AWS Welder Qualification (Backing & Back gouging matters)

Date 08-12-2009 02:19 Edited 08-12-2009 04:05

Dear you all,

We are going to qualify welders for our project, the welding process applied is FCAW and welding from both side, therefore we are going to test the welder by back gouging. However we don't know yet if the welder qualify on joints with back gouging qualifies for production joints that are backing or not? Could any body help me to solve the question?
Sorry, please add more information that I am going to qualify the welder according to AWS D1.1.

Thank you very much and looking forward to hearing from you soon.

By ctacker (****)

Date 08-12-2009 02:35

As a welding Engineer and Inspector, shouldn't that be an easy one to look up? Whatever code your working to!

By eekpod

Date 08-12-2009 10:18

Cong,
Look at pg 131, 4.23 CJP Groove welds for non-tubular COnnections. "Note that qualification on joints with backing qualifies for welding production joints that are back gouged and welded from the second side".
I have never personally given a test where they back gouge the test plate, we always use a B/B for the test because of the note above covers even when they have to remove it.
Hope this helps
Chris

By swnorris (****)

Date 08-12-2009 13:16

I've often wondered the reasoning behind that. It seems that backgouging and welding from the second side adds another degree of difficulty when compared to using a backing bar and welding from one side.

By truongthien Date 08-13-2009 01:36

Dear Swnorris, Cong and all associates,
From the Para 4.12 (1) of AWS D1.1 we found that welder qualification by a butt joint with backing or with backgouging is indeed acceptable. Para 4.12 (1) specifies for Tubular connection which has no any changes in positions for the welder during his ferformance.
For Non-Tubular connections, Para 4.23 doesn't specifies clearly just because qualifiaction by a butt joint with backing or with backgouging on 1G, 2G ,3G are completely similar and would be accepted. However at 4G position, the secondside welding after backgouging will be in 1G postion and in this case qualify by joints with backgouging in 4G position does not qualify for production joints with backing in 4G position.
Hope that we have same Code clarification on this issue.
Rgds
Truong Thien

By cong nguyen (**)

Date 08-18-2009 03:04

Thank you very much for your clarification Mr Thien, it is very clear now.

By DAYANARA (**)

Date 08-13-2009 00:33

Dear

AWS D1.1, 1.5, ASME secction IX, allow welder qualification in V groove Weld with backing and weld production with or without backing, but shall be backgouge root to sound metal before weld secod pass.
You qualify with back gouge, yuo can weld with backing plate also.
DAYANARA