Rectangular or NonCircular Pressure Vessel per Appendix 13 of VIII-1

[prin1939]

This is a couple of code questions regarding the joint efficiencies and allowable stresses of Appendix 13 of ASME BPVC Section VIII-1, particularly 13-7(a).

1. Joint Efficiencies. When a rectangular pressure vessel is built from 6 plates (2 top plates, 2 side plates, and 2 end plates), does that pressure vessel have "butt joints"? I assume the answer is no because the joints create corners.

If the attachments are, or are not, butt joints, how do I determine the efficiency of those joints assuming I have done no type of radiography or equivalent inspection?

2. Stresses. When looking at the Total Stress Formulas in 13-7(a)(3), what are the associated allowable stresses for each of the formulas given?

In the example problem 13-17(a), which runs through the formulas of 13-7(a), the code appears uses 2 different joint efficiencies and determines 2 different allowable stresses to compare against the calculated stresses. I need to know what allowable stress is associated with what calculated stress.

Thanks.

 

[prex]

1. You have corner joints. No efficiency is used for corner joints. You need to size and calculate them individually by using the stresses calculated for the joint itself.
2. The allowable stresses are specified in 13.4

prex

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