The Facts about Weld Porosity   As printed in The Welder Magazine

Do you give the Welder "test taking tips"? -or- Do you shut up and let the Welder pass or fail on their own?

So, a company is paying you to help them comply with AWS/D1.1 You've written the WPS's and now it's time to qualify the Welders. Do you give the Welder "test taking tips"? -or- Do you shut up and let the Welder pass or fail on their own? -and- Once they fail, do you give the Welder test taking tips before the re-test?

Keep in mind the premise... a 3rd party inspector helping a company that requested it, comply with AWS-D1.1

Often, in fact usually, when I'm in this situation, it's a small company looking to bid on a job that is requiring them to do something they've never had to do before; show proof of compliance to the structural welding code. These companies are too small to have a Welding Engineer on staff and wouldn't have a Certified Inspector. Generally, what I find, they have a Welder they've hired, or has been working for them for some time. His/Her qualification documents (if any) are from a previous employer. The company is counting on their Welder to know all that is needed to know about welding the product.

I'll also find that the company needing to comply with AWS-D1.1 doesn't own a copy of the code (or the copy they have is 2-3 revisions old).  So now they've called me to see if I can help them out. I'll typically tour the shop, view the product, watch how the sausage is made... then I'll come up with a list of recommendations;

• These are the codes you need to comply with (typically D1.1 and D1.3, but often others as well).
• These are the Pre-Qualified WPS's needed.
• These are the Qualified WPS's needed.
• These are the Welder Qualifications required.

Total cost can easily fall around $3k-$10k, so we break it into small chunks. 1st the Pre-Qualified WPS's, then some Welder Quals... and that brings us back to my original question, "Do you give the Welder test taking tips?"

I'm going to provide the Welders a detailed WPS. I'll provide detailed test instructions. I'll let them know the acceptance criteria (visually acceptable root pass, cover reinforcement/crown not greater than 1/8"...). I'll answer every question they'll ask. Beyond that, I have to leave them on their own. Under this scenario I have to know / they have to know, "Do the skills and techniques that they have/use today get them the required result?" Most of the time, they do not. Failing the Welder Qualification test shows the Welder and the company that the process they currently have in place doesn't work. Something needs to change.

Had I offered helpful tips on the initial Welder Qualification, and the test fail, the only response would be, "The Inspector told me to ____ and that's why I failed." On the retest I will always ask, "Can I give you some tips?", but never on their initial test.

In a School or Training situation, that is a different scenario, but this isn't training. This is determining if the process you currently have in place yields the result you need and if not, what needs to change.

Thanks for reading and following.
PWC

The Same Welder Quals Over and over and...

Paul,
Why do companies require so many different test from one place to the next if your always doing the same kind of work?
Jacob M.

Jacob,
Certain tests are required to qualify you for the correct material, process, thickness and position.  The code you're welding to will specify the test requirements.  Often, these tests can look far different than the actual welding you'll do in production or on the job site.
Each employer is responsible for their Welders qualifications, so if you hop from employer to employer each of those employers are required to give you the required tests.  The employer is held liable for your qualifications, so they would not typically accept a qualification from another employer.

PWC

Find Your Resident Experts

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 3^rd 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 experts on 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

Don't forget to Ping that Weld

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

Become the "Qualification Guru of Choice"

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

AWS-CWI's, Who needs 'em?

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

No means No

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

What's With Weave Width? (Woah!)

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

“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

"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

Weld Penetration Problems

Ken P...

Our problem, we get linear porosity at the furthest point of penetration (heavy plate). The size of porosity is 0.3mm dia. but occurs regularly in every weld sectioned so far. Please suggest any steps, which should be checked.
Weld Info: Semi-Automatic process, Spray Transfer, Blasted Material, Electrode: 0.045" ER70S-6, Gas: 91Ar / 5Co2 / 4O2 @ 35cfh, WFS: 485ipm, Travel Speed: 13ipm, Amps: 335A, Voltage: 29.3, Finished weld size is 12mm

Ken,
I would suspect that your weld penetration profile is showing “finger penetration” (Not sure if that is a real term but), a real deep area of penetration at the weld root. The profile is much deeper (at this location) than it is wide. This will cause this area to open up during solidification.
Grab your copy of AWS D1.1 and check out the Commentary section at C3.7.2 “Width/Depth Pass Limitations” also, Figure C-3.2 “Examples of Centerline Cracking”.
I was asked to troubleshoot a similar condition during a job interview for a former employer. To save money, they had changed a process from an 0.045 dia. electrode to an 0.052 dia. When they made the change they did not change any other parameters. The high wire feed with the larger diameter electrode created a considerable increase in current which equates to a considerable increase in root penetration. Like you, everywhere they sectioned, they had this pore, which I believe was more of a linear void. A reduction in WFS, although not popular, eliminated the problem. P.S. I got the job!
Typically, a reduction in current (WFS) will reduce this finger penetration and this should remedy your issue. One other thing; yours is a weird shielding gas mixture. Not sure why you would go with so much Oxygen but I don’t know your whole story. If you can, replace the Oxygen with more Co2. Perhaps that will change your weld profile as well.

