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AssigneeAshimori Kogyo Kabushiki Kaisha
InventorsHiroyuki Sakuragi, Masahiro Seshimo, Futoshi Makimoto, Shinichi Takebe, Takuji Sokawa, Hitoshi Saito
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The present invention provides a repairing tube to be used in pipe lines such as gas conduits, water supply lines and sewer lines, chiefly those buried in the ground, for the purpose of repairing the pipe lines. More particularly, the present invention relates to a repairing tube including a rigid pipe formed of thermoplastic resin and a tubular woven fabric and a method for repairing or reinforcing a pipe line with the repairing tube. Furthermore, the present invention relates to a method for removing the repairing tube in its collapsed form out of the pipe line, for example when the repairing tube installed in the pipe line has become superannuated or it has been collapsed for some reason or other to impair the function of the pipe line and hence it is desired to reline the pipe line.
A repairing tube used in a pipeline repairing process in which the tube is deformed under heating, pulled into a pipeline and expanded into a cylindrical configuration using a heated and pressurized fluid so that the tube conforms to the internal wall surface contours of the pipeline, characterized in that the tube comprises a rigid pipe including a thermoplastic resin having a Vicat softening point higher than the temperature of the heating and a tubular woven fabric, the tubular woven fabric being integrated with the rigid pipe either by being brought into intimate contact with an interior wall surface or an exterior wall surface of the rigid pipe or by being embedded in the thermoplastic resin of the rigid pipe, the strength of the tube per unit width in the longitudinal direction in kgf/cm, when heated, being not less than 1.3 times DP, DP being defined as the product of the diameter D of the pipeline and the pressure P of the fluid.
A method for repairing a pipe line with a repairing tube comprising a rigid pipe formed by extrusion molding of thermoplastic resin into a cylindrical shape and a tubular woven fabric, the method comprising the steps of:
A method for removing a repairing tube, which has been heated and expanded by a fluid in order to line a pipe line, out of the pipe line lined therewith, the strength of the tube per unit width in the longitudinal direction in kgf/cm, when heated, being not less than 1.3 times DP, DP being defined as the product of the diameter D of the pipeline and the pressure P of the fluid, which comprises the steps of evacuating the interior of the repairing tube to deform the repairing tube into a reduced cross section and pulling the repairing tube out of the pipe line.
A method for removing a repairing tube, which has been heated and expanded by a fluid in order to line a pipe line, out of the pipe line lined therewith, the strength of the tube per unit width in the longitudinal direction in kgf/cm, when heated, being not less than 1.3 times DP, DP being defined as the product of the diameter D of the pipeline and the pressure P of the fluid, which comprises the steps of heating the repairing tube into a softened state, evacuating the interior of the repairing tube to deform the repairing tube into a reduced cross section and pulling the repairing tube out of the pipe line.
Dependencies are inferred from the claim text.