Abstract: A coupling for joining socket ends of multilayer tubing through electrofusion including a central body having opposing male ends. A core at least partially surrounds the central body and an outer layer encloses the core and central body. The outer layer defines a flange protruding radially outwardly from the central body, wherein the core includes a portion that extends radially outwardly through the flange and out of the flange so that the core can be directly heated by an external heating element.

Abstract: A tubing assembly including elongated first and second tubes for carrying a fluid flow. Each tube is a composite tube having an inner layer, a middle layer surrounding the inner layer, and an outer layer surrounding the middle layer. At the end of each tube, the tubes are flared outward from an axis of the tubes in complimentary shapes with the middle layer being directed away from the fluid flow and following a contour of the inner layer. The tubing assembly may include a gasket provided intermediate the inner layers. A clamp compresses the ends together and the gasket (if provided) to create a joint between the inner layers of the ends and maintain a seal between the inner layers of the flared ends.

Abstract: A joining method wherein ends of multilayer composite tubing and/or fittings having at least one middle layer of malleable metal are flared radially outwardly so that exposed ends of the middle layer of malleable metal are directed radially outward and away from a fluid flow path within the tubing and/or fittings. The flared-out ends are then fused using infrared butt welding so that the resulting bead protrusion into the fluid flow path is small enough to be acceptable for use in a high purity water system.

Abstract: A saddle wye for connecting a branch pipe to a heat fusible thermoplastic main pipe, including a heat fusible thermoplastic saddle shaped and adapted to be received on the main pipe. The saddle includes top and bottom surfaces and an opening extending between the top and bottom surfaces for alignment with an opening in the main pipe. A branch extension extends at an acute angle from the top surface of the saddle such that a first open end of the branch extension is connected the opening of the saddle and a second open end of the branch extension extends above an end of the saddle. A resistance heating wire is secured to the bottom surface of the saddle around the opening of the saddle in a pattern that includes a parabola. The wire pattern assures that fusion occurs close to the opening in the saddle to prevent fluid from reaching between the saddle and a sidewall of the main pipe as fluid travels between the branch pipe and the main pipe.

Abstract: An anchor support is provided for a double-containment piping assembly having at least one outer piping component defining a first diameter, and at least one inner piping component received within the at least one outer piping component and defining a second diameter less than the first diameter and forming an approximately annular space between the inner and outer piping components. The anchor support has a cylindrical outer-component support section defining a first approximately annular support surface having a first diameter approximately equal to the first diameter of the at least one outer piping component for contacting and supporting the outer piping component. An approximately cylindrical inner-component support section of the anchor support is spaced laterally relative to, and located approximately at an opposite end of the anchor support relative to the outer-component support section.

Abstract: An anchor support is provided for a double-containment piping assembly having at least one outer piping component defining a first diameter, and at least one inner piping component received within the at least one outer piping component and defining a second diameter less than the first diameter and forming an approximately annular space between the inner and outer piping components. The anchor support has a cylindrical outer-component support section defining a first approximately annular support surface having a first diameter approximately equal to the first diameter of the at least one outer piping component for contacting and supporting the outer piping component. An approximately cylindrical inner-component support section of the anchor support is spaced laterally relative to, and located approximately at an opposite end of the anchor support relative to the outer-component support section.

Abstract: In a closure fitting assembly two identical fittings are adapted to be coupled together in a mirror-image relationship for closing a gap between containment components in a double-containment system. Each fitting defines a first axially-extending fusion surface located on one side of the fitting; a second axially-extending fusion surface located on an opposite side of the fitting relative to the first axially-extending fusion surface; a first circumferentially-extending fusion surface located on one end of the fitting; and a second circumferentially-extending fusion surface located on an opposite end of the fitting. Axially-extending fusion wires are interposed within the seams formed between opposing axially-extending fusion surfaces, and circumferentially-extending fusion wires are seated against each circumferentially-extending fusion surface for receiving electric current to heat the wires and in turn fuse opposing surfaces together.

