Does ASME VIII-1 permit FEA resolution for design calculations of pressure vessels?

[JPearson84]

Gents,

let me preface this by stating that I am not a pressure vessel engineer & have never read through the tome that is ASME VIII.... that being said I do work as a project engineer for a packaged equipment vendor, I have sourced a plate & frame heat exchanger for utilization in one of my packages & my subvendor has supplied design calculations resolved utilizing FEA methods. My client has rejected these code calcs as their project requirement is that the heat exchanger be designed to ASME VIII-1. My limited understanding is that FEA methodology is outlined in VIII-2.

This requirement was given to my subvendor prior to awarding the order & they made no mention of any concerns. As indicated above, since I do not have familiarity with the code requirements I have left it with my sub to prove that their design calculations should be acceptable.... well almost 9 weeks later & I haven't gotten anywhere.

Is there a helpful member of this forum who could maybe point me to a section or clause in VIII-1 that might indicate if & when FEA methodology is acceptable?


frankly my opinion on the matter is that I'm basically buying a standard product (a plate & frame heat exchanger is damned close to "off the shelf"), and that if the calculations complete are correct per the physical & process constraints, and that if the applicable governing / registering body accepts the calcs & permits registration of the equipment I simply do not care whether said calcs are done on a napkin in crayon or utilizing state of the art FEA tools...

Anyways, as always thank you for any help!

Jon P
EIT

 

[rumandcola]

Usually plate and frame heat exchangers can be calculated as non-round bolted flat heads per UG-34 and then nozzle calculations to justify the openings. If this particular design cannot be calculated with those rule, you can use the U-2(g) clause which allows alternate methods of analysis such as FEA.

 

[doct9960]

Jon P,

FEA may be used when the ASME Code does not contain rules to cover the design and construction of the pressure part.

As mentioned by rumondcola, plate & frame heat exchangers are usually designed to UG-34. If this is the applicable Code rule, then you cannot use FEA.

 

[TGS4]

JPearson84 - with regards to your opinion - physics and engineering aspects aside, in many jurisdictions around the world (you didn't say where you are located), there are legal/statutory requirements that disagree with your opinion.

Otherwise, I agree with the above responses above.

 

[JPearson84]

Thanks everybody!

@TGS4 - you'll note in my opinion I mention that the applicable governing body has to accept the calcs