Understanding ASME VIII Div 2 Eq (5.29) and 5.5.3

[Doodler3D]

Hi.

Is there a guide to understanding how effective equivalent stress range is calculated? Also, is there a book for the theory behind it? Code-wise, I understand that it is the difference between the (Pl+Q+F) stress at the node/location of interest for the max and min value of the fatigue cycle, but I think the tensor notation has confused me. Furthermore, if I have 2D mesh elements, does the code allow me to proceed with calculations from 5.5.3 using membrane, bending and peak stress values from ANNEX (5-A.5) to (5-A.7)?

Edit: Additionally, does a Von Mises peak stress intensity value serve any purpose?

Thank you.

 

[Doodler3D]

I guess these were terribly worded questions. Nevertheless, I may have found my answers. Having no mentor sucks.

 

[Some Curious Guy]

I do not know the answer to your question as FEA is not my forte. However have you got a copy of PTB-1 Criteria and Commentary of Sec VIII Div 2. This document gives background and logic behind the equation and rules in the code. Hopefully you may find your answer there or it may direct you to some other reference.

I totally understand your frustration. I have being there. The industry and the engineering scope is so vast that you have to speak with many people to get an answer. Take solace from the fact that most of us are self taught.

Regards

 

[Doodler3D]

Beyond PTB-1, a fair bit of my self learning is from previous FEA work done through consultants. On numerous instances, they used their own methods to arrive at conclusions. Additionally, some reports indicated ASME 2010/2013 in the bibliography but ended up having 2004 code methods.

 

[TGS4]

There are training classes on the the topic of ASME Section VIII, Division 2, Part 5. Let google help you. Look for something at least 3 days long - 4 days is even better. Skip anything that ranges from 2 hours to 2 days - they will be too superficial. Some companies are offering virtual training so you can be anywhere in the world and access the training.

 

[Doodler3D]

Yes its a new job, I started a couple of months before the lockdown, and plans were on to attend a full course in person later this year, plans and priorities both changed.