ASME sect VIII nozzle reinforcement calc.
ASME sect VIII nozzle reinforcement calc.
(OP)
Quick question when calculating area supplied by the repad towards nozzle compensation:
Formula from UG.37.1
A5= (Dp-d-2tn)tefr4
I have been using the inside (corroded) diameter of the nozzle as "d"
but my answer key is showing "d" as being the origional outside diameter of the nozzle?\
Which is correct?
Formula from UG.37.1
A5= (Dp-d-2tn)tefr4
I have been using the inside (corroded) diameter of the nozzle as "d"
but my answer key is showing "d" as being the origional outside diameter of the nozzle?\
Which is correct?





RE: ASME sect VIII nozzle reinforcement calc.
d = finished diameter of circular opening or finished dimension (chord length at midsurface of thickness excluding excess thickness available for reinforcement) of nonradial opening in the plane under consideration, in. (mm) [see Figs. UG-37.1 and UG-40]
To answer your question, neither one is correct. You may view the OD of the nozzle as the dimension, but it is, in fact, the ID of the shell cutout.
RE: ASME sect VIII nozzle reinforcement calc.
Your answer is correct.
Go look into some of the example problems in PTB-4 and Appendix L-7.4 (pre-2013 Code edition).
RE: ASME sect VIII nozzle reinforcement calc.
The area that requires reinforcement is indeed the as-corroded ID of the nozzle.
However, the question is asking what the repad contributes to that reinforcement. After the full-penn weld, the effective inner limit of your repad is the OD of whatever nozz you are working on.
RE: ASME sect VIII nozzle reinforcement calc.
But also see UG-40 for various configurations.
jeff3300, you've got an answer key? How nice. I could sure use one for the design I'm currently on :)
Regards,
Mike
RE: ASME sect VIII nozzle reinforcement calc.
Appendix L-7.4 was an excellent resource I had overlooked.