Rehabilitating underground pipes with expanding helically wound liner

• US 5,101,863 A
• Filed: 12/18/1990
• Issued: 04/07/1992
• Est. Priority Date: 05/02/1988
• Status: Expired due to Term

• Current Assignee: RIB Loc Australia Pty., Limited
• Original Assignee: RIB Loc Australia Pty., Limited
• Inventors: Fujii, Shigeki, Sonku, Masahisa, Hirayama, Hirozo, Yasuhara, Minoru
• Primary Examiner(s): Bryant, III, James E.
• Application Number:
  US07/603,771
• Time in Patent Office: 476 Days
• Field of Search: 138/97, 138/98, 138/154, 138/121, 138/122, 405/150, 405/154, 264/268, 264/269, 264/36
• US Class Current: 138/98
• CPC Class Codes: B29C 53/78 using profiled sheets or strips
• CPC Class Codes: B29C 63/32 by winding helically
• CPC Class Codes: F16L 55/1645 a sealing material being introduced inside the pipe by means of a tool moving in the pipe
• CPC Class Codes: F16L 55/1655 a pipe being formed inside the old pipe by winding strip-material

Abstract

A method of rehabilitating underground pipes which comprises the steps of: (a) forming a liner pipe (5) by winding a strip (4) made of a synthetic resin into a helical shape so that the side edges of the convolutions of the wound strip (4) are interengaged with each other; (b) continuously introducing the liner pipe (5) into an underground pipe (1) while the liner pipe (5) is being advanced inside the underground pipe (1); inserting a slip restraining member in the form of a wire rod (6) continuously to the interconnected edges of the convolutions of the said strip (4), and then removing the said strip (4) when the diameter of said liner pipe (5) is to be increased at the same rate as said strip (4) for forming said helical liner pipe (5) is conveyed.

Claims

1. A method of rehabilitating underground pipes (1) using a lining consisting of a helically formed liner pipe (5) made of a synthetic resin, which comprises the steps of:

(a) forming a liner piper (5) by winding a strip (4) made of a synthetic resin into a helical shape around a virtual cylinder, so that the side edges of the convolutions of the wound strip (4) are interengaged with each other;

inserting a slip restraining member in the form of a wire rod (6) continuously to the interconnected edges of the convolutions of the said strip (4), and then removing the said strip (4) when the diameter of said liner pipe (5) is to be increased at the same rate as said strip

     94) for forming said helical liner pipe (5) is conveyed;

(b) continuously introducing said liner pipe (5) into an underground pipe (1) while said liner pipe (5) is being advanced inside the underground pipe (1);

(c) fixing the leading end of said liner pipe (5) to the underground pipe when a required length has been advanced;

(d) further advancing said liner pipe (5) inside the underground pipe (1) with its leading end fixed to the underground pie (1), so that the wound strip (4) is allowed to slide around the virtual cylinder with its side edges still being interengaged with each other, resulting in the gradual increase in the diameter of said helical liner pipe; and

(e) injecting a backfilling material into the space between the outer surface of said liner pipe (5) and the inner surface of the said underground pipe (1) by moving a nozzle (22) for supplying the backfilling material in the direction of the axis of said liner pie (5) synchronously as said rod is withdrawn and the increasing diameter is shifted in the same direction.

2. The method of rehabilitating underground pipes (1) with a liner pipe (5) formed from a strip (4) of synthetic seam according to claim 1 wherein the backfilling material is a foaming material.