Min pipe size to butt weld
Min pipe size to butt weld
(OP)
Hello Gentlemen,
I'm sure that has been addressed somewhere in the annals of eng-tips.com, but I couldn't locate a thread on it. I have a simple question - Can I expect a contractor to successfully butt weld 1" SCH 80 CS pipe?
I'm working for a client that allows this in their piping specs, but I hesitate because I've never seen this allowed by anyone else before. I always understood it to be bad practice to buttweld any piping less than 2" size under normal circumstances.
Thanks!
I'm sure that has been addressed somewhere in the annals of eng-tips.com, but I couldn't locate a thread on it. I have a simple question - Can I expect a contractor to successfully butt weld 1" SCH 80 CS pipe?
I'm working for a client that allows this in their piping specs, but I hesitate because I've never seen this allowed by anyone else before. I always understood it to be bad practice to buttweld any piping less than 2" size under normal circumstances.
Thanks!
Tolerance is the virtue of the man without convictions -GK Chesterton





RE: Min pipe size to butt weld
You wrote,
"Can I expect a contractor to successfully butt weld 1" SCH 80 CS pipe?"
I say Yes! It can be done, but.
It depends on the type of plant/System/Commodity/NDE Requirements.
I worked on a Plant that required butt welded pipe on all systems, large and small.
I also worked on a plant that required Butt welded joints on all size piping of SS systems.
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Before I spent the time designing those systems I took a Welding Class where I did butt welding on 1" and 3/4" piping. I had to pass the NDE and destructive testing of all my welds.
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It can be done, but the down side is the complexity in doing the actual weld of those sizes (in the shop or in the field) and the cost of the NDE that was required.
Sometimes its possible to do all the right things and still get bad results
RE: Min pipe size to butt weld
Although it may not be as common, it can be done. During my days with a pipe fabrication shop we also had clients that required piping under 2" to be butt welded.
ASME B16.9 covers sizes all the way down to 1/2" NPS.
RE: Min pipe size to butt weld
RE: Min pipe size to butt weld
Depends upon the requirements of the service?
RE: Min pipe size to butt weld
If it's carbon steel, is there a service where it makes sense to butt-weld carbon steel lines that small? Doubtful. The situations do exist, but they're rare. Generally everything 2" and smaller in carbon steel is socket welded. It's cheaper to do, and much more likely to be done right.
In corrosion resistant materials, butt welding at small linesizes is done to reduce the number of crevices and improve drainage to improve corrosion resistance. It also saves money on fittings- you don't want to buy huge hastelloy forged socket-welded tees and elbows for instance. There's a great deal less material in a butt welding tee or elbow. It's the same reason one uses lap joint flange construction in exotic materials.
RE: Min pipe size to butt weld
RE: Min pipe size to butt weld
RE: Min pipe size to butt weld
RE: Min pipe size to butt weld
RE: Min pipe size to butt weld
"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick
RE: Min pipe size to butt weld