Abstract: A double-containment piping assembly has two anchor supports, and at least one elbow fitting with an outer elbow section and an inner elbow section received within the inner elbow section. A first leg having a first inner pipe received within a first outer pipe is coupled between an anchor support and the elbow fitting. A second leg having a second inner pipe received within a second outer pipe is coupled between the other anchor support and the other side of the elbow fitting. First flexibility supports are mounted on either side of the elbow fitting, and permit axial and lateral movement of the inner pipe relative to the outer pipe in the areas of the elbow. First axial-guiding supports, which permit axial movement of the inner pipe relative to the outer pipe, but prevent lateral movement of the inner pipe, are each mounted a minimum distance from the elbow fitting between the inner and outer pipes.

Abstract: A double-containment piping assembly has two anchor supports, and at least one elbow fitting with an outer elbow section and an inner elbow section received within the inner elbow section. A first leg having a first inner pipe received within a first outer pipe is coupled between an anchor support and the elbow fitting. A second leg having a second inner pipe received within a second outer pipe is coupled between the other anchor support and the other side of the elbow fitting. First flexibility supports are mounted on either side of the elbow fitting, and permit axial and lateral movement of the inner pipe relative to the outer pipe in the areas of the elbow. First axial-guiding supports, which permit axial movement of the inner pipe relative to the outer pipe, but prevent lateral movement of the inner pipe, are each mounted a minimum distance from the elbow fitting between the inner and outer pipes.

Abstract: In a closure fitting assembly two identical fittings are adapted to be coupled together in a mirror-image relationship for closing a gap between containment components in a double-containment system. Each fitting defines a first axially-extending fusion surface located on one side of the fitting; a second axially-extending fusion surface located on an opposite side of the fitting relative to the first axially-extending fusion surface; a first circumferentially-extending fusion surface located on one end of the fitting; and a second circumferentially-extending fusion surface located on an opposite end of the fitting. Axially-extending fusion wires are interposed within the seams formed between opposing axially-extending fusion surfaces, and circumferentially-extending fusion wires are seated against each circumferentially-extending fusion surface for receiving electric current to heat the wires and in turn fuse opposing surfaces together.

Abstract: A centering support for a double-containment pipe assembly is adapted to support a plurality of primary pipes within a single containment pipe. A first support half of the centering support defines a plurality of first curved support surfaces for supporting one or more primary pipes, wherein each first curved support surface is defined by a radius greater than or equal to the outside radius of the primary pipe to be supported by the respective support surface. A second support half of the centering support similarly defines a plurality of second curved support surfaces for supporting one or more primary pipes, and each second curved support surface is defined by a radius greater than or equal to the outside radius of the primary pipe to be supported by the respective support surface.

Abstract: A double-containment piping assembly has two anchor supports, and at least one elbow fitting with an outer elbow section and an inner elbow section received within the inner elbow section. A first leg having a first inner pipe received within a first outer pipe is coupled between an anchor support and the elbow fitting. A second leg having a second inner pipe received within a second outer pipe is coupled between the other anchor support and the other side of the elbow fitting. First flexibility supports are mounted on either side of the elbow fitting, and permit axial and lateral movement of the inner pipe relative to the outer pipe in the areas of the elbow. First axial-guiding supports, which permit axial movement of the inner pipe relative to the outer pipe, but prevent lateral movement of the inner pipe, are each mounted a minimum distance from the elbow fitting between the inner and outer pipes.

Abstract: An elbow fitting for a double-containment assembly has an inner elbow section contained within an outer elbow section, and the inner elbow section is coupled to corresponding straight sections of inner pipe and the outer elbow section is coupled to corresponding straight sections of outer pipe. The inner elbow section defines a first centerline radius of curvature or a first centerline-to-end radius, and the outer elbow section defines a second centerline radius of curvature or a second centerline-to-end radius. The first centerline radius of curvature is greater than the second centerline radius of curvature, and the first centerline-to-end radius is greater than the second centerline-to-end radius, forming an expanded outer annulus space in comparison to the inner annulus space. The annulus between the inner and outer elbow sections is unobstructed permitting movement of the inner and outer elbow sections relative to each other.

