[MW:9134] Thickness qualification range for duplex SS with PWHT (ASME IX)

Dear Mr Pedro Alvarez

QW407.4 has been revised to include P10H, Please refer 2010 edition of ASME Sec IX, and maximum qualified thickness would be 27.5mm in your case.

 

 

Best regards

B. Raghuram

 

-----Original Message-----
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Pedro Alvarez
Sent: Friday, January 07, 2011 2:09 PM
To: Materials & Welding
Subject: [MW:0] Thickness qualification range for duplex SS with PWHT (ASME IX)

 

Dear all,

 

I have a enquiry concerning the base metal thickness qualification

(ASME IX) range for a welding procedure of duplex stainless steel with

solubilization PWHT. I tried to get a response from ASME, but I did

not receive any answer.

 

According to QW-250s tables PWHT, for many welding technologies the

PWHT limits the maximum qualified thickness as per QW-407.4. This

article says: "For ferrous base metals other than P-Nº 7, 8 and 45,

when a procedure qualification test coupon receives a PWHT exceeding

the upper transformation temperature, the maximum qualified base metal

thickness, T, shall not exceed 1.1 times the thickness of test

coupon".

 

As far as I concerned, upper transformation temperature is Ac3

(ferrite to austenite transformation while heating) for a ferritic-

perlitic carbon steel.

 

If I have a coupon of 25 mm thickness of Dupex SS and I apply a PWHT

at 1100ºC + Water quenching, ¿what do you think should be the maximum

qualified thickness range? 27.5 mm or 50 mm.

 

Regards.

 

Materials Science Ph.D Pedro Alvarez

LORTEK - Joining Technologies Research Institute

Spain