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Reg
07-02-2010, 05:10 AM
I have a friend who installed 184 feet of water line by joining 100 ft rolls of 3/4" polyethylene underground with the barbed joiners and hose clamps. He told me that initially it would not hold together after applying pressure and that each time he thinks he has it repaired, the joint fails within a few days. I have no experience with polyethylene, but I found a few threads on here that mentioned the technique of heating the pipe carefully to insert the barbed connector, installing two clamps (opposed) per side, the torquing them correctly after the pipe cools.

I have not seen the installation, but he told be he abraded the pipe to get more "tooth" in an effort to get more grip on the barbs. Could this be a problem? I am not sure if he was aware of the techniques described above. Any advice is greatly appreciated.

Wally Hays
07-02-2010, 05:36 AM
Yes, mild heat, double, opposed clamps but most important is to use either a brass or stainless steel barb coupling, no plastic crap. And, do not "abrade" the pipe in any manner, inside or out.

jimbo
07-02-2010, 06:45 AM
You said he torqued the clamps! You cannot get a proper connection on this with a screw clamp. He really needs to get the proper CRIMP - type clamps.

180' is a little long for 3/4. He may have pressue loss issues.

hj
07-02-2010, 07:14 AM
MOre important, what is the pressure on the line? If it is blowing apart, he may have too much pressure and need a PRV at the source. If he has extreme pressure a 180' 3/4" line may work, but normally it would be marginal at best.

Wally Hays
07-02-2010, 07:48 AM
I doubt that any submersible pump would generate enough pressure to blow apart a properly made barb joint. Hell we routinely set pumps at 500' or so on a barb fitting and it's got to have a hell of a lot more torsion on it than any pump could deliver.

Reg
07-02-2010, 08:08 AM
MOre important, what is the pressure on the line? If it is blowing apart, he may have too much pressure and need a PRV at the source. If he has extreme pressure a 180' 3/4" line may work, but normally it would be marginal at best.

This is connected to utility water, not a well or irrigation pump. I asked earlier about a pressure reducing valve at the meter, but he indicated it did not have one.

Thanks for everyone's input and assistance. If he hasn't got it resolved by the time I leave work, I plan to go give him a hand.

Gary Slusser
07-02-2010, 05:53 PM
His roughing up the inside of the pipe is the problem.

He needs to remove all of the pipe reusing the clamps if they will fit the 1" 160 or 200 psi rated pipe he should have used and needs to replace this damaged pipe with.

He needs to use SS fittings for underground, otherwise sch 80 pvc is the best choice above ground. And he needs to buy a 200' roll of the new pipe at a pump or plumbing supply house so there are only two fittings, one on each end and then he doesn't have to have any underground.

BTW, PE pipe has been used on the east coast for going on 60 years for both city water service and well water systems. It can't be beat if you pay attention, follow directions and do it right.

Reg
07-03-2010, 06:12 AM
Thanks everyone for all the information and suggestions. I passed all of this along to my friend.

ballvalve
07-04-2010, 09:56 AM
Pass along to your friend that a tea kettle of very hot water is the only method approved by the pipe MFG. for heating the pipe enough to make it go over a properly sized barb fitting. We are talking about 160 or more PSI PE. Tighten the clamps with a nut driver when hot and tighten them the next day also. Use a brass barb for a critical joint hidden somewhere. Better yet, i always put a hose bib at those joints as a marker, or a metal stake if you are in cold country.

Dont get the pipe so hot that the clamps dig into the plastic. And use 2 of them. Roughing up the inside of the pipe is not needed but not a defect. Sanding the cheap plastic fittings to take away the barb misalignment from poor dies is more important.

Gary Slusser
07-04-2010, 04:02 PM
Pass along to your friend that a tea kettle of very hot water is the only method approved by the pipe MFG. for heating the pipe enough to make it go over a properly sized barb fitting.
That isn't true for the brand I used. There are a number of approved methods.


We are talking about 160 or more PSI PE. Tighten the clamps with a nut driver when hot and tighten them the next day also. Use a brass barb for a critical joint hidden somewhere. Better yet, i always put a hose bib at those joints as a marker, or a metal stake if you are in cold country.
You do not want to tighten clamps when the pipe is hot, that deforms the inside of the pipe. And who is going to wait 24 hours to tighten the clamps again!

You wait the few minutes it takes the pipe to cool to room temp and use the torque wrench made for the pipe clamps and don't over tighten the clamps.



Roughing up the inside of the pipe is not needed but not a defect. Sanding the cheap plastic fittings to take away the barb misalignment from poor dies is more important.
Roughing up the inside of the pipe will cause leaks with any type of insert fittings. I've never seen any bad insert fittings and for 18 years I bought and used many of them. I've never heard of anyone other than you that has seen any.