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

AWS-D1.3 Weld Procedures

We weld Sheet Metal to AWS-D1.3. Our current WPS is outdated and needs to be updated.  Our customers are asking for a separate WPS/ PQR for Fillet and Groove Welds. Until now, I believe we had both Fillets and Grooves covered by One WPS/PQR.

I have more questions than answers, so I may need outside help in dealing with these mega companies.

 

Best regards,

Sheldon M, Sr. Mfrg. Engineer, CWI

Sheldon,

Communicating welding requirements can be challenging company to company regardless of size.  Sticking to the requirements of the code is one way to make that communication easier.  I learned from a mentor a while back that when answering code questions the CWI needs to open the book and, “put your finger on it.”

Your question as I understand it is; does a WPS/PQR for Groove Welding qualify Fillet Welding and does a single WPS qualify all Grooves?

There are 2 ways you can qualify a WPS per AWS D1.3.  You can use information in Clause 3 and develop prequalified procedures or you can perform actual qualification testing per Clause 4.  Either is perfectly acceptable. 

If you can use prequalified procedures you will need to write separate documents for each configuration (3.1A, 3.1B, 3.2A, 3.2B, 3.2C…) that you use in production.  And some of those configurations will require you to write more than one WPS.

If you had written weld procedures for all the prequalified joints in AWS D1.3 you would have a minimum of 16 different documents.  They may all contain the same welding parameters, but each will need to be written separately.

As for qualified WPS’s, Clause 4.1 keeps it simple, “A Welding Procedure Specification (WPS) shall be written for each type of weld as shown in Table 4.1…” and as for the PQR, “A Procedure Qualification Record (PQR) that records the actual values used to qualify a WPS shall be written.”

Here at McNeilus Truck we have a total of 133 WPS’s and 58 PQR’s in our records.  Each was required because some variable was off just enough to require another document.  We have a lot of Customers inquire about our welding documentation and we’ve not let them down yet.

Good Luck

Maintaining Welder Qualification

Jeff P. a Welding & Robotic Engineering Mgr. MN asks...

"A Welder is no longer welding but wants to maintain his qualifications “period of effectiveness”. We allow them to weld 4 hours in production to maintain that qualification. Of course they could always retest, yet 4 hours seems like a short time to stay “in the groove”. What say you?"

PWC:
As with any skill, ones ability to perform welding will very person to person. Most Welders can pick up a stinger after a 25-week layoff and start in right where they left off. Others need time to get back “in the groove”.

As a good friend, Jeff knows me as a “literalist” when it comes to code speak. His question made me do a little digging, of which I enjoy and from which I always learn. I reviewed several AWS, ASME and API documents and found one commonality. All required requalification testing when there is reason to question the Welders ability. Beyond that, they varied.
API-1104 makes no mention of a 6-month time frame. ASME Sec IX and AWS D1.1, D1.3, D1.5 and D14.3 all have similar statements; “The Welders qualification shall remain in effect indefinitely unless the Welder has not engaged in the process for a period exceeding 6 months.” None of the codes/standards I reviewed mentioned a “hands-on” minimum number of hours to maintain qualification, nor did their commentaries suggest one.
Imagine in a production environment such as Jeff's, a Welder with 2 years experience decides to mix it up a little and takes a job in the Paint Department. After 6-months can they still be considered a Welder? Possibly. How about after the next 6-months? Then the next? Four years after taking that Painter position this Welder has accumulated only 32 hours of welding experience, 4 hours at a time. Now I’m beginning to develop a reason to question his/her ability.
As welding decision makers we need to pass judgments’ based on code requirements and code intent. I’ve always fell back on, “Is there reason to question the Welders ability?” If there is not, then allow him/her to practice their craft. If there is, re-test them and evaluate their ability to make sound welds.

What are the reasons to oscillate a weld process

Vince H. from Oshkosh Truck asks,

"What are the reasons to oscillate a weld process?"

There are a number of ways and reasons a weld process would be oscillated. Oscillation is the side to side manipulation of a weld in progress. It is measured in amplitude (how far), frequency (how often) and dwell time (for how long).

Spend any time around GMAW (Mig) robots and you'll notice the torch is in a constant side-to-side motion. Typically referred to as a weave, this form of oscillation helps that robot find its way along the joint by monitoring changes in the arc. Another good example of oscillation would be a Pipefitter using the GTAW (Tig) process and a "Walkin' the Cup" technique. He or She will do this to minimize fatigue on their body, increase bead width and improve tie-in at the welds toe. A real craftsman will rock that Tig cup along the joint and make a beautiful finish weld, with a consistent face, completely around that pipe joint. It can be a real work of art (or a real cobbled mess for that matter).

Other types of oscillation may be manipulating the molten weld pool by using a magnetic force. Common with (but not limited to) mechanized GMAW and GTAW processes, this magnetic force will move the molten puddle (not the torch) from side to side. I've used this technique to increase bead width for customer appeal, but it can equally be used to improve sidewall fusion or tie-in at the weld toe. Some wire fed processes (SAW or ESW) will actually twist the electrode as it is fed as a form of oscillation.

Oscillation helped a Steel Worker using Electroslag to fabricate components for San Francisco's Bank of America building. It aided the arm fatigue of a Pipefitter as he built Louisiana's River Bend nuclear power plant. It will also assist the Iron Worker that will build the One World Trade Center, to achieve better weld toe fusion, allowing his or her welds to transfer stress smoothly between support beams.

Want to know more about “Walkin’ the Cup”? Follow this link:

(http://www.millerwelds.com/resources/articles/TIG-gtaw-cup-walking-pipe-welding/)