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[MW:14038] RE: Temper bead QW 402.23 and 24 ASME SEC IX

By Materials & Welding
James,
 
Please see the interpretations below. Essentially they're applicable if any in situ weld repair has to be made on a process or steam or water piping  where any flow is involved. In most of the circumstances  this requirement do not kick in.But in cases of online repairs one has to look into these for PQR qualifications.
 
Thanks.
 

Pradip Goswami,P.Eng.IWE

Welding & Metallurgical Specialist & Consultant

Ontario, Canada.

Email-pgoswami@sympatico.ca,

pgoswami@quickclic.net

 

QW-402.23 For test coupons less than 11⁄2 in. (38 mm) thick, the addition of a cooling medium (water, flowing gas, etc.) to the back side of the weld. Qualification on test coupons less than 11⁄2 in. (38 mm) thick with a cooling medium on the back side of the weld qualifies base metal thickness equal to or greater than the test coupon thickness with and without coolant.--Essential Variable when hardness testing is asked for procedure qualification testing. The presence of cooling media increases the rate of cooling in the wetted surfaces, increasing hardness

QW-402.24 Qualification with a cooling medium (water, flowing gas, etc.) on the root side of a test coupon weld that is welded from one side qualifies all thicknesses of base metal with cooling medium down to the thickness of the test coupon at the root or 1⁄2 in. (13 mm), whichever is less.--Essential Variable when impact testing is asked for procedure qualification testing

 

From: James Mathew [mailto:jamesmathewtrading@gmail.com]
Sent: Saturday, March 31, 2012 4:18 PM
To: pgoswami
Subject: Temper bead QW 402.23 and 24 ASME SEC IX

Dear Sir
Can u please guide me regarding the term fluid backing. The Standard term means of backing is support the weld metal in the root, but how is it possible with water gas.
Kindly clarify if this term is different from normal backing and please let me know where is it mentioned in ASME codes.
It will be of great help if u advice me.
Thanking you in advance
With Regards,
James

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