Re: [MW:4473] Why maximum PWHT temp shall be at least 20 °C less than tempering temp.

The pwht temperature must be lower than the lower transformation temperature in order to avoid microstructure alterations.

From: "Pradip Patil" [pradipp@godrej.com]
Sent: 08/03/2010 11:40 ZE5B
To: <materials-welding@googlegroups.com>
Subject: [MW:4472] Why maximum PWHT temp shall be at least 20°C less than tempering temp.

Dear Sir,

Why maximum PWHT temp for CS and Low alloy steel materials shall be at least 20°C less than tempering temp?

With Regards,

Pradip Patil.

Comments

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