Welding 6 inch pipe

I am taking a Pipe Course and we are working on 6 inch Sked. 80 pipe.
I am using 6010 1/8 for root and 7018 3/32 for filler.
Right now I am in the 2G position and wonder if any "old pro's have
some tips for a novice Pipe welder.
Gary
Reply to
Gary
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I am not sure how your practice is set up. I used to get myself three or four pieces about six inches long, bevel prep both ends and gang them together to give me at least three roots to practice on at one time. The land and root opening is particular to each person. Find what you like and be consistent in your preparation. If you fit a joint and the gap varies over a sixteenth as you go around it will be exciting times for you. I take a large grinder first on the end of the splice then draw file the land checking to see that it is the same width all around. Matching it to a 3/32 rod is a good way. When I have welded the suckers up I take them over to the torch head and burn out the weld only leaving most of the pipes to put together again. I can then cut the weld rings and do nick breaks on them. When I get sound breaks with no porosity, slag or cold lap I know I am ready for testing. The root pass is for closing the joint up. The next pass, your hot pass, is the key. You should be running so hot that you have a lump in your throat thinking you are going to open up a gaping hole in your root at any moment. Hot and fast is important in order to get a flat bead with no notching at the edges. Keep all your fill bead flat and finish about 1/6 shy of the joint edge on both sides. At that point run your caps around using the edge of your prep to guide you. Excessive buildup will prevent you from even being allowed to cut out your coupons. And of course practice practice practice. Randy
I am taking a Pipe Course and we are working on 6 inch Sked. 80 pipe. I am using 6010 1/8 for root and 7018 3/32 for filler. Right now I am in the 2G position and wonder if any "old pro's have some tips for a novice Pipe welder.
Gary
Reply to
R. Zimmerman
Fit is critical...especially when your starting out. Make sure you keep your root evenly spaced and that you practice with the proper root gap until you feel comfortable. Changing the root gap by 1/16" will slightly change what is required for your travel speed and dwell time on the root.
When you finish one rod or run (hopefully about a quarter of the pipe diameter) make sure to slighty "piggy back" your re-starts so that the bead is fused thoroughly at bead connections inside the pipe. No it may not leak, but at some point you will probably have to pass a pipe certification and these small imperfections will fail you.
Patrick
Reply to
PROFESSORLITE
Do at least one test coupon that has 8 tacks in it, instead of 4. Getting the tie in to tack welds is one thing that most people have trouble with, yet most don't like to practice it.
If you are going to feather out your tack welds, make sure you do it _completely_. I would rather not feather at all, than do half a job. A hacksaw with two blades installed makes a good tool for feathering tacks.
Be fussy with your fit up. Cut, grind, then finish with a file. When you put the coupons together, there should be no light visible, and the land should be even all the way around. Rotate one half to minimize hi-lo. Getting the fit up right is probably the easiest way to get it right, as this part of the test is not as time dependent as the rest of it.
Last, IMO, this is one task that you need to train your body as well as your brain. There is too much going on too fast for your brain to do it all alone. It needs a bit of help from the rest of your body, in order to react appropriately, at the right time. The only way to train your body, is to practice.
Reply to
Wayne Bengtsson
I like 3/32 gap. Feather the tacks, if that's allowed. (It wasn't in my course, but is on my job.)
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Reply to
The 70's
Learn to get comfortable, you can do better work when comfortable and not straining. And if you do this for a living you don't want to spend all day in a bind. Also work on burning the whole stick of rod, or as much as possible. That gives you fewer starts and stops, and makes you faster. Bend the rod, back by the stinger, if it helps to put yourself in a good position. Like everyone said, practice a lot. If you intend to weld pipe for a living you will be testing on a regular basis, and your work will see pretty harsh inspection and scrutiny. So's you might as well learn to enjoy it !
regards, JTMcC.
Reply to
JTMcC
Several folks mention fit, I've got no problem with getting as good as fit as possible, within reason and in a timely manner, for a test but you ought to practice with marginal to poor joint fitup as that will be somewhat common in the field and you will be expected to take it in stride.
JTMcC.
Reply to
JTMcC
Thanks for the information. I used it all. I am now on 6G and it is definiteley interesting.
The fit-up is indeed critical as is the feathering of your tacks... thanks to all....
Gary
Reply to
Gary

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