Abstract: A strip assembly helically windable to form a pipe is disclosed. The strip assembly includes a pair of joined elongate strips, each strip having a strip width and a strip height and each strip including: a base; at least one longitudinal rib upstanding from the base; a pair of spaced apart longitudinal parallel edges; and an angled joining end surface. Each joining end surface has a joining width, the joining width at least 5% greater than the strip width. Also each joining end surface has a joining height, the joining height at least 10% greater than the strip height. The additional joint area provided by the angled joining end surfaces provides a significantly stronger joint.

Abstract: A method is disclosed for winding a composite strip onto a spool having a hub in which the strip includes a plurality of laterally spaced apart lengthwise extending rib portions upstanding from the base portion. The method comprises the steps of feeding the strip towards the hub of the spool; driving the fed strip through a roller set so as to plastically deform the strip to give it a curved base portion; and winding the deformed strip onto the hub to form spooled strip, the winding creating tension in the strip. The plastic deformation of the strip through the roller set substantially reduces the tension in the strip that would otherwise occur.

Abstract: A spool winding assembly for winding a composite strip onto a spool having a hub is disclosed. The strip includes an elongate plastic strip having a flat base portion and a plurality of laterally spaced apart lengthwise extending rib portions upstanding from the base portion; and a plurality of elongate reinforcing members extending lengthwise within respective rib portions, the rib portions and the reinforcing members forming composite ribs. The assembly includes: a main frame, a spool holder for rotatably supporting the spool relative to the main frame, a spool drive unit for driving the spool with respect to the main frame, a carriage mounted for lateral movement with respect to the spool, a bender mounted to the carriage for receiving the strip as it is fed towards the hub of the spool and for deforming the strip to give it a curved base portion, and a bender drive unit operably connected to the bender for driving the strip through the bender.

Abstract: A composite strip 10 windable to form a helical pipe for transporting fluid is disclosed. The composite strip comprises: an elongate plastic strip 11 having a base portion 12, the base portion 12 having an upper side defining an outer face 15; and at least one lengthwise extending composite rib portion 20 upstanding from the outer face 15 of the base portion 12. The rib portion 20 has a distal end 23 remote from the base portion 12. The composite rib portion comprises: an elongate inboard reinforcing member 30 disposed within or adjacent to the base portion 12; an elongate outboard reinforcing 40 member disposed within the distal end 20 of the rib portion 20 parallel to the inboard reinforcing member 30; and an elongate intermediate plastic web 23 portion extending between the inboard and outboard reinforcing members 30, 40. When wound into a helical pipe, the composite rib portion 20 reinforces the pipe against radial crushing loads.

Abstract: A composite strip 10 windable to form a helical pipe is disclosed. The composite strip 10 comprises: an elongate plastic strip 11 having a base portion 12 and at least one lengthwise extending rib portion 20 upstanding from the base portion 12; and an elongate reinforcing strip 30 extending lengthwise and supported laterally by the rib portion 20, the reinforcing strip 30 having a height to thickness ratio of at least three to one and orientated substantially perpendicular to the base portion 12. When wound into a helical pipe, the reinforcing strip 30 reinforces the pipe against radial crushing loads. A bead 40 seals the reinforcing strip 30 from the environment. Desirably the composite strip 10 further comprises: a planar lamina 50 extending lengthwise and bonded to the base portion 12, the lamina 50 having a higher Young's modulus and strength than those of the plastic strip 11. The lamina 50 greatly improves the pressure rating of a pipe wound from the strip 10.

Abstract: A composite strip 10 windable to form a helical pipe is disclosed. The composite strip 10 comprises: an elongate plastic strip 11 having a base portion 12 and at least one lengthwise extending rib portion 20 upstanding from the base portion 12; and an elongate reinforcing strip 30 extending lengthwise and supported laterally by the rib portion 20, the reinforcing strip 30 having a height to thickness ratio of at least three to one and orientated substantially perpendicular to the base portion 12. When wound into a helical pipe, the reinforcing strip 30 reinforces the pipe against radial crushing loads. A bead 40 seals the reinforcing strip 30 from the environment. Desirably the composite strip 10 further comprises: a planar lamina 50 extending lengthwise and bonded to the base portion 12, the lamina 50 having a higher Young's modulus and strength than those of the plastic strip 11. The lamina 50 greatly improves the pressure rating of a pipe wound from the strip 10.

