Need advice on FEA results
Need advice on FEA results
(OP)
Hi,
The model being analysed is that of a lifting lug welded to the bottom ring of a support ring halfway up along the vessel.
In the FEA results I am reviewing, the overall von Mises stress plot comes out as 614.99MPa. The person doing the FEA then took a Stress Classification line at this spot through the thickness of the bottom support ring plate, and the membrane+bending stress came to 490.8MPa.
Now membrand+bending stress of 490.8MPa is less than 3 times S, with S being 173MPA (2/3 of the yield strength of SA-516 70), and thus passes.
My concern is the 615MPa von Mises stress. I am not sure of how to approach this value. The value seems very high, does it mean the analysis shows that the model will fail?
The model being analysed is that of a lifting lug welded to the bottom ring of a support ring halfway up along the vessel.
In the FEA results I am reviewing, the overall von Mises stress plot comes out as 614.99MPa. The person doing the FEA then took a Stress Classification line at this spot through the thickness of the bottom support ring plate, and the membrane+bending stress came to 490.8MPa.
Now membrand+bending stress of 490.8MPa is less than 3 times S, with S being 173MPA (2/3 of the yield strength of SA-516 70), and thus passes.
My concern is the 615MPa von Mises stress. I am not sure of how to approach this value. The value seems very high, does it mean the analysis shows that the model will fail?





RE: Need advice on FEA results
I would caution that classifying the M+B stress as P+Q may not necessarily be conservative for your specific situation.
Make sure that the SCL is "valid" per Appendix 5-A. Also, the current limit on P+Q is Sps, which is the greater of 3S or 2Sy.
RE: Need advice on FEA results