Pipe joint sealer

A method for sealing pipe joints comprising the steps of:

• (a) wrapping the pipe joint with a resilient substrate material impregnated with a urethane prepolymer so as to be reactive to moisture such that the substrate material expands when exposed to moisture and contracts toward substantially its original volume when dry, wherein said resilient substrate is substantially surrounded by a geotextile fabric covering adapted to allow moisture to pass from the environment to the impregnated substrate while preventing the passage of foreign material and fines to the impregnated substrate;
• and
• (b) applying a clamping device about said pipe joint such that the substrate material disposed within the geotextile covering is captured intermediate the clamping device and the pipe joint.

A method of sealing a spigot and bell pipe joint comprising the steps of:

• (a) disposing a substrate material impregnated with a urethane prepolymer and enclosed within a geotextile fabric cover between the spigot and the bell of the pipe joint;
• and
• (b) compressing said substrate material disposed within the geotextile fabric between said spigot and said bell to maintain said substrate material in a position so as to be contacted by moisture extending about said bell and said spigot, expanding said substrate material by moisture absorption to form an expanded sealing at the pipe joint, and contracting said substrate material toward substantially its original volume upon removal of the moisture to a dry state for again expanding said substrate material upon reoccurring contact with moisture.