Welder Qualification using Partial Joint Penetration (PJP) Grooves

How would you evaluate a flare V-groove joint for welder qualification to AWS D1.1? D1.1 is not clear on how to test the prequalified joint (B-P11-GF) for welder qualification.
Thank you,
Dale

Hi Dale,

Thanks for writing.

If you take a look at AWS D1.1 Clauses 4.25 and 4.28 you’ll see that D1.1, for Personnel Qualification states that a Complete Joint Penetration (CJP) qualifies a Partial Joint Penetration (PJP) groove.

A Flare V- (and Flare Bevel) is a PJP.  Typically you would use the V- and Bevel Groove, CJP configurations laid out in Clause 4 for Groove Welding Personnel Qualification.

That’s not to say I would never use a Flare V- Groove for Personnel Qualification.  If Flare V- Grooves were a concern of mine, I would design a Workmanship Sample requiring the welder to complete the Flare V- Groove to my Weld Procedure Specification (WPS).  Then I would cut and etch it (usually at 3 locations) to evaluate size [(E)=3/4r, see B-P11-GF].

So I guess, long story short, you would always use a CJP Bevel or V- Groove for Personnel Qualification of Grooves (CJP or PJP) and you would only use a PJP as supplemental to verify size.

PWC 

Paul,

Thank you for answering my question, your input clears up some of my confusion.
I have a customer that is doing welder performance qualification to prequalified material and prequalified weld joint B-U4a-GF.  Looks as though weld joint B-U4a-GF will also qualify PJP flare bevel tubular according to Clause 4.25 and 4.28.
Regards,
Dale L.

Dale,

You are right on the money.
Don't hesitate to write again.
PWC

Weld Stops & Starts

My question is… Where can I go to find out about tie-ins being done all in line with each other and not staggered / spaced out as they should be. I am having trouble with my Mig welders making their welds all the same length and not staggering / spacing there stops and starts out. 

I need physical evidence in black in white to show them in a meeting I am having on Tuesday. 

Thanks, 

Allen T.

Allen,

It is understood throughout the industry that most weld defects are attributed to weld stops and starts.  We automate (or change from manual to semi-automatic) for the purpose of improving cycle time and quality.  Most of that quality improvement comes from the elimination of starts and stops.  Starts in welding can lead to overlap, incomplete fusion and slag inclusions.  Stops typically lead to cracks and undercut.  

Some of these discontinuities may be considered acceptable but stacking them on top of one another in a multi-pass weld is just “flurtin’ with disaster”.  

Stops and starts are a necessary evil in welding.  We can minimize their negative effects through techniques during manual welding, and through weld data settings for semi automatic and automated welding.

In GMA (Mig) welding those weld setting that can be added to many wire feeders include:

•  Adding a burn-back to keep the wire stick-out as short as possible to help with your next arc start.
•  Adding a post-flow (3.0 sec) to insure the tip of the wire is kept protected and clean.
•  Adding a pre-flow (0.2 sec).  This insures shielding gas covers the area before an arc is struck.
• Adding a slow run-in speed (-100 to -200).  This will reduce the “Snap” that often occurs when initially striking an arc.
•  Increased start voltage (1-2 volts).  This will also reduce the “Snap”.

As for your Welders techniques:

•  When striking an arc, start out ahead of the desired start point (1-1/2 x the weld size). When the arc is struck, backup quickly to the desired start point then begin your weld.  This will almost eliminate any overlap (cold lap) that is common with weld starts.
• When extinguishing the arc, weld to the desired stop point then back up (1-1/2 x the weld size).  This will fill the weld crater, slow the cooling rate, fill the undercut and reduce the chances of a crater crack.

You could probably search the internet for an article on weld stops and starts and get plenty of horror stories.  In that same search you will find oodles of “pixie dust” salesmen with a simple wire/shield-gas/power source that can take all those troubles away.  

Stick with common sense.  Set up your feeders with the settings that help improve weld starts and stops, and teach good welding techniques.

PWC

Welder Continuity Logs

Paul

I have a question on welder qualifications. Where I work we have had
guys certified for D1.1 for 15 years. But in the D1.1 book it says that
they need to weld in every 6 month period to keep it current. What type
of documentation do we need to keep on file to show that they have been
welding? I can not find this in the book so I want to make sure that we
are covered at this point.

