Opening PVC Pipe Joints Without Total Destruction?

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SteveHGraham
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Opening PVC Pipe Joints Without Total Destruction?

Post by SteveHGraham »

I am in the process of trying to install my new sprinkler pump. All the stuff that attaches to it directly will be PVC. Farther away, it turns into iron.

Here's my problem. The PVC is not threaded. It's glued. The reason for this is that only skilled, intelligent tradesmen know how to thread things, and I am in South Florida, where no skilled, intelligent tradesmen exist.

There is a glued joint I would like to open without destroying everything. It's 2" pipe with a remnant "collar" from an old fitting, opening downward. I want to get the collar off and keep the 2" pipe.

I found a Youtube video that shows a guy removing pipe from inside a PVC fitting. He put cement inside the pipe and set it on fire. Thirty seconds later, he blew it out and yanked the pipe out. The glue and inner pipe had softened.

I have a joint just like the one in the video, but it opens DOWNWARD, and the collar of waste is OUTSIDE. The video joint opens upward, so the flame has a place to go. In a fitting that opens downward, it will be hard to avoid melting everything, because the flame will rise toward the joint.

I read online that an ordinary hair dryer will heat a PVC joint enough to break it loose. Has anyone here tried this? I can just see myself out there heating the pipe for three hours and getting nowhere.
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SteveM
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Re: Opening PVC Pipe Joints Without Total Destruction?

Post by SteveM »

I might even pay to see you sitting there for three hours with a hair dryer :-)

You might want to upgrade to a heat gun - the kind that takes paint off.

Steve
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10KPete
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Re: Opening PVC Pipe Joints Without Total Destruction?

Post by 10KPete »

A carefully manipulated propane torch has always been my weapon of choice for working PVC. Just be patient and don't get the torch too close!!

Pete
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juiceclone
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Re: Opening PVC Pipe Joints Without Total Destruction?

Post by juiceclone »

"Correctly" glued pvc joints are actually fused/melted? together and can be stronger than the pipe itself. most likely won't come apart in any usable condition. Although sprinkler sys don't usually run with much pressure....
Yeah ....I know, live in S Fl tool.....
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SteveHGraham
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Re: Opening PVC Pipe Joints Without Total Destruction?

Post by SteveHGraham »

I tried the hair dryer, which was pretty funny, unless you were the guy doing it. Nothing happened.

The heat gun sort of loosened the pipe up. I was able to carve bits of the outer pipe off, but I'm not sure I want to spend two or three hours continuing that process.

The MAPP torch was too much.

I took a joint I had already cut off, and I put it in a saucepan full of boiling water. Absolutely nothing happened. That tells me there is no hope of getting the outer PVC to slip off. Heat gets it to where I can peel it off clean with the knife, but that's about it.

I hate everyone who does PVC plumbing now. Whoever installed this thing knew the motor would eventually poop out, and that someone would have to change it. They should have spent half an hour preparing the pipes for easy removal.

This kind of reminds me of my dad's boat. The refrigerator died, and we called the manufacturer to find out how to get it out of the galley. They said they BUILT THE BOAT AROUND IT.

I think there is enough of the inner pipe available to allow me to use a slip union. I plan to give that a shot tomorrow.
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10KPete
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Re: Opening PVC Pipe Joints Without Total Destruction?

Post by 10KPete »

I'm with you, Steve. Any one who doesn't provide the necessary screwed joints to allow future servicing should be slapped, at a minimum!!

And don't get me started on boat builders.....

Pete
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Russ Hanscom
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Re: Opening PVC Pipe Joints Without Total Destruction?

Post by Russ Hanscom »

I have successfully salvaged a lot of PVC fittings; here is the process I use.

Use a hacksaw blade, Dremel saw blade, or similar to make multiple cuts in the piece to be removed, cut deep enough to reach the glue line but not deeper. Start with a set of cuts that are 1/4 - 3/8" apart and use a sharp chisel at the joint; the narrow strip should pop off, or at least most of it. Depending on the quality of the glue joint, you may be able to remove successively wider strips. After the large bits are gone,. use a sharp chisel, knife, or file, as appropriate to clean up what ever is left.

Good luck.
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liveaboard
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Re: Opening PVC Pipe Joints Without Total Destruction?

Post by liveaboard »

I just chop away the PVC and put in whatever new PVC it takes to put it back together. The stuff is cheap.
Sometimes I've used screw together unions to facilitate maintenance, but the union costs more than the rest of the piping.
I have taken apart pvc by heating; it takes a LONG time for the heat to bleed through to the joint. The next time I tried, it didn't work.

Just saw it apart and put new joints while reassembling, without regard to the used bits you throw away.
I know this goes against our creed....
You could mount female parts on your lathe and cut the old tubing out so you can re-use some parts.
Just don't count the hours and avoid any thought of cost-benefit and the rest will be ok.
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SteveHGraham
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Re: Opening PVC Pipe Joints Without Total Destruction?

Post by SteveHGraham »

It's not a matter of cost. When you have a lot of joints and valves very close together, you can't just chop out one thing and replace it. In order to replace one part, you have to redo everything. I would have to replace a whole bunch of joints and valves, in a tight space.
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Russ Hanscom
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Re: Opening PVC Pipe Joints Without Total Destruction?

Post by Russ Hanscom »

I understand the situation, that is why I worked out my process.
Patio
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Re: Opening PVC Pipe Joints Without Total Destruction?

Post by Patio »

I am an electrician by day. I too have had success undoing joints. I use the same method Russ uses. I cut slits up the joint, parallel to the axis of the pipe. Then I use a wood chisel, starting at the joint, to separate the outside bell end from the inside pipe. I have even used a screw driver to make the cuts and remove the outside pipe, when in the field with out proper tools. It may leave the inside piece of pipe in rough condition that may require a little shaving with a file or knife to smooth the surface for the new fitting. As others have mentioned the glue melts the two pieces together, so when installing the new fitting, use a good amount of glue to help smooth the rough pipe. Also when gluing, give the joint a twist as they go together, it helps seal the joint.
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SteveHGraham
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Re: Opening PVC Pipe Joints Without Total Destruction?

Post by SteveHGraham »

The joints are no longer a problem. Now I have to fasten this pump down.

The pump is in a shed with a concrete floor. There will always be water issues due to the grade outside, so I can't just zip over to Home Depot and get galvanized anchors. I'm thinking I'll use 5/16" stainless screws and lead lag shields, set in the floor. Not the sturdiest installation ever, but at least it won't rust out in six months.
Every hard-fried egg began life sunny-side up.
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