Abstract: A centering support for a double containment pipe assembly of an inner pipe located within an outer pipe, has a first half defining a first surface substantially conforming to the outer surface of the inner pipe, and a second half defining a second surface substantially conforming to the outer surface of the inner pipe. The first and second surfaces are seated on the outside surface of the inner pipe, and the first and second halves are coupled together by at least one fastening member for coupling the centering support to the inner pipe.

Abstract: A centering support for a double-containment piping assembly has a body portion including an inner surface defining a central aperture for receiving and supporting the inner pipe within the outer pipe, and the inner surface is defined by a first radius of curvature. A plurality of support lugs are spaced apart from each other and project outward from the body portion, and each support lug defines an outer support surface for contacting the outer pipe. The support lugs also define corresponding recessed surfaces extending between adjacent support lugs, and each recessed surface is defined by a second radius of curvature substantially concentric with the first radius of curvature.

Abstract: An underground double containment system consists of a concrete outer containment receptacle housing a primary fluid flow pipe which extends therethrough and is slidably supported on double I-beam structures within the concrete receptacle. The concrete receptacle can be provided with a removable cover providing access to the primary piping in modular sections defined by the boundary of the receptacle. The primary piping can expand or move along the longitudinal axis of the concrete receptacle relative to the concrete receptacle enabling thermal of the primary and containment piping outside of the receptacle, which can be formed from different materials, as the outer containment pipe can be connected to the interior of the receptacle at the juncture of the receptacle and the primary piping. A plurality of concrete receptacles can be joined at an angle of between 0.degree. and 180.degree. to provide a double containment system for nonlinear primary pipes.

Abstract: The centering support assembly features a half moon shaped support base with two upright stanchions at opposite sides of the base, providing proper spacing between the base support and a crosshead clamping piece. The entire assembly is bolted together by bolts received through the crosshead and each stanchion, which is threadedly received in the base. One or more inner or primary pipes may be supported between the stanchions, which permit proper deflection of the pipes relative to each other and lateral deflection, if necessary, and similarly, relative to the outer containment pipe. The cross-piece and half moon base portion of the centering support assembly fit within the inner diameter of the outer containment pipe, with the crosshead piece spaced from the inner diameter to permit deflection of the outer pipe relative to the primary pipe or pipes under load.

Abstract: An underground double containment system consists of a concrete outer containment receptacle housing a primary fluid flow pipe which extends therethrough and is supported on inverted T-beam structures within the concrete receptacle. The concrete receptacle can be provided with a removable cover providing access to the primary piping in modular sections defined by the boundary of the receptacle and flexible curved tubes opening in the wall of the receptacle through which the primary piping module sections can be removed from the receptacle or held for repair/maintenance.

Abstract: A double containment pipe joint assembly is provided with an inner pipe and an outer or containment pipe secured in concentric relation. The pipe joint assembly includes a fitting having end surfaces on concentric flanges which can be secured to a length of a primary and containment pipe at intervals along the pipeline wherein sections of the pipeline can be removed and repaired without the necessity of removing the whole pipeline. The concentric flanges are joined by a thickened divider ring which provides smooth fillets at its juncture with the flanges to reduce thermal stresses on the fitting.

Abstract: A centering support for a double containment pipe assembly consists of a three-piece assembly including an outer ring and a pair of mirror-image inner rings having tabs which are inserted into holes in the outer ring from opposite sides. The diameter of the outer ring is slightly smaller than the inner diameter of the outer pipe or conduit of the double containment pipe assembly and is inserted into an outer pipe at spaced locations therealong. The inside diameter of the inner rings are slightly wider than the outside diameter of the primary or inner pipe and they may receive therethrough the inner pipe. The inner rings and outer ring can be formed from dissimilar materials which are weldable to the outer pipe and inner pipe, respectively, at selected support points.