Welder quailification for well head installations?

Date 09-25-2009 01:33

After some more reasearch on the forum I realized I might need to explain what type of joint design thi would be. Basically its a large socket weld with a multi-pass fillet. The head slips down over the OD of the pipe. For anyone who doesnt know what a well head is. Maybe I will get some results now.......

By G.S.Crisi (****)

Date 09-25-2009 17:37 Edited 09-25-2009 21:19

You've used that procedure previously on 10 well heads. So, we may safely assume it's a good procedure, although it's not qualified. Your present customer insists that he wants a qualified welder to do it. Now, if the procedure isn't qualified, there's no welder who is qualified to make it. So, what you've got to do is to qualify the procedure AND the welder at the same time.
Simple: the welder will weld the well heads following the mentioned procedure, and the specimens will be tested according to the applicable standard (ASME IX?). If the specimens are approved, both the procedure AND the welder will be approved.
If the specimens aren't approved, there are two possibilities:
1. The procedure is no good.
2. The welder is no good.
As we don't know which one of them is true, ANOTHER welder will re-weld the well heads according to the said procedure and the tests will be repeated. There are two possibilities:
1. The tests are approved. In this case, it's assumed that the first welder was no good and the procedure AND the second welder are qualified.
2. The test aren't approved. In this case, it's assumed that the procedure was no good and neither the procedure nor the second welder are qualified (no welder can be qualified to follow a procedure that's no good).
Giovanni S. Crisi
Sao Paulo - Brazil

By cmays

Date 09-25-2009 19:06

The product is always hydro tested after the weld is made in the field. Can a cwi witness this test and consider that a qualified procedure if the weld passes the hydro test that is specified in the procedure? This is the first time Ive run into this dealing with this particular field weld. I am welding with a procedure that has been specified by the customer along with a testing procedure to follow. What Im trying to get is a certification for that procedure or where there might be a section in asme that covers socket welds of this size.

By G.S.Crisi (****)

Date 09-25-2009 21:23

I'd say that passing hydro test doesn't qualify neither the welding procedure nor the welder who made it. Qualification standards I'm familiar with (ASME IX, API 1104) say nothing on hydro tests as a qualification criteria.
Giovanni S. Crisi

By cmays

Date 09-26-2009 01:47

I didnt think so either. OK , let me ask you this then. If the customer wants the welder to be certified as per ASME sec IX is there a way to qualify the welder that covers all groove welds and fillet welds pipe and plate (say 6G pipe test for example) and can the weld be tested with radiography alone?

By waccobird (****)

Date 09-25-2009 18:11

cmays wrote "The same procedure Ive been using on 10 other customer's well heads." what are you doing using unqualified procedures? If you can use them why can't they?
You Qualify a welder to a process and the restrictions of the actual test, position, material thickness,.... I don't have the codes for the welds you are writing of. But there should be Welder qualification tests in them. Hope this helps more than it hurts