Hi to you guys out there, last week,a copper welding rod was mistakenly used for a ER 70s-2 to weld a butt joint on a 4" A 36 ,sch.40 carbon steel pipe.The pipe carries water at 60 psi,(30 deg. temp.) and the TIG welding process with argon gas was used.can this weld be sound,if not,why not? My argument was,since brass holds on mild steel,copper should also.what are you guys take on this one.
I know that they recommend using silicon bronze for some sheetmetal applications and what I have used of it has worked really well. I think that you should be alright if it was silicon bronze, but if it was pure copper I dont think it will work because pure copper dosent stick....like when you use a copper backup bar.
Many different materials can be joined by welding. Metals of various strengths can be joined and the welds may be completely fused however that does not make them sound. I would seriously question the quaility of the weld and its ability to function properly regardless of how well it "sticks".
My opinion is cut it out and do it with the correct filler material.
There's my opinion :)
Have a good day
G Austin
http://www.weldinginspectionsvcs.com
copper melts at a much higher temp than steel...also, i've never heard of copper being a part of an alloy mixture for any grade of steel. so, i don't think the weld will hold up under pressure.
Copper actually melts at a much lower temp than carbon steel. The reason it wworks well as backing to support a weld isa because it has the ability to absorb the energy better than any other metals.
The thermal conductivity of copper is the property which makes it appear to melt at a higher temp.
Good day
G Austin
http://www.weldinginspectionsvcs.com
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