Good Luck! PWC

"It's Good to be Me!"

Which welds are required to be visually inspected and by who?

Ed called: “We work on Off-Road and Lifting Equipment and our welders are qualified per AWS D1.1. Which welds are required to be visually inspected and by who?”

Ed, A few documents you should consider adding to your welding library are:
• AWS D14.1- Specification for Welding Industrial & Mill Cranes & Other Material Handling Equipment,
• AWS D14.3- Specification for Welding Earthmoving, Construction & Agricultural Equipment -and-
• AWS D14.4- Specification for Welded Joints in Machinery & Equipment
These welding specifications are a little more applicable to the industry <> services.

You asked which welds are required to be visually inspected and I had to snicker… There was a time in my life when on one side of my Hard Hat was printed “AWS D1.1 Sec 6.9” I would get this question, smile, point to my Hard Hat and say, “Look it up!”

AWS D1.1 keeps it simple, Clause 6.9 – Visual Inspection, “All welds shall be visually inspected…” Section 10.6 of D14.1 is similar, “All welds shall be visually examined.” That doesn’t leave a lot of “wiggle room”. A qualified inspector needs to visually inspect all welds.

As to who the qualified inspector is, I told you over the phone that a Certified Welding Inspector (CWI) isn’t required. Welding codes and standards typically accept the qualifications of a CWI but they don’t require certification. AWS D1.1 and D14.1 require inspectors to be qualified and that the bases for qualification are documented. In addition, D1.1 requires a regular eye exam.

As long as <> writes a qualification procedure for your inspectors, the inspectors conform to Para: (1), (2) or (3) [see D1.1 Para: 6.1.4.1 or D14.1 Para: 10.1.3] and <> maintains documentation that those inspectors meet the qualification requirements, visual weld inspection can be handled internally.

A great document to use as a guide for developing your Weld Inspector Qualification Procedure is AWS B5.1 – Specification for the Qualification of Welding Inspectors (http://files.aws.org/certification/docs/b5.1-2003-errata.pdf). This is a free download made available by the American Welding Society at www.aws.org

As for what I had printed on the other side of my Hard Hat… “AWS D1.1 Sec 3.1, 2nd Sentence”. Look it up! But that’s a whole other column.

"It's Good to be Me."

PWC

Pulsed Welding Equipment

Cory G. from Norther Iowa asks:

"We use the Pulsed GMAW process with Lincoln equipment. When setting weld voltage the Trim can be adjusted between 0.5 and 1.5
What do those numbers mean and how to they relate to weld voltage?"

Pulsed welding equipment can challenge the conventional wisdom we’ve picked up over the years using a good ol’ constant voltage (CV) GMAW (Mig) welder. With typical CV equipment, the Welder will select a voltage and wire feed speed (WFS) combination, possibly a percentage of slope and/or inductance and then be ready to weld. Today’s pulsed Mig equipment changes most of that.

Most pulsed Mig welders run on pre-set programs. The Welder will select the type of wire, the wires diameter, possibly a base material and the shielding gas used. From this information the equipment will look at the WFS selected and do a calculation as to what the optimum weld voltage should be.

Of course, this optimum voltage may need some type of adjustment depending on the needs of the Welder. Example: The optimum weld voltage to weld a flat position, 3/8 inch fillet (1F) at 475 ipm may not be optimum to weld a root pass in a horizontal groove (2G) at the same WFS. Understanding that, each manufacturer of this equipment has built-in, an adjustment for voltage. Think of it as a percentage of optimum voltage.

Manufacturers may give you a 0.50 to 1.50 range, or a 0 to 50 range, or something similar. All will call this “Trim”. Using the 0.50 to 1.50 range as an example, 1.00 would be considered the optimum setting. When you reduce your Trim from 1.00 to 0.85, you have reduced arc length and, in doing so, reduced weld voltage. Similarly, when you increased Trim to, say 1.15, you’ve increased arc length and, in doing so, increased weld voltage.

This is very similar to what you were doing all along on that old CV Mig equipment. When you reduced voltage, you were reducing arc length. Even with this new fancy equipment the age-old understanding that “Weld voltage has a direct relationship to arc length” doesn’t change.
What’s different is that a Trim of 1.00 for a given electrode (type/dia.) will give you a completely different weld voltage when you change electrode, shielding gas or WFS.

