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Combination GMAW & FCAW

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I was wondering if you could shed some light on this subject. We have two different processes being used, GMAW and FCAW. The GMAW is used for tacking stiffeners to panels up to 60 feet long the joint configuration is a T joint. The tacks are between 1/8" and 3/16" weld sizes and they vary from 3" to 4" in length about every 18" in between tacks.  The FCAW is then used from a welding gantry, welding over the previous tack welds from the GMAW with the FCAW process with a continuous weld.

D1.1 2010 in table 4.5 PQR Essential Variables. Comparing the processes there are substantial variables. Our thought is to run a PQR using the two processes together on a V groove weld to qualify both processes. GMAW and FCAW using 100% CO2 welding the root pass with GMAW and then the second pass with FCAW mixing the two processes until the groove joint is completed. Clause 4 in table 4.4 groove test figure 4.23 1 G test.

Will this suffice what we're trying to achieve? I appreciate your input on the matter.

Best Regards.
Gabriel M.

Gabriel,
There are a couple ways you could approach this.  First, are PQR's needed?  This should fall under prequalified unless I'm missing something.  If it is, all you'd need to do is write the prequalified WPS using both processes.

If it is not able to be considered prequalified you could do the required PQRs for each process (GMAW & FCAW).  Or, you could combine processes in your PQR's.  A GMAW root would be sufficient, then a FCAW fill and cover.  Don't switch back and forth between processes for the fill and cover, you are qualifying each to a depth (GMAW to about 3/16 and FCAW to the remainder).

Another option might be to qualify these fillet welds using a fillet welded T-Joint just like you do in production.

Keep in mind, all Welders shall be qualified.  If you are using both processes they will require qualification to both processes.

PWC


What Goes In a Visual Inspection Report?

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Hi, Paul,

Could you let me know what information you think should be included in a visual welding inspection report?
I’m seeing a lot about what the inspector should be verifying, but not the actual items that should be in the report.
 I appreciate your help.
  
Best Regards,
 Anthony N.

Good question.  For NDE (nondestructive evaluation) we typically go to our code books to find the correct forms required.  Although using those specific forms isn’t a requirement, they are a great guide to determine what information we need to capture. 
Visual Inspection (VT [visual testing]) is a form of NDE, but I’m not aware of a code supplied form for recording it.  There is no simple form to download and fill out when it comes to VT.
In my day-to-day, I may use a spread sheet, a Word doc, or the old reliable composition note book.  It all depends on my situation.
As for what information to capture? My guidelines are; keep it simple... Let’s assume AWS D1.1 is our code. Sub-Clause 6.9 states, “All welds shall be visually inspected...”  That doesn’t leave a lot of “wiggle-room”.  We know we have to look at all welds.  It also states, “...and shall be acceptable if the criteria of Table 6.1 are satisfied.”  So now we know our acceptance criteria.
At a minimum your visual inspection (VT) report should state:
What was the date of fabrication?
What was the part/print number?
What was the welds location?
What was the acceptance criteria? (i.e.: AWS D1.1:2010 Table 6.1, Statically Loaded)
Did it meet the requirement?
Did anything restrict your inspection? (i.e.: Part was galvanized, Root was lot accessible, Roof decking covered weld face...)
Was it acceptable?
What is the date of inspection?
...and always add your name (legibly), signature and CWI# (if applicable).
Remember, listen to your customer to gage the level of detail requested, but always make the report clear enough so you understand what was written long after the project is complete.
 
Good Luck,
PWC

"Scare a moose, scare a moose, will you do my fan Van Gogh"

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Paul

I find myself rejecting a lot of welds. I don't want to fail them and find out that I misinterpreted something. When there is undercut in small amounts throughout the length of the weld I'm still not clear on what they mean by "...in two inches up to 12 inches..." (AWS-D1.1, Table 6.1(7))  so I find myself pretty much disregarding the 1/32nd undercut rule, unless the weld is less than 2 inches long. And I just use 1/16.
David N.

All right, here we go...
Table 6.1 (7), Undercut:
"shall not exceed 1/32 in. except...Shall not exceed 1/16 in. for more than 2 in. in 12 in."(artistic liberties taken liberally)
So, undercut that is not more than 1/32" is acceptable. Period!  Also, undercut greater than 1/32" that does not exceed 1/16" and it's accumulated length comes to 2" or less is also acceptable.
Example 1: You're looking at a 3" weld. It's got 1/16" of undercut (depth) for 2" of its length. It's acceptable.
Example 2: A 3" weld is part of a 3 on 6 intermittent fillet weld. Imagine 3 of those fall with in 12". One 3" weld has undercut and the undercut is 1/16" (depth) for 3/4" (length). Another 3" weld is undercut  at 2 places. The undercut is 1/16" deep for 3/4" and again for 1/2"‎ of length.  The last 3" weld has 1/32" for its entire length. These 3 welds falling with in the same 12" of a joint length would be acceptable (Total length of undercut greater than 1/32" deep equals 2").
Now my head hurts.
PWC

Ahh... finally it makes sense.  Now I'll have to read it until it's burned into my brain.  I never put it together that they were talking about intermittent welds.  I wonder if everyone else assumed I understood that, or if they don't know either.
Thank you!  You have saved me much self-doubt!
David N.

