Welder Performance Qualification FAQs

This article discusses some of the welder performance qualification FAQs that arise in a welding engineer’s mind in the process of welders’ qualifications in accordance with ASME Section IX.

welder-qualification-section-ix

Does A Person Helping The Main Welder Need To Be Qualified As Per Section IX?

In my shop, for important joints – often more than one welder is assigned at a time to weld a joint.

A joint gets considered important when it is desired to weld it without repair in the first shot. This happens commonly for cir-seams that are welded by SAW process. Such joints generally fall in the critical path of the project. Hence, obtaining a good weld in the first shot becomes of paramount importance, in the interest of speedy completion of the project.

Up to three welders get assigned at a time to weld the joint.

Other than the main welder who is qualified to weld the joint as per Section IX, the other two basically serve as his helpers. One would help in cleaning the joint after each bead, and keeping up the supply of fresh flux in the funnel; another would adjust the parameters in the machine etc., if required; under the supervision of the main welder.

One of the authorised inspectors in my factory once demanded the Performance Qualification record of the two helper welders. Incidentally, all the welders in that shop are qualified welders too, for making the joint in question. I had no problems.

But this makes a question arise in mind. It is the main welder who is the commander of the ship. He remains accountable for the joint. The other two are merely helping him with mechanical tasks. Do they need to be qualified too, as per Section IX?

What does the Code intend?

An interpretation issued by ASME in 2008 addressed this question. A person making adjustments to the welding equipment settings, under the supervision and control of the welder performing the weld does not need to be qualified as per Section IX.

Documenting Multiple Performance Qualifications

When Multiple Welders Are Qualified Through A Single Test Coupon, Should The Performance Qualification Record Of Welders Be Recorded On A Single Form? Or Multiple Forms?

This question also arises when one welder is qualified in a single test coupon for multiple processes. For each process, should a separate Form (say, like the one suggested in QW 484A/QW 484B) be generated for each process? Or, since the welding happened on a single coupon, the entire episode should be recorded on a single Form?

The answer to this is that Section IX does not stipulate any requirement in this regard. The manufacturer is free to record the Welder’s Performance Qualification in any manner he wants, so long as the information required by QW 301.4 is documented.

In my personal opinion, it is better to make separate records. It is easier to refer to the Qualification Record that way.

Radiographic Examination Of Welder’s Performance Qualification Coupon

A Small Segment Of Weld Length Of My Welder’s Performance Qualification Test Coupon Is Not Ok In RT. Can My Welder Still Be Considered As Qualified As Per Section IX?

Consider this. You qualified your welder on a 250 mm long plate. During RT examination, it is found that there is a 20 mm long segment of weld length that is unacceptable as per QW 302.2. However, there is a clear 150 mm length available that is acceptable in RT.

Has your welder passed in this qualification?

QW 302.2 requires that a minimum length of 150 mm shall be examined. Citing this, one might argue that the welder in question above has passed this qualification.

However, in the eyes of the Code, the welder is not considered to have passed in the qualification, if this happens. Although Section IX has not specifically addressed this anywhere; in line with its philosophy – Code does not consider the welder in this situation, as qualified.

This is logical too. A test coupon is a miniature representation of the production joint that the welder is going to be assigned on. If a portion of the test coupon is not acceptable, it would be advisable to take a retest.

An Interpretation similar to this effect was issued by ASME, back in 1985. Interpretation number IX-83-153.

When Qualifying A Welder On Grove Weld On A Plate, Through Volumetric NDE Method, Is It Permitted/Required To Weld An Extra Length Of The Coupon, Such That The Extreme Ends Can Be Discarded From RT?

When a welder is qualified through mechanical tests, QW 463.2(a), (b), (c) clearly mention that a small piece at both extreme ends is to be discarded, and excluded from the mechanical testing. For volumetric NDE option, whether a similar discard piece at the extreme ends is required/permitted is not addressed in Section IX.

It makes sense to discard a small piece at the ends, since the weld soundness is affected due to the edge of the coupon. In my organization, we do follow this. A 25 mm piece at the ends is omitted from evaluation in RT. Is this permitted by Code?

Usually, any reasonable Authorised Inspector would not object to such a matter. However, industry is replete with overzealous inspectors who would like to do every single thing by the book.

The matter was clarified by ASME through an Interpretation, in 1987. In the Interpretation IX-86-79, the ASME ruled that as long as the radio graphed portion is a minimum of 150 mm, it is alright to have a length longer than 150 mm, so that the start and stop ends of the test coupon are not included in the radiograph.

Repair On A Welder Performance Qualification Coupon

Is A Welder Allowed To Make Any Repairs While Making A Test Coupon For Welder Performance Qualification?

Once, a welder qualification was underway in my shop. A representative of the authorised inspector was present to witness the weld.

The qualification consisted of a groove joint on two 6 mm thick, 50 mm OD pipes, in 6G position, with GTAW process. As part of the plan, after the root pass, the authorised inspector is required to visually inspect the weld for incomplete/excess penetration, weld bead appearance etc.

 After laying the root pass, it was noticed from the ID side, that incomplete penetration has occurred for around 5 mm of the weld length. Barring this, the weld was alright in all other ways. The welder offered to grind the defective portion and redeposit.

However, the inspector demurred, holding that repair is not permitted during a welder qualification.

On another occasion, during a welder’s qualification for strip cladding with SAW process, the bead appearance came out skewed, that is, not of uniform height. Slightly bumpy at one end, and tapered at the other end. Besides, dark black spots were visible on the bead surface, which I attributed to subpar preheat, and perhaps a slight over-build up of flux on the weld.

The welder offered to grind off the entire bead, and re-lay it. The authorised inspector showed disagreement.

There may happen such occurrences during performance qualifications wherein a defect may have occurred on the weld not attributable to welder skill, and might have happened due to a stray incident. This gives rise to the question, does Section IX permit repair during the course of qualification? Does Section IX prohibit such repairs?

The answer to this is that Code does not address this subject. It is left to the judgement of the authority inspecting the qualification. In any case, Code does not cover each and every aspect of welding qualifications. It only tells the minimum requirements that need to be fulfilled.

In my opinion, such repairs in the course of qualification should not be permitted, barring of course some light inter-pass brushing etc.

Welder Qualification For FCAW Process

A Welder Has Been Qualified Through Semi-Automatic GMAW Process. Does This Qualify Him For FCAW Process Too?

The essential variables given in QW 355 are meant both for semi-automatic GMAW process and for FCAW process as well. This is made clear in the title of the table QW 355 itself. This means that the essential variables for both processes are same.

As per Section IX, a welder qualified with a coupon welded with GMAW process is qualified for welding with FCAW process. The reverse is true too. That is, a welder qualified with FCAW is qualified for GMAW too. This understanding has been made clear on more than one occasion by ASME, through Interpretations.

A few related Interpretation numbers are IX-10-03, IX-86-46, etc., these Interpretations can be found here. Just enter the Interpretation number in the appropriate column.

So these were some of the welder performance qualification faqs that one generally comes across. Please do let me know your thoughts on the subject, in the comments section below.

See More:

Welder Performance Qualification As Per ASME Section IX

Qualification Of Welding Materials For Class 1 Nuclear Components

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