By 5mwelder
Date 02-18-2014 04:51
Edited 02-18-2014 04:56
When qualifying a welder to API 1104, can a different grade of pipe be substituted for what is listed on the weld procedure being used for welder qualification. I understand that pipe grade is not a variable for Welder Performance testing, and there wont be any tensile test done, only root bends and nicks.
Say that the WPS list X-65 and the company wants to use X-52, would that be permissible, for welder qualification?
Perhaps I am wrong, but I believe that no matter what, the welder has to test to the given weld procedure to the T, including rod groups, pipe diameters, direction, Amps, Voltage, Travel speed, and PIPE GRADE. If it lists X-65 only, then that is what needs to be used to test the welder, other wise, the company needs to use a WPS for X-52 to test the welder.
Once the welder qualifies to a procedure then he would be able to weld different grades of pipe, given that there is a WPS that covers that particular pipe grade.
Would like to know if I am wrong in what I am thinking and have someone else's input on this subject. Thank you
I have a tendency to agree with you thus far. ASME IX has specific language to allow exceptions to the WPS for materials for performance quals. API to my knowledge does not. Unfortunately.
API 1104 20th Ed. Section 6.2.1 and 6.3.1......."using qualified procedures".
If that's alright, why test the welder at all? Just pencil whip it. I'm sure they've welded on pipeline before. Right? Barring any legal issues you could always track back to a qualified procedure. It wasn't necessarily followed but it was on the job site...maybe.
6.1 GENERAL
The purpose of the welder qualiÞcation test is to determine
the ability of welders to make sound butt or Þllet welds using
previously qualiÞed procedures.
6.2 SINGLE QUALIFICATION
6.2.1 General
Changes in the essential variables described in 6.2.2
require requaliÞcation of the welder.
The weld shall be acceptable if it meets the requirements of
6.4 and either 6.5 or 6.6.
6.2.2 Scope
a. A change from one welding processes to another welding
process or combination of processes, as follows:
1. A change from one welding process to a different
welding process; or
2. A change in the combination of welding processes,
unless the welder has qualiÞed on separate qualiÞcation
tests, using each of the welding processes that are to be
used for the combination of welding processes.
b. A change in the direction of welding from vertical uphill
to vertical downhill or vice versa.
c. A change of Þller-metal classiÞcation from Group 1 or 2
to Group 3, or from Group 3 to Group 1 or 2 (see Table 1).
d. A change from one outside-diameter group to another.
These groups are deÞned as follows:
1. Outside diameter less than 2.375 in. (60.3 mm).
2. Outside diameter from 2.375 in. (60.3 mm) through
12.750 in. (323.9 mm).
3. Outside diameter greater than 12.750 in. (323.9 mm).
e. A change from one wall-thickness group to another. These
groups are deÞned as follows:
1. Nominal pipe wall thickness less than 0.188 in.
(4.8 mm).
2. Nominal pipe wall thickness from 0.188 in. (4.8 mm)
through 0.750 in. (19.1 mm).
3. Nominal pipe wall thickness greater than 0.750 in.
(19.1 mm).
f. A change in position from that for which the welder has
already qualiÞed (for example, a change from rolled to Þxed
or a change from vertical to horizontal or vice versa). A
welder who successfully passes a butt-weld qualiÞcation test
in the Þxed position with the axis inclined 45¡ from the horizontal
plane shall be qualiÞed to do butt welds and lap Þllet
welds in all positions.
g. A change in the joint design (for example, the elimination
of a backing strip or a change from V bevel to U bevel).
5mwelder,
I don't have the 20th edition so the above info might not be 100% accurate. Neither am I an expert on API 1104 but I don't see pipe grade as an essential variable listed it 6.2.2.
IMO, given the purpose of the welder qualification, to determine the welders ability to make sound welds and no mention of pipe grade, it is acceptable to test to a different grade.
I'm not saying that you are wrong...I just don't see pipe grade change as a reason to not proceed with the welder qualification. Obviously, a major change would be an issue but both grades mentioned are similar and intended for the petroleum industry.
X52-52ksi/66ksi Yield/Tensile and X65-65ksi/77ksi Yield/Tensile.
The key here is "using qualified procedures"
Essential variables for procedure qualification comes into play. Irrelevant of whether material grade effects welder qualification, it does apply to procedure qualification, selection and usage. Again, using API 1104 as the qualifying document and forgetting other codes/standards/experiences. If the procedure was not qualified to X52 material, how could one test the welder using X52 materials when no qualified procedure was present or available...which seems to be the case in this situation. Has it been done before? Absolutely. Does it meet requirements to API 1104? Insert interpretation here. Not all interpretations are actually valid however.
By swsweld 
Date 02-19-2014 21:30
Edited 02-19-2014 21:59
To me, it depends on how the "qualified procedure" is written. API 5L X65 and X52 are both in the S-1 Group in ASME B31.3 Table A1. I know that's ASME...not API. The API groupings are addressed below.
If the WPS list ONLY X65 then I concede the point that the Welder Qualification should be with the specified material.
The WPS was qualified with X65, the higher grade as required in 5.3.2.2. If the WPS list another group to include X52 then the Welder Performance could be done using X52 but that doesn't seem to be the case.
Materials being an essential variable for procedure qualification but not welder qualification still leaves some wiggle room if the procedure was qualified to the higher grade...IMHO.
