Abstract: A pipe sealing gasket is shown which is designed to be received within a raceway provided within a socket end of a female bell plastic pipe end which is assembled with a mating male spigot pipe end to form a plastic pipe joint. The raceway in the female bell plastic pipe end is preformed during manufacture and the gasket is installed thereafter. The gasket has a rubber body portion which is reinforced by a hard corrugated ring-shaped insert. The hard corrugated ring-shaped insert acts to prevent extrusion of the gasket during a variety of pressure conditions as well as preventing displacement during field assembly.

Abstract: An anti-fatigue mat/shock pad has a mat body with a top surface, a bottom surface, a left side edge, a right side edge and a top and bottom edges. The top and bottom surface of the mat have raised regions thereon which are made up of longitudinally extending raised ribs arranged in parallel fashion with respect to one another and spaced apart a selected distance by longitudinal channels. The longitudinal ribs on the top surface are offset from the longitudinal ribs on the bottom surface in an alternating fashion so that they present a staggered array when viewed in cross section. This particular pattern of raised ribs on the top and bottom surfaces of the mat produces a non-linear deformation pattern under impact forces in use, such as would be caused by athletes running or jumping on an athletic field.

Abstract: A pipe joining system and pipe joint are shown m which two sections of molecularly oriented pipe are joined using heat shrinking techniques. A first section of pipe is provided having a straight, pre-formed socket with an internal diameter and with an end opening having enough clearance to allow a mating spigot section having a given external diameter to be inserted into the socket end opening. After the spigot end is inserted to a given depth, the socket is heated sufficiently so that the internal diameter of the socket end comes into contact with the external diameter of the spigot end, the molecularly oriented pipe being in a rubbery state and exhibiting a low elastic modulus which allows the socket end to conform tightly to the spigot end external diameter without deforming the spigot end.

Abstract: An anti-fatigue mat/shock pad has a mat body with a top surface, a bottom surface, a left side edge, a right side edge and a top and bottom edges. The top and bottom surface of the mat have raised regions thereon which are made up of longitudinally extending raised ribs arranged in parallel fashion with respect to one another and spaced apart a selected distance by longitudinal channels. The longitudinal ribs on the top surface are offset from the longitudinal ribs on the bottom surface in an alternating fashion so that they present a staggered array when viewed in cross section. This particular pattern of raised ribs on the top and bottom surfaces of the mat produces a non-linear deformation pattern under impact forces in use, such as would be caused by athletes running or jumping on an athletic field.

Abstract: A pipe joining system and pipe joint are shown in which two sections of plastic pipe, particularly molecularly oriented pipe, are joined. A first section of plastic pipe has a female, belled pipe end with a mouth opening and having an exterior surface, an interior surface and having an interior circumferential recess formed in the belled pipe end adjacent the mouth opening on the interior surface thereof. A second section of plastic pipe having a mating male plastic pipe end has an interior surface and exterior surface. The exterior surface has a circumferential groove formed at one circumferential location thereof which is alignable with the interior recess formed within the mouth opening of the belled pipe end as the pipe joint is made-up. The circumferential groove is formed during the manufacture of the plastic pipe by expanding the pipe against a restraining element located in the interior of an expansion mold.

Abstract: A pipe sealing gasket is shown which is designed to be received within a raceway provided within a socket end of a female bell plastic pipe end which is assembled with a mating male pipe end to form a plastic pipe joint. The raceway in the female bell plastic pipe end is preformed during manufacture and the gasket is installed thereafter. The gasket has a rubber body portion which is reinforced by a hard plastic band formed as a series of integral, spaced wedges which are interconnected by a flexible ribbon. The hard plastic band acts to prevent extrusion of the gasket during a variety of pressure conditions as well as preventing displacement during field assembly.

Abstract: A method and sealing gasket are shown for providing a sealing joint between a spigot section and a socket section of low pressure plastic pipe, such as drain waste vent pipe that require a minimum of tools and operational steps to complete. The sealing gasket is installed in one of the sections to be joined and the spigot section is inserted within a mouth opening of the socket section with the sections being pressed together in a single operation, thereby forming both the joint and the seal. The sealing gasket is a composite gasket made with one section of a hard plastic material and one section of a thermoplastic elastomer material. No glue or adhesive is required.

Abstract: A pipe sealing gasket is shown which is designed to be received within a raceway provided within a socket end of a female bell plastic pipe end which is assembled with a mating male pipe end to form a plastic pipe joint. The raceway is preformed about the gasket during the pipe belling operation. The gasket has a rubber body portion which is reinforced by a hard plastic band formed as a series of integral, spaced wedges which are interconnected by a flexible ribbon. The hard plastic band acts to prevent extrusion of the gasket during a variety of pressure conditions as well as preventing displacement during field assembly.

Abstract: A pipe sealing gasket is shown which is designed to be received within a raceway provided within a socket end of a female bell plastic pipe end which is assembled with a mating male pipe end to form a plastic pipe joint. The raceway in the female bell plastic pipe end is preformed during manufacture and the gasket is installed thereafter. The gasket has a rubber body portion which is reinforced by a hard plastic band formed as a series of integral, spaced wedges which are interconnected by a flexible ribbon. The hard plastic band acts to prevent extrusion of the gasket during a variety of pressure conditions as well as preventing displacement during field assembly.

