Abstract: A mechanism for restraining 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 featuring an improved restraint mechanism. The restraint mechanism includes a circumferential casing and a companion grip ring, both of which are received within a mating groove provided in the belled end of a female pipe. The grip ring is made up of a series of arc-shaped gripping elements which are interconnected by discrete elastomeric segments. The gripping elements are separated by gaps so that a flexible hinge region is created by the elastomeric segments between adjacent gripping elements. The elastomeric segments provide both axial and radial spring action to the assembly.

Abstract: A restrained pipe joining system for plastic pipe is shown comprising male and female ends each having aligned circumferential grooves which form a canal for passage of a locking keystrap. The keystrap can be formed of PEEK or PEEK reinforced with glass fiber. During manufacture, the female belled end is sequentially formed over a Rieber style gasket and then over a ring-shaped casing member. The casing member is also formed from polymeric composite materials. In some cases, the casing is reinforced with an internal metal band.

Abstract: A method of manufacturing a sealing gasket is shown for use in a pipe sealing system. A pair of mating upper and lower mold plates are provided each having an exposed molding surface in the form of a spiral cavity. A length of pre-extruded elastomeric material in the shape of the near final form of the spiral mold cavity is laid into the mold cavities to substantially fill the cavities. The material may have hardened gripping elements incorporated therein. The upper and lower mold plates are closed to compress the elastomeric material within the spiral cavities and thereafter the material is cured to form a spiral strip. The spiral strip is then cut into given lengths having opposing free ends and the free ends are spliced to form completed sealing gaskets of a desired size.

Abstract: A pipe sealing gasket is shown which is designed to be received within a raceway provided within the female, belled end of a section of plastic pipe which is assembled with a mating male pipe end to form a plastic pipe joint. The gasket is a two-component gasket having a softer, elastomeric portion and a harder, plastic ring portion. A splicing technique is used to form the softer, elastomeric portion with the harder, plastic portion being injection molded over the previously formed elastomeric portion.

Abstract: A mechanism for restraining 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 featuring an improved restraint mechanism. The restraint mechanism includes a circumferential casing and a companion grip ring, both of which are received within a mating groove provided in the belled end of a female pipe. The grip ring is made up of a series of arc-shaped gripping elements which are interconnected by discrete elastomeric segments. The gripping elements are separated by gaps so that a flexible hinge region is created by the elastomeric segments between adjacent gripping elements. The elastomeric segments provide both axial and radial spring action to the assembly.

Abstract: A method is shown for manufacturing a hardened gripping element for a sealing and restraint system used for forming a pipe joint in a fluid pipeline. Instead of machining the gripping elements used in the system from a metal stock, a special series of metal injection molding steps are utilized. A metal polymer composite mix is first formed having a metal particulate phase and a polymer phase. A green metal composite article is formed by either extruding the composite mix or molding the composite mix into a metal polymer composite article having at least one gripping surface having a plurality of gripping teeth. The composite article is subjected to thermal debinding and sintering to produce a finished or near finished hardened gripping element.

Abstract: A pipe sealing gasket is shown which is designed to be received within a raceway provided within the female, belled end of a section of plastic pipe which is assembled with a mating male pipe end to form a plastic pipe joint. The gasket is a two-component gasket having a softer, elastomeric portion and a harder, plastic ring portion. A splicing technique is used to form the softer, elastomeric portion with the harder, plastic portion being injection molded over the previously formed elastomeric portion.

Abstract: A pipe belling process where a heated thermoplastic pipe end is forced over a sealing gasket on a forming mandrel, with the pipe being subsequently cooled to retain the gasket in an internal groove simultaneously formed in the pipe end. The sealing gasket is a two-component gasket with an elastic component and a plastic component. The elastic component is stretched over a portion of the plastic component during assembly with the plastic component acting as a belling ramp for the gasket during the subsequent pipe belling operation.

Abstract: A pipe sealing gasket is shown which is designed to be received within a raceway provided within the female, belled end of a section of plastic pipe which is assembled with a mating male pipe end to form a plastic pipe joint. The gasket is a two-component gasket having a softer, elastomeric portion and a harder, plastic ring portion. A splicing technique is used to form the softer, elastomeric portion with the harder, plastic portion being injection molded over the previously formed elastomeric portion.

Abstract: A method is shown for manufacturing a hardened gripping element for a sealing and restraint system used for forming a pipe joint in a fluid pipeline. Instead of machining the gripping elements used in the system from a metal stock, a special series of metal injection molding steps are utilized. A metal polymer composite mix is first formed having a metal particulate phase and a polymer phase. A green metal composite article is formed by either extruding the composite mix or molding the composite mix into a metal polymer composite article having at least one gripping surface having a plurality of gripping teeth. The composite article is subjected to thermal debinding and sintering to produce a finished or near finished hardened gripping element.

Abstract: A pipe sealing gasket is shown which is designed to be received within a raceway provided within the female, belled end of a section of plastic pipe which is assembled with a mating male pipe end to form a plastic pipe joint. The gasket is a two-component gasket having a softer, elastomeric portion and a harder, plastic ring portion. A splicing technique is used to form the softer, elastomeric portion with the harder, plastic portion being injection molded over the previously formed elastomeric portion.

Abstract: A pipe sealing gasket is shown which is designed to be received within a raceway provided within the female, belled end of a section of plastic pipe which is assembled with a mating male pipe end to form a plastic pipe joint. The gasket is made up of a hard plastic band having an outer circumferential surface and an inner circumferential surface, and two separated elastomer portions. A first of the separated elastomer portions forms an outer ring which circumscribes the outer circumferential surface of the hard plastic band. The second of the separated elastomer portions forms an inner lip which circumscribes the inner circumferential surface of the hard plastic band. The two separate elastomer portions are connected during the gasket molding operation by a series of spaced ribs which form a continuous body of elastomer connecting the first and second separated elastomer portions at spaced intervals.

Abstract: A pipe sealing gasket is shown which is designed to be received within a raceway provided within the female, belled end of a section of plastic pipe which is assembled with a mating male pipe end to form a plastic pipe joint. The gasket is made up of a hard plastic band having an outer circumferential surface and an inner circumferential surface, and two separated elastomer portions. A first of the separated elastomer portions forms an outer ring which circumscribes the outer circumferential surface of the hard plastic band. The second of the separated elastomer portions forms an inner lip which circumscribes the inner circumferential surface of the hard plastic band. The two separate elastomer portions are connected during the gasket molding operation by a series of spaced ribs which form a continuous body of elastomer connecting the first and second separated elastomer portions at spaced intervals.

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: 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: 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 method and 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 is provided with a low friction coating.

Abstract: A water pressurization system is shown having a metal tank with a tank interior which is divided into first and second fluid chambers by a flexible membrane. One side of the tank interior is pressurized by compressed air. The membrane has a special coating applied thereto which decreases the natural permeability of the rubber material which is used to form the membrane. By decreasing the permeability of the membrane material, wear and tear on the membrane is decreased. The possibility of deloading the tank interior of pressurized gas due to the membrane permeability is also lessened.