No, no, no... I simply used intermittent welds as an example. If you had a weld that was 8" long, the same rules would apply.If it had undercut its entire length that did not exceed 1/32"‎ it's acceptable.  Along that same weld, at one location the undercut is 1/16" deep for 1/4", then 1/16" deep for 1/2", then again for 1", then again for 1/4", that weld would still be acceptable. (as long as the individual undercuts greater than 1/32" but not over 1/16" do not total more then 2" of length in any 12")
Again, my head hurts.
PWC

Holy crap! I understand even better now! So the length they are talking about is how far along the weld the undercut runs.  That is the biggest part I wasn't grasping before. That's so simple... And now quite embarrassing. No wonder nobody could explain it to me, it should have been obvious. Every time I read about the two inches, I was thinking it had something to do with the length weld, not the length of the undercut portion.

I guess I am finding the downfall in studying by myself! I couldn't get past my initial understanding. Kind of like when you learn the words to a song incorrectly, and even after you find out the correct words, you still sing them wrong out of habit... Okay, fine. Maybe it's nothing like that!
David N.

That is Exactly what it's like.
"Scare a moose, scare a moose, will you do my fan Van Gogh"
PWC

Essential and non-Essential Variables... they can make ya nuts

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Dear sirs, I have a doubt about WPS (Weld Procedure Specification) by API 1104 - 2013. For me is not clear if “is outside diameter an essential variable in wps api 1104”, because of in 5.3.2.4 say “The ranges of specified outside diameters (ODs) and specified wall thicknesses over which the procedure is applicable shall be identified. Groupings are shown in 6.2.2 d) and 6.2.2 e).”, and in 5.4 is not included as an Essential Variables.
Thanks regards
Rafael

Rafael,
Essential and non-Essential Variables... they can make ya nuts.
We're often familiar with Essential Variable (those variables that, once changed beyond specific limits, require re-qualification of a WPS.), but what is a non-Essential Variable?
These variables may not show up in a table or list telling us what are allowable variations but they are equally important when writing your WPS.  I often find them left off of WPS's and that only leads to confusion when customers, inspectors or Welders try and interpret or apply your WPS.
When a non-Essential Variable is changed no additional testing is required, but the WPS needs to be changed to reflect the new variable.
Some examples would be:
     *Base materials - Although base material Groups can be Essential, the individual material types are considered non-Essential.  You completed a WPS of a specific material and it qualified you to within a Group.  If you want to change (or develop new) your WPS to reflect a different material within the Group
it is simply a matter of paperwork.
     *Joint Type - Once I qualify a specific joint type that test qualifies a large number of joint types.  I only need to change my paperwork to reflect a different joint design.  (You can now see where a single PQR can qualify a large number of WPS's.)
     *Electrode extension - As a Welder I can vary current by as much as 50 amps by simply changing my stick-out.
     *Electrode type - (GTAW)
     *Technique - Can I weave? Can I whip? Am I allowed to oscillate?  All should be addressed.
It surprised me, that Diameter is not be an Essential Variable per Section 5.4 of API-1104.  But listing it on the WPS is required.
“5.3 Welding Procedure Specification
5.3.1 General
The welding procedure specification shall include the information specified in 5.3.2 where applicable.”
So thickness IS an Essential Variable but Diameter is considered a non-Essential Variable.  Both must be listed on the WPS.
Good Question, Good Luck,
PWC

"Common Sense" not always That common

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Hello Paul,
I was hired into the quality group at a company  alongside three other CWI's last October.  I'd been asked to do a lot of paperwork type activities until this last July when they needed
that fourth CWI on the floor.
I seem to have put the floor into shock... for example: for inspecting parts to the tolerances on the drawing and writing a nonconformance when it's out of that tolerance range.  The other inspectors had been trying to convince me to apply "common sense" to let the parts through anyway, even if that meant the associated paperwork doesn't line up with what the physical part is.  I'm still the same person I was when I came through the code clinic, you can guess how the workplace has become increasingly hostile towards me yet again.

I write to ask two quick questions to verify if my thought process is correct if you have a moment:

1. Detailed vs. fit-up tolerances.  The code and chatter on the AWS forum eludes to fit-up tolerances applying to the as detailed one.  So if detailed gave me +10 degrees, fit-up would give an additional 10 degrees - stacking the two together.  I thought I distinctly remembered from the code clinic that the tolerances do not stack, but that both apply to the original, 45 degrees for example.  So the max. would be 55 degrees end of story.  I am not able to find the support in the code for that and was hoping to double check my memory on that.

2. Starts and stops of intermittent welds.  It seems that the D1.1 exception for filling a crater to the full cross section outside of the intermittent area has been taken to the level that the code doesn't apply outside of the intermittent length.  Doesn't it still say we should have complete fusion, and smooth transitions - not worms at the start and stop of those?

Just thought I would check in to make sure I'm not getting off base here.
Thanks,

Jessica P

Hey Jessica,

Let me get right to answering your questions...

When it comes to “AS Fit-up” vs “As Detailed” tolerances, during the seminar I will always emphasize, “For the purpose of this test, do not stack the tolerances.”  I’ll then go on to say, that may happen in life, but do not do it for the purpose of this test.” CWI’s should never use the “As Detailed” tolerances... only the engineer/designer of the part/joint should.  Let me give you some examples:

1.)  A Designer/Engineer calls out a B-U2a with a 45 deg Groove angle.  The shop floor/Welder/CWI can apply the “As Fit-up” tolerances ONLY and the Groove angle can now range from 40-55 degrees.

