Abstract: A pipe is disclosed. The pipe may comprise an inner wall, an outer wall coupled to the inner wall and including a plurality of corrugation crests and a plurality of corrugation valleys, and a plurality of slits positioned within the corrugation valleys, wherein the slits may be evenly spaced relative to each other around an entire circumference of the pipe.

Abstract: A coupling for multi-wall, corrugated pipe, the pipe including a corrugated wall having a plurality of primary corrugations, is disclosed. The coupling includes a first pipe section having disposed at one end a bell portion, the bell portion having a bell portion of corrugated wall and an outer wall; a second pipe section having disposed at one end a spigot portion, the spigot portion having a spigot portion of corrugated wall between an inner wall and an outer wall; and a gasket disposed in a groove extending around a circumference of the spigot portion and engaged between the bell portion of corrugated wall and the spigot portion of corrugated wall. A multi-wall, corrugated pipe section, and method for assembling a plurality of multi-wall, corrugated pipe sections, are also disclosed.

Abstract: A coupling for multi-wall, corrugated pipe, the pipe including a corrugated wall having a plurality of primary corrugations, is disclosed. The coupling includes a first pipe section having disposed at one end a bell portion, the bell portion having a portion of the corrugated wall and an outer wall; a second pipe section having disposed at one end a spigot portion, the spigot portion having a portion of the corrugated wall between an inner wall and an outer wall; and a gasket engaged between the corrugated wall of the bell portion and the outer wall of the spigot portion. A multi-wall, corrugated pipe section, and method for assembling a plurality of multi-wall, corrugated pipe sections, are also disclosed.

Abstract: A compact assembly for aligning a coring tool relative to a pipe sidewall. The coring tool includes a hollow, cylindrical hole saw mounted to an arbor that has an elongated pilot shaft centered in the hole saw. The assembly is made up of a base plate that is attachable to the pipe sidewall. In one embodiment, a tubular sleeve is mounted to the base plate and has a bore diameter sized for receiving the pilot shaft as the hole saw is advanced toward and saws through the pipe wall, and the entire assembly is sized to fit inside the hole saw as the hole saw saws through the pipe sidewall. In another embodiment, the base plate is configured for use with pipe sidewalls that include outwardly protruding ribs.

Abstract: The present disclosure is directed to a method of welding a gasket to a spigot portion of a pipe section. The method includes supporting the gasket in a recess on the spigot portion of the pipe section. The gasket includes a seating portion and a sealing portion. The sealing portion includes a first shoulder portion and a second shoulder portion. A first bonding portion extends from the first shoulder portion and a second bonding portion extends from the second shoulder portion. The first bonding portion and the second bonding portion are provided to bond the gasket to the spigot portion. The method further includes heating a portion of the gasket and an adjacent surface of the spigot portion and applying a force onto the portion of the gasket following the application of heat to fuse the gasket onto the spigot portion.

Abstract: A pipe having an axially extending bore defined by a smooth inner wall fused to a corrugated outer wall is provided. The corrugated outer wall has axially adjacent, annular, outwardly-extending crests separated by valleys. The pipe further includes an outer layer fused to the outer wall, the outer layer having adjacent concave portions and convex portions, the concave portions being aligned with corrugation valleys of the outer wall so that each concave portion of the outer layer extends between at least two corrugation crests. A method of improving the resistance to deformation of a corrugated pipe having a smooth inner wall fused to an outer wall defined by annular crests and valleys is also provided.

Abstract: A system is disclosed for manufacturing multi-wall corrugated polymer pipe. The system includes an extruder configured to co-extrude concentric annular tubes; a corrugator configured to form the concentric annular tubes into a dual-wall pipe having a smooth wall and a corrugated wall; a cross-head die configured to extrude an outer wall of pipe onto the corrugated wall of the dual-wall pipe; a vacuum punch configured to penetrate the outer wall of pipe and draw a vacuum between the corrugated wall and the outer wall, such that the outer wall of pipe deforms inward toward the corrugated wall of pipe between bell and spigot portions of the corrugated wall; and a cutter configured to cut the pipe into sections where the vacuum punch deformed the outer wall between the bell and spigot portions of the corrugated wall. A method of manufacturing multi-wall corrugated polymer pipe is also disclosed.

Abstract: A mold is provided for forming a continuously-extruded parison into a corrugated pipe. The mold includes a mold housing having a plurality of bores, a mold cavity having a plurality of annular corrugations, and a plurality of punches. Each punch is disposed in one of the bores and aligned with one of the annular corrugations of the mold cavity. Each punch is also configured to form an aperture in a corrugation of a corrugated pipe in the mold. A continuous extrusion blow molding system and a method are also provided for forming a hollow plastic product and punching a continuously-extruded, blow molded product before it is released from a mold.

Abstract: A method and apparatus is provided for distributing material through a multilayer pipe extrusion die. A first flow passageway, having a first cross-sectional area and extending along a first flow direction, may be connected to a second flow passageway, having a second cross-sectional area substantially the same as the first cross-sectional area of the first flow passageway, to provide a second flow direction different from the first flow direction of the first flow passageway. A conical passageway may extend from the second passageway toward a dispensing outlet. Material may be distributed from the first flow passageway into the second flow passageway. The method and apparatus may generally maintain the same flow properties of the material at a point before and after the connection of the first flow passageway and the second flow passageway. The flow properties of the material may be altered proximate to the outlet.

