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HDPE plug

HDPE plug

HDPE plug

looking to plug a couple of HDPE pipes

  • first one is an abandoned 4" line that will be cut and plugged where it enters the ground
  • second is used as a sleeve for two smaller lines and needs to be sealed at the end to prevent water or dirt entry.
I had originally thought that cement grout could be used, but with wide temperature swings / expansion and contraction of the pipe, it might not seal tight. I would like to avoid trying to use fused HDPE fittings. Is there another material that might work?

RE: HDPE plug

well, that might work for the abandonment if there is something out there that will fit and that can be buried and still remain watertight, but not for the sleeve

RE: HDPE plug

There is an expanding poly grout that uses the in-place moisture to stay expanded. Call Avanti

RE: HDPE plug

the sleeve is 6 inch DR21 and the smaller lines are 1 and 2 inch. All are fused HDPE

The expanding poly grout might be an option

RE: HDPE plug

Quote (cvg)

I would like to avoid trying to use fused HDPE fittings.

Can you explain a bit more? elctrofusion joints are very simple and need only 12V and will seal for life.

e.g. http://www.fusiongroup.com/product/electrofusion-f...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: HDPE plug

both of these projects are earthwork / concrete projects.

for the abandonment, there is no piping on the project and unlikely the contractor would have experience with the fusion process. I just need a good, easy way to seal the end, bearing in mind that I need some sort of sealing material that will handle the expansion and contraction due to high temperature variations (10f to 110f).

For the other project, the sleeve will be fused, however at the ends, there will be two small carrier pipes inside the sleeve and not sure how the ends could be fused using a plug. The sleeve will be either above ground or near the ground surface at both ends. Either a grout or sealer of some type to fill the annulus, or some sort of end plug to seal against water. Again, very high temperature variations (20f to 120f).
see detail

RE: HDPE plug

For the abandonment, the electrofusion caps are about as straightforward as it gets. Minimally prepare the surface of the pipe, stick the cap on, plug in the leads, scan the barcode on the fitting, and push the GO button. Provided they have access to a place that supplies/rents the fitting and machine, should be straightforward.

In the second case, how watertight does it need to be? How critical is the seal? Is it spray you are keeping out? Or will it be submerged?

To my knowledge, little if anything will bond to HDPE. So your options are fusion, or mechanical fittings. If it must be completely watertight, it seems like your only option is to transition into a junction box with a mechanical fitting, and out again with two other mechanical fittings. Otherwise, I think the temperature fluctuations are going to play hell with anything grout could accomplish.

If you just need to keep nuisance water out, then grout the entire annulus and do your best to protect the exposed end from exposure to water. Perhaps some hydrophilic waterstops and a concrete cap.

RE: HDPE plug

it will be totally submerged from time to time.

so, if I specify some sort of fusion cap on the end of the sleeve, could that be done? so far I have not seen any sort of fusion fitting that could accommodate the two carrier pipes.

i would like to avoid grouting the entire annulus, but that is certainly an [expensive] option

RE: HDPE plug

The fusion cap is only for your first scenario.

The second with the carrier pipes will require a concrete cap with hydrophilic waterstops; or a custom fabricated fusion fitting (you could maybe have one made for $,$$$.

RE: HDPE plug

so I am back to the expanding / hydrophylic poly grout which seems to be a good option for reasonable cost and could work for either location

RE: HDPE plug

Just buy a 1" and 2" fusion end cap and cut back the inner pipes as much as you need to and then cap them then cap the outer 6" pipe.

Note it depends on what market you're in, but commonly HDPE is sized in mm not nominal inch sizes so just make sure you know what you're buying. More than once people familiar with steel pipes try to order PE pipes using different nominal and actual diameters.

At it's most basic, all you need is a 12V car battery and some leads and watch for the little poppet to lift indicating that fusion has taken place or time the duration of the heating. So long as you've cleaned the outer pipe and it doesn't have dirt / grease etc, then it is virtually fool proof.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: HDPE plug

LittleInch, I believe cvg is capping the sleeve; but that the carrier pipes are not to be abandoned and will continue through the cap to terminate elsewhere.

RE: HDPE plug

well, that would work except that the two small pipes are active, under pressure and the outer one is just a sleeve. so no plugging and cutting back can be done. Driscopipe is specified in inches, I have not seen any sizing in millimeters. I am however having difficulty finding 1 inch size, so will probably just use 2 inch


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