WELDING PIPE TO FITTINGS
WELDING PIPE TO FITTINGS
(OP)
so I am welding a triclamp fitting onto a pipe. Now I was wondering, is it standard practice to fillet the edge of the pipe for welding the flat face of the ferrule? I guess in general when you weld pipe would you chamfer the edges around like this normally to do a bevel weld?





RE: WELDING PIPE TO FITTINGS
RE: WELDING PIPE TO FITTINGS
Normally we do Tri-clamp fitting butt welds autogenously using an orbital (robotic) welder. The ends are prepared square, not bevelled, and the weld is completed without filler metal.
If you are welding with filler metal, you'd need to ask a welder which technique works best on thin sections like this. The issue isn't really how to get a decent weld, it's how to generate a weld which doesn't have an unacceptable surface finish on the ID such that you'll have to spend a lot of effort grinding and polishing the ID when you're done welding.
RE: WELDING PIPE TO FITTINGS
At 0.083" and heavier I more often see a slight bevel and filler used.
An alternate to both is to use weld rings, but that is another issue all together.
But if this is for hygienic service then the real issue is the quality of the ID surface, you must have 100% uniform penetration with minimal excess metal.
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P.E. Metallurgy, Plymouth Tube
RE: WELDING PIPE TO FITTINGS
RE: WELDING PIPE TO FITTINGS
RE: WELDING PIPE TO FITTINGS
Practice. You need the right current and speed balanced with wire feed rate.
A skilled welder can probably develop a protocol with 5-6 practice runs. These can just be pipe to pipe.
Is this stainless steel?
What grade? Look very carefully at the CMTRs, variation in S will have a large impact on metal fluidity and may require some compensation.
Try autogenous welds first, they are much easier.
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P.E. Metallurgy, Plymouth Tube
RE: WELDING PIPE TO FITTINGS
RE: WELDING PIPE TO FITTINGS
RE: WELDING PIPE TO FITTINGS
"but it would be made out of China so I cant just walk in and check, but I want the drawings as accurate as possible"
I have spent the past 15 years working in Quality Control in Asia ( China, Thailand, Vietnam, Malaysia and the Phillipines)
and I know if people purchase things from Asia they are doing it because it is cheap but they don't realise unless you have expatriate supervision you have no idea what sort of quality you are going to get.
All the cost savings from fabricating in Asia are eaten up pretty quickly when you have major rework required in the country of destination (eg. Bay Bridge in California).
Get on a plane and make sure you are getting what you ordered,
Cheers,
DD