Thanks Pat G. - CAWI

Good question Pat,

What you are talking about is called a Continuity Report or Continuity Log.

AWS D1.1 Clause 4.2.3.1 - Tells us that a Welders qualification is effective indefinitely as long as that Welder does not go more than 6 months without using that process.  ASME Section IX and most Welding Codes make similar statements. 

We are required to provide documentation showing that the welder worked with all the processes (GMAW, GTAW, FCAW, SAW…) he/she held qualifications in, from the time qualification testing was complete to today with no gaps in service greater than 6 months. I did a word search of "continuity" in D1.1 and got about a million hits for “discontinuity”, but zero for “continuity”, so it looks as though you are on your own as to how you maintain that documentation.

I've worked for several organizations and each has had different ways of doing this.

• I've maintained a simple Access Database where every 5 months I would go out on the shop floor and verify that each Welder is welding with the process they are qualified in.  I would then log the employee ID, the process and the date. 


• I've worked with local unions (http://www.pf597.org/) who would maintain these records for their members and provide me, the contractor, copies with a clear trail and no lapses greater than 6 months. 


• Today I have a software program that will generate a list of Welders by Plant Location, Department & Supervisor.  I forward those lists to the Supervisor every 5 months and they return them with the updates.  I update my database and I also sign and keep their hard copy.

 

There are many ways that the 6 month requirement can be broken:

• A welder enters active military service and then returns to his/her civilian job 9 months later. 


• An employee gets laid off and called back. (Fabricators typically monitor the 6 month time frame to save the cost of re-qualifying.)


• A Welder takes a Supervisor job, but a year later decides to go back to welding. 


• A GMAW (Mig) qualified Welder takes a job running a Submerged Arc Welder (SAW) for 7 months, then returns to Mig welding. 


• A Welder in a job shop may seldom uses one or more of the processes he/she has qualified for due to the shops work load.

All of these are common scenarios that have snuck up on me at different times in my career.  It's a pain in the neck, but a Welder Qualification is of no value without an unbroken Continuity Report.  That is the thing that will sting you in an audit. 

Showing a clear line from the date of qualification testing to today with no break greater than 6 months is required per most welding codes.

Is Weld Inspector Certification Beneficial?

Mr. Cameron,

Thank you for writing the monthly column Arc Welding 101 in the Practical Welding magazine. Your articles are very informative. I have a question concerning CWI Certification. I am trying to decide whether obtaining a CWI Certification through AWS would be beneficial to my career. I am presently unemployed and would like to increase my marketability to potential employers. I have a BS degree in Metallurgical Engineering plus over 20 years experience as a materials engineer primarily in the power generation industry. I would appreciate any insight that you could provide me. The course is being offered locally during the first week of August so your prompt response would be greatly appreciated.

Regards,
David P., P.E.

David,

Thanks for reading, I appreciate your writing and I’m sorry you find yourself in this position.

In the interest of “Full Disclosure” one of my many hats includes Adjunct Instructor for the AWS-Certified Welding Inspector (CWI) Seminars.  That said…

One common career path for Welders is to Inspector.  Dan Davis from thefabricator.com wrote an excellent article last year on just that subject (http://www.thefabricator.com/article/weldinginspection/so-you-want-to-be-a-certified-welding-inspectorr).  By now we’ve all seen the Bureau of Labor Statistics (BLS) numbers and read the many articles on the shortage of Welders in our industry.  I believe those numbers transfer over to other welding related careers as well.  With this shortage comes a lack of knowledge of subject matter throughout our field.

The welding world is made up of Inspectors, Welders, Engineers, Salesmen, Programmers, Purchasers, Managers and Metallurgists like yourself.  All of whom make decisions impacting welding every day. So where does the CWI designation fit in to this conversation?

Achieving the designation of CWI does not, in and of itself, make you a better Metallurgist or me a better Inspector.  What it does do is lets those we come in contact with know that we have a fairly good understanding of welding processes, weld quality and welding code requirements.  Those are important attributes for any weld decision maker.  That’s not to say all CWI’s have the same level of knowledge, but you certainly know a CWI’s base.