Most of today’s pulsed equipment will display average weld voltage as the equipment is welding, and some will continue to display it for a short period (seconds) after welding has stopped. This feature helps the welder monitor compliance to the weld procedure (WPS).

PWC

"It's Good to be Me."

B31.3 Processes

Question: Paul, I enjoyed reading your article printed in Practical Welding this
month, thank you!
I have a question relative to ASME B31.3 the code for chemical plant piping.
The area of this code referring to the type of welding process that is
acceptable is un-clear to me. I am referring to section 328.2.2,
..."welding procedures qualified by others may be used, provided that the
following conditions are met:( f ) The welding process is SMAW or GTAW or a
combination thereof"

Does this mean that the only acceptable process for welding has to be either
SMAW or GTAW, or is GMAW acceptable as long as it follows a written and
acceptable WPS?
And if GMAW is acceptable, must it be performed by a certified welder who
has been qualified in that WPS?

With your article being written about WPS's and referencing the same code I
have questions about, I thought it wise to seek your council.

I truly appreciate any enlightenment you can provide.
Thank you and regards,
Randi Kremer
Engineer

Answer: The section you are referring to (328.2.2) is specific to the use of weld procedures qualified by others (not qualified by you). When a fabricator wishes to utilize these procedures, they face many limitations. One of those, as you’ve discovered, is the process used.
There are many other allowable processes available but all would require you to produce a qualified Weld Procedure Specification (WPS).
ASME B31.3 section 328.2.1 mentions, “Qualification of the welding procedures to be used… shall conform to the requirements of… Section IX…” So ASME Section IX will layout your requirements for qualification.
The process that you are wishing to use, Gas Metal Arc Welding (GMAW), is included in Section IX as an allowable process. So, yes, you can use the GMAW process but you will need to qualify a WPS to do so.
As for your Welder being qualified to the new WPS, that is a bit of a “Chicken or the Egg” scenario.
A Welder typically wouldn’t be qualifie

d to a WPS before the WPS has been tested and developed and a WPS won’t be qualified until a competent welder completes it.
Code writers recognize this. ASME notes that a procedure qualification has a distinctly different purpose than a welder qualification.
ASME Section IX QW-100.1 makes the statement, “…the welding procedure qualification test establishes the properties of the weldment, not the skill of the welder…” Prior to that statement you’ll read, “It is presupposed that the welder… performing the welding procedure qualification test is a skilled workman.”
As for Welder Qualification, QW-100.2 notes that, “the basic criterion established for welder qualification is to determine the welder’s ability to deposit sound weld metal”.

So how does this apply to Campbell Fittings and their desire to utilize the GMAW process?
It sounds like you need to qualify the GMAW process. This can be done by any of your competent Welders. Once your Welder has successfully completed the Process Qualification testing he/she will be considered qualified. The limiting factor will be that the process will be qualified within a given range of essential variables and the performance (welder qualification) will be qualified within a different given range of essential variables.
Once the WPS is completed the welder who qualified it may need additional testing to utilize it in your specific application.

Example: Your Welder completed the Procedure Qualification test (PQR) in the Vertical (3G) position, on a Single V-Groove, with a backing strip and the progression was up. You would like to apply this same Procedure Qualification Report (PQR) to a similar joint but you intend to change the groove by eliminating the backing and weld vertical down. A new WPS could be written to reflect these changes and would not require testing, but your Welder would not be qualified to this new WPS.

Confusing? I know. When talking “Code Talk” always make sure you separate Procedure Qualification from Performance Qualification. I often see where these two consistently trip people up when talking weld qualifications. Consider contacting a competent Certified Welding Inspector who understands the ASME Codes to review your specific needs and advise you on additional testing requirements.

PWC

It's Good to be Me!

Vertical-up or -down in robotic welding?

Vertical-up or -down in robotic welding?

We have a weldment that incorporates 0.375-in.-diameter steel rods and a 0.060-in.-thick sheet metal stamping of 1018 CR material. Each weld is the same, 0.75 in. long with a 0.25- in. fillet, perhaps including weaving. The assembly is fixtured and welded robotically using GMAW with CO2 gas and repeated 100 to 300 times.

We utilize vertical welding, but which is a better progression, down or up?

Richard P.

Vertical-up and vertical-down welding are significantly different from one another in the technique used and the resulting finish weld. This is the reason welding codes consider this change in progression an essential variable and require additional testing when changing from one to the other.

From your description, I would have to conclude that of all the possible positions (flat, horizontal, vertical, and overhead), this is an ideal candidate for welding vertical-down. Your greatest concern in this application is going to be burn-through on the 0.060-in. sheet metal. Welding vertical-up will be difficult, if not impossible, in this configuration because of the low travel speed and high heat input. Welding vertical-up with GMAW typically requires a weave technique to carry the puddle and give you the proper bead profile. GMAW vertical-up is a deep-penetrating technique, and this characteristic is going to lead to consistent burn-through.

