Where Are The Rules For Asme Ix Weld Repair Procedures

In this commodity we shall discuss the various aspects of a WPS for conveying out weld repair and build upwardly on a component, in accordance with ASME Department 9.

QW 202.iii of Article 2 of Section Nine addresses the use of WPSs qualified on groove welds for repairs in welded joints, and for build upwards on base metals for the purpose of restoration of thickness. It basically says that WPSs qualified on groove welds tin exist used for weld repairs to groove and fillet welds and for weld build-ups with the following provisions:

There is no limitation on the thickness of base metallic or deposited weld metal for fillet welds.

Now, when a WPS qualified on a groove weld has to be used on fillet welds, it tin be used for ALL base metal thicknesses and ALL fillet sizes regardless of this provision in QW 202.three. This has been already permitted in QW 451.4. It is not clear why the authors needed to specify this here.

It would have sufficed if they had merely said: "WPS qualified on groove welds tin be also used for repairing fillet welds."

For weld repairs and build ups in other than fillet welds, the base metal thickness and weld metallic thickness shall be in accordance with QW 451, except in that location need be no upper limit on maximum qualified thickness of base metal if the qualification was done on a base metallic having a thickness of 38 mm or more.

This is pretty self explanatory, and needs no farther description. Let u.s.a. come across in what cases the exemption given in 'b' might be of utilize.

Thickness of Procedure Qualification Coupon For Repairs & Buildups

If you have a qualified procedure which was qualified with a 38 mm thick test coupon, information technology would qualify base metal thicknesses in the range five mm to 200 mm. You would non need the exemption granted in QW 202.3 if your production joint thickness brutal in this range.

If you accept a product joint with T>200 mm that you need to freshly weld (and not just repair), you would exist anyway having a procedure qualification that supports this thickness. Repair besides to such a joint can be made using the existing WPS. So when would the exemption of QW 202.3 be useful?

Well, i tin think of only 1 circumstance. When y'all are required to only perform the weld repair work (the original joint was made elsewhere by some other organization) on parts with T>200 mm, and so the exemption given in QW 202.3 is incomparably useful. Likewise this, it is also useful when you need to do build-ups on parts with T > 200 mm.

At present, permit us examine some other aspects of when we use a WPS for making repair welds.

Representation of Weld Repair Groove On WPS

When we apply a WPS qualified on groove welds for repair to a groove weld, which was already welded with the same WPS, does the WPS demand to be revised to have the figure show the weld repair cavity?

Why should this question arise in the first place? This is because QW 402.1 is a variable as per QW 250, and therefore has to be indicated (correctly) on the WPS. QW 402.1 says that a change in the type of groove (V groove, single bevel etc.) is a non essential variable.

All variables identified in QW 250, whether essential or not-essential, must be addressed on the WPS. Although information technology is a not-essential variable, the actual groove of the weld which is going to be made with a WPS, has to be correctly represented on the WPS.

The groove blueprint at the fourth dimension of making the original joint may have been of one type (say V groove). The cavity developed in preparation of groove for repair in the joint might wait like a 'U' groove. This may prompt the welding engineer to think, is the WPS required to be revised to show the repair cavity thus developed, to serve QW 402.1?

As well, sometimes, overzealous inspectors want everything to exist perfect, and would insist on revision of the WPS to signal the exact image of repair groove.

So, what does Section IX intend regarding this? Does information technology crave revision of the WPS?

This question has been asked to ASME a couple of times, in Interpretations Nine-10-15 and 9-79-72. The commission replied in the negative, meaning that revision of the WPS is not required.

The answer further stated that – "The intent of QW 402.1 is to include or reference in the WPS the groove design employed in preparing the base materials for joining into a weldment. Repairs are considered a part of the welding operations." This settles the matter for adept.

At present, this was about when the WPS used for making the repair is the same one used for making the original weld. Tin can we use a WPS indicating a sure groove design to make repairs in a completed weld that had a different groove design (but the weld is completed now; that is, already welded with some other suitable WPS)?

No. I believe that would be a misrepresentation. This kind of a question has non even so been asked in an Interpretation, then in that location are no references to cite. Although it seems a trivial matter seeing that doing and then would not violate any essential variable, in my opinion it would exist appropriate to use a WPS showing right groove shape. QW 402.1 may be a non-essential variable, it does not hateful an incorrect representation would do.

Now, similar to this line of thinking – consider this. Can a WPS showing a groove weld be used to weld a fillet joint, without revising the WPS to show fillet in the effigy?

Using WPS Showing A Groove For Fillet Welding

A procedure qualified on a groove weld is good plenty to weld any fillet size on a base of operations metallic of any thickness and diameter every bit per QW 451.4, so a groove weld WPS is good enough to weld on a fillet weld.

All the same, can a WPS showing a groove weld be used to weld a fillet joint, without revising the WPS to show fillet in the figure?

The thing of whether the same WPS can be used to weld on a fillet joint is a pertinent one, because, although it does non violate any essential variable, this problem is commonplace, and occurs frequently.

Such a question has been officially asked to ASME likewise, who have replied to it through an Interpretation. The Interpretation number is IX-78-x (qs 2).

The respond said that the WPS showing the sketch of a groove weld need not be revised to show a fillet weld when this WPS is used to make a fillet weld. The diction used stated that "The variable QW 402.1 refers to a alter in groove weld joint design and therefore does non apply to fillet welds."

The answer is undoubtedly truthful to the wording of QW 402.one. QW 402.i only talks about groove, non fillet. Nonetheless, the reply is a bit of disappointment to purists, including this author. Using a WPS showing a groove joint for a fillet joint is clearly a misrepresentation.

This Interpretation was issued in 1978, one hopes that the committee would have revised its agreement of the matter. Perhaps the QW 402.1 should exist amended equally "A change in the type of groove (Vee-groove, U-groove, single-bevel, double-bevel, etc), or a change from groove to fillet or fillet to groove. Correct joint configuration shall be represented on the production WPS."

There is another interesting question that comes to listen, regarding the thing of repairs.

Weld Repair With A Dissimilar Procedure

Suppose that a PQR has been qualified using a combination of GTAW (at the root) and SMAW in the test coupon. Using this PQR, a articulation has been welded with GTAW (at the root) and SMAW. Is it permissible to carry out repairs in the SMAW welded portion of the joint using GTAW procedure?

Consider some other version of this. There exist two different PQRs, having all essential and non-essential variables as identical to each other, except that 1 PQR has been welded with GTAW, and another with SMAW. Is it permissible to carry out repairs with GTAW, in a joint welded with SMAW, in the context of these ii PQRs? Or, vice-versa?

Permit usa reword the question one more time. Is it permissible to bear out repair in an already welded joint, with a procedure different from the original procedure used for welding the joint? Assume that the chemical composition of the weld deposited past both the processes is same.

This question has non been addressed in Section 9. So, ane has to take refuge of the Interpretations database, to understand the Committee's intent regarding this. A recent Interpretation, 9-17-29, asked such a question, as described above. The question is reproduced below:

"Background: A joint is welded using a WPS qualified with the GTAW (with the add-on of filler metal) and SMAW processes.

Question: Is it permissible to use the GTAW process, with the addition of filler metallic and not exceeding the maximum qualified deposited thickness, to brand repairs to the SMAW deposit?"

The reply given in the Estimation is a 'yes'. This establishes that such repairs are allowed.

And so this was all about how to reckon a WPS for doing repairs and build ups, in compliance with ASME Section Nine. Do leave your thoughts in the comments section below.

See More than:

Welder Qualification For Corrosion Resistant Overlay