Weld qualifications (Modified by Christopher Wright)

From: <Christopher>
Date: Thu Sep 27 2007 - 22:26:00 EDT

I need some clarification on weld procedure qualifications, so I can stick to my guns or issue an apology. It has always been my understanding that a welder who qualifies to weld P-1 material does not also qualify to weld materials with higher P-numbers, particularly low or high alloy steels. I said as much in the following thread on the ASME web site and 'someone' [not CPW] said I didn't know what I was talking about and cited QW-423 as proof. I claim you can't possibly weld a P-8 material based on qualifying with a P-1 material, if only because most of the essential variables are different, starting with the fact that different electrode specifications are used. Moerover Chrome-moly steel usually requires pre-heat which also represents a significantly different WPS. Would someone be good enough to read over this thread and tell me what I missed, if anything? In particular this sentence "Basically, you can weld carbon and chromolly GTAW / SMAW to twice the thickness tested for each process and stainless you can weld GTAW to twice the thickness tested.(GTAW thickness only)" seems like nonsense.

>   Re: Alternate base metals for welder qualification
>     by sfeder - September 24 at 8:36 PM CT
> Learner,
> If you qualify on P1 material with GTAW root run this is an F No 6 so
> you are qualified for all F No 6. This will mean you can GTAW weld
> carbon, chromolly and stainless steel as they are all F No 6.The
> addition of purging gas is a non-essential variable so stainless steel
> is OK.You cannot do it the other way (test on s/s to qualify for c/s)
> as deletion of purge is an essential variable.
> However, it is different with the SMAW as the carbon and chromolly
> fall under F No 4 and the stainless steel is an F No 5.
> Basically, you can weld carbon and chromolly GTAW / SMAW to twice the
> thickness tested for each process and stainless you can weld GTAW to
> twice the thickness tested.(GTAW thickness only)
> Hope that helps,
> Regards,
> [not CPW]

> ----------- Reply----------------
>    Re: Alternate base metals for welder qualification
>     by Christopher Wright - September 25 at 10:09 AM CT
> >If you qualify on P1 material with GTAW root run this is an F No 6
> so you are qualified
> > for all F No 6. This will mean you can GTAW weld carbon, chromolly
> and
> > stainless steel as they are all F No 6.

>

> This is absolutely wrong. Qualification on P-1 materials does not
> qualify welding on higher P- numbers. Moreover, the weld procedures
> and particularly the consumables are all different for chrome-moly and
> stainless steel, so it requires different procedure and welder
> qualifications. The F-numbers refer to various electrode coatings.
> P-numbers refer to the base metal and are listed in Section II.
> A-numbers refer to the filler metal alloy content

>

> >Basically, you can weld carbon and chromolly GTAW / SMAW to twice the
> >thickness tested for each process and stainless
> In general this is wrong, too--depends on the specific materials and
> the thicknesses qualified on the WPS. Read it.

>

> Sounds like [not me] is having you on.

>

> Christopher Wright

>

> : Alternate base metals for welder qualification
>     by [not CPW] - September 25 at 6:44 PM CT
> Christopher,
> Please get your facts correct before you go making statements about
> things you obviously don't have a clue about.
> ASME IX Clause 423.1 Alternate base metals for Welder Qualification
> states if the base metal used for qualification tests is P1 through
> P11 you are then qualified for production welding P1 through P11.
> If you weld on P1 you are qualified to weld P1,P3,P4,P5,P6,P8,P9,P10
> and P11.(There are others but I cannot be bothered listing them all)
> If you weld with SFA 5.18 GTAW wire (F No 6) in the qualification test
> you are qualified to weld all F No 6s.(This includes stainless steel
> and chromolly wire)

>

> I don't know where you are getting your information from but I suggest
> the first thing you should do is obtain a copy of ASME IX and read it
> and then maybe you would realise how stupid your statements are,
> [not CPW]
>   Reply
>      

>

>    Re: Alternate base metals for welder qualification
> [not CPW] has it correct. The welder, performing a P1 qualification
> is qualified to weld P1 - P11, etc., etc., as permitted by ç. It seems
> some folks are confusing performance qualification (QW-300) with
> procedure qualification (QW-200). A procedure qualified with P1 - P1
> materials may NOT be substituted for welding P1 to any other P number
> whereas for performance, a welder qualified with P1 materials using F6
> filler (example only) may weld all of the base metal combinations
> permitted within QW-423 so long as the essential variables are
> followed. If in doubt, visit www.sperkoengineering.com Mr. Sperko is
> Vice Chair of ASME IX and I am POSITIVE he will concur.
>   Reply

---

Christopher Wright P.E. |"They couldn't hit an elephant at <a href="/group/PipingDesign/post?postID=tuaqCaEqmfiAzAyLZxVzMDytiaeRfJ3aljmS1aC94ESUb7kk5kgD4DtLs7H-S6j3J13LJV2K8Fg_nilR8w">chrisw@skypoint.com</a> | this distance" (last words of Gen.

____________________| John Sedgwick, Spotsylvania 1864)

<a href="http://www.skypoint.com/~chrisw">http://www.skypoint.com/~chrisw</a>

[Non-text portions of this message have been removed] Received on Thu Sep 27 22:26:00 2007