2.)  A Designer/Engineer calls out a B-U2a with a 55 deg Groove angle (he/she applied the “As Detailed” tolerances).  The shop floor/Welder/CWI can apply the “As Fit-up” tolerances ONLY and the Groove angle can now range from 50-65 degrees.

3.)  A welding symbol calls for a 30 degree V-Groove on a Butt Joint.  The shop floor/Welder/CWI can apply the “As Fit-up” tolerances ONLY and the Groove angle can now range from 25-40 degrees.

4.)  A welding symbol calls for a 35 degree V-Groove on a Butt Joint (engineer applied the “As Detailed” tolerances).  The shop floor/Welder/CWI can apply the “As Fit-up” tolerances ONLY and the Groove angle can now range from 30-45 degrees.
All those scenarios are perfectly acceptable for that joint type.  The Designer/Engineer has one type tolerance they design within, and the shop floor/Welder/CWI have a different tolerance they work within.

Now let me give you some scenarios that DO NOT WORK:

5.)  A Designer/Engineer calls out a B-U2a with a 45 deg Groove angle.  The shop floor/Welder/CWI applies the “As Detailed” &“As Fit-up” tolerances and the Groove angle now ranges from 40-65 degrees.

6.)  A welding symbol calls for a 30 degree V-Groove on a Butt Joint.  The shop floor/Welder/CWI applies the “As Detailed” & “As Fit-up” tolerances and the Groove angle now ranges from 25-50 degrees.

The shop floor/Welder/CWI should never stack the tolerances on their own.  Again, one set of tolerances is for the Engineer/Designer, another is for the shop floor/Welder/CWI.
Clear as mud, eh?

As for the intermittent fillet weld...
The crater can remain unfilled (weld is undersize) as long as the crater falls outside the required weld length.  All other acceptance criteria have to be met for the entire weld length (including the crater).  So unacceptable contours, unacceptable undercut, unacceptable porosity, cracks, overlap in the crater would still render the weld “Unacceptable”.

As for your work environment...
Working with other CWI’s can, at times, get challenging.  Like Welders, not all have the same skill set.
I took a position once and was over 5 CWI.  In my first week I found that all Welders were qualified with FCAW but 75% of the welding was with GMAW.  I called each into my office to ask about this.  The responses were pretty lame, “That’s what we’ve always done.” “You can’t change things around here.” “There really no difference.”

Don’t Be That Guy/Gal!  Stick to the requirements and intent of the code, and when there’s a disagreement don’t argue, “Put your finger on it”.  Better to have integrity then a stable job (I’m sure some would not agree with that line).  My unstable work history has worked well for me.

I hope that helps.  Hang in there, you know this shit.

PWC

WPS & PQR for Dummies

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Hey Paul,
I'm reading up on the proper procedure and practices for developing a WPS and PQR, my question is, do you know of any resources that give a sort of 'WPS & PQR For Dummies'.
At current I'm reading through section 4 of D1.1, and taking notes as to what is required. The process we'll be qualifying is an in house change (bevel angle, and a slight change of amperage and travel speed.) that will be implemented into production.
From my limited perspective I'll be writing down the proposed values on the PQR, send it out for testing, if it comes back with a passing marks, I'll used that information to create a WPS.
However, on the PQR forms we have here, there is a line for "Governing WPS"...something about your seminar mentioning "Which comes first, WPS, or PQR" comes to mind, however I'm unable to to more than remember that idea.
Any help on the how-to is much appreciated! And also, do you have some sort of donation or fund in your name? I feel guilty asking for your assistance without some way to pay you back. If you've any ideas, let me know!
Thanks again!
Neil

Hey Neil,

WPS & PQR for Dummies… I like that.
You may find AWS-B2.1 helpful (https://pubs.aws.org/p/1245/b21b21m2014-specification-for-welding-procedure-and-performance-qualification).
Start by writing a “Preliminary WPS” (This could be considered a “Governing WPS”).  This isn’t a real, qualified WPS, it is simply a list of what you’d like your final WPS to look like.  Write each of the essential (and non-essential) variables, as you would like to see them.  Then work backwards to figure out what PQR(s) you’ll need to qualify them (notice, it could be several).
Starting with a Preliminary WPS helps keep you on track and keeps you from making the common mistake of finishing all your testing and concluding with an, “Oh Crap!... (insert problem here)”.  Problems like, “I should have used a Group II steel.” Or “I should have dropped the plate temperature to 50 degrees before starting the root pass (or fill pass).” Or “What was I thinking using a 4 in. pipe?” Or “I should have used a square groove.”  You get my drift.
Once you have a Preliminary WPS, break down each variable and ask yourself,  “What do I need to do to achieve that?”
Chances are your finished WPS will have greater ranges than your Preliminary because you’ll be working with real data.

As for your specific need (bevel angle, and a slight change of amperage and travel speed).  You may find that your original PQR already qualified the joint and parameters to within the ranges you are shooting for.  If so, you simply have to revise, or write an additional WPS.  If not, just go through the steps I laid out above.

This line kinda creeps me out, “I'll be writing down the proposed values on the PQR, send it out for testing, if it comes back with a passing marks, I'll used that information to create a WPS”.
That sounds a little, just-throw-it-over-the-wall-ish to me.  Let me break it down…
You’ll be:
• Writing down the proposed values
• Taking them to the Welder/Technician for feedback
• Observing, measuring and documenting as those proposed values are utilized
• Determining visual acceptance
• Sending the weldment out for NDE and destructive testing
• Reviewing the test results for compliance
• Using your collected data to develop a WPS
You have to be the one insuring every step was followed.  You’ll need to wear the welding helmet to insure technique was correct.  You’ll need to insure the final weldment met the acceptance criteria before NDE/Destructive testing.

