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Reconstruction & Repair for canal and culvert

CPR method

Chunichi Copro (C) Pipe (P) Renewal (R) method

This is our unique technology is for renovating vertical pipe such as drainage pipe for high-rise building and condominium.
It is no impact on residents and buildings with a short time and low cost, because it is a simple construction that does not need large equipments.

CPR method
  • No impact on residents
    The maintenance and repair of deteriorated miscellaneous drainage pipe in condominium have been carried out a lot in recent years. It involves a lot of incidental construction such as wall demolition and repair of pipe spaces, which would be a lot of burden for the resident's lives. This method is designed to reduce amount of work and extend the life of the pipe.
  • Cost reduction
    There is no need for large-scale renovation and equipment, and it can be completed in a short time with safe, easy and reliable.
  • It can be installed according to the site environment even in a narrow space.
Scope of the CPR method
  • Types and nominal diameters of existing pipes
    Type of piping: steel pipe, cast iron pipe, PVC pipe, lead pipe, fume pipe
    Nominal diameter : 80A to 200A
  • Standard application conditions
    a. The degree of breakage, bending, or deformation of the rehabilitated pipe shall be such that the rehabilitated material can be smoothly inverted and retracted for insertion.
    b. Protrusions or other obstructions, if any, inside existing piping shall be removed in advance.
Overview of materials
The structure of the material is shown below. Overview of materials


Cut off the insertion and termination for inversion insertion.
Removes stagnant materials after checking the inside of existing pipe with TV camera.

Mix the resin and hardener that will be new pipe, and impregnate it in the pipe cut to the construction dimensions.
The impregnated pipe is inserted with pressure and inverted into the existing pipe.
When the tube reaches the end, insertion is complete.

The resin is cured by the prescribed pressure, temperature and time to form a pipe. Then bring it down to proper temperature.

The mouth and end of new pipe connect with existing pipe.

Perforate carefully for the branch pipe and connect with our special joint.
Investigate and confirm by TV camera.

By Insituform method catalog issued from Japan Insituform Association