Although CWI positions are out there, it is not common that employers are looking for only a CWI.  The designation is often coupled with some other requirement such as; a Bolting Inspector, a Certified Welding Inspector w/UT Level II, a Welding Engineer w/CWI or a Materials Engineer w/BS & CWI.  Five years ago, these job designations may have come with a qualifier like, “Must be able to attain CWI designation within one year.” But that statement is becoming less and less common. 

So where do you find the training necessary to determine if you are ready for certification? I may be a little biased, but the American Welding Society (www.aws.org) holds regular seminars all across this country.  The AWS is one option, but it is not the only option.  The Hobart Institute (www.welding.org) offers an extended (80hr) class, The Lincoln Electric Company (www.lincolnelectric.com) offers a “pre” class (40hrs) prior to the AWS seminar and there are several schools, AWS Chapters and businesses that offer CWI training.

More and more employers are requiring certification as a condition of employment, because they can.  Adding the designation of CWI to your resume certainly would be considered a feather in your cap.

Freestylin'

Dear PWC,

I know of welding manufacturing companies that do not use WPSs, their welders are not qualified and their welders inspect their own welds! How can these companies get away with this type of practice?

Nelson M., CWI H.I.W.T.

Ah Freestylin’!  I find it’s best left to Rappers, Swimmers and Motocross and it doesn’t belong in the welding industry.  I too have been in many Freestylin’ fab shops, they lack documentation on their Welding Process and their Welding & Inspection Personnel.  That said, manufacturers are not required to weld to a code.  The requirement for code compliance is something a customer/governing agency places on them.

Typically, if I’m walking in the door, it is not to give awards for excellence in welding.  It is usually to determine, Are they in compliance? and if not, How do we get them there? and What steps do they need to take to maintain compliance? 

Consider this scenario:

Company A has built decorative fabricated metal products for years. There was never a code requirement. Their products had nothing to do with public safety, their Welders were skilled and business was good.  Enter the economic down turn

Company B, just down the street, builds off-road construction equipment. They too have skilled welders.  In fact, Company A and B share the same Welder training program. Company B’s people and process’s are backed and guided by all the right documents.

Stimulus Funds are granted for a highway project and Company B receives a contract. Because of a tight time schedule Company B requests help from Company A. Now what?

A down economy gets a lot of Fab Shops exploring other options and thinking outside-the-box.  If they are Freestylin’, doing so can quickly have them in hot water. 

Company A now has their work cut out for them, but this is not impossible. Where should they start?

1.) Purchase and review a copy of the code.  I’m surprised how many shops I go into that do not own a copy of the code they claim to comply with.  Often, if they do, it is several revisions old.
2.) Qualify the Inspector(s).  Someone’s got to be prepared to make the call as to whether welding is acceptable or not.  Codes require that the qualification of the inspector be documented.  This can be a Technician or Welder with the required background and knowledge, or a Certified Welding Inspector.

3.) Develop the required weld procedures (WPS).  A skilled Welder working with a qualified Inspector should be able to quickly produce the Procedure Qualifications (PQR) needed for the products to be welded.

4.) Qualify the Welders.  Keep it simple.  I’ve been in shops that require their welders to be qualified in all positions for all thicknesses, but they never weld in the overhead position and never weld groove depths greater than 3/8 inch.  You can loose a lot of good welders to an all position, all thicknesses test.

5.) Maintain the Welders and Inspectors qualifications. This is done by documenting their involvement in any 6 month period and monitoring their quality.

Freestylin’ I suspect companies just evolve that way.  Maybe they started out small and grew faster than they could keep up.  Perhaps they were in compliance at one time but the employee that managed compliance moved on and no one picked up the ball.  However they got there, it’s a risky way to run a business.

Weave or Stringer?

Hi Paul,
I'm a big fan of "Practical Welding Today" and have recognized your input for quite some time. I have a very generalized and basic question for you about a weld situation we have, and I feel that you are more than qualified to give an opinion.

