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Hygienic orbital autogenous welding of 316L SS (0.065 inch wall thickness) with purge gas 90% nitrogen 10% hydrogen

  • 1.  Hygienic orbital autogenous welding of 316L SS (0.065 inch wall thickness) with purge gas 90% nitrogen 10% hydrogen

    Posted 07-02-2022 02:50 PM
    Hello,

    Does anyone have experience to share with the GTAW autogenous welding of austenitic stainless steel (316L in this case, wall thickness 0.065 inch) using 90% nitrogen 10% hydrogen (Formier 10) gas as purge gas. The shielding gas is Argon 4.8.  Our welding specifications typically require 99.998% argon for both purge and shielding gas and specifically do not allow the use of nitrogen as a purge gas. However, I am seeing hygienic stainless steel fabricators who use Formier 10 as the purge gas.  Do you have any corrosion resistance tests or metallurgical evaluations comparing nitrogen versus argon as the purge gas in austenitic stainless steel?

    thanks,
    Kim

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    Kim Jackson
    Welding Engineer
    Fluor
    Greenville SC
    8645171729
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  • 2.  RE: Hygienic orbital autogenous welding of 316L SS (0.065 inch wall thickness) with purge gas 90% nitrogen 10% hydrogen

    Posted 07-03-2022 10:38 AM
      |   view attached
    I particularly don't like to use nitrogen as a purge gas, because I'm more conservative person and I only see economic advantages, but an old paper is attached that says that there is no difference between argon and nitrogen for austenitic stainless steel, except for the stainless steel stabilized.  Good reading, and then I'd like to hear what did you think?  and if possible I would like to hear the experiences of others.
    BR
    Guber Guerrero 
    Welding engineer 





  • 3.  RE: Hygienic orbital autogenous welding of 316L SS (0.065 inch wall thickness) with purge gas 90% nitrogen 10% hydrogen

    Posted 07-03-2022 10:49 AM
    Hi Kim:
    I have nothing to sell but we do have radical welding technique (autogenous, no root weld, no stress riser, NOT friction) that could resolve medical welding issues.
    Technique falls under ASME IX, code case 2799. Repeatable, automated and no rework. Also zero toxic emission. I know, big claims but on the level.
    Presented to MTI in Orlando March 2022. Have presented to Nuclear (ANS) in DC. Technique is not rocket science. Everything we use is off the shelf but arranged differently. IPs+++.
    It works.
    Sincerely
    Paul Cheng
    FuseRing.com

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    Paul Cheng
    Inventor / Founder
    FuseRing.com
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