The best way to setup to shield with Argon

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What is the best way to setup to shield the back side of an open SS TIG weld? I’m trying to be as close to sanitary as I can because the fermenters I am welding are used in Brewing. I’ve seen the videos on how to use aluminum foil and a second gas source to shield the backside. I don’t mind buying another flow meter but I’m not seeing how I can hook up the second flow meter to the same bottle is there an adapter made for this? How are those of you that are doing sanitary welds handling this? What’s the “right way”?  If I purge the fermenters with argon and close the top off will that be enough to prevent oxidation? They are 16 gallons each so it will waste a lot of gas, but I just want to get these little 4” welds of .050 SS real clean, and I need to weld from the outside of the fermenters.ThanksCharlie
Reply:I believe you can get T's from Western designed to allow 2 regs to be attached to one cylinder.http://www.westernenterprises.com/en.../PDFS/wi28.pdfI think the one you would want is a "T-92" but I'd double check with the guy at the LWS to be sure that the outlets will allow you to attach 2 regs to the adapter. I don't usually use those type of adapters, but I did get a bunch set up for O2 at one time like that from a manifold system we bought used.. Clearance might be an issue depending on what regs you have. If nothing else I know Western sells all the parts to make a HP manifold that will let you do this. I use their CGA 580 parts to make fill adapters. Just be sure that all the fittings are rated to at least 3000 psi if you go this route. You can not use standard pipe fittings. Usually since I have to order the CGA fittings anyways, I just have the LWS order the HP fittings direct from Western when they order the adapter parts. Attached ImagesLast edited by DSW; 11-18-2011 at 10:50 PM..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:You can get a tee that will screw into your argon tank and then 2 regulator/flowmeters can screw into the tee. The tee has CGA- 580 fittings. The Western Enterprises part no is T-92. It should be available at any welding supplier, or at a website such as weldingsupply.com . The easiest way is probably to purge the whole vessel, but there's nothing wrong with getting creative with a purge dam either! If you purge the whole thing, you'll need to block off all outlets, and leave a small(1/8" or so) vent at the highest point to let the air out.
Reply:Thanks the T-92 looks like it should work. I was concerned about the air leaking in around the fitting I’m welding from the outside. I might be able to make a seal with a upside down metal funnel on the inside and keep the gas on while I weld it. Was hopping to hear how a “sanitary” SS TIG weld done by someone who does them for fermenters as that whole concept is new to me.
Reply:CharlieC,It's called using your head.Doesn't take a rocket scientist to design a simple "purge box" that is affixed to the inside of the fitting.  Can be made out of wood, aluminum, etc.  Hold it in place with a simple pressure device (wood in a slight bow) and seal the edges with high temp tape.I could throw together a simple aluminum purge box for a kettle shape in less than 30 min.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Found some great info from this guys one post: http://weldingweb.com/showpost.php?p...5&postcount=28 I'm also working on a ss tower for my ocean boat so I’m going to need to get used to the TIG shielding process. In the past I only used TIG on Aluminum. The high temp tape idea is good. Thanks for the pointers
Reply:Those tees work very well. We used many of them as it's much nicer than having damage to one side of a dual flowmeter take it out of service.
Reply:These are my setups for tig welding with dual Smith flow meters using one regulator. The disconnects are on the portable setup.I used armaflex foam type insulation to make the purge plugs from for tubing with a homemade cookie cutter setup.On a tank fitting I used aluminum foil, heavy duty type and masking tape, just place the tape far enough away that the heat doesnt get to it too quickly.I had a fitting setup to purge from the outside of the tank thru the fitting I was installing and used the aluminum foil and tape on the back side with about an 1/8" hole punched in it for a vent, and about 5 cfh on the flowmeter.The block on the regulator is a homemade tee made up for this application, the different  length nipples are so that it can be screwed together.mike sr