CIPP Rehabilitation

Proven CIPP lining processes and technologies ensure reliable rehabilitation

National Underground Group’s CIPP rehabilitation team employs proven processes on each project. Before CIPP installation, the host pipe is cleaned and all debris, roots and corrosion byproducts are removed. The flexible CIPP liner is then vacuum impregnated with a thermosetting resin system to ensure a uniform wetout. The CIPP liner is next inverted through the existing manhole or access point and processed by a hydrostatic water column and cured by circulation of hot water, or by means of air pressure and cured by controlled steam.

A new pipe is formed as the CIPP liner cures and hardens within the host pipe. Inspection and testing are performed to make sure the “new” pipe performs as designed, assuming all functions of the host pipe. The pipe-in-pipe solution is solely sustainable. Further, the “new” pipe bears all external loads without the support of the host sewer pipe, providing a complete, structural solution.

Quality materials deliver sustainable service

Our Services – Fiberglass Reinforced Pipe

National Underground Group also offers glass reinforced pipe (GRP) relining. This method entails completely relining sanitary sewer and storm drain pipe / culverts using a thermosetting, resin-impregnated flexible tube that is inverted and cured with hot water or steam.

During research and development, National Underground Group worked closely with Applied Felts to deliver fiberglass strength with traditional felt liner installation methods. This exclusive technology fully integrates and blends the unique properties of each, providing the strongest, most robust liner on the market today with some key advantages:

• Superior physical and mechanical properties
• Matrix reducing liner, particularly in large diameter liners
• Lighter weight makes transportation, handling and installation faster and easier