What most people don't know is that you are better off doing hot taps when that product is flowing. It cools your bead as your are welding. Also, there is no oxygen in the line = no boom boom!
If you are working on a hot line that is open ended at your weld but not in service, make sure the other end is shut in. no oxygen = no boom boom!
If you are working on an out of service hot line that is open ended on both ends, well..........keep your hood far enough back that the flames don't melt the plastic before you tie in the root! lol
As far as the rod - on pipe, I would imagine downhill rod. On weld-o-lets and nipples, I would imagine either or; downhill rod, or low hy-or both.......
Good luck, and don't be scared. AND charge accordingly on hot taps! I charge 110 bucks per inch.
Remember this: no oxygen, no boom boom. Seriously that's all there is to it!
By james1 
Date 07-25-2008 00:54
Edited 07-25-2008 00:58
How about asking for all thier procedures bebore you start.eg lam test,, cooling rate test,do you require someone trained to run rosebud ahead of you with temp sticks, thickness test, rod requirements,rated fittings do they lower pressure which increass flow and chilling rate.. toe cracking and hardness are what you don't want here.. anything I forgot please fill in ....these things may help may you look like a pro
James
The gas company will have a procedure for welding the hot tap. My guess it that you will take the API 1104 test, a branch weld and a butt weld. You will weld the hot tap like you weld the branch. Use the same rods the gas company requires for the test.
Grind the pipe shiny where the tee will sit. I don't ever weld cold. You want a heat you can control. But particularly on the first pass, direct most of the arc on the tee. Just let the puddle lick the pipe. Then, I like to run a hot pass that smooths everything out and appears that that the weld is completly fused to both the tee and pipe. On most sizes I run two more passes. In other words a two pass cap. Do not try to weld cold. Just have a managable heat and let about one third or one half of the puddle tie in to the pipe. On a scap piece of pipe, try and see how hard it is to burn through. Very few people are killed doing this.
thanks that helps
got any pointers on the branch
zach
You will be welding to API 1104 Appendix B. In addition to the butt and branch you will have to do the sleeve test. This is outlined in API 1104 B.3. This test is fairly involved if done properly. Most pipeline companies require anything that welds to the pipe in service to be welded with E7018 UH
The tacks on the side of the sleeve MAY be done with 6010 but everything else is LH.
The line MUST be flowing as this is what keeps the weld cool. Hot taps are not that dangerous. The weld area has to be UT examined and it must meet certain t-min requirements.
Now welding sleeves on corroded pipe is something else. wahooo
BABRT's
Are we talking about a 12" branch test? Sheeeeeit! Done a few of those!
Dont worry. If you are a hand you will do just fine. Most times that I do that test, they don't even test it, (not the way they should)!
They just want to know if you can do more than dance - know what I mean?
I agree with bigK
Everything should be inspected before the "tap".
Sometimes the line is washed out on the bottom, (most times), and you have to take that into consideration. Burning thru a thin spot sucks!
That's when you're gonna get burned, if the line is flowing.
i have fixed leaks and things like that no big deal, but i have never welded one with pressure no it befor and i was just wondering if there was any special things that i need to do or watch out for
but sourdough thanks for your help
oh more product better or worse
thanks zach
Good fit is key for me on the branch. Try to get a pattern to lay out the saddle. I have layed them out by the Pipe Fitters Blue Book, but a good pattern is a real time saver. Make yourself a copy. If possible make the fit ahead of time when you have plenty of time and no pressure. Grind the bevel much bigger at the deep part of the saddle, not much at the points. A little land is a good idea. Tack the saddle part first, the points last. The points will always close in. Little wedges are handy to get a good fit on the points. Try for a consistent gap. Also. plan your tacks so they are not where the straps will be cut out. It is handy to have a remote or someone to adjust your machine for the variance you might have in the gap. When you cut out the hole in the branch, I like to leave 1/8 or so inside of the saddle.
I always swear that I will stay current with my qualifications so I won't have to go through the whole thing again. But have let it go from time to time. Hope that helps.
PRODUCTION BABY!
If that company has a bunch of product moving, chances are you will be THE MAN!!
I did more than 170 well hook-ups last year, and many-many hot taps. The outfit that used me kept me busy even tho they didn't have much going on after gov. stipulations. They don't want to lose their "pet" welder!
You will learn just how important a good welder is after time!
Don't do anyone any favors!