Abstract: A drainage system for draining a fluid is disclosed. The drainage system includes a drain basin having a tubular body, the tubular body including a lumen, an outer surface, a top end, and a bottom end. The drainage system also includes at least one pipe connected to the tubular body and an end cap coupled to the bottom end of the tubular body, the end cap including a convex surface configured to divert the fluid to the at least one pipe, wherein the convex surface of the end cap is inserted through the bottom end and is disposed within the lumen of the tubular body.

Abstract: A method of deforming an outer wall of polymer pipe is provided. The method includes: forming dual-wall pipe having a smooth wall and a corrugated wall; extruding an outer wall of pipe onto the corrugated wall of the dual-wall pipe; penetrating the outer wall of pipe with a vacuum punch; and drawing a vacuum between the corrugated wall and the outer wall via the vacuum punch; wherein the vacuum drawn between the corrugated wall and the outer wall causes the outer wall to deform in a direction towards the corrugated wall. An apparatus for forming an outer wall of pipe and a mold configured to form a coupling preform in a segment of continuously-extruded and molded polymer pipe are also provided.

Abstract: A method of pressing an outer wall of polymer pipe is provided. The method includes extruding a layer of polymer onto a pipe to form an outer wall of pipe; conveying the pipe including the outer wall of pipe through a pressing apparatus having a pressing element configured to rotate about the pipe; and urging the pressing element against an exterior surface of the outer wall as the pressing element rotates about a pipe conveyed through the pressing apparatus. An apparatus for pressing an outer wall of polymer pipe is also provided.

Abstract: An end section or cap for a stormwater containment assembly includes a substantially half-dome-shaped body member and a connector disposed on the body member along a periphery or perimeter thereof, for coupling the body member to a stormwater chamber wall. The body member has a smooth convex outer surface with an absence of reinforcement ribs and also has a smooth concave inner surface with an absence of reinforcement ribs.

Abstract: An extrusion die configured to have an interior chamber sealed from the atmosphere is disclosed. The extrusion die includes an extrusion die head disposed at a downstream end of the interior chamber; and a vacuum seal disposed at an upstream end of the interior chamber; wherein the vacuum seal is configured to selectively form a seal between the extrusion die and a product disposed in the interior chamber. The vacuum seal includes an annular sealing surface disposed at an inner diameter of the vacuum seal; a hollow, interior chamber; and a plurality of bellows disposed between the annular sealing surface and the extrusion die; wherein the vacuum seal is configured to selectively form a seal between the extrusion die and a product disposed in the interior chamber. A method of selectively sealing an end of an extrusion die is also disclosed.

Abstract: A pipe extrusion die may be provided having an inner flow passageway having a first cross-sectional area, and an outer flow passageway having a second cross-sectional area, both being in communication with an inlet flow passageway. A ratio adjusting tube may be movably disposed in blocking engagement between the inlet flow passageway and the inner flow passageway. The ratio adjusting tube and the outer flow passageway both may be substantially concentric with the inner flow passageway. Material may be distributed from the inlet flow passageway to the inner and outer flow passageways. The method and apparatus may allow for the manual and automatic control of the proportion of material distributed between the inner and outer flow passageways by adjusting the position of the ratio adjusting tube in relation to a passageway between the inlet flow passageway and the inner flow passageway, based on various operating parameters.

Abstract: A plastic pipe coupler is provided having a plurality of sections connected to one another but with at least one gap between the ends of two sections which are adjacent to one another. Each of the coupler sections has an exterior surface and an interior surface, and is fabricated so that when taken together, the sections cooperatively circumvent a section of plastic pipe. Each bracket is secured to the exterior surface of one of the aforesaid sections of the coupler and has a base plate, a pair of sidewall plates attached to each base plate, and a crosspiece having a first end and a second end, the first end of which is in contacting relationship with one of the pair of sidewall plates, while the second end is in contacting relationship with the other of the pair of sidewall plates.

Abstract: A composition and method for a single or dual wall extruded and thermoformed pipe corrugated HDPE pipe composed of a thermoplastic HDPE that is subsequently cross-linked by introducing moisture. The typical thermoplastic HDPE utilized for blow molding to fabricate the corrugated pipe is cross-linked to enhance dimensional stability, stress crack resistance, impact, creep resistance, and stiffness. The method also may comprise obtaining the enhanced properties by cross-linking the already fabricated linear HDPE corrugated pipe. The cross-linked HDPE is produced using a silane processing method. A composition may comprise a high density polyethylene compound composed with about 1 to 15 percent of finely ground isotropic cross-linked polyethylene recycle.

Abstract: 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 resistance to deformation.

Abstract: A pipe having an axially extending bore is defined by a corrugated outer wall having alternating, axially-adjacent, annular crests and valleys. The wall of the pipe has a hole disposed in a valley which provides fluid communication between the bore and the outside. The pipe also has a cover which extends between and is attached to axially adjacent crests. The cover is disposed over the hole to prevent material in which the pipe may be disposed from obstructing the hole and permitting fluid flow through the hole.

Abstract: An annular gasket for affecting a watertight seal between two sections of corrugated pipe. The gasket comprises a seating portion dimensioned to fit within an annular recess in one of the mated sections of corrugated pipe, and a sealing portion integrally molded with the seating portion. The sealing portion includes a first shoulder portion, a second shoulder portion, and an arcuate surface extending between the first and second shoulder portions. The mass of the seating portion is less than the mass of the sealing portion.