[hvn83]

I’m sorry but so far no one has really understood, nor answered, my question.
To put it in perspective again, here comes a new formulation of the same question:

If you use dual certified have 304/304L ASME B16.5 flanges, what is/are the max. temperature (limits) these flanges may be used to, and WHY?
B16.5 namely does not address any reasons why 304L flanges are limited to 425 deg C.
It only says 304 flanges may be used to 816 deg C, and 304L flanges up to 425 deg C.
Thus, what temperature limit should be used now for dual certified 304/304L?

PS: if Im making a mistake, i.e. my question has been answered, Im sorry if I understood the respective reply wrong. Just let me know where the answer is mentioned.