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[MW:7668] RE: 7585] Cyclic Thermal Loading material Selection 800H / 316H /304H -Regarding

By Materials & Welding

Hi Mayank,

The design environment operating conditions are way too much of austenitic stainless steel. That's why  Alloy 80 selected. If you could forward some more information on the operating environment, the extent of cyclic services (all round the year or only a temporary phenomenon), design  conditions of the equipments etc, more relevant answers to your query could be found.

Thanks

Pradip Goswami,P.Eng.
Welding & Metallurgical Specialist & Consultant
Email-pgoswami@sympatico.ca,
pgoswami@quickclic.net

-----Original Message-----
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Mayank .
Sent: Friday, October 15, 2010 10:00 AM
To: materials-welding
Subject: [MW:7585] Cyclic Thermal Loading material Selection 800H / 316H /304H -Regarding

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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