"Put your finger on it"

Hi, Paul.
I was seeking advice from you regarding D1.1  I'm a welding instructor at a steel mill in Northwest Ind.
We were sent 12 yrs ago to Hobart welding school for train the trainer class and to certify in all positions,limited & unlimited thickness plates w/backing. All SMAW, 7018 rod. (Did not like Hobart's 7018 rod). We believed that we are Qualified to qualify welders to weld anything structural in our mill. Does this sound correct or our we missing something?
Also the big question is, does D1.1 say you have to certify to weld structural or just qualify through the testing procedure to weld structure? A new instructor is saying we have to certify I do not believe this is what D1.1 says.
Any advice would be helpfull, Thank you for time.
Thanks, Pat

Hi Pat,
Hobart is a great school and the Train the Trainer program was a great idea.
If your company accepted the Hobart documentation as your Welder Qualifications (common) and your company maintained a Welder Continuity Log (see: http://www.thefabricator.com/article/arcwelding/arc-welding-101-d1-1-welder-documentation) and as long as there is no reason to question your ability, your Welder Qualifications will continue to be current.
Although the AWS Certified Welding Educator (CWE) program would require you to maintain your Welder Qualifications, being a CWE is not a code requirement for those of us who train and qualify our Welders, so anyone your company deems competent to do so can train and qualify your Welders.
As far as qualifying Welders to weld anything structural in your mill… you would need to determine what governing documents covers the welding requirements of your mill (D1.1, D1.3, D14.1…) and insure your Welders are being qualified to those requirements.  Those Welders would need to be qualified to a (or many) test procedure(s) and the test procedures would need to encompass all of the essential variables listed in the code(s) being used.  (I know… it’s enough to make your head spin)
Bottom Line: When someone comes to me with a code requirement that I don’t believe to be accurate, my first response is to ask them to “Put your finger on it”.  Equally important, when someone asks about a code provision I would never give an answer until I had ALL the required information and I was able to “Put my finger on it” as well.

PWC

Those damn CVN requirement...

Paul,
Do you mind my asking a quick question drawing from your expertise of AWS D1.1?
Table 4.6 of AWS D1.1-2010 is a list of supplementary essential variable changes that would require WPS requalification due to CVN (Charpy V-Notch) testing requirements.  Under base metal (item 2) it indicates:

“minimum thickness qualified is T or 5/8” whichever is less except if T is less than 1/4” then the minimum thickness qualified is 1/8”

I take this to mean that to qualify a PJP groove weld of a 3/16” plate a weld procedure would have to be qualified using 3/16” thick material  (“minimum T or 5/8” whichever is less”).  Do you agree?

I had been going off of the table 4.2 where a 1” plate would qualify for a range from 1/8” to unlimited thickness.  But that table is not intended for Charpy requirements.  So I may have been wrong with using table 4.2 when Charpy requirements exist. I can see the need to qualify the thinner materials when CVN is required due to the heat input changes due to the thickness changes.  But just want a second opinion.

Thanks,
Wes

Oh those damn CVN requirement...
I currently have 2 clients that I'm working with on this issue. Your assessment of the CVN Supplement is correct.
What we advised for our client to do was to machine the test plates to a nominal of 0.230" (because I also wanted to insure I was under 6mm to eliminate any code questions). We completed PQR's on 0.230", 0.3125" and 1.0" material, that covered our range.

Other things that bite ya for CVN requirements is...
"Multi vs Single Pass": Most PQR's that are typically run are multi pass.  These multi-pass PQR's would not qualify single pass welding.
-and-
"Max. Interpass Temp": If interpass tempuratures were to be measured under 125F the Maximum qualified interpass tempuature qualified would be under 225f. This would limit Preheat Catigory A and C Steels to 1-1/2" max. and Catigory B Steels to 2-1/2" max.

Good to hear from ya Wes.
PWC

GMAW Globular Transfer

Paul,
I work at a machine shop where I am employed as a qualified welder to AWS-D.1.1. I was wondering why it is that you can certify 75% argon and 25% CO2 when you are not allowed to use a short circuit transfer on materials over 3/16". I read your article every month and in order to obtain a spray transfer you need at least 83% Argon but yet I passed on a 1 inch test piece.

Thanks K. B.

