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[MW:12868] Post Weld Heat Treatment

By Materials & Welding

Dear Experts,
 
We know very well about PWHT cycle having 1)Rate of Heating from certain temperature, 2)Soaking time @ Soaking Temp. & then 3) Rate of Cooling upto the certain temp.
 
My query is that, What are the roles of Rate of heating, Soaknig time & Rate of cooling during PWHT? How we get acceptable hardness values by using these? Is there any unacceptable hardness values are found after PWHT then how will rectify?
 
With Regards
 
 
Srinivasu V
Welding Engineer

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