Method for manufacturing pipe-lining material

Abstract

A method is proposed for manufacturing a pipe-lining material comprising a tubular resin absorbent material covered with a tube comprised of an airtight plastic film. The tubular resin absorbent material is inserted into the tube, expanded in a columnar shape, and brought into close contact with the internal peripheral surface of the tube. A heater is wound in close contact with the external peripheral surface of the tube thus expanded. The tube and the tubular resin absorbent material are heated by energizing the heater, and the tube is thereby heat-fused to the tubular resin absorbent material. With such a method, a mechanism for moving the tube and the tubular resin absorbent material is not required. In addition, since heat non-uniformities are not generated, the tube can be uniformly heat-fused to the tubular resin absorbent material, thereby enabling a high-quality pipe-lining material to be manufactured.

1 . A method for manufacturing a pipe-lining material comprising a tubular resin absorbent material covered with a tube comprised of an airtight plastic film, wherein the tube is heat-fused to an external peripheral surface of the tubular resin absorbent material, the method comprising:
 inserting the tubular resin absorbent material into the tube, and expanding the tubular resin absorbent material and the tube in a columnar shape so as to bring the tubular resin absorbent material into close contact with the internal peripheral surface of the tube;   winding a heater in close contact with the external peripheral surface of the tube thus expanded; and   heating the tube and the tubular resin absorbent material by energizing the heater to heat-fuse the tube to the external peripheral surface of the tubular resin absorbent material.   
     
     
         2 . The method for manufacturing a pipe-lining material according to  claim 1 , wherein the heater includes heating wires that are arranged in a periodic serpentine fashion at an equal pitch inside a rectangular or square insulating cloth having a side substantially equal to an outer circumference of the tube. 
     
     
         3 . The method for manufacturing a pipe-lining material according to  claim 2 , wherein the smallest integer Z that satisfies the expression Y*Z>X is calculated for the case in which X is greater than Y, wherein X is the length of the pipe-lining material, and Y is the length over which one side of the heater extends in the length direction of the pipe-lining material;
 the calculated number Z of heaters is arranged adjacent to each other and wound around the external peripheral surface of the tube; and   the Z number of heaters is connected in parallel and energized.   
     
     
         4 . The method for manufacturing a pipe-lining material according to  claim 3 , wherein a thermoconductive sheet is wound around a tube, and the heater is wound via the thermoconductive sheet.