Your question insinuates that if your shielding gas mixture is not Argon rich enough to obtain a Spray Transfer mode the only alternative is Short Circuit Transfer, that's just not the case.
When using a 75% Argon and 25% Co2 mix you would not be able to achieve a Spray Transfer, but achieving a Globular Transfer would be no problem. It is quite common to complete the test you discribed (Unlimited Thickness to D1.1) in the GMAW Globular Transfer mode for all positions (3G/4G) successfully.  This is a fairly typical test commonly given in todays construction industry.  I think you will find Globular Transfer a prefered transfer mode in industries that utilize a 75/25 mix.
As for Short Circuit, when I mentioned in an earlier article, the possibility of incomplete fusion being a concern on materials greater than 3/16th inch, I prefaced that by including, "... in certain positions and progressions...".  Completing an open root limited thickness Welder Qualification in the Vertical progression (Root Down/Fill & Cover Up) is a very common transfer mode used during testing.  In fact, a test of that nature, Root Pass with Short Circuit, Fill and Cover Pass in Globular, would successfully qualify a Welder in 2 processes (GMAW-S & GMAW) in a single test.
That would be a good Welder Qualification to have in your wallet.
PWC

A Welding "Ground" doesn't ground anything!

What makes a good ground (Work Lead) connection and why is it important?

In a welding circuit, current needs to pass through as few connections as possible and the circuit it self needs to be as short as is practical.
On the positive (+) side current passes through the (+) stud connection, the feeder connection, the Gun connection and the contact tip (to the wire) connection. With the exception of the wire, all of those connections are typically, copper or brass.
On the negative (-) side current should passes through the (-) stud connection, the cable to the Work Lead (ground) clamp, possibly across a rotating surface and then to the work piece.
When any of these connections are anything less than clean copper or brass to clean copper or brass the possibility of a poor connection and a current and/or voltage loss exists. These losses can be great enough to run outside the parameters of the weld procedure causing spatter or a lack of fusion. That can get a welder into trouble.
Some good examples of poor connections would be:

• A Work Lead (ground) connected to a building column. 
• Using a steel building column and a steel bolt, this connection will oxidize (rust) and create resistance.
• A Work Lead (ground) connected to a steel plate run across the floor. 
• Of course the initial connection is the same as the building column. 
• When that steel plate isn't of a sufficient size (area) and that plate is joined by one or several welds (extra reduction in area) the condition are ripe for a drop in current and/or voltage.

The 2 conditions mentioned above also create a safety issue. Once a Work Lead (ground) contacts a building it gives current alternate routes. One of the most popular is through a jib or bridge crane.

Aside from creating havoc with the cranes electrical system, current passes through the lifting devices (cables, hooks and chains), heating them over and over and thus weakening them and making them susceptible to failure.
One last good example of a poor connection would be an unlubricated rotary clamp, or a rotary clamp lubricated with a lubricant that is not made for electrical connections.

A key to quality welding starts with a good quality circuit and a key component of that circuit is the condition of the Work Lead (ground).

Side Note: Notice I’ve replaced the word “ground” with “Work Lead”.  You should too.  Keep in mind, a welding “ground’ doesn’t ground anything.
PWC

"All Welding Shall Comply with AWS-D1.1"

Paul,
I am a welding instructor/inspector. I have a business client that builds control panels and a potential client of theirs is requesting that they conform to AWS D1.1 standards on a control panel. Seems odd to me what the customer is wanting? Does or can a company become AWS D1.1 certified? Is there a certain process they have to go through to become a D1.1 facility? I tested some of their welders over a year ago to the sheet metal code. Looks like they would want them to conform to D1.6-Structural welding Code - Stainless Steel? Thanks for any help. I got your name from practical welding.
John

Hi John,
Let’s dispel a few myths: Companies are not AWS-D1.1 “Certified” or “AWS-D1.1 facilities”. They simply comply, or they do not, and they call on folks like you and I to insure that. It’s not uncommon for contract documents to call for compliance to AWS D1.1 when the work being requested falls outside the limitations of AWS D1.1. The code is so accepted throughout industry that often those calling it out are unaware of its requirements. It has become some-what of a “Boiler Plate”.
The D1.1 committee recognizes this. If you look to the Limitations of D1.1 noted in Cause 1 at 1.2 it states, “The code may be suitable to govern structural fabrications outside the scope of the intended purpose.” It then goes on to state that the user may be better off looking into the requirements of other D1 documents that are more practical for your application (I used a little creative liberty in that last line).
In your case, AWS D1.3 and AWS D1.6 are far more applicable. Focusing your procedure and welder qualification on these codes will (a.) comply with AWS D1.1 and (b.) save your company, or the company you are working with, boat loads of money.
You could certainly review the job requirements and develop the requirements to AWS D1.1, but you would find yourself doing PQR’s and Welder Qualifications that may not have been required if you had used the Pre-Qualified procedures laid out in AWS-D1.3 and AWS-D1.6.
Using documents like AWS-D1.2, D1.3, D1.4, D1.5 and D1.6 when your welding doesn’t quite fit in a D1.1 box is certainly considered acceptable when your contract documents read, “All welding shall comply with AWS-D1.1”.
PWC

Exfoliation and Bed Sheets

Preparing for a trip to Oregon for my little brothers wedding my wife Dianne bought me an Esquire magazine. “You just need to read this.” It sits around the house, showing up everyplace I find to relax for a moment. Finally, I pick it up. In amongst the men’s fragrances, schwanky alcoholic beverages and Mini Cooper ads is a section titled, “Grooming – Man at His Best”, sub-title “Summer Feet”. After reading about pumice stones, exfoliation and lotions it hits me, “This is why they bought this.”