And finally (and most important) yes, I have a GoQuenchMe campaign that runs continually.  You show up in my part of the country or I show up in yours and you have to buy the first round.  I believe in keeping it simple.

Cheers!
PWC

Pre-Heat & Interpass Temp

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Hey Paul,
From your experience, what is your preference when it comes to measuring the temperature of your PQR's?
At current I have access to 7 different rated tempilstik's, but that doesn't sound like a reasonable arsenal to do the job....or is it?
The IR Pyrometer I have is unreliable at best (as well, no calibration records).
If anything, I'm intrigued by the digital contact pyrometers out on the market. Specifically the Estik looks good, though the 2% tolerance for each displayed value is a bit concerning in the upper limits.
As always, thanks for your insight to age-old questions for us newbies!
Neil

Good questions…
The thing about the Temp Stix is that they are considered the “accepted” method (no controversy), especially when dealing w/Governmental agencies (Army Corp of Eng, DOT…).
Honestly? I use my IR gun to determine which TempilStik to use.  Sounds weird, I know.
If I can prove to myself that my IR gun is accurate (often dependent on surface condition) I’ll use its readings, but if I’m the least bit concerned, I turn to the TempilStik. 
Here’s how I’ll write a PQR:

Pass 1: Greater than 125 / Less than 175
Pass 2: Greater than 175 / Less than 225
Pass 3: Greater than 225 / Less than 300
Pass 4:  Greater than 300 / Less than 500

Kinda messy, but I don’t know a better way to do it and it’s never been questioned.  In fact, when they see the ranges they almost automatically know I used a TempStik and don’t question it.
I use to have a contact pyrometer and would spend a lot of $$$ keeping it calibrated.  After going into biz on my own I simply wrote a calibration procedure that stated “Place probe in ice water (50% crushed ice/50% water) let stand 10 min.  Insure temp reads 32 deg F +/-5%”.  That always worked (right up until I lost it).

Hope that helps.

PWC

WPS from Multiple PQRs?

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Hey Paul,
How does one support a WPS from multiple PQR's?
Neil

I've used multiple PQR's on a single WPS many, many, many times.  When creating a WPS in manufacturing for GMAW I may want the WPS to cover all the electrode diameters (0.035, 0.045, 0.052) and wire feed speed (WFS) ranges that can be run.  A typical ER70S-6 WPS could take me 9 PQRs (3 dial. x 3 WFS ranges).  That was common for me as a Welding Engineer.
Equally…
When I qualify a single PQR I'll write as many WPS's from it as I can.  Example: I qualify a Bevel Groove with a PQR, I'll also write a WPS for a V-Groove, a U- or J-, all the PJP's I can and Fillets.  I try to get as much “Bang For My Buck” as I can.
PWC



Radiograph and IP (off The Facebook)

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James H
I recently had a friends weld get rejected by xray for a concave bead.  Repaired it, reshot it, and it came back rejected for IP.  Two times in this last year I've heard this. Both times, same example. Is it just a bad xray tech or is it a change in the rules today?

Paul W Cameron - CWI
A friend eh?
Let me preface this by saying, "I'm no RT Guy." but, a concave bead in a radiograph could easily mask Incomplete Joint Penetration (IP).
A concave bead will appear darker (because it's thinner) than the base material around it when viewed in a radiograph. Once that concave bead is repaired (adding more weld [making it thicker then base material]) the area that was once dark is now light and any IP would be clearly visible.

Great Question!
PWC
https://www.facebook.com/PaulWCameronCWI

When a Welder Qualifies a Procedure

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Paul,
Specifically, AWS D1.1-2015 4.15.3 Welder an Welding Operator Qualification Through WPS Qualification states. "A welder or welding operator may also be qualified by welding a satisfactory WPS qualification test plate, pipe or tubing that meets the requirements of 4.9 The welder or welding operator is thereby qualified in conformance with 4.15.1 and 4.15.2."

Does this mean if an operator performs the same test as was done on the PQR, but it's only subjected to the Two Side bends, this operator is clear to use this WPS? If so, does an operator need to perform a test for every WPS that they use?
Neil

Neil,
This reference (4.15.3) is only referring to the actual operator that welded the actual PQR test.

Whenever an operator completes a successful PQR test that operator is awarded a Welder Performance Qualification Record (WPQR).  So from a single test plate you will develop 3 (min.) different documents;

  • 1) a Procedure Qualification Record (PQR), 
  • 2) a Weld Procedure Specification (WPS) and 
  • 3) a Welder Performance Qualification Record (WPQR).

The first (PQR) will be a record of the actual parameters and acceptable results from the visual, destructive & nondestructive testing.  The second (WPS) will use the PQR data and Tables 4.1, 4.2 (or 4.3 & 4.4 if applicable), Table 4.5 (4.6 or 4.7 if applicable) and Table 4.8 to determine the ranges qualified and layout an actual procedure for welding.  The third (WPQR) will use the PQR data and Tables 4.10, 4.11 & 4.12 to determine the ranges for Welder qualification.

So to summarize, you have the same group of data, but you are developing 2 completely different documents from it.  One for the process and one for the person.  You end up with these funky conditions where a Welder is qualified to do far more then the procedure allows.

