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PVC expansion coupling?

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Jim greengo

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Ived used lots of them over the years,set it in middle of range when you install it.
Post a picture of the rest of what you're trying to do.
 

pattenp

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As said a picture is needed. Sounds like you may not have planned out the glue up to have some flexibility to slip joints together.
 

pattenp

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I think he's asking about using it to make up the connection between two points that are fixed with no flex to slip joints together, not using it as an expansion joint due to temp changes. I've also used them for expansion joints when coming out of the ground to a panel, but never have had to use one to make up a connection due to lack of pipe movement to slip a joint together. Can an expansion coupling be used for that reason? Absolutely.

Edit: You could ream out the barrier lip in a straight coupling and make a slip coupling for a lot less $$ than the expansion coupling.
 
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grounded-b

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Milwaukee, WI
Set the expansion coupling to mid-span. Measure distance between inside of pipe sockets. Leave this much gap between your two fixed conduits. Compress expansion coupling to minimum length. Cement one end, to one of the fixed conduits. Apply cement to second conduit. Extend expansion coupling fully onto second conduit.
 
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PoorOwner

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This is what I am trying to do, and it is indoors.

The pipe will be thru the wall and the LB will be glued on.


I could try to apply glue to the LB first and swing it over the pipe, but it won't be very strong or I will get stuck before the fitting fully seats, ruining the job because it is going at an angle.

So thinking of using that expansion, I guess a modified coupling works too, I don't have anything that would ream out a coupling.

The other thing, that expansion says it is compatible with Sch80 and 40, I am using 40 because using 80 the ID is smaller violates the fill rate (3x 4awg + ground) So not sure what the ID of the expansion fitting is.
 

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Innovate1

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Depending on the distances between the 90, LB and panel it should be easy enough to spring things enough to get the joints on both ends glued up. Maybe get a helper so you can apply glue to both ends and get it together a little faster. I don't see the need for an expansion joint or smooth coupling but maybe I am missing something... Some dimensions and more detail would help. Is the conduit into the wall already in place?
 
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PoorOwner

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The conduit into the wall will be done first, so I don't have to shoe horn this on the other side.

The panel is already in place with outgoing conduit. The LB is about 1-2 feet down and to the side.

Now I think, I will try to fit everything really well, apply glue to LB and wall pipe, then put it on LB pointing a little below horizontal and then rotate it up, so the end goes into the KO. The dry fit will let me know if it is possible or not. I will not prime the fitting so it the glue have a little more time to rotate. (I know you don't have to prime but sometimes I do)
 

BD1

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north side
I knew they existed in PVC plumbing, but never thought about it for PVC conduit. Never needed one for conduit.

A plumbing PVC coupling works perfect on PVC electrical conduit. IF you want to keep with the gray color, just file the stop out of a regular coupling and you have a slip coupling. Place on pipe ,slide down ,mark pipe where you want coupling to stop, brush glue on pipe , and slide to marked position.
 

pattenp

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A plumbing PVC coupling works perfect on PVC electrical conduit. IF you want to keep with the gray color, just file the stop out of a regular coupling and you have a slip coupling. Place on pipe ,slide down ,mark pipe where you want coupling to stop, brush glue on pipe , and slide to marked position.

Uh... yeah... that's what I said back in post #5. But I think you can get conduit repair couplings without the stop.
 

Bert_

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NW Iowa
Some people get bent out of shape or the color of a pipe or fitting. I've used plumbing couplings before for electrical. 4" plumbing couplings were much easier to find than electrical, lot cheaper too.

Use whatever works, if it won't be seen don't worry about the color. I don't mean that for 90*s or stuff like that.
 
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