Abstract: A pressure-resistant helical corrugated pipe comprises a helical corrugated pipe wall having a top portion, opposite side wall portions extending from the top portion and a bottom portion extending from the side wall portions and disposed closed to the axis of the pipe; and belt plates which are formed separately from each other and made of a thin metal. The belt plates are disposed respectively at the side of the top portion and the side of the bottom portion as constituent elements for the pipe wall. The opposite edges of the two metal belt plates are disposed in abutted relation or in spaced opposed relation at the opposite side wall portions. The two metal belt plates are interconnected by connective portions which are made of a synthetic resin or rubber.

Abstract: A pressure-resistant helically corrugated pipe includes an integral, pipe wall corrugation helically wound to form a pipe, the corrugation having a trough portion disposed close to the axis of the pipe and outwardly projecting flange portions on opposite sides of the trough portion, adjacent flange portions being connected together to form the pipe having a helical outwardly projecting portion adjacent the trough portion. The pipe further includes a metal belt plate reinforcing member disposed within the trough portion of the helically disposed corrugation, the metal belt plate being generally U-shaped in cross-section so as to define a base, legs and free ends and opening toward the exterior of the pipe.

Abstract: A pressure-resistant helical corrugated pipe comprises a helical corrugated pipe wall having a top portion, opposite side wall portions and a bottom portion; a continuous thin metal belt plate of a generally U-shaped transverse cross-section which is disposed in one of the top portion and the bottom portion and also in at least part of the opposite side wall portions extending from the one of the top portion and the bottom portion; another metal belt plate of a flat configuration being disposed in the other of the top portion and the bottom portion and disposed out of contact with the thin metal belt plate; and connective belt regions provided between the two metal belt plates in which the metal belt plates are absent, the connective belt regions being made of a synthetic resin or rubber to interconnect the two metal belt plates.

Abstract: A synthetic resin pipe intended for underground use is disclosed having both an improved strength and flexibility but reduced weight. An inner layer of the body of the pipe is formed of a synthetic resin, and a reinforcing layer is wound around the inner layer. The reinforcing layer is porous, and may be composed of a helically wound punched metal belt, mesh, or the like. An outer layer composed of a helically wound belt of synthetic resin having a high fusibility with the material of the inner layer is formed over the reinforcing layer. A reinforcing rib, forming the corrugations of the pipe, is wound around the outer layer. If desired, the reinforcing rib can be made integral with the belt of the outer layer.

Abstract: A synthetic resin pipe intended for underground use having an increased strength but reduced wall thickness. In accordance with the invention, a reinforcing member, in the form of a perforated belt, is embedded in or fused to the resin material of the pipe and extends along top portions and at least portions of the side walls adjacent to the top portions of the corrugations of the pipe.

Abstract: A flexible hard pipe in which over a soft inner pipe wall a hard belt-like member is helically wound. The belt-like member has a double-hook shape in which a flat inner surface is fused to the inner pipe wall. A raised hook portion overlaps a hook portion of the fused portion of a neighboring wrap.

Abstract: An improved pressure-withstanding pipe according to the invention is made of a soft synthetic resin or rubber material with hard synthetic resin reinforcing bodies helically wound and embedded in the pipe wall at predetermined intervals. A thin reinforcing belt member is also helically wound and embedded in the pipe wall and the opposite side end portions of the belt are anchored in adjacent ones of the rigid reinforcing bodies. The method of manufacturing a pipe according to the invention includes a step of extruding the pipe forming body by feeding rigid synthetic reinforcing material and soft synthetic material to the extruder and, at the same time, passing the thin reinforcing belt member therethrough. The resultant pipe according to the invention is highly resistant to extension and other deformation due to pressure exerted from the material being transported as well as highly resistant to external pressure and deformation from such pressure.

Abstract: A flexible pipe comprising a flexible solid pipe to which is bonded a spirally wound belt having an S-shaped cross section. The two sides of the belt are bent at parallel acute angles and successive wraps are overlapped. Cords may be inserted into the space formed by the flexible corrugation.

Abstract: An improved pressure-withstanding pipe is made of a soft synthetic resin or rubber material with hard synthetic resin reinforcing bodies helically wound and embedded in the pipe wall at predetermined intervals. A thin reinforcing belt member is also helically wound and embedded in the pipe wall and the opposite side end portions of the belt are anchored in adjacent ones of the rigid reinforcing bodies. The method of manufacturing a pipe according to the invention includes a step of extruding the pipe forming body by feeding rigid synthetic reinforcing material and soft synthetic material to the extruder and, at the same time, passing the thin reinforcing belt member therethrough. The resultant pipe according to the invention is highly resistant to extension and other deformation due to pressure exerted from the material being transported as well as highly resistant to external pressure and deformation from such pressure.

Abstract: A pipe made of a synthetic resin and suitable for underground use which has an improved strength and reliability. In a first embodiment, a helical reinforcing rib is provided by extruding together with a band of resin material which forms the main body of the pipe a corrugated tube. By passing the corrugated tube through the extrusion die, the danger of the wall thickness of the main body of the pipe being reduced is eliminated. In a second embodiment, the reinforcing rib is formed by helically winding a reinforcing member having at least an outer coating of either the same material which forms the main body of a straight-wall pipe or a material having a high fusibility therewith. In this case also, the reinforcing rib can be made from a corrugated tube having a semicircular cross-section.

Abstract: An underground drain pipe having an improved soil pressure resisting strength. A main portion of the pipe is constituted by a generally U-shaped strengthening member. The strengthening member is wound in a spiral with the open sides thereof directed inwardly. The strengthening member has flange webs projecting longitudinally from the inward edges thereof. A flat band having holes formed therein is wound around the strengthening member along the gap. The flat band has a plurality of small holes formed therein restricted to the area of the gap. If desired, the interior portions of the strengthening member can be sealed with a second band attached to the opposite side of the flange webs from the band having the holes formed therein.

Abstract: A reinforced underground pipe made of a synthetic resin having an improved strength and reduced resin requirement. The reinforcement of the pipe is constituted by a helical rib formed on the outer surface of the main body of the pipe. At least side wall portions of the rib are corrugated. The rib may be U shaped or have a semicircular cross section. The corrugations may be rectangular, sinusoidal or triangular.

Abstract: A flexible hose composed of a membrane which comprises soft and hard strip members alternatively disposed in a spiral form. A connector element is disposed to extend through the center of the thickness of the soft strip member and bilaterally of the hose in its axial direction. Both the projected portions of the connector element and the hard strip members adjacent the soft strip member are interconnected.

Abstract: A double-walled corrugated synthetic resin pipe comprises a straight inner pipe, and a corrugated outer pipe surrounding the inner pipe, and joined integrally thereto. The inner pipe is formed by a spirally wound flat strip of a synthetic resin having adjoining turns joined to each other along their adjoining edges, and has a generally even outer surface. The outer pipe is formed by a spirally wound corrugated synthetic resin strip also having adjoining turns thereof joined to each other along their adjoining edges. The outer pipe has a corrugation defined by a ridge portion, a groove portion, and an intermediate portion, and the groove portion has an inner surface joined to the outer surface of the inner pipe.

Abstract: A method of making a flexible hose comprising a hose main body formed from a rubber strip wound into helical coils rigidly joined together and a linear reinforcement of rigid resin disposed in contact with the strip in a manner to have a thickness between the reinforcement and the inner surface of the helically wound strip. The reinforcement is bonded to the integral homogeneous rubber portion of the strip.