PROCEDURE QUALIFICATION
5.3.2.2 Pipe and Fitting Materials
The materials to which the procedure applies shall be identi-
Þed. API SpeciÞcation 5L pipe, as well as materials that conform
to acceptable ASTM speciÞcations, may be grouped
(see 5.4.2.2), provided that the qualiÞcation test is made on the
material with the highest speciÞed minimum yield strength in
the group.
5.4 ESSENTIAL VARIABLES
5.4.2.2 Base Material
A change in base material constitutes an essential variable.
When welding materials of two separate material groups, the
procedure for the higher strength group shall be used. For the
purposes of this standard, all materials shall be grouped
as follows:
a. SpeciÞed minimum yield strength less than or equal to
42,000 psi (290 MPa).
b. SpeciÞed minimum yield strength greater than 42,000 psi
(290 MPa) but less than 65,000 psi (448 MPa).
c. For materials with a speciÞed minimum yield strength
greater than or equal to 65,000 psi (448 MPa), each grade
shall receive a separate qualiÞcation test.
Note: The groupings speciÞed in 5.4.2.2 do not imply that base materials
or Þller metals of different analyses within a group may be indiscriminately
substituted for a material that was used in the qualiÞcation
test without consideration of the compatibility of the base materials
and Þller metals from the standpoint of metallurgical and mechanical
properties and requirements for pre- and post-heat treatment.
API 1104 Section 6.2.1 states explicitly that the welder "shall make the weld using a qualified procedure".
How do you do that when using a material that is not included in the scope of that procedure?
Unless there is language that can be found similar to that in ASME Section IX I think he is stuck with using the procedure qualified materials.
Personally I think its stupid but it is how I read the Standard.
Because the materials are not an essential variable.
I have gone round and round with the pipeline companies over this and they still think if you change from X42 to X52 you have to re test the welders.
Hey, its their nickel. And if I am on it, boys, line up. But the pipeline companies waste lots of $$$ doing things like this.
kahuna,
I think that's little different point. I think it is totally ligit to NOT retest welders. I would agree with you.
We don't retest welders going from X42 to X52. But we do have qualified procedures in place for both.
Were a customer to impose such a requirement I would actually be more than glad to do it. But they would pay for it because they would not be able to show me where in 1104 it says I have to re-qualify welders based upon strength categories.
I would agree with this as well. I think these are different issues though as js pointed out. For the initial qualification using a qualified procedure, if your not going to use applicable material where do you draw the line? Use electrodes not specified even though they're in a similar group (i.e procedure calls for E7010-A1, let welder test out with 5P+). Not preheat (if specified) because it doesn't affect welder qualification? Let them switch polarities if they want?
By 5mwelder
Date 02-20-2014 02:42
Edited 02-20-2014 02:47
My thought process behind this is, that when a WPS is given, then it should be followed within the written essential variables. Also, while testing welders, If they were testing for a job using X-70, but tested with a lower grade such as X-52, or even X-65, then it would not be fair for anyone. You could possibly have a high rate of welders who passed the tests with X-52, then only to fail production X-Rays, due to internal undercutting. (One of the reasons clients will retest welders to each pipe grade of X65 and above).
If WPS had stated X-52 through X-60, then there would be no problem testing to either pipe grades.
I understand that Material grade is not an essential variable for welder qualification, however the welder qualification WPS should still be followed, Only once the test is passed then the welder will be qualified to weld on different grades.
There was several good points brought to this thread. So I thought that I would try to find a solid answer from API.
I sent in a Request for interpretation (RFI) to API
Background; Testing welders with a qualified procedure that is for X-65 pipe, but using X-52 pipe instead.
Question; While giving a Multi Qualification Welder performance test, can a pipe grade, other than what is listed on testing procedure, be permissible?
Reply; In response to your question:
Answer: No. A change in base material constitutes an essential variable and requires a procedure specific for that base material. Base materials are grouped according to API 1104, Section 5.4.2.2. Grade X52 and grade X65 are in different base material groupings and require different qualified procedures.
That is the answer that I got from API. Thanks for all of the input
And that carries more weight than even an engineers answer to an RFI. And especially more than any of our 'opinions'.
Have a Great Day, Brent
5mwelder,
Thanks for the official answer from API.
It was good practice looking up the applicable sections 1104.
I see you did get the correct interpretation from the API. That makes me happy. The thing to remember is that the test is to prove the welder can deposit sound weld metal using a qualified welding procedure. Grade of the material is not an essential variable. X52 pipe would not be included in a procedure qualified for X65 pipe. You do not have to test on the actual pipe diameter that you will ultimately be welding on. Welders have their best shot at making a good welding during the test, nervousness set aside. I have tested and qualified welders who were released from welding only a few days later due to poor welding performance.
Even in the multiple or unlimited qualification for the API 1104 the welder does not have to qualify on the material grade they will actually be welding on. They only have to prove they can deposit sound weld metal in accordance with a qualified welding procedure, both a butt weld and a branch weld. Most of the time I would say this is done on 12" Grade B or X42 for two reasons, cost of material and time involved in testing. I saw in another post concerning the branch-on-run test where a thread indicated that the welder had been qualified with two nick breaks and two bends. I should have commented there (the post was getting rather long) but the requirements are that for the branch requires four nick breaks on the branch. But I have witnessed some strange testing going on in some of the places I have visited as an inspector/auditor.
I have some background (very trusted word of mouth) on the branch-on-run weld requirement if any are interested. I can go back to the branch-on-run post and add an additional explanation there if there is any interest.
By AV
Date 02-04-2018 15:56
See interpretation 1104 - 20 oct 2005 - 1104-I-1123-15.
