Abstract: A method for inverting a tubular liner in a hollow conduit involves: forming a cuff from the tubular liner, the cuff having an opening through which the liner is fed; and while feeding the liner through the cuff opening, feeding a gas under pressure through a gas inlet port formed in the liner to a space between the cuff and the remainder of the liner, thereby causing inversion and inflation of the liner into and through the conduit. After a portion of the liner has been inverted in the conduit, a region of the cuff and liner upstream of the gas inlet port is sealed off, thereby causing inversion of the remainder of the liner in the conduit. Optionally, before a trailing end of the liner is fed through the opening of the cuff, the trailing end is sealed to prevent flow of gas therefrom.

Abstract: A method for inverting a tubular liner in a hollow conduit involves: forming a cuff from the tubular liner, the cuff having an opening through which the liner is fed; and while feeding the liner through the cuff opening, feeding a gas under pressure through a gas inlet port formed in the liner to a space between the cuff and the remainder of the liner, thereby causing inversion and inflation of the liner into and through the conduit. After a portion of the liner has been inverted in the conduit, a region of the cuff and liner upstream of the gas inlet port is sealed off, thereby causing inversion of the remainder of the liner in the conduit. Optionally, before a trailing end of the liner is fed through the opening of the cuff, the trailing end is sealed to prevent flow of gas therefrom.

Abstract: A method for inverting a tubular liner in a hollow conduit involves: forming a cuff from the tubular liner, the cuff having an opening through which the liner is fed; and while feeding the liner through the cuff opening, feeding a gas under pressure through a gas inlet port formed in the liner to a space between the cuff and the remainder of the liner, thereby causing inversion and inflation of the liner into and through the conduit. After a portion of the liner has been inverted in the conduit, a region of the cuff and liner upstream of the gas inlet port is sealed off, thereby causing inversion of the remainder of the liner in the conduit. Optionally, before a trailing end of the liner is fed through the opening of the cuff, the trailing end is sealed to prevent flow of gas therefrom.

Abstract: The invention provides a tailored assembly of a flexible resin absorbent material (22, 24, 26). It is in the form of a "T" and is of tubular cross section. The arms of the T are intended to lie on the surface of a main underground pipe which the leg of the T extends into a lateral pipe which connects with the main pipe. The whole assembly is soaked in curable synthetic resin and it is placed in position and held there whilst resin cures by means of an inflatable bag (28) which is located inside the assembly and is also tailored to T configuration.