Abstract: A method for manufacturing a gasket that is reinforced by a metal band, which is completely encapsulated within the elastomeric material of the gasket. The metal band is formed with spaced-apart dimples stamped into its inner surface, causing raised projections to form on the outer surface of the metal band. When the metal band is placed in a mold, the raised projections on its outer surface cause the metal band to be spaced apart from the inner wall of the mold. Elastomeric material is then injected into the mold and is able to completely encapsulate the metal band. The gasket is cured and then removed from the mold.

Abstract: A restraining system for connecting a belled end of a female pipe to a spigot end of a male pipe is disclosed. The system includes a ring-shaped casing having circumferential grooves separated by an abutment surface. One or more restraining rings or members are disposed in the grooves so as to contact both the casing and the outer surfaces of the male and female pipes. The one or more restraining rings restrain the pipes from moving away from each other when the system is pressurized.

Abstract: A method for manufacturing a gasket that is reinforced by a metal band, which is completely encapsulated within the elastomeric material of the gasket. The metal band is formed with spaced-apart dimples stamped into its inner surface, causing raised projections to form on the outer surface of the metal band. When the metal band is placed in a mold, the raised projections on its outer surface cause the metal band to be spaced apart from the inner wall of the mold. Elastomeric material is then injected into the mold and is able to completely encapsulate the metal band. The gasket is cured and then removed from the mold.

Abstract: A restrainer for connection to the belled end of a female pipe or fitting. The restrainer has a groove for receiving a compressed, snap-fit gripping ring, constructed from two or more rigid segments joined by elastomeric segments. The gripping ring has rows of teeth on its inner circumference, shaped so the spigot end of a male pipe can be inserted through the restrainer into the belled end of the female pipe. The gripping ring restrains the male pipe from moving in an opposite direction when the system is pressurized. The coupler can be connected to the female pipe in several ways: it can be threaded onto a threaded lip of the pipe; a projection formed on its outer diameter or its inner diameter can be snap-fit into on onto the end of the female pipe; or it can be welded or fused onto the outer end of the female pipe.

Abstract: A pipe sealing gasket is shown which is designed to be received within a groove provided within a socket end of a thermoplastic pipe. The gasket includes a ring shaped body which, when viewed in cross-section includes a leading nose region and a radially inwardly slanting primary sealing surface which forms a lip seal for engaging a mating spigot end during insertion, the primary sealing surface being joined to a secondary sealing surface by an intermediate circumferential groove region, the secondary sealing surface comprising a planar circumferential region which terminates in an inside corner of the gasket, the inside corner being connected to an outermost wall region of the gasket by an exterior gasket surface, the outermost wall region of the gasket being connected to the nose region of the gasket by vertical step which joins a uniformly sloping external gasket surface.

Abstract: A pipe sealing gasket is shown which is designed to be received within a groove provided within a socket end of a thermoplastic pipe. The gasket includes a ring shaped body which, when viewed in cross-section includes a leading nose region and a generally planar lower compression region, the leading nose region being joined to the lower compression region by a leading sloped surface region which forms an alignment ramp to guide a mating spigot end during insertion and which defines an angle .alpha. with respect to a horizontal axis drawn parallel to a central axis of the pipe, the lower compression region being joined to a secondary seal surface by a vertical lip portion which terminates in a trailing surface which defines a second angle .beta. with respect to the horizontal axis drawn parallel to the central axis of the pipe. The presence of the generally planar lower compression region prevents the vertical lip portion from bending backward under pressure loading and wherein the angles .alpha. and .beta.

Abstract: A pipe sealing gasket is shown which is designed to be received within a groove provided within a socket end of a thermoplastic pipe. The gasket includes a ring shaped body which, when viewed in cross-section includes a leading nose region and a lower compression region. The leading nose region is joined to the lower compression region by a leading curved surface region which defines an angle .alpha. with respect to a horizontal axis drawn parallel to the central axis of the pipe. The lower compression region is joined to a secondary seal surface by a trailing curved surface region which defines a second angle .beta. with respect to the horizontal axis drawn parallel to the central axis of the pipe. The angles .alpha. and .beta. are selected to minimize the insertion force required when inserting the male spigot end within the female socket end of the pipe joint while guiding the spigot end and maintaining a compression seal between the pipe sections.

Abstract: A method is shown for installing a pipe gasket within the bell end of a pipe section. The bell end is oriented along a horizontal work axis. The annular gasket is inserted within the mouth opening of the bell end of the pipe. The gasket is oriented at an oblique angle with respect to the horizontal axis, whereby a leading edge of the annular gasket moves past the annular groove provided in the bell end and a trailing edge of the gasket engages the annular groove. A retracting force is exerted on the gasket by pulling the leading edge backwards in the direction of the mouth opening of the bell end of the pipe until the gasket snaps into a lock-in position within the annular groove. The gasket body has an embedded relatively rigid ring which is precisely located to ensure that the gasket, once in snap-fit position, is securely retained within the gasket groove and cannot be displaced.

Abstract: An improved pipe belling process is shown which features a mandrel having spring loaded detents at one circumferential position on an outer working surface. A gasket is installed on the outer working surface in abutment with the exposed detents. The heated socket end of a thermoplastic pipe is forced over the mandrel exterior and over the gasket with the detents in an extended position. This action causes the heated socket end of the pipe to flow over the gasket and form a retention groove for retaining the gasket before again contacting the working surface of the mandrel. The heated end of the pipe is cooled and retracted from the working surface of the mandrel. The retraction step serves to force the spring loaded detents to the retracted position to allow travel of the thermoplastic pipe over the working surface of the mandrel with the gasket being retained within the formed groove.

Abstract: An interlocking restraint plastic pipe joining system is shown which features female and male end connections for adjacent lengths of pipe. The female end connection has at least one radially extending indention or protrusion within the mouth opening thereof. The male end connection has at least one radially extending protrusion or indention formed on an exterior surface thereof. The indention and protrusion matingly engage in snap fit fashion as the joint is formed by forcing the male connection axially into the female connection.

Abstract: A pipe gasket is shown for use in forming a joint made up of an outer pipe having an annular groove therein for receiving the gasket and an inner pipe inserted within the outer pipe. The gasket includes a body formed from a resilient material having an interior and an exterior. The interior of the body includes a first portion formed of a hard, relatively high durometer material which is initially contacted by the inner pipe and a second portion formed of a relatively lower durometer, more flexible material. The second portion includes an inwardly extending projection which forms a primary sealing surface with respect to the inner pipe when the inner and outer pipes are assembled. Because the entry region initially contacted by the inner pipe is formed of a higher durometer material, the gasket tends to securely maintain its position within the outer pipe groove during the installation of the inner pipe.