# Internal Pipe Plug



## plbgbiz (Aug 27, 2010)

I need to plug a 3" CI pipe under a slab from outside the house. The only access I have is through the downstream backwater valve about 15' away. This needs to be a permanent plug so a test ball probably won't suffice.

Any ideas?


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## GREENPLUM (Jul 27, 2008)

how bout


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## plbgbiz (Aug 27, 2010)

How do I get the concrete 15' upstream through the BW valve?


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## plbgbiz (Aug 27, 2010)

This is to avoid going through the slab. The line runs parallel and patially inside of a HUGE footing on a monolithic slab.


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## SlickRick (Sep 3, 2009)

Houston, we have a problem.


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## plbgbiz (Aug 27, 2010)

slickrick said:


> Houston, we have a problem.


Exactly...:help:


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## SlickRick (Sep 3, 2009)

Expanding sealer of some kind with a hose? What kind of budget? I think the equip, from the gulf is available.


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## PLUMBER_BILL (Oct 23, 2009)

plbgbiz said:


> I need to plug a 3" CI pipe under a slab from outside the house. The only access I have is through the downstream backwater valve about 15' away. This needs to be a permanent plug so a test ball probably won't suffice.
> 
> Any ideas?


I have no idea. Unless from the backwater valve, could you not insert a pipe into the 3" cast iron. Driving it far enough that it shows up on the other side of the house. Dig down get the pipe then pull a cable through. Then BURST the 3" pulling through HDPE capped ???


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## PLUMBER_BILL (Oct 23, 2009)

plbgbiz said:


> How do I get the concrete 15' upstream through the BW valve?


John look here http://parrsplumbing.blogspot.com/2008/11/more-tools-continued.html I used this to groute fiberglass tubs and showers.
.
Perhaps you could alter the discharge lenght. I moved moter with only 2-3
lbs or compressed air.

Worth a try I guess!


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## plbgbiz (Aug 27, 2010)

Bill,

I'm not sure I'm getting the full idea. You have compressed air at the bottom of the chamber and this forces the grout through the tube? 

What keeps the air from bypassing the mud mixture?


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## plbgbiz (Aug 27, 2010)

Indie & I were just talking about attaching a tube a camera head and sending spray foam up stream. Not sure if I could aim it properly.


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## rocksteady (Oct 8, 2008)

What's above this section of pipe you need to cap? What kind of flooring? It might actually be cheaper and faster to locate it and go through the slab. If all you need to do is cap the line, you won't need a big hole. If you can locate it, you can probably get away with a 8" to 10" square hole.








Paul


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## plbgbiz (Aug 27, 2010)

The line is running parallel and inside a 30" x 30" footing. That's why i can't do the pipe burst.


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## SlickRick (Sep 3, 2009)

plbgbiz said:


> Indie & I were just talking about attaching a tube a camera head and sending spray foam up stream. Not sure if I could aim it properly.


That is along the lines I was thinking. If have access to both ends you should be able to pull a string through the line and possibly tie it to a polly hose. Put your camera in the line and pull the polly line into position, back your camera way back, apply the foam, push the camera back in to check the results.


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## rocksteady (Oct 8, 2008)

How is spray foam a more permanent and leak proof fix than a test ball? What if you were to somehow modify a test ball to be filled with foam? 



Paul


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## SlickRick (Sep 3, 2009)

rocksteady said:


> How is spray foam a more permanent and leak proof fix than a test ball? What if you were to somehow modify a test ball to be filled with foam?
> 
> 
> 
> Paul


The test ball will most likely leak down at some point. And how would you detach the hose?


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## GREENPLUM (Jul 27, 2008)

why cant you cut off the backwater valve and cap it there? 

i dont understand why you would need to cap off a pipe under the slab. splain peeze


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## rocksteady (Oct 8, 2008)

GREENPLUM said:


> why cant you cut off the backwater valve and cap it there?
> 
> i dont understand why you would need to cap off a pipe under the slab. splain peeze


 
Are there fixtures between the backwater valve and this area 30' away that need to stay in service?





Paul


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## rocksteady (Oct 8, 2008)

How large can this plug be? How about this?