Abstract: An hydraulic control arrangement (66) in association with a pipe relining machine Includes fluid pressure supply and return lines (32, 33), a motor controller (80) to control a motor (67) and a radial position controller. The radial position controller supplies fluid under pressure to a radial positioning arrangement (46) to set diameter of a relined pipe. The radial position controller has a first normally closed valve (83) supplying fluid under pressure to the radial positioning arrangement (46) and a second normally open valve (84) allowing fluid to be withdrawn from the radial positioning arrangement (46). The arrangement (66) allows the pipe relining machine to be withdrawn in the event of a failure.

Abstract: A machine (200) for winding a strip of material (212) into a helical pipe wherein adjacent convolutions of the strip (212) are interlocked. The machine comprises: a frame (220) having circumferentially spaced supports in the form of rollers (266, 276, 278, 286, 288, 296 and 298) adapted to bear against the inner periphery of the pipe being wound, the outer peripheral surfaces of the rollers forming a helical path for the strip (212) and along which the strip (212) is directed when the machine (200) is in use; driving rollers (224) mounted to the frame (220) for driving the strip (212) around the outside of the rollers so as to follow the helical path and cause the adjacent edges the strip (212) to interlock; and drive means (226) mounted to the frame for driving the driving rollers (224). The driving rollers (224) and the drive means are located wholly inside of the path formed by the rollers and no part of the machine (200) engages the outer periphery of the pipe being wound.

Abstract: A plastic profiled strip (10) is provided for producing helically wound tubes or pipes, the strip (10) having female and male joint formations (13, 14) extending along opposite longitudinal margins thereof and arranged so that upon spirally winding the strip into a tubular form, the joint formations (13, 14) can be interlocked to thereby lock adjacent windings of the strip together, the male joint formation (14) comprising a hinged flap (15) which is flexibly connected to the strip (10) for hinging movement between a disengaged or unlocked position displaced from the plane of the strip (10) and a locking position wherein it interlocks with the female joint formation (13) of an adjacent winding of the strip (10).

Abstract: This invention relates to improvements to reinforced ribbed structures, and in particular to reinforced or strengthened spirally wound pipes or tubes made from composite materials.

Abstract: The invention relates to apparatus for helically winding pipes from tube forming plastics strip comprising a single fixed rigid loop formed from a length of metal band, wherein the inner surface of the loop forms a spiral path along which the strip is directed when helically wound, strip guide means for guiding the strip into the path of the loop, and driven roller means for driving the strip around the spiral path and for joining together adjacent edges of adjacent convolutions of the strip, whereby during the helical winding process, the strip is driven around the spiral path in frictional engagement with the loop inner surface, maintaining intimate contact therewith, to thereby form the pipe.

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.

Abstract: A method and means of slip control for helically wound pipes wherein the pipe is formed by helically winding a strip of plastics material and the edges of the convolutions of the strip are interconnected, wherein a slip-control member applied to the interconnected edges of the convolutions of the strip is arranged to be withdrawable progressively from the pipe to allow slip linearly between the interconnected edges of the convolutions of the pipe when torque is applied to the pipe.

Abstract: A method for protecting conduits in which a tube produced by helically winding a strip and interconnecting the edges of the strip to allow longitudinal slip is placed adjacent the area to be lined or overlapped. The tube is held at a selected diameter during placement and a winding force is applied by expander means driven along the tube to cause the interconnected edges to slip progressively change the diameter of the tube to engage the conduit. The progressive change may be caused by continuing the step of winding.

Abstract: The method of reinforcing a structure formed by interengaging the edges of ribbed strip (1) formed of a plastics material to form a helically wound tube, the strip (1) comprising a plurality of the ribs (2) spaced apart and upstanding from a base (24), characterized by engaging on the strip (1) a non-planar reinforcing member (10), and locking the reinforcing member (10) to the strip to form an attached strength member to attain lateral stability of the ribs.