Being one far too advanced to fall for simple trickery, I asked, “Is this why you got me this magazine?” Her response, “Well, you’re not going to find this stuff in your damn welding magazines.”

She’s right, so let’s change that. Let’s talk PPE & hygiene…

Starting at the top – Your hard hat has a service life that few folks monitor. It is designed to protect you once. When it does, we say thank you and replace both the shell and head band.

Days can get long and hot. I put hard hats, welding helmets and jock straps in the same category… I don’t share them, you shouldn’t either. Would it kill you to wash or replace the head band in both from time to time? Maybe you have helmets or face shields that are stored at equipment and used by others. Keep a disinfectant (wipe or spray) available for everyone to use.

You spend your whole shift singing into that Welding Hood. Break it down and clean it out with a little soap and water. It also wouldn’t hurt to wear a disposable respirator. It won’t do much for your singing, it tends to muffle the sound (your co-workers will appreciate that) but it should keep your lungs and helmet clean. Keep in mind that Positive Air Flow hoods have their own replaceable components. Change them regularly. And I don’t care how many generations have passed down your Huntsman, when it’s cracked we don’t duct tape it, we replace it.

Ear protection, whether muffs or molded or disposable, need cleaning or replacing regularly. For muffs or molded hearing protection, always follow the manufacturers’ recommendations for maintenance. For disposable hearing protection, replace them with a new set every time you remove them.

Protect your hands with gloves that are appropriate for the Weld Process you are using. Gloves for GTAW (Tig) can be significantly different than the gloves used for FCAW. Insure heat and light can not penetrate them. Replace gloves with any holes. Replace leather gloves that shrink up so bad you can’t get your trigger finger in them. Don’t get them wet and don’t get them oily. You hands are counting on you to protect them. Choosing a glove because it’s light could be a bad decision. Choose a glove because it’s right.

Leathers, flame retardant jackets, chaps need to be free from holes and frays. Unless they can be repaired by a Leathersmith, they should be replaced. Insure they cover any cotton clothing from ultraviolet rays. A day of exposure to the welding arc can be hell on your neck, wrists or crotch (ouch). Insure your PPE protects you completely.

Finally your boots, insure they are appropriate for your welding environment. Snow and rain can be hard on leather. Waterproofing can do wonders for your feet over a 10hr day. Keep your socks dry. Keeping a fresh pair can be great around lunch time. Gravity will insure all spatter and sparks land directly on top of your boots, make sure your laces are ready for that.

And as noted in Esquire; a pumice stone to the foot and a little lotion may just keep your significant other happy and lengthen the life of your bed sheets.

PWC

GMAW-S & Pre-Qualified Weld Procedures

The company I work for welds with GMAW-S and all of the Weld Procedure Specifications (WPS) that we have are from pre-qualified AWS-D1.1 welds. When I look in D1.1 I find that GMAW-S is not a pre-qualified transfer mode. Are all of our WPS's therefore null? If I understand D1.1 correctly we would need to have a PQR for all of our WPS's because they are GMAW-S, is this correct?

 It seems like GMAW-S is the most common, or at least a very

common, GMAW transfer mode why in the world is it not pre-qualified?

Thank you for your insight, Martin

Martin, Love the question(s). The short answer is... Yes, but just to clarify…

When you mention GMAW-S the transfer mode referred to is Short Circuit Transfer (See AWS-D1.1 Annex K, “GMAW-S”). You are right to note that GMAW-S’s use is wide spread. You are also correct that GMAW-S is not a pre-qualified process, per AWS-D1.1.

So what’s up with that?

AWS-D1.1 is the Structural Welding Code for Steel. Its intent is to be used with materials 1/8 inch thick and greater. The concern by those who determine the requirements for pre-qualified procedures is, welding using the Short Circuit Transfer mode has the potential to generate a lack of fusion. It has been my experience, after running hundreds of PQR’s, that this lack of fusion becomes consistent on material thicknesses over 3/16 of an inch in certain positions and progressions.

That’s not to say GMAW-S can not be used with a pre-qualified procedure. AWS-D1.3 is the Structural Welding Code for Sheet Steel. Its intent is to be used with material 3/16 inch thick and less. Clause 3 of AWS-D1.3 lays out the requirements for developing pre-qualified weld procedures using Short Circuit Transfer.

AWS D1.1 in Clause 1.2, “Limitations”, encourages the use of D1.3 on materials 3/16 inch thick and less. So using pre-qualified procedures for Short Circuit Transfer is do-able, it simply has to be done to a different Structural Welding Code.

PWC