Patching a Hole in the Tube

“I lost a liner yesterday because there was a hole in the tube that wouldn’t allow us to hold air. We’re new to this process and I’m wondering if this is a regular occurrence and what to do if it ever happens again?”

While it is pretty rare that you’d have a hole in the liner tube that wouldn’t allow you to invert it, there are ways to save the liner and get it in the ground. The first thing is to keep yourself from panicking. Yes, you have a limited time to get the liner in the ground and under pressure to insure it cures correctly, but remaining calm will help.

The first thing to consider is where you are in time and the configuration of the liner. If you are managing your temperatures of resin and tube, you may have a lot of time to figure out what to do next. Once the tube won’t hold air, adding more air and pressure with no results tells you to stop wasting time and move forward.

If the end of the liner hasn’t passed through the gun, you can pull the tube back to find the hole. Once you determine where the hole is located you have some options. We distribute a product called Tear-Aid, which is a tape product that you can apply over the hole in the liner. In the absence of Tear-Aid you could use duct tape, but after it’s cured you will need to remove it from the surface or explain to your customer what the tape is there for.

If the hole is too large for applying tape to patch the hole, your second option is to thread the wetted-out liner through the inside of the calibration tube and shoot both together. The air and pressure will be on the calibration tube while the inversion is going forward. This method is accomplished by:

  1. Controlling the resin temperature
  2. Threading your camera through the inside of the calibration tube to attach the liner for pulling it through the cal-tube
  3. Preparing the end after inserting the liner
  4. Adding spacers to the Quik Shot™ to allow for the thicker tube and cal-tube combination
  5. Then shooting the liner & calibration tube together.

If the end of the liner has passed the gun and is now located inside the host pipe, there are a couple of alternatives to try. Using a push rod, cable machine, or your camera – you can push the assembly down the inside of the liner tube to see if you can push the nose down the line till it reaches full inversion. You can also connect the calibration tube and attempt to push the liner the rest of the way to the end with the pressure of the calibration tube inverting.

For more information call us at 888-354-6464. You can also email us at  

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