welding CDA 360 brass pipe

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I have a customer that would like some cylinder fill manifolds joined with tig instead of being brazed with BaG7.  Does anyone know what filler metal to use for this?  I would appreciate the help.
Reply:Checked www.copper.org to be certain.  They do not recommend any fusion welding process for Brass alloys.  Only soldering or brazing.  I think the reason being that the heat of the arc is more than hot enough to vaporize the Zinc in the alloy.  So, if you TIG weld those fittings, you'll burn the zinc right out of them, altering the mechanical properties of the metal in the weld and HAZ.  Since zinc improves the strength of the material, this is not good for pressure pipe.You'll also have to worry about the zinc fumes generated.  All in all, I do not recommend TIG welding.That said, I have patched some cast brass parts by TIG welding.  I used pure copper wire, from some solid wire romex I had in the shop.  I did not guarantee the repair, I I wouldn't recommend this procedure for your application.  But for cosmetic repairs, it can be done...Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:thanks,i appreciate the response.  There is a local mechanical contractor that did some with some Bcup 5 brazing filler with good results, but they aren't willing to share anymore info than that.
Reply:Can you use Stainless? Most of our HP manifolds (3500-4500 psi) are assembled out of HP ss tube and Swageloc fittings, but we do have one that we got used that was rigid ss pipe and tigged.
Reply:no, it is for oxygen service and the velocity is over 400 ft/sec @ 3200 psig2 Trailblazer 302's2 HF251-D1'sDynasty 200DXLincoln Powermig 140CHypertherm Powermax 30Airco Torches out the a$$
Reply:You might search around and see if AWS or ASME or some other professional organization has a welding/brazing procedure that you can use.  It might cost you some money to get the pre-qualified procedure, but that's better than guessing.  Found this with a little searching.  It's what you're looking for, except it's for a different base metal.  You need something like this for CDA 360...  Maybe someone else can point you in a better direction...http://www.copper.org/applications/p...oced_specs.pdfBenson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:Thanks for the lookup.  I already have the brazing procedure and have certified with it through the AWS and NFPA.2 Trailblazer 302's2 HF251-D1'sDynasty 200DXLincoln Powermig 140CHypertherm Powermax 30Airco Torches out the a$$
Reply:Cryowelder if you don't mind my asking whats it for? The reason I ask is that I was trained in the dive industry for O2 service, and while its not generally recommended, many in the field use SS for O2. Right or wrong, I won't debate, I have read the U.S. Navy's opinions both for and against SS for O2 and they don't seem to have a definitive answer. Monel, brass, SS they seem to recomend and disaprove of all of them at one point or another.We would frequently fill O2 to 3000psi but seldom any higher. IIRC O2 goes liquid at just above you pressures, and becomes highly reactive so I can understand why SS might be a poor choice. From yor sig I wonder if you work with liquid O2.Having been involved in an O2 fire, and personally knowing someone who was killed in an O2 tank explosion, I can certainly understand the need to make sure it's right. Here's a thread you might find interesting. It shows the aftermath of the O2 fire.http://weldingweb.com/vbb/showthread.php...hlight=boosterAs I help to train those who work with HP O2 I am always on the lookout for more info on the subject. Thanks.
Reply:DSW I am working on some gas cylinder fill manifolds for my LWS.  I am building one pure O2, one mix line with O2, AR, GAN, and CO2.  The other is a pure GAN and AR.  I work with liquid oxygen everyday and use the CGA as well as some of the other industrial gas compnay standards as refernce with regards to material selsction.  I am also involved in training fire departments and other emergency response personnel in the handling of all these materials especial liquid oxygen and hydrogen.  The rule of thumb that we use is if the velocity is over 300ft/sec then we try to use either brass or monel depending on the specific system.2 Trailblazer 302's2 HF251-D1'sDynasty 200DXLincoln Powermig 140CHypertherm Powermax 30Airco Torches out the a$$
Reply:DSW I will look through some of my safety training material and see if I can come up woth some pertinent info for your application2 Trailblazer 302's2 HF251-D1'sDynasty 200DXLincoln Powermig 140CHypertherm Powermax 30Airco Torches out the a$$
Reply:Thanks I appreciate that. As I continue to learn tig I'd love to be able to build a nice manifold for my personal gas bank. The 1/4" SS tube and swagelocs + braided SS flex lines work fine but isn't very pretty or elegant. I'd love to do a nice one in brass or SS rated at 4500 for air, and a 2nd one for O2 or He, and drop it all into a nice neat pannel with valves and gauges and set the whole thing up for travel.I've never handled liquid O2 myself, although I do know one shop that uses it for mixing thru a blending stick and compressor vs partial pressure blending that I am more familiar with. I'd love to learn more.I'd love to see some picts of the compleated manifolds or other gas  projects of yours from the past and see if I can pick up a few tricks / suggestions.
Reply:360 has both lead and zinc in it. Makes it really nasty to weld- the zinc and lead have very low melting points, they evaporate into gas, leaving bubbly copper.Silver Solder is probably best.I have had success with tig welding with silicon bronze filler rod- it snap, crackles and pops while you are tig brazing it, but you get air tight, although not awfully pretty, brazes at the end.
Reply:Originally Posted by cryowelderI have a customer that would like some cylinder fill manifolds joined with tig instead of being brazed with BaG7.  Does anyone know what filler metal to use for this?  I would appreciate the help.
Reply:Everdur is one companies trade name for silicon bronze, which is the same rod I use for brass.
Reply:DSW I reccomend looking into a central round manifold block and pigtails to keep it simple for a portable filling rig.  Some aluminum and some panel mount valves will do you good too.  Check out cryovation, they have some premade portable filling rigs for welding cylinders the you could use for some ideas.2 Trailblazer 302's2 HF251-D1'sDynasty 200DXLincoln Powermig 140CHypertherm Powermax 30Airco Torches out the a$$