Hi,
I just read the paper by L.C. Peng from Peng Engineering "Understanding Piping Code Stress Evaluation Paradoxes And ASME B31.3 Appendix P" released in August 2013. According to this paper, B31.3 Appendix P "is a poorly conceived, unsafe alternative rules to the main code".

This conclusion is reached by comparing the design by rules approach from B31 and B31.3 appendix P with the design by analysis approach from ASME B&PV Section III Class 1 Components.

I was wondering if any of you had comments or opinions regarding this paper.

Thanks for your input,
Biss

Isn't there anybody that wants to comment?

Have a nice week-end,
Biss

L.C.Peng has a formal request at B31.3 to remove Appendix P. At this week's B31.3 meeting, the design committee agreed to ballot the removal of Appendix P from B31.3 along with moving other Appendix P improvements to the base Code. I believe these changes will be accepted by the section committee but I do not expect this to make it in the 2014 Code book.
Appendix P provides a simple workaround the declaration of a single SL for equation (1b). [CAESAR II uses the max SL in (1b).] But the concept of "alternate rules" causes misunderstanding with many engineers.
Peng's engineering point was discussed at the meeting, his opinions are valued by the committee, but in my opinion, his conclusions were not generally accepted.

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"But the concept of "alternate rules" causes misunderstanding with many engineers."

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I guess this is the real problem. Maybe you should give a better guidance regarding this Appendix P (and B31.3 as well).

While being obscure prevent beginers to perform calculations (in fact do not prevent it at all),it will also prevent clients to understand the real problems and to have basis in rejecting poor calculations. It is a matter of "who is the strongest stone".

And may I ask which part of his conclusions are not accepted and why?

Thanks,
Biss

http://becht.com/blog/what-is-the-future-of-asme-b31-3-appendix-p#!

http://becht.com/blog/categories/listings/piping

And some other interesting things.