Hey All, The company I work for is merging with another and we are reproducing both our quality manual and our WPS catalog. We are a structural steel fab shop and we use all pre-qualified joints. Our existing WPS catalog was last revised in 2008. So my question is according to the D1.1 2010 table 3.8 item #2, do we need to have separate WPS(s) for 1G and 2G and for item #24, do we need to have separate WPS(s) for single bevel, double-bevel, flare bevel, double-flare, and square groove.
I would just like some opinions on what others have done here with the new table. To me it appears we will need separate WPS(s) but soon as I feel like I know what I'm talking about I meet someone wiser and convinces me otherwise. Thanks in advance.
Fabsforlife,
There appears to be a major conflict between Clause 3.6, Table 3.8 and the Commentary .
Initially I thought it would be quite easy to answer your question - now I am completely confused.
The title of Table 3.8 is Prequalified WPS Variables (not Essential Variables ?)
If you go to Item 2 it states "A change in welding position(s)" - note the plural, not position but positions.
My interpretation of that is if you wrote a WPS for Flat and Overhead positions you couldn't use it for a Vertical weld.
This theory appears to be supported by the Note 1 to Table 3.8.
"a A separate WPS shall be required when this variable is changed".
The only items with an "a" are 1 and 25 (nothing to do with position)
Clause 3.6 states "The welding parameters set forth in Table 3.8 shall be specified on the written WPS, and for variables with limits, within the range shown. Changes to the essential variables beyond those permitted by Table 3.8 shall require a new or revised prequalified WPS."
My question is "What are the essential variables ? - all variables listed on Table 3.8, all items identified with an "a" on Table 3.8 or all variables with a limited range noted ?"
Then, to really muddy the waters.
Note 2 of Table 3.8 states " An "X" indicates applicability for the process; a shaded block indicates nonapplicability."
BUT
the Commentary states
C - Table 3.8 Prequalified WPS Variables
An "X" in Table 3.8 indicates that a change in that variable, or a change outside the range indicated for that variable, requires a new prequalified WPS." ??????????
Can anyone help myself and Fabsforlife out with this one ?
Cheers,
Shane
I've never been a good explainer of things, thats why I usually keep my 2 cents to myself.
What the code is trying to say (my opinion) is that to change, for instance, the position (s), all you need to do is add it to the existing WPS. Note the (s) after position, that means singular or plural. If your WPS lists Flat and Horizontal, or just flat, or just horizontal, you can just add Vertical or overhead or both without rewriting your WPS.
To change item 1 or 25, you would need to rewrite your WPS. you could not have a WPS that says "all processes", or "with or without PWHT". for those 2 changes, a new WPS would need to be written.
Hope that helps.
Thanks guys for the feed back it helped a lot. So according to what the commentary is saying and how your explaining it (if I am understanding correctly) we could have a single WPS for fillets covering flat, horizontal and vertical welds and then we could also blanket another WPS covering pre-qualified PJP joints using flare bevel, double flare bevel, single bevel and double bevel in the flat and horizontal positions and still be compliant with Clause 3.
Ok here's another curve ball....For CJP prequalified joints, can we use a single WPS that covers joints using steel backing and joints to be back gouged(non-tubular joints)?
It is obvious upon first glance that some things have definitely changed in Table numbers etc from the 2008 in front of me to the 2010. As I drove my truck today because of snow I don't have my 2010 available.
And I think I remember this discussion coming up after the 2010 came out and that it did change some of the conditions under which one must issue new WPS's. Previously I would have said no. Also, Shane, they may not have caught all the areas in Text, Tables, Figures, and Commentary where changes needed to happen to keep all in agreement. Sometimes it takes a couple of erratta to get it all together.
Have a Great Day, Brent
FabsforLife,
As we are a structural fabricator as well, over the past 6 years since I took over as QA I have found that as AISC, EOR's and others get better information and educated that they won't allow a "blanket" WPS to cover all pre-qualified joints. I had that in the beginning as that was what I was left with form the previous QA. And as I submitted them for projects some would get rejected and sometimes they woulnd't. Finally what I found was that the general "blanket" WPS was just that....to general. It wasn't specific enough to actually do any good to the guys in the shop doing the welding.