Abstract: A pipe sealing gasket is shown which is designed to be received within a raceway provided within a socket end of a female bell plastic pipe end which is assembled with a mating male pipe end to form a plastic pipe joint. The raceway is preformed about the gasket during the pipe belling operation. The gasket has a rubber body portion which is reinforced by a hard plastic band formed as a series of integral, spaced wedges which are interconnected by a flexible ribbon. The hard plastic band acts to prevent extrusion of the gasket during a variety of pressure conditions as well as preventing displacement during field assembly.

Abstract: An improved pipe belling process is shown which features a mandrel having a specially designed backup or forming collar. The backup collar has an outer contact surface which forms an undulating pattern when viewed in cross section. The undulating surface reduces the contact area between the outer contact surface of the collar and the lip region of a plastic pipe being belled, thereby lowering the coefficient of friction that exists between the pipe lip region and the collar.

Abstract: An sealing gasket is shown for use in forming joints of plastic pipe. The gasket is formed as a composite elastomeric body with a leading region formed of a thermoplastic elastomer material and with a trailing region formed of a synthetic plastic material. The gasket body has an outer circumferential region provided with a series of recessed pocket which give it a scallop-like appearance. The relatively harder plastic region of the gasket body deforms the associated pipe socket end during manufacture of the pipe end, whereby the gasket is integrally locked within an internal pipe groove in the pipe socket end upon completion of the pipe belling operation.

Abstract: An apparatus for restraining plastic pipe against both internal and external forces at a pipe or fitting connection and to join and seal at least two pipes to form a pipeline is shown featuring an improved restraining and sealing mechanism. The restraining and sealing mechanism includes a circumferential housing and a companion sealing ring which are received within a mating groove provided in the belled end of a female pipe. The circumferential housing has an interior region which contains a gripping ring insert. The sealing ring and housing are integrally located within a belled pipe end during belling operations. Either the exterior of the gripping ring or the interior of the housing or both are provided with a low friction coating.

Abstract: A combination sealing and restraint system for an as-cast ductile iron fitting is shown for both sealing and preventing separation of an iron pipe fitting and a mating male pipe. A ring-shaped body is installed within a mating groove provided in a mouth region of the as-cast fitting after the fitting has been cast at the manufacturing plant. The ring-shaped body is formed of an injection molded elastomeric material and carries a series of gripping segments which have teeth on an inner surface thereof which are designed to engage an outer surface of a mating male pipe. The teeth are oriented to allow movement of the male pipe in a first direction relative to an end opening of the fitting during assembly, but to resist movement in a opposite direction after the fitting joint has been assembled. The gripping segments have shelf regions which are mechanically secured to the elastomeric body of the gasket.

Abstract: An sealing gasket is shown for use in forming joints of plastic pipe. The gasket has a bulbous region which is bisected by a planar region which forms a pair of oppositely extending wing-like flaps. These features of the gasket allow it to be more reliably seated on the working mandrel used to bell a female, thermoplastic pipe end. The wing-like flap portions of the gasket form wiper surfaces for a subsequently installed male, spigot pipe end as the joint is formed.

Abstract: A sealing gasket and pipe coupling system for corrugated pipe where a male pipe end of a male section of corrugated pipe has an axially extending bore defined by a smooth inner wall fused to a corrugated outer wall having axially adjacent, annular, outwardly-extending corrugation ribs separated by corrugation valleys, each corrugation rib having a circumference. The sealing gasket has an annular gasket body with an inner circumferential region which defines a base for the gasket and an outer sealing region, the inner circumferential region of the gasket is received within a selected corrugation valley of the male pipe end. The base of the gasket body includes a pair of laterally extending lips which, when viewed in cross section, extend outwardly across the selected corrugation valley to fit larger valleys and which bend inwardly to fit narrower valleys.

Abstract: An improved pipe belling process is shown which features a mandrel having a specially designed backup or forming collar. The backup collar has an outer contact surface which forms an undulating pattern when viewed in cross section. The undulating surface reduces the contact area between the outer contact surface of the collar and the lip region of a plastic pipe being belled, thereby lowering the coefficient of friction that exists between the pipe lip region and the collar.

Abstract: A method for joining molecularly oriented pipe in which a coupling is provided which is formed of a material other than molecularly oriented pipe, such as ordinary PVC pipe. The coupling if formed as a tubular body with a combination sealing and restraint mechanism located in each of two opposing end openings of the coupling that seal and restrain mating plain spigot ends of the molecularly oriented pipe. Because the coupling is made of a material such as ordinary PVC, the sealing and restraint mechanisms can be installed in internal grooves provided in the coupling interior during normal pipe belling operations without introducing unacceptable levels of stress or strain into the product.

Abstract: A restrained pipe joining system is shown comprising male and female ends each having aligned circumferential grooves which form a canal for passage of a locking key strap. During manufacture, the female belled end is sequentially formed over a Rieber style gasket and then over a ring shaped casing member having an inner circumferential groove formed on its inner circumferential surface. Preferably, the ring shaped casing has circumferentially spaced teeth that act as a pipe stop in cooperation with an outer circumferential groove on the male spigot to index the pipes to be coupled.