Nothing wrong with that.  Even though the Welder is “over-qualified” his limiting factor is that his welding needs to be done to a Weld Procedure Specification, so additional WPS’s would need to be developed for that Welder to use these additional qualifications.

For all additional Welders the PQR (Figure 4.6 & 4.7) and Welder/Operator (Figures 4.16, 4.17, 4.19, 4.20 or 4.21) test plates are different.  You would have to review those figures to determine what is appropriate.  A single tests performed by the Welder/Operator typically will qualify them to weld with multiple WPS’s.  Once a Welder/Operator completes a test, Tables 4.10, 4.11 & 4.12 would be used to determine if additional testing is needed.

PWC

“The only Welder that hasn’t failed a Welder Test is the one that hasn’t been a Welder very long.” - Roger "Bud" Malley

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Paul
I remember you saying that if we had a question about something to just ask.  My question is about welder recertification.  The owner of the place where I work wants me to come up with a “welder recertification process” that includes two 3/8 plate test, one aluminum and one steel, send them out and have them tested.  With 24 welders, think that this would be very costly to do on an annual basis.  I’ve contacted our external CWI for information and he has never herd of doing that other that staying current with continuity.  I was wondering if you have any information on this subject that would help me down that road?  Any information would be greatly appreciated.
Joey D.

Joey,
I like your question.  Sounds like the boss wants to go above and beyond the code requirements (or, he doesn’t understand them), nothing wrong with that, but here’s some of the problems you’ll encounter…

Our first objective is to meet the code requirements. Going beyond them is great, but the first objective has to be to meet them.

I’ve been in many environments where going beyond the code requirements was somebodies dream (never mine) forced onto me.  I have also found that often, the job of the CWI is to protect the Boss from himself.  Adding additional requirements can be a good way of maintaining skill levels and quality, but they will also, always increase drama & cost.

The Canadian Welding Bureau (CWB) will require that CWB Certified Welders re-test every 2 years.  I have found, working in CWB shops that skill levels are easier to maintain.  I always attributed that to the testing requirement.  But maintaining that program is expensive, and when times get tight it is one of the first things looked at to drop.

I have also worked with companies who have used additional testing requirements as a way of maintaining Welder Continuity (a requirement under AWS-D1.1), but these programs have been bulky and expensive and as an auditor it would take me about 10 minutes of snooping to find holes in the program.  In your email you mentioned this annual testing as possibly benefiting Welder Continuity.  There is your first hole.  Logs need to be updated every 6 months and your testing was every 12 months.  It wouldn’t take a lot of digging for me to find a Welder with an out-of-date log.

If you develop an annual testing program you will need to answer the question, “What happens to the Welder who fails an annual test?” That needs to be known before you implement the requirement.

My Uncle (who me & my family considered the greatest Welder who ever lived) once told me,“The only Welder that hasn’t failed a Welder Test is the one that hasn’t been a Welder very long.”
What happens to your Welder that fails (and many will)?  He can’t fail the test and then go back out on the line as a Welder, right?  What about the work he was doing just prior to testing?  Isn’t that called into question?

You can always get those who fail your testing back up to speed with training and evaluation.  It’s been my experience that they don’t loose their skill, they loose their eyes.  Ol’ Welders that have been doing what they do for ever can make perfectly acceptable welds day in and day out, even as their eye sight deteriorates. But give that Ol’ Welder a qualification test (which is almost always different then their day-to-day) and they’ll struggle.  Often, to see.

With todays aging Welder Workforce I have issued “Cheaters” (reading glasses for welding helmets) at 4 of the fabricators I served as Weld Engineer for.

Again, you have to be clear on how you’ll handle these situations before they happen.  I had one Boss that commanded that, “If they fail the test we let them go.”  First Welder to fail was in his 60’s and had been at the company over 30 years (He didn’t get fired.  I worked with him, got him all “Cheatered-Up” and he was back doing what he knew and seeing what he’d forgot.).

I guess my point is, when we attempt to exceed the requirements we build cost and “drama” which seems to escalate to an unhealthy level and then suddenly the program is dropped and we are at risk of not complying to the code, our first objective.

There ya go, Ask me the time and I build ya a watch.
Good Luck,
PWC

What's With Weave Width? (Woah!)

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Good morning Paul,
I have a question for you.
When welding (1/8") E7018 welding rods, what's the maximum width for stringers and for weaving?  I've heard different answers but can't find anything in the D1.1 Structural Code.
Thanks and have a good day!
Ivan A.

Ivan,
For the process you mentioned, SMAW (E7018), you will not find many restrictions on weave/oscillation width. Table 3.6 in Clause 3 - "Prequalification of WPS's" limits the maximum size of single pass fillet welds to somewhere between 5/16" and 1/2" depending on the position.  That would be a limitation on weave width.  Table 4.6 in Clause 4 - "Qualification" would also limit weave/oscillation width in Charpy V-Notch Testing (CVN) applications by limiting heat input and weld metal volume (see: Electrical Characteristics 9).  Travel Speed plays a key role in both those calculations and weave width has a direct impact on travel speed (the wider the weave, the slower the weld progression, or travel).
With other processes (GMAW, FCAW...) weave width would be governed by the Weld Size and "Split Layer" limitations of Table 3.6, the travel speed (see: 19) limitations of Table 4.5, and the Heat Input/Volume (9) limitations of Table 4.6
Over the years as the "Weld Engineer" on specific projects I've come up with weave width limitations that I have found to work in my applications.  They were not limitations listed on a Weld Procedure Specification (WPS) because of a code requirement, they were listed on the WPS because of the "Engineers" requirement (mine).
I'm sure you came looking for a "hard" number you could use to determine weave or oscillation width.  But that is a number that you would need to calculate given your specific requirements.
PWC


How Many Weld Passes?

