Monday, July 10, 2017

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

Tuesday, July 4, 2017

Check That Liner First

Jason G - Is it acceptable to use .045 wire with a 1/16th contact tip?

Jason,
That's not a "code" question, that's a "weld process" question.
My answer:  You should not have to and there is good reason not to.
The contact tip is the location where current from the electrode lead is going to transfer to the actual electrode (wire).  The larger diameter the hole the wire is passing through, the poorer the transfer.
Of course, a contact tip that is too small a diameter will lead to feed problems, but it would not be common for a contact tip manufacturer to manufacture 0.045 inch diameter contact tips with too small of hole.
You may find yourself experiencing feed or burn-back issues and thinking that increasing tip diameter should solve your problems.  Doing so may help minimize a symptom, but you have not corrected your core problem.
The first place I'd look for solving THIS problem is the gun liner installation.  Gun liners, when installed, need to rest tight against the defuser (part holding the contact tip).  Many mistakes can be made when installing a liner.  One of the biggies I see, is cutting it too short.  A short liner leaves a space between the end of the liner and the back of the defuser.  This space will allow the wire to wobble before entering the contact tip, leading to burn back.  It will also leave space for the buildup of metal shavings which can eventually become the "point of transfer" and lead to burn back.
Someone who does not understand the proper technique for installing a liner will change the liner once problems develop and then not realize they have just set themselves up for failure and frustration.
Always follow the gun manufacturer’s instructions and before cutting it to its final length keep these tips in mind:
1 - Keep the gun as straight as possible.
2 - Mount the gun securely onto the feeder.
3 - Calculate the length the liner needs to extend past the end of the gun (often the gun manufacturer will list this dimension).
4 - **MOST IMPORTANT** Before cutting the liner at that dimension, apply pressure pushing the liner into the gun (you'll find the liner will easily move 1/8" - 3/16"), hold that pressure, measure and cut.
5 - **EQUALLY IMPORTANT** File down the bur formed by cutting.
Give that a try.
PWC

Sunday, March 5, 2017

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 3rd 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