GMAW vertical-down, on the other hand, tends to lack penetration and side-wall fusion. These characteristics are undesirable in most applications, but given that you are using a fully automated system, tight control of wire feed speed (WFS), voltage, travel speed, and bead placement should allow you to counteract these characteristics and control your finish weld quality.

I’ve had a lot of success setting up similar applications in what I call the 45-degree vertical-down position. The key is using a slight drag angle (10-15 degrees) and keeping the arc on the leading edge of the puddle at all times. This is a little easier to do at a 45-degree incline than at straight 90 degrees.

If possible, consider a mix shielding gas (minimum 85 percent argon/maximum15 percent CO2) as opposed to the straight CO2 you are using today. This should reduce chances of burn-through and reduce weld spatter considerably. A 0.035-diameter solid electrode should work well in this application.
You stated the weld size was 0.25 in. Talk to the engineering team and your customer about reducing the weld size to 0.19 or even 0.125, which will help increase travel speed, ensure penetration into the root, and reduce cost. Large welds with no root penetration or side-wall fusion are of little benefit to your customers.

Do I need a welding procedure specification?

Question
Do I need a welding procedure specification (WPS) for my company when it is just me and all I do is on-site portable welding of a wide range of items?

Steven B-

Answer

Whether your company requires a WPS depends on the customers you serve. For example, if your company is hired to fabricate your neighborhood association’s new flagpole, using your skills and best judgment would most likely be acceptable. On the other hand, if you are contracted to fabricate steel supports for a new government facility in your hometown, a little more paperwork probably is involved.

Review all the documentation from your clients in detail. Ask questions if you are unsure. A common statement found in contract documents is "All welding shall meet the requirements of the latest revision of AWS D1.1, D1.2, D1.5, ASME B31.1, B31.3, API 1104 ..." This statement indicates written weld procedures and documentation are required that show your welders and welding process meet the code requirements. You need to know, before you strike an arc ... before you bid the job, if there are specific code requirements.

Does your company need (as opposed to require) written WPSs? Yes!
Without a clearly documented and followed process, it is difficult to communicate details of your welding to your customers. With a clearly defined WPS, everyone involved knows what is to take place. Should something go wrong, say that new flagpole drops on top of the neighborhood association president’s new MINI Cooper, you'll be able to show the insurance investigators that you are a professional and the failure was clearly not caused by an uncontrolled weld process.

In your company name you use the term Certified. To be a certified welder requires testing, typically to a nationally recognized standard. This is monitored by a third party, often a professional organization such as the American Welding Society (AWS) or a governing agency like the state department of transportation, and administered at an accredited test facility. These organizations would most likely require your work be completed per a qualified WPS to maintain your welder qualifications.

PWC
It's Good to be Me!

Look Inside >>  May/June 2009

Good Call!

We have is a stiffener bar (continuity connection) in a column that calls for (AWS D1.1) BTC-P4 for the flanges and fillet welds both sides in the web. The stiffeners were field welded. After assembling 35 connections we discovered no fillet weld on the bottom side in the web. Problem is we can't weld the bottom side of the stiffener now because of clearance. What are our options? Could we add more than the required 1/4” fillet on top of stiffener to satisfy the inspector? He is not offering any solutions. He just wants the requirements to be met, fillet weld both sides. If you can help, it will be greatly appreciated.
Thank you,
Brian N.

Brian,
Thank goodness for “on-the-ball” inspectors. The inspectors’ part in this construction project is to monitor the fabrication and erection. Should issues arise, he is to bring them to the attention of those who need to know. Speaking from past experience that can be a thankless job.
The inspector on your site is insisting the welding completed meets the requirements of the jobs documentation. When things go wrong and an inspector raises the “red flag”, it is often the case that those on the ground will look to him and ask, “What should we do?”
The inspectors’ first response should be “Contact the Engineer and come up with a documented solution”.
Often, when we start to brain-storm solutions on the job site, we don’t have all the facts or we may not understand all the requirements, to make the call. Example: Your suggestion for missing weld on one side of the joint was to increase weld size on the opposite side. There may be times when this is an acceptable solution, but if the engineers concern is the stress riser created from the missing fillet (which is often the case in today’s building construction) that oversized fillet would be of little benefit. And better to bring the issue into the light for engineering analysis now, than to find out after the concrete has set, that the fix was unacceptable.
Inspectors may or may not have the engineering back ground to make this call, but it is the engineer responsible for the project that should come up with an acceptable solution.
Brian contacted me by email to let me know that the solution to his welding issue was to backup, disassemble each connection, and add the original required ¼” fillet weld. Good call!