Think about all the possible root openings, bevel inclusions, number of passes, volt, and wire feed speed variables. Now take that and make it work for EVERY pre-qualified joint, fillet, PJP and CJP, that's alot of information the guys downstairs in the shop would need to know and answer during an audit if they were asked..what's the allowable root opening of a B-u4a vs a B-U2a and included bevel.
My point I am poorly trying to get across is that technically you MAY be able to have a blanket WPS, but if you want the guys to understand how to set up the machine and perform under the best case scenario, I'd go with individual WPS's not just the blanket one.
just my opinion, good luck
Chris
The code is silent with regards to the need for several WPSs or a single “general” WPS.
The contractor is responsible for the work their employees do. The purpose of the WPS is to provide work instructions to the designers, welders, and the inspectors. It promotes consistency, i.e., it may limit the situation where one welder is doing it this way and another welder is doing it that way.
The WPS has to be developed with the needs of the contractor in mind. The minimum requirements that must be met are stipulated by the applicable code, but simply meeting the minimum requirements may not be sufficient to meet the customer’s expectations. With the WPS in mind, a general WPS may be sufficient when specific instructions are not needed. As an example; if the base metal being joined is plain carbon steel where impact properties are not a requirement, heat input does not need to be closely controlled. A WPS that permits both stringer and weave beads is sufficient to meet the needs of the code and the customer’s requirements. However, if the project involves quenched and tempered steels with impact requirements, heat input must be controlled, and the WPS may have to limit the heat input, thus the technique could restrict the welder to using stringer beads only.
It is important that the individual developing the WPS understand the type of product being produced and the give consideration to the customer’s expectations. A WPS written for a general job shop type facility is going to be very different in the level of detail provided when compared to a production facility where the welder is manufacturing one or two different types of welds. A WPS used by a production welder that is welding hundreds or thousands of the same part has different needs than the welder that is producing parts that may be one-of-a-kind. The WPS written for the production welder may be very specific with regards to the materials being joined and with limited current ranges and travel speeds to promote consistence from one welder to another. The customer expects the parts to look the same even if different welders are making the parts. The welder working in a job shop may be the only welder producing one or several parts. The welds are going to be fairly consistent from one piece to another. The range of parts produced could range from a structural member with end fittings to a snowplow frame. The job shop requires a WPS that meets the code, but it should be general enough that it meets the needs of the welder and the employer by giving the welder the latitude needed to weld a host of parts and materials.
You have to consider customer imposed requirements. In the case of bridge construction, many state DOTs require WPSs for each project and each joint type. The general WPS that is suitable for the job shop is not going to meet the customer’s requirements in that case.
This is why I believe a SWPS purchased from AWS has limited value. The SWPS is not specific enough for many applications. The ranges for groove angles, root openings, current ranges, etc. are so liberal they may not provide the type of instruction needed by many welders or customer expectations. I have a number of customers that have purchased them and found them to be nearly useless for production needs. The SWPS follows the mind set of ASME. I have long said that a WPS written to meet ASME in every respect is the only WPS that complies with the code and cannot be used in production.
Best regards - Al
Al,
Question regarding your hesitant stance on the SWPS being too liberal and thus of limited value... As long as the purchaser of it used it only as his verification of a particular procedure but when writing his own WPS's off of it made the joint restrictions and other variables tighter, actually customizing them to the usage at hand, would they not be beneficial then? Faster and cheaper than going through the process one's self? Would this not meet the need of many smaller fab shops doing structural steel with areas that put them outside a Pre-Approved WPS so they needed either the SWPS or a PQR?
Just curious rather they had any value in that arena or not.
Have a Great Day, Brent
Hello Brent;
There are provisions within the SWPS stating the user can implement additional work instructions that are more restrictive that the SWPS. It also states the user is responsible to verify the SWPS meets the applicable code requirements.
What is the rationale behind using a SWPS as a viable basis of the new WPS? The user has no access to the original PQRs. Issuing additional work instructions is not the same as writing a new WPS. The SWPS is copyrighted, meaning the user cannot cut and paste sections for use in the new WPS.
Is using the SWPS as a basis of writing a WPS any more valid or ethical than using someone else’s PQR? Why is it acceptable for AWS to sell SWPSs, but it is not acceptable for you or me to do the same if we have valid supporting PQRs?
