Fatigue analysis for the vessel

[balamech]

Fatigue analysis need to be included in the design for ASME sec VIII div.1, If not can you please explain?

 

[C2it]

What exactly are you asking ?

 

[TGS4]

I'm not entirely certain what you are asking either, but UG-22(e) is very clear on this point. Cyclic loading must be considered. Now, note that Division 1 does not have rules for how to handle these loading situations, so you must defer to U-2(g).

 

[08tramp]

There is a method described in the Div II, wherein there is a graph explaining how to calculate it.I shall tell you day after tomorrow as to how to perform fatigue analysis based on the information in the DIV II, because it is lying on my computer in the office. It is an excel sheet.

 

[08tramp]

Presently, VIII-1 doesnt list any rules for fatigue evaluation of components.When fatigue evaluation is required in accordance with UG-22 or U-2(g)of VIII-1, the general practice is to use the VIII-2 fatigue criteria as a guidance up to the temperature limits of VIII-2.At temperatures than those given in VIII-2, the rules of III-H are followed for general guidance. Other fatigue criteria, such as those given in other international codes and ASME B31.3, may also be considered as long as the requirements of U-2(g)of VIII-1 are met.

VIII-2 contains detailed rules regarding fatigue. Paragraph AD-160 gives criteria regarding the need for fatigue analysis.

Please read the cited paragraph from the VIII-DIV 2, and you will come across two conditions A n B to be met in order to evaluate whether fatigue calculation is necesary.