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What determines how many passes you need to make? My understanding is the weld needs to be the same profile as base metal.
Tim K.

Tim
There is a lot that goes into determining the number of passes.  First and foremost, you have to review your WPS to see what the minimum or maximum pass number requirements might be.  When the WPS does not specify then you're free to use as many or as few as your skills allow.
Here are some things that will determine number of passes:
*Travel Speed - The higher the travel speed, the lower volume of weld, the more individual passes needed.
*Weave Width or Oscillation - As with Travel, the smaller the weave the lower the volume and the higher the required number of individual beads.
*Joint Configuration - All other parameters the same, a bevel groove will need more passes then a V- groove.
*Electrode Diameter and Wire Feed Speed (WFS) - Again, all other parameters the same, larger diameter electrodes or higher WFS will increase volume per pass and decrease the overall number of passes.

Example:
A 3/8" Welder Qualification plate test completed in the 1G (flat) position might be done in as few as 2 passes, or, in as many as 7 or more.  Either can be perfectly acceptable welds made by a skilled Welder.
That same joint in the 2G (horizontal) position would probably require a minimum of 4 passes and may take as many as 9-10.  Same weld quality, just different Welder technique and comfort level.
Same joint in the 3G (vertical) would typically take a minimum of 3 passes but would be of equal quality if it took 5-6 passes.

Code books typically limit minimum and maximum pass size.  That is dependent on process, heat input requirements, material thickness and position of welding.

I've given 1000's of Welder Qualification tests and I'm almost always asked, "How many passes do I use?" My response is always, no less then 3, and as many as it takes to insure the Groove is full, and has no more then 1/8" of Weld Reinforcement (Crown).  Other then that, you're on your own.

PWC

Makes SENSE

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Hey there Paul,

Had a message sent to me from a former employee, they wanted to share with me that "because I was certified by the AWS through the SENSE program my Level 2 certification (QC11) never expires." 

Was curious if you're ever heard anything like this before?
Neil

Neil,
Correct, when certified through SENSE QC11 it never expires (QC10 expires after 1 year, see 9.1).  Keep in mind, this is certification to a level of education and skills training.

I received my “Degree of Occupational Proficiency – Welding” from Duluth Area Vo-Tech in 1980, it never expired.  It simply was proof that I completed the program.  An employer who understood the Minnesota Education System for “Degree(s) of Occupational Proficiency” understood the minimum requirements. So they understood what they were getting in potential employees (skill-wise anyway).  Like the vast majority of Welders I was never a “Certified” Welder, I was simply a “Welder” who was “qualified” by my company per AWS (or ASME or API…).

QC10 & QC11 were developed to create a standard for Welder Education.  Prior to the SENSE program, I could have a certificate in Welding from my local trade school, but if I moved out of my local school district, Lord knows what it meant. The SENSE program puts a clear, understandable meaning to “Entry Level” and “Advanced Welder”.

An employer is still required to administer a qualification test and maintain a continuity log.  Hiring a Welder out of a SENSE program simply helps the employer understand who they’re hiring.

Don’t get a “SENSE Certified” Welder confused with an “AWS Certified” Welder.  One is certified to a level of education, the other is certified to a Process, Position, Electrode…  The later requires the Certified Welder to maintain continuity through the AWS.

Hope that helps.
PWC

No means No

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Paul,
Here’s a question. I’m certified through the Iron Workers Union and I been welding for almost 19 years. Everywhere I've ever worked they says no welding downhill and if you weld downhill you won't pass the structural test.  When running a vertical weld with 7018 rod is it correct to run a downhill pass before you start your vertical ups on Structural Steel? (This email was in response to welding per AWS D1.1:2015 Structural Code – Steel)
Joshua R.

Joshua,
I guess the short answer is "No".
To do so, you would need a weld procedure (WPS/PQR) that qualifies welding vertical up & down with E7018.  You might struggle to find an electrode manufacturer that would support vertical down with E7018.  We’re required to use electrodes within the manufacturer’s requirements.
You (the Welder) would also need to have taken a vertical up and a vertical down Welder Qualification test with E7018 (or another Low-Hydrogen electrode).  These would be F4 electrodes.  Welding vertically down is often done with F3 electrodes, but a structural test with an F3 (E6010) will not qualify you to weld with an F4 (E7018).
I always say that the pre-qualified section of AWS-D1.1 (Clause 3 – Prequalified Weld Procedure Requirements) is filled with good engineering advice.  My “day job” consists of Ultrasonic Testing (UT) of steel structures.  Often, when I find rejects, I also find that some requirement of Clause 3 was not met. When asked, “What should we do now?” my response is always the same, “Meet the Clause 3 requirements.”  That’s not often a popular response.
Clause 3, wouldn't allow welding vertically down with E7018, so again, my best answer is still, “No”.

Good Luck,
PWC


AWS-CWI's, Who needs 'em?

