I have a brazed heat exchanger that consists of multiple flat plates brazed together. Such brazed flat plates form multiple channels. The exchanger looks like a box - like a square. Construction is too complicated to be evaluated per UG-34 or any other paragraph of VIII-1. Therefore UG-101 is used. Now, we have used UG-101 (p) for MAWP determination, since these are all flat plates. We are being challenged by a jurisdiction in Canada. They say that UG-101(p) is not applicable to end plates. According to them UG-101 (p) is applicable to inner plates but not to end plates.
I am assuming they would like us to use UG-101(m) and that would result in much lesser MAWP.
Please let me know your opinion - would UG-101(p) be applicable for end plates as well.
Thanks in advance.