresses when FEA is used?

Is there any guide, reference, text, anything where API gives another procedures when FEA is used?


Thanks..

 

[TGS4]

You could try out API-579-1. Are you trying to keep the maximum stress less than your "allowable stress"? If so, then you are using the FEA tool incorrectly.

Please search this site for discussions involving ASME Section VIII, Division 2 and FEA.