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Good Morning,
I am very interested in a research article into industry perception of the overall value of the AWS CWI Certification. Many organizations have established training and certification programs internally that applies job scope specific training to inspectors while it seems that the AWS CWI training and exam is too general and wide ranging? Just looking for others opinions on this.
Thank you,
Victor K.


Hi Victor,
Although most codes accept the credentials of a Certified Welding Inspector (CWI) for visual inspection of welds, they DON'T REQUIRE that the Inspector be a CWI.  What they DO REQUIRE is that your Inspectors be qualified and that qualification be documented.  Those are two very important requirements; qualified & documented.  They are the requirements of welding codes that I will find not being adhered to when I'm conducting Fabricator/Manufacturer audits with in-house qualified Inspectors.

In your letter you state, "Many organizations have established training and certification programs internally that applies job scope specific training to inspectors..."  I've worked for many manufacturers and have developed those exact programs, but each program I developed insured that my Inspectors were "qualified" and that qualification was "documented". 

It is common in industry today to claim, "Our Welder is our first Inspector."  That's a great approach, but again, to make that claim, your Welders would be required to be qualified as Inspectors (don't confuse this with qualified as Welders) and their qualifications would need to be documented.

There is a document published by the American Welding Society (AWS) to help you develop that training and documentation; AWS-B5.1, "Specification for the Qualification of Welding Inspectors".  It is a terrific guide for developing a visual Welding Inspector program.  Programs developed by a knowledgeable Welding Inspector/Engineer to AWS-B5.1 would typically be excepted by your customers and/or governing agencies.  I have often found, once I've developed an "in-house" Inspector qualification, it was easier to evaluate employees and determine which inspectors may be ready to take the next step to certification.

It is typically your customers or governing agencies that put the requirement in contract documents that visual Welding Inspectors "shall" be AWS-CWI's (meaning certified to AWS-QC1-"Standard for AWS Certification of Welding Inspectors").  When listed in contract documents there's no "wiggle-room" for alternative qualification programs. 


From my own experience, walking onto a project overseen by an AWS-CWI gives me confidence that the Inspector has a good rounded background in all the different areas Inspectors need to understand.  Those areas include; Process, Code Requirements, Inspection Techniques and Metallurgy.  When I'm asked to be a 3rd party Inspector, and I find myself in a manufacturing environment where Inspectors are trained in-house, I tend to ask a series of questions that help me evaluate the qualifications of the other Inspectors.  I want to feel confident that they understand the requirements and the acceptance criteria for the weldments they inspect.  That is a bad time to find out they don’t, and I'll always ask to see their documentation.

I understand folks believing that Certification to AWS-QC1 (AWS-CWI) can, at times, be over-kill for some inspection requirements.  When an alternative program is developed you must insure that it is developed by an individual with a well-rounded understanding of welding requirements.  The kind of well-rounded understanding you'd typically find in a CWI.

Thanks for your question.
PWC

Become the "Qualification Guru of Choice"

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Hello Paul,

Much like yourself, I am a CWI, CWE, teaching welding classes and following the guidelines of AWS D1.1, Structural Welding Code Steel.
I have purchased a number of the pre-qualified weld procedures from the AWS bookstore that fit the specific circumstances of the most common welding practices used in our area (6010 open root, 7018 fill/cover passes).  These weld procedures are referenced in the area on the WPS for welding procedure.
Students are given a written, step by step procedure with illustrations, dimensions and weld parameters for the fit-up and welding of their test plates. Each section must be followed by the students, and signed by the Instructors. The guided bend test is performed by a qualified AWS CWI, and the test results are documented by the same Welding Inspector.
My question is: does this weld test constitute a Welding Certification?
W.P.

 My answer is: It does, but will the contractors, manufacturers or company the Welder works for accept it?
AWS D1.1 tells us that Qualification (not “Certification”) is the responsibility of the “Contractor”.  They can “farm” the work of qualifying a welder out to an educational facility, but the responsibility for that Welder Qualification still falls on the contractor.  That’s the reason contractors give their own welding test regardless of any past qualifications the welding candidate may have.
Setting up a “Certification” program (meaning; backing up a Welders qualification with documentation) in a vocational school isn’t uncommon, but if that program is sold to Welders as a means of becoming “Certified”, you’ve done those Welders a disservice. They could go through your certification process not understanding that their new “Certification” is not valid anywhere.
Setting up that same “Certification” program and making your ”pitch” to area employers as the 3rd party qualification guru of choice would be far more honest and code user friendly.
I spent many years in the welding industry filling the role of Welding Engineer (The person responsible for the qualification of persons and processes), Welder qualification was a messy and time consuming part of my job.  When testing Welders “off the street” I would have a 10/1 pass rate (and then my 1 would fail the piss test).  I would always look to my area technical schools to help me with that, but I found either a welding program that didn’t give me confidence that ALL the requirements of qualification would be adhered to, or the program was nonexistent.
What do I mean by adhered to?:

•  Test plate fit-up met the WPS requirements
•  Test plate position was maintained from start to finish
•  The root pass was visually inspected (by someone who knows the acceptance criteria) and found acceptable
•  Fill passes were randomly monitored
•  The cover pass met the acceptance criteria without requiring repair to do so
•  The bend coupons were from the correct location and same test plate (I use steel stamps)
•  Removal of the backing and weld reinforcement did not fall below the plane of the base material
•  The samples were bent in the correct fixture
•  The person evaluating the bend samples understood the acceptance criteria
Seems simple enough, but at all of the locations I evaluated over my career, one or more (usually many more) of the requirements listed above were not met.
There’s a great need for the service you’re suggesting, just insure you are selling it to the right people.
Good Luck,
PWC

