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[MW:26948] Question please and follow-up 3 questions- Can anyone advise the thought/answers please? Thanks and Best Regards

By Materials & Welding


How to apply Cyclic Assessment/Analysis requirements of ASME VIII Div. 2 to a "standard" Div. 1 vessel design please?

 

Then follow-up 3 questions are as below for the scenario

 

Scenario

 

The supplier is offering a "standard" ASME VIII Div. 1 dryer vessel (pressure swing) with proven operating experience in excess of the 30 year design life required by the project.

 

The Project Vessel Specification calls for fatigue analysis according to Div. 2, when required,

 

It appears that Div. 2 section 5.5.2.1 c calls for a fatigue analysis if specified number of cycles is greater than 10^6, even if comparable experience can be proven (we have over 2x10^6 cycles). 

 

Questions:

  1. Are there any circumstances or, code exceptions, whereby proven experience can override Div.2 section 5.5.2.1.C?

  2. What  is the criteria for determining if a vessel is in cyclic service i.e. how to interpret the Div. 2 assessment criteria

  3. If the Project Specification had not called out ASME VIII Div. 2 for assessment / analysis, what are the minimum qualification criteria that would be required?  In this case would we accept "experience with comparable equipment" without further analysis?  What is the standard, if any? 

 

 


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