farzam-
farzam-
Yes, there are times when your standard vessel design software will not have a module where you just plug in numbers and get the answers. These are the times which "separate the men from the boys." You could do some hand calc's, but FEA will be a better approach. Follow the guidelines for protection against buckling in the 2007 editions of either VIII Div. 2 or API 579-1 / ASME FFS-1. If you are within the original corrosion allowance, then you can work the evaluation as an alteration; otherwise you are probably in the world of Fitness For Service.
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