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BB, Wow this is Huge!!!!!. My company at present requires all welders to be re-qualified every 6 months regardless of certifications. We currently have over 200 welders on-site and expecting 30-40 more. You can imagine the costs, logistics and tracability nightmare for the QA department. I am new to this company and was told that the senior welding inspector/engineer has requested this. We are working to AWD, AWS, MIL, ISO standards but i’m not sure if any of these standards require this?
AS1554 clause 4.12.2 (a) only states welders ‘qualified’ to As1796 etc are deemed qualified (meaning pressure welders ‘qualified’ to pressure weld for company A can structural weld within company A without qualifying providing they dont change processes…no mention about ‘certified’ welders being exempt from ‘qualification’).
Also in the first edition of WeldED 2010 (under the news tab on this website) is an article about AS1554 structural QA and welder qualifications (page 19) – “Additional welders for the project must complete a weld test coupon within the essential variables of the weld precedure”.
page 20 – Welder re-validation- ” essentailly states that welders must be tested every 6 months via NDT to ensure compliance”. and the NDE applied to the work scope extends the revalidation….Does not mention coded welders to AS1796 are exempt.
BB, can you please post some reference material, clauses or information from Australian Standards or American standards (if your aware) for me to research and read which could save myself and others a lot of time and money. I will need proof in writing if I am to change the system at work if its not needed! This might bring me a promotion!!! ;D
I appreciate your time and effort BB.
Regards
IG
BB, thanks for your reply (its great to have experienced guys like you on here)..
I understand and agree what AS1796 – clause 2.5.5 says (meaning that “Certification” never expires unless) :
(a) The welder is incapable of undertaking his required duties.
(b) The certificate has been proven to be fraudulently obtained or illegally used or both.but…..
can you help explain why AS1554 talks about “Reapproval or Qualification SHALL be required if any of the following conditions apply:”
(ii) The welder changes employment. Under such circumstances, the new employer shallqualify the welder who has changed employment.This sounds like a contradiction to me! It does not exempt ‘Certified’ welders certified to AS796 etc…. and says ‘Shall’.
Regards
IG
With regards to the capping run in the 2G position, I have had great success with feeding the filler wire toward the top of the weld prep/joint only (giving it excessive over fill at the top) then letting the pull of the tungsten electrode and gravity pull the excess molten filler metal down to fill out the bottom (this has to be done quickly though). After a lot of practice you can get a near perfect even top and bottom weld bead.
With regards to walking the cup. Its true regarding site welding and being crammed in between piping and tight spaces…..you can forget trying to walk the cup! But if your goal is to work in a workshop, manufacturing new pipelines and components etc, then learning to walk the cup is well worth it as many TIG(GTAW) welders now adopt this style (in workshops and general pipe site work)so its nearly expected of GTAW welders these days. It also produces great looking welds if you master it. One other great advantage of walking the cup (besides an appealing looking weld) I found when doing my No.7 ticket was you eliminate the problem of the small test piece over heating and burning the crap out of your torch hand or fingers.
From my point of view, I guess it cannot hurt learning both (walking the cup and free hand) techniques if you want to be remain employable and can adapt from general workshop projects to tricky on-site welding jobs. Both techniques have their advantages.
Good Luck with your certificate.
Can others shed some light or research papers to the question, I would be interested to know why we don’t use it?
If not then I’m guessing then that it really dosen’t matter. The differences must not be substantial enough in the real world to worry about compared to on paper.
As far as i’m aware our standards and welds seem to be holding up pretty good here in Australia. I havent heard of many failures or catastrophes caused from arc energy v heat input differences. Is the extra effort and calculations really needed?
As far as I am aware, the numbering classification system for SS electrodes is more to do with everything else except tensile strength.
AS/NZS 4854-2006 has detailed information regarding the chemical compositions, positions, polarity’s and tensile strengths of the Stainless Steel electrodes. Page 10 of AS/NZS 4854, table 3 has the mechanical property requirements for the Stainless Steel electrode groups.
Minimum tensile strenght for:
18 8mn (not listed as 304) – minimum 500 Mpa
308 – minimum 550 Mpa
308L – minimum 510 Mpa
316 – minimum 550 Mpa
down to
316L – minimum 490 Mpa
Remember these are the minimum requirements and higher tensile strengths are usually obtained by the manufacturer’s.Or you can obtain the manufacturer’s tensile strength data reports. The CIGWELD pocket hand book is a good guide to have as well.
AS/NZS1553.1-E4110 and E4818 have been superseded by AS/NZS4855-2007 E4310 and E 4918.
41-410Mpa is now 43-430Mpa and 48 – 480Mpa is now 49-490 Mpa). I am not sure why AS1554.1 etc have not made any ammendments to the standards yet?What limitations does a pre-qualified weld procedure have on the thickness range? Is it limited to the actual thickness used?
AS3992, Clause 2.1 (c) …..”Table 5.4 which does not apply to pre-qualified procedures”;AS3992, Table 5.4 – Range of thickness qualified.
Cheers
IG
