Tuesday, December 29, 2015

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

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  It wouldn’t take a lot of digging for me to find a Welder with an out-of-date log.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

When a Welder Qualifies a Procedure

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

Wednesday, November 4, 2015

Radiograph and IP (off The Facebook)

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

WPS from Multiple PQRs?

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


Wednesday, October 28, 2015

Pre-Heat & Interpass Temp

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

Tuesday, September 29, 2015

WPS & PQR for Dummies

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

Wednesday, September 9, 2015

"Common Sense" not always That common

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

Friday, August 7, 2015

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

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

Tuesday, August 4, 2015

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

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

Thursday, June 18, 2015

What Goes In a Visual Inspection Report?

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

Wednesday, June 10, 2015

Combination GMAW & FCAW

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

Monday, February 9, 2015

Preheat and Toe Cracks, Sounds Painful!

We have been welding on a coupler ladder assembly for an ATB. (Articulated tug barge) It veries in thickness from 3"-1/2" up to 9" thick. The coupler ladder is structural casting ASTM A148-90-60 (Ce= 0.69 Pcm= 0.38) and is being welded to ABS Grade A 1"-1/2" plate and also ABS AH36 3/4" plate. The current WPS is for FCAW it states to use filler metal AWS Specification: A5.20 and AWS Classification: E71T-1CDH8 and to preheat to 300* F. We are having some cracking problems on the weld toe to the cast parent metal. On some of the research that I did it states to use an E81T1-Ni1C wire and to preheat to 400*F. In clause 3 of AWS D1.1 2010 on 3.5.1 base metal / thickness combination. (base on the category and thickness) shall be the highest of these minimum preheats. Would you suggest to increase the preheat to 400* F and use the E81T1 electrode?

Best Regards.
Gabriel M.

The 70ksi electrode should work and the 300 degree preheat should be sufficient. You should have a PQR that was used to qualify these materials. If you do not then you should start there.
My experience with preheat...
When a 300 degree preheat is required keep in mind that the measurement to deturmine if the preheat's been met would be a minimum of 3 inches from the weld. That's 3 inches or the thickness of the material, which ever is more. You mentioned 9 inch material. That preheat would need to be measured 9 inches from the weld.
With toe cracks in high strength material (that A148 is a Class 3) I would suspect preheat and more then that, I would suspect a preheat that is not being applied the full material thickness distance.
PWC

Saturday, January 10, 2015

Those Canucks take their welding seriously

Paul,
I know what you're thinking, another early Saturday morning question.
I've been looking at the requirements of obtaining a CWB inspector certification. Am I seeing this correctly? A CWB inspector can apply for a CWI by reciprocity by nothing more than an application and fees. But a CWI who wants to be a CWB, in this case a level 2, would fill out the application, pay fees, and still have to take an exam?
Doesn't strike me as "equivalent" or fair.
Tim C. CWI, CWE
Level II VT, PT, MT, UTT

Tim,
Your assessment is correct.   For a CWB to apply for a CWI it’s just a fee and some paperwork.  For a CWI to apply for a CWB it’s a test.  Those Canucks take their welding seriously.
I was the Quality Manager in a pole manufacturing company that was CWB Certified.  Every 6 months I had to hire a CWB engineer to audit my organization (and it was an in-depth look at our welding).  There were a lot of hoops to jump through, but if we wanted to sell power-line poles in Canada it was a requirement.
I was also a contract CWI for a boss that was Canadian.  Anytime I mentioned my past work as a Welding Engineer he would go ballistic.  Calling yourself a Welding Engineer in Canada means you’ve met specific requirements in education and testing and if you referred to yourself as a Welding Engineer without meeting those requirements you could go to jail.
Some of the things I liked about working in a CWB shop: 1.) Welders had to retake their Welder Qualification Tests every 2 years.  I believe that helped maintain weld quality in our shop. 2.) Welder Qualifications were given using a Bevel Groove.  The first pass was a Fillet Weld of a specific size up against that square edge of the Bevel Groove.  The fillet had to have a restart in it. The location of the restart was marked, and 1 of the 3 required bend coupons had to contain that restart.
One of the things I didn’t like was that they consider FCAW and GMAW with a Metal-Cored wire (MCAW) the same process (for welder qualification purposes).  The Welding Engineer in me (said quietly so as not to be heard across the MN/Canadian border) sees these processes as requiring different skills.
When working in a shop that requires compliance to CWB and AWS this FCAW/MCAW thing reeks havoc.  In fact, when I showed up for my first week at this pole shop I learned that All of the Welders took a FCAW test to get their job, but the shop ran about a 50/50 mix of FCAW and GMAW using Metal-Core.  From a CWB perspective this was no “Biggie”, but from an AWS perspective (which was about 90% of what they did) no Welders were qualified for GMAW (and not one of the 4 CWI’s that worked there seemed concerned).  What a mess!
The way I turned that around was by using the CWB 2yr retesting requirement.  I gave MCAW tests, had them evaluated by the CWB to Canadian standards and evaluated them myself as a CWI to AWS standards.  At 6 month intervals, over a 2 year period, those Welder Qualifications were brought up to speed.
If I was an independent contract CWI I’d probably pursue the CWB route, but if you work in a shop that’s considering bringing in CWB work then CWB/CWI reciprocity is the least of your worries.
PWC

Saturday, January 3, 2015

Fillet Welds on Corner Joints

Hello,
I have a question regarding D1.1 code.
My question is regarding the corner joints in the plates encompassing the columns. They are calling them Fillet welds, yet there is not any faying surface. D1.1 says a fillet can have up to 3/16ths misalignment (with certain stipulations) which is effectively is making the joint an open root CJP.
They are using a ceramic backing that (desired because of the tight fit around the square column plus the misalignment) is reducing the theoretical throat greatly. Now they are having substantial issues with cracking threw the throat, which isnt surprising.
My issue though is with the joint design; Im inclined to say it is not a fillet weld, but I cannot find a code reference to support that claim. And I cannot find a prequalified wps and joint config that in any way resembles this joint PJP or CJP groove.
Am I missing something in the code that resolves this? Specifically any denominational requirement for the length of faying surface on fillet welds? What course of action would you advise?
Thank you for any assistance,
- Caleb

Caleb,
I'm not sure of the plate thickness, it looks (from the photo) to be about 3/8”. If that's the case these 1/4" welds are undersized. That said:
This is a common Fillet weld on a Corner joint. If you have a copy of AWS D1.3 Fig 3.2a you'll see a picture of it.
Questions I would ask…
Does the shop/contractor have a WPS for welding this?  The fillet looks to have been done vertically down. This would require testing. What is the process used?  It looks to be GMAW-S. If so, this would require testing also.
I'm sure your cracking is due to insufficient throat. You can fix that by requiring multiple passes.
Here's where you should go with this…
Ask about the WPS and the process. If they are not in compliance, take out a rubber hose and beat them until they are (that’s a metaphor for fix that first 😊).
Ask the engineer to change the weld call out to:
Weld size = T (remember, T is thickness)
Require a Convex contour (that will insure the throat size)

That should do it.
PWC