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[MW:7585] Cyclic Thermal Loading material Selection 800H / 316H /304H -Regarding

By Materials & Welding
Dear

We have situation where in - - due to process conditions the
equipment has cyclic loading more or less of the below cycle


H2 @ 700 Deg C - two- three days - N2 @710DegC - two-three days -
Co2+N2@ 200DegC one day .

Proposal was to use 800H material initially (reason for Selection of
Material not known )
in the last stage , we came to know that existing plant has one 304H
which is working fine .

I referred NACE for guidance - it indicates 316 as good material for
H2S materials in high temperatures but couldnt find the N2 & Co2 +N2
part . Some say 316 stabilised ...

ASM Metals hand book (quite scared me ...coz few case studies have
failures within Days if not in Weeks & Months ) referred API 941 . (I
dont have a copy , does this Standard have any recommendation of
material for the above??? )

-recommendations go on...........

anybody has experience of the same / somewhat close cycles in their
Process Plant? -

Any path forward will help a lot ...

---------------------
HAPPY DUSSERA !

Regards

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