Abstract: A method of lining a channel can be provided which includes the steps of: installing at a work site a roll having wound thereon a rigid or semirigid plastic pipe shaped initially in the form of an approximately round tube and deformed from the initial form to a flat tubular form, paying off the pipe as softened by heating from the roll installed at the work site toward an inlet of the channel to be lined, and folding the paid-off flat pipe in two to a U shape at a position between the roll and the channel inlet. The U-shaped pipe is hardened by forced cooling from outside immediately after the folding step while being restricted in shape, then inserted into the channel while being thus hardened and thereafter restored to the initial form by being inflated with heat and pressure applied from inside, whereby a lining of improved quality can be formed with an improved work efficiency.

Abstract: In renovating an existing underground pipe with a new metal pipe installed inside the underground pipe, the invention provides a method of repairing the existing underground pipe characterized by transporting a metal tubular material as wound up in the form of a roll to a repair site, the tubular material being deformed to a flat folded form so as to be diminished in effective outside diameter and to be restorable to a metal pipe of an outside diameter corresponding to the inside diameter of the underground pipe when inflated by application of pressure from inside, installing the roll of tubular material on the ground, subsequently inserting the tubular material into the underground pipe through an underground work pit while unwinding the tubular material from the roll, closing opposite ends of the inserted portion of the tubular material, and thereafter restoring the closed portion of the tubular material to a metal pipe of circular cross section by applying pressure thereto from inside with a pressure fluid

Abstract: An apparatus easily movable inside pipes for cutting off projections in the interior of the pipe along the inner surface of the pipe. The apparatus includes a carrier movable inside the pipe. The carrier is provided with a shaft reciprocatingly movable axially of the pipe and rockingly rotatable circumferentially of the pipe, a rocking block movable with the shaft and a drive device for the shaft. The rocking block has a cutter blade reciprocatingly movable axially and radially of the pipe as projected forward from the block axially of the pipe, and drive devices for the blade.

Abstract: A method of forming a rigid or semirigid plastics tube lining over the inner surface of a branch pipe portion as joined at its one end to an underground main pipe through the other end thereof substantially open to the surface of the ground as a work opening, the method being characterized by inserting a rigid or semirigid plastics tube into the branch pipe portion from the work opening with the forward end of the tube substantially closed, and subsequently supplying a fluid into the tube to inflate the tube radially of the branch pipe by applying heat and pressure to the tube with the fluid from inside directly or indirectly and thereby line the branch pipe portion with the rigid plastics tube. The pipe portion can be lined from the ground surface efficiently without necessitating labor for excavation of the ground, cutting off the branch pipe portion and restoring the piping to the original state.

Abstract: In inserting a rigid plastic tube through a pipe while paying out the tube from a drum having the tube wound thereon in a flat form, a heating fluid is supplied into the plastic tube to pass the fluid from its one end toward the other end thereof and thereby heat and soften the plastic tube over the entire inner peripheral surface of the tube. The plastic tube as wound on the drum can be heated and softened uniformly at every portion over the entire length thereof and can further be held so softened also during the insertion of the tube through the pipe. The tube can be easily passed through an intermediate bent pipe portion, if any, and efficiently inserted through the pipe.

Abstract: A small diameter shield tunnel is constructed by using a shield machine and assembling within a tail portion of the machine a set of three 120.degree. arcuate segments into a segment ring. An annular seal device is axially movably provided between the outer periphery of the segment ring and the inner periphery of a tail skin plate defining the tail portion of the machine. A back-filling material is charged into an annular gap formed between the outer peripheral surface of the segment ring and natural soil surrounding the segment ring. The back-filling material within the annular gap is compressed by the seal device which is caused to move between the inner peripheral surface of the tail skin plate and the outer peripheral surface of the segment ring, in the axial direction of the tunnel, away from a face where excavation of natural soil is carried out mechanically.

Abstract: The present invention is for a method of lining a pipe with a rigid to semirigid plastic tube which is inserted through the pipe by inflating the tube by application of heat and pressure. The method is characterized in that the tube has a large wall thickness and is formed with a multiplicity of bores extending through the tube wall axially thereof and arranged in parallel at a spacing circumferentially of the tube. The tube is heated by passing a heating fluid through the bores. The tube having the large wall thickness can be uniformly heated throughout the entire wall thickness so as to be inflated fully by the application of pressure, free of the likelihood of insufficient inflation or rupture and to line the pipe.

Abstract: A method of forming a rigid or semirigid plastics tube lining over the inner surface of a branch pipe portion as joined at its one end to an underground main pipe through the other end thereof substantially open to the surface of the ground as a work opening, the method being characterized by inserting a rigid or semirigid plastics tube into the branch pipe portion from the work opening with the forward end of the tube substantially closed, and subsequently supplying a fluid into the tube to inflate the tube radially of the branch pipe by applying heat and pressure to the tube with the fluid from inside directly or indirectly and thereby line the branch pipe portion with the rigid plastics tube. The pipe portion can be lined from the ground surface efficiently without necessitating labor for excavation of the ground, cutting off the branch pipe portion and restoring the piping to the original state.