PQR/WPS Qualifications

By bfrat Date 05-01-2014 09:08

I have questions concerning the requiremnts of qualifying a PQR and WPS for base metals which are not prequalified in AWS D1.1 table 3.1. It is my understanding after reading the book, section 4 Qualification is the governing section for qualifying base metals with a PQR and WPS. I have a couple things which I just understand.
In table 4.1 to qualify a CJP a 2G position, this qualifies the positon for flat and horizontal and a 3G positon for only a vertical. It also states the same for a PJP and fillets and so on for production pipe and box. In table 4.5 for essential variables, in the general column "a change in position not qualified by tabble 4.1"

Now a welder can test in a 3G positon and be qualified to weld 1G, 2G, & 3G positions along with 1,2 & 3F positions. Why is this or am I not understanding correctly.

So if I was am to qualify different base metals other than what is listed in the AWS D1.1 book table 3.1, it would be best to require a 2G & 3G PQR?? If this is correct, do I need to provide a WPS for each PQR or can both PQR's be listed to 1 WPS with parameter for both?? Now, do I test a welder to the WPS in the 3G positon or does a welder need to test to 2 WPS's 1 in a 3G and 1 in a 2G position.

Last, can I use a prequalified joint listed in the AWS D1.1 code book for base metals which are not listed in table 3.1??

Sorry for all the questions, but I am confused and/or just can not grasp the interpretation of the book.

By 803056

Date 05-02-2014 16:38

You need to hire someone that understands D1.1 or attend a class to get a working knowledge of the basics of qualifying procedures, welders, and how to apply AWD D1.1.

Al

By jwright650 (*****)

Date 05-02-2014 16:57

First: Welcome to the forum. :cool:

At first glance I thought that Al had taken the shortest approach to answering your questions...however while re-reading the post, I found myself agreeing with Al vs trying to answer all of what is being asked.

There are several fundamentals to grasp before trying to qualify anything using Clause 4...mainly the separation of WPS(procedure) and Welder(personnel) qualifications. These are two totally different things so there are Clauses, Tables and Figures just for the qualification each.
Using Clause 3 is great IF you can satisfy ALL of the criteria for your procedure to be considered pre-qualified. If your situation does not meet all of this, then you must go through the testing/qualification process to prove that your WPS(cake recipe) actually works.

Maybe you can break down a few of your questions and we can try to help answer them one at a time. The first post has so many questions and several questions are heading in the wrong direction to begin with, so answers may be difficult to explain in the context in which they were asked.

By bfrat Date 05-02-2014 19:29

Sorry about the confusion and also I think Al is absolutely correct. I do need to seek additional training to understand the complexity of the AWS D1.1 structural code book. I have read clauses 3 & 4 mulitple times and find very interpedtive and confusion at time especially with difficult situations that are not pre-quailified under these clauses.

I thank you for taking the time to resond and would very much ask if you could review some of my question and possibiliy help me. I will try and ask one question at a time. After re reading my first post, I found I was all over the board with my questions and understand your frustration.

The situation starts with a fabricator, which I am trying to get their welders qualified to weld in accordance with AWS D1.1 criteria. This first issue I have is the base metal material, which this fabricator is using is not pre-quailfied material under clause 3 table 3.1. So I now need the fabricator to qualify the base metal before the welders can be tested. The fabricator will need to generate a WPS with a supporting PQR. The question I have is does the fabricator need to qualify the material in mulitiple positions (2G & 3G) or can I have them qualify the material in just the 3G position? Also can the fabricator use a pre-qualified joint listed in clause 3?

Thanks
Ben

By 803056

Date 05-03-2014 13:25 Edited 05-05-2014 00:56

If the fabricator is welding unlisted materials, the materials used in production must be qualified for each combination and thickness range needed for production. To put it a different way, if welding A to A, a test assembly consisting of two pieces of A and A must be welded. If welding A to B, the a test assembly consisting of both A to B must be welded. And if B is welded to B, then you guessed it, a piece of B must be welded to a piece of B.

The fabricator must have WPSs qualified for the positions needed to accomplish the welding under production conditions. If all the work is positioned in the flat position, then that is all that needs to be qualified.

Determining the positions needed for production can be more complicated than one might think. Figures 4.1 and 4.2 can be used to determine the required test positions based on production requirements. Once the production positions are determined, Table 4.1 is used to determine what production positions the WPS is qualified for one the test coupons are welded in the flat, horizontal, vertical, or overhead positions. Point of fact; the test positions for the PQR are flat and level with respect to Earth, i.e., the figures 4.1 and 4.2 are not tolerances to be applied to the position of the test assembly. In the case of the vertical test position, the groove or the fillet is perpendicular to Earth. As with the flat test position, the tolerances of figures 4.1 or 4.2 have no bearing on the position of the test assembly. Likewise, the tolerances of the figures do not apply to the orientation of the horizontal or overhead test positions.

Table 4.1 will give you all the information you need regarding the production positions qualified by the PQR assembly, but it may take a little study to appreciate all the conditions that apply. Be sure to read the footnotes to see if they apply.

Good luck and ask simple question so my simple mind can wrap itself around it.

When it comes to qualifying the welder, with permission of the Owner (the entity that takes legal possession), the welder can be qualified using a prequalified WPS. The intent of welder qualification is simply to verify the welder can deposit a sound weld. The mechanical properties were verified when he WPS is qualified. Now, if the Owner requires the welder to be qualified to a qualified WPS, that's his prerogative, and he must be satisfied. The Owner is in the driver's seat. As they say, "He who holds the gold makes the rules."

Best regards - Al

By Lawrence (*****)

Date 05-21-2014 15:33

Hard to make sense of your meaning.

...identified "vertical position"

Does this mean a 5G or 5F orientation?

(Full Circle) ?

Does this mean you will be doing an uphill progression on part and a down hill progression on the other?

Or will you roll the part?

By 803056

Date 05-21-2014 19:33

That's an interesting question.

Generally the WPS is qualified using vertical uphill progression or vertical downhill progression. There are no provisions to do as you say, weld in a continuous manner, i.e., no starts or stops during the course of making the weld, starting at 6:00 O'clock to 12:00 O'clock and then continuing on to 6:00 O'clock.

My suggestion would be to qualify a WPS using uphill progression so you can extract all the required test samples. Then qualify a separate WPS using downhill progression, again so you can extract all the test samples required. The test samples must be extracted from the welded coupon as shown in clause 4, table 4.2 and figure 4.7.

Once you have both qualified WPSs, you can combine them to do what you have described.

Best regards - Al