US Patent 9163770 Method and apparatus for lining a pipe

The method for rehabilitating a damaged section of a pipe without a need for a resin absorbent liner is provided. The method includes pumping a low viscosity material towards a damaged section of pipe and changing the viscosity prior to dispensing of the material. For example, the material may be partially cured prior to dispensing. The partially cured or higher viscosity material is compressed between an inflating bladder and interior wall of the pipe, and the material that is allowed to fully cure. The bladder either can then be removed from the pipe or could be allowed to maintain in the pipe providing a new interior surface for the repaired pipe.