Keyhole Patch-Pads and Tools by Trenton

Enables utilities to apply a coating to a pipe surface through a small-diameter hole or keyhole.


The Trenton Keyhole Patch-Pad and Tools enable utilities to apply a coating to a pipe surface through a small-diameter hole or keyhole. The components include two tools (attached to extendable poles) and a Patch-Pad with pre-applied coating.

End Use

The system is an excellent solution for applying a coating through a small-diameter hole over cadwelds or coating holidays. Please see our Trenton Patchpad Application Video (9.6 MB).


  • Tool or hand-applied
  • Non-hazardous, no VOCs
  • No waiting for drying or curing
  • Immediate backfill
  • Minimal surface preparation


Patch-Pad: 4” X 4", 6' X 6'" and 5"×10" PAD
Tools: Patch-Pad applicator and a finishing tool

Specifications, Patch-Pad Coating

Color: White
Flash point: 350°F (minimum)
Dielectric strength: 100 volts per mil

Note: This product is protected and covered by one or more of the following United States Patents and their foreign equivalents: U.S. Patent Nos. 5,540,985 and 7,273,073.

Operating Procedures

  1. Wire brush and clean the surface of any loose coating, rust, scale and foreign matter.

  2. Secure the extension handles (supplied by Trenton or by the utility) to the Patch-Pad applicator and the finishing tool.

  3. Attach a pre-coated Patch-Pad to the applicator tool, (or anticorrosion compound can be applied by hand directly to the bottom of a dry pad).

  4. The applicator tool, with the coated Patch-Pad attached, is then lowered into the keyhole and onto the pipe surface to be protected.

  5. Use the finishing tool to hold the Patch-Pad to the pipe while lifting off the applicator tool and leaving the Patch-Pad on the pipe.

  6. Use the finishing tool to press the pad firmly to the pipe, making sure that coating compound is squeezed out on all edges and ensuring that the pad is firmly adhered.

  7. The Patch-Pad (with coating) now protects the pipe, and backfill can begin immediately