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Discussion Starter #1
We ran about 200' of 4" black iron pipe with about 60 joints and 14 of them are leaking. Some of the threads are put together with Blue Block and Teflon, some of the others are Blue Block and wicking. It doesn't seem to make a difference which was used. Fittings were tightened with 48" wrenches so they are defiantly made up. Most of the ones we cut only went at best six of the nine threads into the fitting, some went all the way in, others only went three or four. I'm trying to figure out what went wrong here. I have a couple ideas.
Is Blue Block a bad idea on pipes this large? Just a bad idea in general? Last time I did pipe above 2" was a 3" gas line put together with plain old Megaloc. We had one leak on the whole line and it was because of a bad fitting.
How far should 4" black pipe make up into a fitting? Ideally it should be locked up on the last thread right? I'm thinking that the dies on the Ridgid 141 might be shot or something else on the threader is going wrong. Is their any way to tell when the dies are shot besides physical damage?
 

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had that happen with 1-1/2 black pipe. Did an entire house in the attic. Dies were bad.
 

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You gotta get pretty mean with 48's on 4". That stuff has to be TIGHT. We use tape and permatex teflon dope. Get ALL the cutting fluid off the threads or the pressure will chase the thinned dope out of the thread. The blu-block sucks. Any vibe or joint movement and you've got a leak.

Remember 3 threads showing when it's tight. No tears in the threads and screw on 2 turns before it gets tight by hand or the dies are wrong. NO OIL RESIDUE after threading. Don't tighten it till you think it's tight. Tighten it till you can't tighten it anymore.
 

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Are you using threaded cast iron (IPS) or threaded black steel pipe?

There is a huge difference.
Never thought of that. I ASSumed blk steel. Also, I don't know what fittings leaked. I'm guessing the ones that went all the way in where merchant couplings?
 

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We use GASOLA and usually thats all. I don't know what your piping, but we can't use teflon tape on gas. Check your fittings. We had problems once on a resturant and found out it was bad threads in the fittings that came out of china. Ever since I make sure we buy usa made malable fittings.
 

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Discussion Starter #8 (Edited)
You assumed correctly, it is black steel pipe. We did not thoroughly clean the threads, we just wiped them with a rag. Maybe that's the problem. In the future I'll keep the bottle of Spray Nine and some paper towels handy and see if that helps.
As for tightening them that's what we do, tighten until they won't turn anymore. We started out using 36" wrenches. I went and dug out 48" the next day because I didn't think that was enough.
I also don't like Blue Block for the exact reason you mentioned. Once it's hardened for a couple hours any movement in that pipe and you have problems. It's so easy to crate more leaks fixing the leaks we have now by not holding back correctly.
These are water lines, not gas. We are not allowed to use teflon tape or wicking on gas lines either. I have heard their is a special tape for gas which is approved but I've never seen it or used it.

edit:
One more thing. How deep do you guys thread 4" pipe? I'll do a thread count today and see exactly what it is. I think we are 15 or so threads deep. If we actually tightened it to three threads left sticking out we would be well inside the fitting and wouldn't that cause pre-mature wear on the pipe? When I said "made up all the way" I meant it made all the way into the fitting which is nine turns. The only ones that made up more than that are the factory cut threads on the nipples and lengths. Most of the ones we are backing out and re-doing now are making up somewhere between five and nine threads.
 

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If your using a 141 threader it has a start and a stop line on it. I think it might be 12 threads. Your bottoming out in the fitting before the taper hits the fitting much. 2.5" EMT conduit about 5' long makes a good cheater. It's light. Slide it on till it's tight on the tapered part of the wrench. You'll end up with 72" of wrench.
 
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Discussion Starter #10 (Edited)
Yup, it has the start and stop lines. I took a look today and it's threaded 15 deep. You are right, while threading it comes out probably nine threads or so passed the dies when it's fifteen threads deep. That is the whole depth of the fitting. Next time I'll try making some adjustments and getting a couple less threads on it. Most likely the problem here is a combination of everything mentioned, threads cut to deep, excess oil, and being under tightened.

We spent the whole day today re-doing it. Now we have nice clean threads and the fittings cranked with a 48" wrench with a 3' cheater bar. I'm nervous about fitting it up on Monday. Someone forgot to hold back and moved a couple fittings sealed with Blue Block two months ago. They're in a horrible spot as well, it would be two days of work to get to that fitting.
 

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Make sure that 141 is set on tapered threads. It will cut both nss and npt.

I use a can/dauber of clear pvc primer to remove the oil. Then wipe clean with a dry rag.

Teflon tape makes them go in deeper more easily.

When we run T&C pipe the journeyman I use weighs 300+. That helps more than anything. I tip the scales at about 180. It don't matter how strong you are if ya don't have enough a$$ to crank that wrench:)

It's been a few years since we ran run much T&C pipe. Used to run t all the time. Then we went to Vic:thumbsup: Now we run 4" sch 10 grooved with oil resistant doughnuts rather than 4" sch 40. A joint of 4" sch 40 is about all 2 guys can handle. Good luck!
 

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Discussion Starter #12
Make sure that 141 is set on tapered threads. It will cut both nss and npt.

I use a can/dauber of clear pvc primer to remove the oil. Then wipe clean with a dry rag.

Teflon tape makes them go in deeper more easily.

When we run T&C pipe the journeyman I use weighs 300+. That helps more than anything. I tip the scales at about 180. It don't matter how strong you are if ya don't have enough a$$ to crank that wrench:)

It's been a few years since we ran run much T&C pipe. Used to run t all the time. Then we went to Vic:thumbsup: Now we run 4" sch 10 grooved with oil resistant doughnuts rather than 4" sch 40. A joint of 4" sch 40 is about all 2 guys can handle. Good luck!
I didn't know that it could do both threads with the same dies. I'll check that out. That's actually what I ended up using. I tried the Spray Nine and paper towels. That lasted for one thread and I grabbed a can of PVC cleaner.
I've seen the sprinkler fitters using vicaulic. That is some cool stuff, we've never used it though. I don't know if it's even approved for a geothermal system. The architect specified black steel pipe. We tried to get him to use plastic or copper but we wanted black because a fire wouldn't damage it (go figure that logic out).
 

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Look into getting a set of chain tongs, or even two sets, I have a 5' and a 6' set for doing IPS pipe, I also have three different sizes of compound leverage pipe wrenches that work well when space is limited.
 

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Discussion Starter #14
Those are cool and would probably help out a lot but it's not my company and I'm still working on trying to get a new cordless drill, I don't think the boss man is going to spring for those.
 
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