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Re: [MW:10890] Duplex Claded Eqipt PWHT

By Materials & Welding
No PWHT for duplex clad as temp between 300 to 850 degC will form intermetallic phases and affect the corrosion properties. suggest  u carry out PWHT of equipment  with barrier layer of 309L Mo  and then deopsit duplex over barrier layer.
regards
vanchi

On Fri, Apr 29, 2011 at 10:01 AM, Prakash Hegde <pb.hegde@yahoo.com> wrote:
Dear Friends
I have a query about The Duplex  cladded E quipment having base material SA 516 Gr70 of 50mm thk and clad of Duplex (3mm )
The eqipment require to undergo PWHT at 600C The Joint is clad restored by Duplex weld
 
i) Does the PWHT at 600C will affect  the Corrosion properties of Duplex weld (Corrosion test like IGC,Pitting corrosin,etc  as per GS8)
ii) If yes do we require to carry out PWHt at lower Temp.
 
Regards
Hegde P.B.
08805593046
 

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