Run a camera down the line to where you want the plug to start and mark the push-rod. Pull it out and transfer that measurement to a stiff sewer cable (5/8" or 3/4" maybe). Remove the cutter head on the cable and replace it with a circular board made of plastic/metal/wood/whatever, as long as it's stiff. Drill a hole off center and attach a hose thread connector in the plate. Now attach a hose to the plate and zip tie the hose to the cable along the full run. Push the cable/plate/hose contraption into the line up to the mark and pump slurry into the line from the hose. If you were able to get a good seal on the inside of the pipe with rubber or foam, you could probably keep most of it from coming back.


It's getting dangerous now because I've started to really pull some stuff out of my ass. If this doesn't sound like it'll work, I'm sure my next idea will at least be entertaining. Don't ask what it is, I haven't had the vision yet. 







Paul


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## rocksteady (Oct 8, 2008)

You could probably use something like a Nerf ball instead of or in addition to the plate to seal up on the pipe. Kind of like those balls they use to clean concrete pump lines.





Paul


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## SlickRick (Sep 3, 2009)

Fill a flush-able sonde with foam, attach a small amount of C4, use your locator to monitor the sonde, as it passes the desired location detonate the charge, problem solved.


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## Richard Hilliard (Apr 10, 2010)

I take it this drain went to some type of fixture that was removed. Could there be a vent line capped in the wall to make it easier to reach and pour conrete?


Check with a concrete place to send thier hose upstream to concrete.


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## rocksteady (Oct 8, 2008)

Now we're talking. :thumbup:



How about some sort of tampon bomb? Those to a pretty good job of stopping up mainlines.









Paul


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## plbgbiz (Aug 27, 2010)

Hall bath upstream has been rerouted outside. The master bath is staying on the original line to the BW valve. The upstream vents are on the new line. upstream from the master there is broken pipe so there will always be dirt/groundwater/root intrusion. there is good pipe just before the master bath tie in but it is inaccessible through the concrete.

So being able to remotely deploy a plug/foam/ball-o-muck/etc. seems like a good idea. It does need to be permanent. Only get one shot. If it fails...well...let's just say it better not fail.


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## plbgbiz (Aug 27, 2010)

Going to jet the line clean first. How 'bout this...

1. jet the line
2. attach tubing for foam to the inside of a 2-1/2" poly cap.
3. push poly cap upstream with duct rodder
4. follow with camera
5. apply a/b through tube to backside of poly cap till visibly squirting out around all sides

6. How do I get the tube out? Maybe the tube is inserted with a washer on the backside so it can push in the cap but when pulled it comes out.
7. Will the foam be an effective permanent plug?


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## SlickRick (Sep 3, 2009)

plbgbiz said:


> Going to jet the line clean first. How 'bout this...
> 
> 1. jet the line
> 2. attach tubing for foam to the inside of a 2-1/2" poly cap.
> ...


Do a test run on a piece of CI. Don't fill it up all the way. Then stand it up on end and fill it with water. If it holds water, I would say it was good. Then break the CI and inspect your plug for a uniform seal.


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## PLUMBER_BILL (Oct 23, 2009)

plbgbiz said:


> Bill,
> 
> I'm not sure I'm getting the full idea. You have compressed air at the bottom of the chamber and this forces the grout through the tube?
> 
> What keeps the air from bypassing the mud mixture?


 
THE BLACK TUBE HAS TO STAY VERTICLE, I would fill the tube to about 4" from the top, I would take a air supply regulated down to 2-3 pounds and let it hooked up. As morter was forced through the tube more volume of air was applied until all morter was expended then you'd get a woosh. 
You have to get the mix right not too stiff but when the valve was opened it did not run out either, it needed the air to move it.


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## Ron (Jun 12, 2008)

Contact BP they will plug the line for you, they know what there doing, might take a few months but what the hey. :laughing: JK Only meant for a laugh Back On Topic.


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## Redwood (Sep 8, 2008)

Hey John,

We have done quite a few jobs around here where lines to the city sewer were being abandoned.

The cities we have done this in allow us to shoot a liner coming within 2' of the city line. The liner is clamped shut on the end, dead ending the line and keeping ground water and soil from washing into the city sewer. That saves some big bux not having to dig the busy street. Of course you'l have to reestablish the other line.


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