We build steel tanks mainly for containing hydraulic oil. The material is A36 picked and oiled and the gauge will range from 10 GA up to around 3/8".  We are using Lincoln 355M power sources, GMAW process, ER70-.035 wire and 90/10 gas. Almost all of the tanks are made with an overlap design vs. a corner to corner weld. This creates almost all fillet welds, mostly in the horizontal position, and a few in vertical. The question I have is, given this design and end product, do you feel it's appropriate to do a weave or a stringer bead when welding these? This is a big argument here right now. We used to allow weaving and we had great looking welds on our product with minimum leaks. Recently we have put a stop to all weaving and are demanding that all welders use straight stringer beads. Now we have welds that look very inconsistent and overall "poor".  We also have a great number of leaks which take a long time to repair and re-test. I know that weaving is NOT allowed in certain weldments, mainly when high strength steel like T1 is used, (Greater HAZ, slag inclusions, etc.). Do you think that on a simple product such as this when high strength is not an issue the weave method is acceptable? I don't believe the WPS for this weld states anything about weave vs. straight.

Please give me your opinion.
Thanks! Steve R.
Manufacturing Engineering Dept.



Hey Steve, Sorry for the delayed response. That 355m, do you use it in the Pulse or CV mode?  Also, your shielding gas and wire combination is going to tend to give you minimal sidewall fusion dependent on the mode of transfer used.  An increase in Co2 will tend to improve sidewall fusion.  It will also lead to increased penetration which could lead to burn through on thinner material.  That being said... Your joint design (Lap/Fillet) should lend itself, just fine, to Horizontal (2F) fillets using a stringer bead.  When weld size is increased (t>5/16) a multi-pass stringer technique should be utilized.  This is an application where I would never suggest a weave when manually welding. In the Vertical (3F) position the progression should be Up (vertical down with a process that minimizes sidewall fusion to begin with, is flertin' with disaster). This position lends itself to a weave technique. Keep in mind, I'm not talking about a "Whip" motion that constantly moves forward, then back.  We are talking about a side to side movement. As for the look of the weld... Don't let your personal opinion of what looks good cloud good judgement.  The welds should be acceptable, as determined by the code you use.  Liking the look of a weave better, as opposed to stringers, is a personal opinion.  I would suspect that if tomorrow I walked on to the shop floor where everybody used a weave and proclaimed, "Beginning this day and all future days the weave technique will no longer be an acceptable practice!", it would take some time before Welders got use to the new technique (could be months) and I would expect the welding to look inconsistent.
PWC

With DC Welders, CV or CC, What’s the difference?

Teaching seminars across the country, that is a question I’m often called on to explain.  The best way I’m able to describe the difference between CV & CC is this:

Electric arc welding has 2 main variables, Current and Voltage.  Welding machines will supply both, but are only capable of consistently maintaining one of those variables.  The other is maintained by some other means.  Direct Current (DC) power supplies can be Constant Voltage (CV) or Constant Current (CC). 

A Constant Voltage machine will provide a consistent, preset voltage.  CV equipment is typically semi-automatic and wire fed.  Presetting the weld voltage, a CV power supply will maintain a constant arc length (because arc length is directly related to weld voltage).  

So what determines the current draw? On CV equipment the wire feed rate, wire diameter and electrode stick-out are what draw current from the machine.  Set at 28 Volts, your GMAW/FCAW equipment will set an arc length that that will remain constant.  As you increase wire feed speed or increase wire diameter you will increase your welding current.  By increasing current you will, in-turn, increase penetration.  On the other hand, maintaining that wire feed speed and increasing electrical stick-out will introduce resistance into the electrode and reduce current, thereby reducing penetration. 

When a Welder fears burning through, he/she will increase stick-out, which will reduce current and penetration, reducing the chance of burning through.  A Welder can easily reduce weld current 25-50 amps by simply increasing that stick-out.

A Constant Current machine will provide a consistent, preset current.  CC equipment is typically considered manual.  Presetting the current, a CC power supply will maintain that amperage setting. 

So what determines the voltage?  Remember what I said above about voltage being directly related to arc length?  Voltage will be maintained manually by the SMAW or GTAW Welder.  He/She will regulate voltage by moving that stick or tungsten electrode closer to, or further from, the work (and typically, less is best).

That’s why I can’t Stick or Tig weld with a CV machine, and I can’t Mig weld with a CC machine.  

IGTBM