ABSA CRN Approval using Compress's FEA module

[dguard91]

Anyone having trouble submitting Compress's FEA analysis for nozzle loads to Alberta for a CRN? We had a FEA analysis of a offset nozzle rejected using Compress's FEA option. Alberta then set us a specification "AB-520 document, Finite Element Analysis (FEA) Requirements" to follow that was really ridiculus.

 

[TGS4]

Explain why you think that AB-520 is "ridiculous"?

 

[Bobfromoh]

Well I have two questions concerning AB-520.

1. The statement "The turn angle of each element used on inside fillet radii must be indicated"
What does this statement mean?

2. The statement "This section of the report must include a proposed method to verify that the model results reflect the real response of the physical pressure equipmnt"
How could you verify this statement other than to say the deflection and stresses look resonable?

 

[TGS4]

Bobfromoh - Here's my take on that.

1. What is the total angle of your inside fillet radius? Take 90° as an example. How many elements do you have around that fillet radius? Take, for example, 6. Therefore, the turn angle of each element is 15°.

2. Define "look reasonable". If you have checked the far-field hoop stress, and it exactly matches the PR/t stress, and the far-field longitudinal stress exactly matches PR/2t, then you're probably pretty close to achieving this requirement. You can also discuss deflection (or strain) measurements that could be made in-service that would validate your FE model.