AWS concedes the fact that the SWPS is not applicable in all circumstances. It is up to the licensee to determine if the SWPS is reasonable or appropriate to meet their needs. That of course assumes the applicable code recognizes the SWPS and permits its use. If the individual has the wherewithal to review the SWPS and determine whether it is appropriate for use would for all practical purposes be capable of writing their own WPS.
I support many of AWS’ endeavors, but it doesn’t mean I don’t question some of their activities.
There are many lessons learned when a company qualifies their welding procedure. They are lessons that can be expensive, but reality sets in very quickly when money is spent. Those lessons are not learned when a contractor simply “buys” their WPSs. The importance of the groove angle or the root opening isn’t learned until a sample weld is made. The importance of proper precleaning or interpass cleaning isn’t learned until the contractor tries to omit the cleaning operation and the sample fails the required tests.
As a young welder I saw no purpose in qualifying a welding procedure. After all, I had made hundreds of welds that passed UT and RT. As an inspector, it became very evident that practices I thought were known to everyone were not practiced by everyone. It isn’t until money is spent qualifying and failing the tests do many contractor’s realize the importance of good welding practices. What I learned very quickly as an inspector is common sense isn’t all that common.
How many times in your short career as a CWI have you seen a contractor completely disregard basic concepts of good welding practice? Have you encounter any contractors that tells their welders that it is not necessary to remove slag between passes because it is a multipass electrode? The first time I heard a contractor say it, I thought I heard him incorrectly. Since that first time, I’ve heard it the same thing on several projects by different contractors.
I do agree with a basic premise of ASME on this one point, contractors should be required to demonstrate any proposed welding procedure will produce the required results. In other words I do not agree with the SWPS or the concept of prequalified welding procedures. I do a lot of work in the military sector and while it can be a royal pain the butt, I see the value and sanity in their approach of qualifying a contractor. Until the contractor has actually tried and failed to qualify a WPS they don’t appreciate the basic requirements of making a good weld.
I suppose my cynical view point is the product of thirty years as a CWI. My views and long held beliefs as a welder were quickly shattered when I switched sides and became a welding inspector.
Best regards - Al
Thanks Al. Makes a lot of sense. I know our section has some SWPS's in our library, I'll have to try and get ahold of them and look them over to help me with a couple of things yet on my mind. But overall you answered my question.
Have a Great Day, Brent
Al/Brent,
No comment on my questions (or the original OPs) regarding the discrepancies in the new Table ?
Cheers,
Shane
I don't think either of us has gotten to our 2010 codebooks yet Shane. I'm still in my truck because of the weather up here in Flagstaff. 7500 ft elevation hill country with lots of good snow this year. A part of AZ few people see. Everyone thinks of AZ like we were all Phoenix, Tucson, Yuma, or Bullhead City. Those areas are around 1000 ft elevation. This mornings temperature was barely above 0°F. For you Celsius people that's WAY below freezing. Not as much obviously as ND and other points north, but it is cold.
I may be off this weekend and will have some time to see what I can find.
Have a Great Day, Brent
Hello Brent;
I don't want to beat a dead horse with regards to the SWPS.
The SWPSs from what I understand are based on PQRs that were qualified to ASME Section IX. Section IX is quite different from D1.X code requirements relative to essential variables and the test requirements. Consider the following;
Arc voltage, current, wire feed speed, and travel speed is all considered to be nonessential variables per Section IX. They do not have to be recorded and often are not recorded on the PQR. With that in mind, where do those values come from when the SWPS is written? The ranges listed by the SWPS may or may not be based on test data. We don't know because AWS will not provide them to the licensee.
The acceptance criteria of the guided bend test are more liberal per Section IX.
No RT or UT is required per Section IX before the mechanical tests are performed.
The visual acceptance criteria are nearly nonexistent in Section IX.
The bottom line is a procedure qualified per Section IX simply does not comply with AWS D1.1 or many of the other D1.X structural welding codes. Without access to the supporting PQRs there is no way we can know if the SWPS is supported by PQRs that meet the requirements of AWS structural welding codes.
Best regards - Al
why is ASME so different from AWS, what's the history or should I re-phrase how did it end up that way?
AL
Im hunting out your old posts for guidence haha and I am getting what I am looking for
Jordan
Happy to help. Just remember, I am simply expressing my opinion.
Al
