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Re: [MW:25129] PWHT

By Materials & Welding
Hi!
Selecting the Time and temp for PWHT is important  as it affetcts the mechanical properties
For which LM (Larsen Miller parameters ) helps
Increase in soaking time beyond certain limit deteriorates the mechanical properties
e.g. As per LM parameters  PWHt soaking temp of 650C with  2hrs soaking time is equivalent of 9hrs soaking time at 620C (even though code says for P1 soaking temp min 593c to below AC 1 )
Therefore you can imagine the importance of PWHT temp and time
Regards
Hegde




On Wednesday, 20 July 2016 9:28 PM, ishwar kumar <ish8623@gmail.com> wrote:


Dear experts

My query is what happens if the soaking time during PWHT is increased beyond the specified minimum time. I know section 8 days minimum soaking time only.

Suppose if required soaking time is 2.5 hours and actual soaking time is 5 hours

Regards
Ishwar Dhiman
Cswip 3.1,ASNT NDT Level-II

Sent from my iPhone

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