Don't forget to Ping that Weld

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Paul, Got a question for you. I work in the mines, when we are welding something thick our boss tells us to "ping" our welds (excessive chipping /with air-chipper). I've never heard of that before. What’s your input?
Matt

Matt, Your Boss is offering some good advice.  He's actually asking you to peen your weld (I'm sure he says "ping" but this is what he means).
Peening a weld helps reduce what's called "residual stress". When you heat and cool metal it wants to move, but typically the weldment doesn't allow it to move. This builds residual stress in the part.  When residual stress exceeds "Yield Strength" you'll get distortion.  When residual stress exceeds "Tensile Strength" you'll get weldment failure.
Also, welding screws with the materials grain structure (at an atomic level). There are several ways to deal with this. You can Post Weld Heat Treat the weldment: raising it to what's called the transition temperature (Around 1600f), holding it there for some predetermined time and then allowing it to cool in some controlled manner. Or you could apply vibration (vibratory stress relief), vibrating the weldment during welding and shortly thereafter. Or you can peen, hitting the weldment with a peening hammer (or a scaler) to help reduce this stress.
So, what your Boss has you doing is stress relieving each pass to reduce distortion and /or the risk of cracking.  Listen to him.
Good question.
PWC

Find Your Resident Experts

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Hi Paul,
Quick question. Can a CWI write a welding procedure just being a CWI? Or does the company he works for engineering department have to give him the power to?
Unknown
Whomever you are,
Becoming a Certified Welding Inspector (CWI) does not, in-and-of-itself, qualify you as the one who writes Weld Procedures (WPS).  Codes and standards will require that we use “Sound Engineering Judgement” and AWS QC1 - Specification for AWS Certification of Welding Inspectors states“…the CWI shall: 11.2.1 Undertake and perform assignments only when qualified by training, experience, and capability.”
A designation as CWI (or CAWI & SCWI for that matter) does not qualify you for anything outside the scope of visual inspection of welds/welding.  CWI’s come in all shapes and sizes.  Some are Welders considering a career change, some are Engineers, Purchasing Agents, Lawyers, Supervisors or NDE Techs (nondestructive evaluation).  The list is pretty much endless.  All of those backgrounds can make great CWI’s, but none of those backgrounds make the individual an expert in the field of Code Compliance. 
Back in 1993 I was a 3rd shift Welder who dreamed of bigger things.  My employer gave me the opportunity to take the AWS Seminar and CWI Exam.  Shortly after passing the Quality Mgr recruited me to his department for a short-term project of reviewing the companies ASME & AWS WPS’s, PQR’s and Welder Qualification.  Everything I knew about the subject I had just recently learned in a 1 week seminar.  I was nowhere near ready.
After about a week of banging my head, falling asleep reading and making zero progress, that Quality Mgr suggested I enlist the help of others, and that’s what I did.  I found that all throughout our company we had resident expertson some portion of the subject matter. 
Long story short, I mottled through with the help of just about every department in the company and came up with my first Weld Quality Program.  As difficult and frustrating as it was, it was an experience that changed me as a Welder and now, rookie QC inspector (6 months earlier I couldn’t spell QC).
So, none of that actually answers your question… or does it?  Who has, or gives, the power is not the real question here.  Who has the responsibility? is.  The responsibility lies with your Company, and as I found out early in my career, nothing less than the whole company is what it takes.
Good Luck,
PWC

Check That Liner First

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Jason G - Is it acceptable to use .045 wire with a 1/16th contact tip?

Jason,
That's not a "code" question, that's a "weld process" question.
My answer:  You should not have to and there is good reason not to.
The contact tip is the location where current from the electrode lead is going to transfer to the actual electrode (wire).  The larger diameter the hole the wire is passing through, the poorer the transfer.
Of course, a contact tip that is too small a diameter will lead to feed problems, but it would not be common for a contact tip manufacturer to manufacture 0.045 inch diameter contact tips with too small of hole.
You may find yourself experiencing feed or burn-back issues and thinking that increasing tip diameter should solve your problems.  Doing so may help minimize a symptom, but you have not corrected your core problem.
The first place I'd look for solving THIS problem is the gun liner installation.  Gun liners, when installed, need to rest tight against the defuser (part holding the contact tip).  Many mistakes can be made when installing a liner.  One of the biggies I see, is cutting it too short.  A short liner leaves a space between the end of the liner and the back of the defuser.  This space will allow the wire to wobble before entering the contact tip, leading to burn back.  It will also leave space for the buildup of metal shavings which can eventually become the "point of transfer" and lead to burn back.
Someone who does not understand the proper technique for installing a liner will change the liner once problems develop and then not realize they have just set themselves up for failure and frustration.
Always follow the gun manufacturer’s instructions and before cutting it to its final length keep these tips in mind:
1 - Keep the gun as straight as possible.
2 - Mount the gun securely onto the feeder.
3 - Calculate the length the liner needs to extend past the end of the gun (often the gun manufacturer will list this dimension).
4 - **MOST IMPORTANT** Before cutting the liner at that dimension, apply pressure pushing the liner into the gun (you'll find the liner will easily move 1/8" - 3/16"), hold that pressure, measure and cut.
5 - **EQUALLY IMPORTANT** File down the bur formed by cutting.
Give that a try.
PWC
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