A pipe having an axially extending bore is defined by a pipe wall including a corrugated outer wall having axially adjacent annular outwardly-extending crests separated by valleys. The pipe wall also includes a non-linear outer layer having adjacent concave portions and convex portions. The concave portions are aligned with the corrugation crests of the outer wall so that the convex portion of the outer layer extends outwardly between at least two corrugation crests to provide improved resistanc...

The present invention is directed to a new and improved flexible hose assembly for transmitting pressurized air, gases and/or fluids between two spaced apart components. The hose assembly includes an inner liner surrounded by a helix formed of thermoplastic material having a substantially flat surface portion for bonding with the inner liner, eliminating the need for a outer cord to prevent the helix from floating relative to the liner. A self-adjusting retainer ring serves to compress the flexi...

A pressure-resistant helical corrugated pipe comprises a helical corrugated pipe wall; and two kinds of thin metal belt plates provided as a pipe wall-constituting element. The metal belt plates are disposed at least partially in overlapping relation in the direction of the thickness of the pipe wall. The overlapped portions of the metal belt plates are spaced from and held out of contact with each other by an intermediate resin layer, and the overlapped portions are integrally connected togethe...

A pressure-resistant helical corrugated pipe comprises a helical corrugated pipe wall formed by a top portion, opposite side wall portions and a bottom portion; a wide metal belt plate of a thin metal plate disposed at least at the top portion and the opposite side wall portions; and a small width metal belt plate being separate from the wide metal belt plate and disposed at the top portion of the pipe wall in overlapping relation to the wide metal belt plate in the direction of the thickness of...

A flexible hose construction and method of making the same are provided, the flexible hose construction comprising an inner corrugated hose made of polymeric material and having a plurality of outwardly convex projections with recesses therebetween and extending from one end thereof to the other end thereof, an outer sleeve of reinforcing material disposed in telescoping relation on the inner hose, and a tube of polymeric material disposed between the sleeve of reinforcing material and the inner...

A flexible strip of elastomeric material, or a fabric strip which is coated with or contains an elastomeric material is wound helically with overlapped edges. A form-giving member of stiff bendable thermoplastic material in rod-like form is laid between the overlapped edges and secured there by self adhesion of the overlapped edges. Then the tubing is heat-treated to heat-set the form-giving helix in its helical form and at the same time cure the strip and to weld the overlapped edges of the str...

A synthetic resin pipe for underground installation includes a synthetic resin strip which is spirally wound and joined to form an elongated pipe. The outer surface of this elongated pipe is smooth and continuous. Reinforcing ribs of the strip have hollow centers and protrude radially inwardly. Strip lateral extents which are adjacent to the reinforcing ribs are joined to form the smooth outer surface of the pipe and also to form an inner wall between adjacent reinforcing ribs.

A flexible tube including a sheath having a corrugated outer surface wherein a path of intersection of the corrugated outer surface with a plane passing through a center axis of the tube corresponds to a curve having undulations defining a number of hollow portions and rounded zones interconnecting adjacent hollow portions. The rounded zones have at each point an osculating circle having a center situated on a same side of the sheath and a non-infinite radius of curvature. At least one laterally...

Convoluted tubing of polytetrafluoroethylene and the like reinforced by a braid in convoluted form incorporated with the body of polytetrafluoroethylene material as an integral part of the tubing wall structure, particularly for use as an inner core or liner member of an armored, flexible hose assembly.

A flexible conduit having a helical wire reinforcement embedded in the wall thereof; the reinforcement being of a character to normally place the conduit in its axially contractile condition, yet permitting axial extension as required and restoration to its contractile condition; together with a method of making such a conduit. The convolutions of the helical wire reinforcement being under torsional stress whereby the conduit in its contractile state has pleat forming wall portions between succe...