Abstract: A method of making a filament wound pressure vessel. A thermoplastic liner is filament wound with a commingled roving containing thermoplastic and reinforcing filaments. The wound tank is partially filled with a cooling liquid and the wound tank is heated to a temperature which is sufficient to vaporize a portion of the liquid to pressurize the liner at a preselected set pressure and sufficient to fuse the thermoplastic matrix, but insufficient to significantly soften the liner.

Abstract: A quick-release fitting assembly has a male fitting and a female fitting. The male and female fittings are secured together by a retaining ring that is at least partially received in aligned first and second retaining grooves that are provided in the male fitting and the throat of the female fitting respectively. A water tight seal is provided by an O-ring that is retained in a sealing groove of the male fitting and radially compressed against the throat wall when the male fitting is inserted in the female fitting. The water tight seal remains substantially intact when the male fitting is rotated relative to the female fitting. In a preferred embodiment, the male fitting is removable from the female fitting by first compressing the retaining ring so that it no longer extends into the second retaining groove.

Abstract: A method of making a filament wound pressure vessel. A thermoplastic liner is filament wound with a commingled roving containing thermoplastic and reinforcing filaments. The wound tank is partially filled with a cooling liquid and the wound tank is heated to a temperature which is sufficient to vaporize a portion of the liquid to pressurize the liner at a preselected set pressure and sufficient to fuse the thermoplastic matrix, but insufficient to significantly soften the liner.

Abstract: A method of molding a hollow, reinforced molded plastic article. A preform is provided in the shape of the article to be molded. The preform comprises randomly commingled, short lengths of thermoplastic and reinforcing fibers loosely bonded together. A core is provided within the preform and may either be a flexible inflatable core which may be removed later or a thermoplastic liner. The preform is placed in a mold and heated to fuse the thermoplastic while a pressurized liquid coolant is circulated within the core.

Abstract: A quick-release fitting assembly has a male fitting and a female fitting. The male and female fittings are secured together by a retaining ring that is at least partially received in aligned first and second retaining grooves that are provided in the male fitting and the throat of the female fitting respectively. A water tight seal is provided by an O-ring that is retained in a sealing groove of the male fitting and radially compressed against the throat wall when the male fitting is inserted in the female fitting. The water tight seal remains substantially intact when the male fitting is rotated relative to the female fitting. In a preferred embodiment, the male fitting is removable from the female fitting by first compressing the retaining ring so that it no longer extends into the second retaining groove.

Abstract: A method of manufacturing hollow, fiber reinforced thermoplastic composite articles, such as a pressure vessel, is disclosed. The thermoplastic binder is chosen to bind the reinforcing fibers together, to provide strength, and to provide ease of manufacture. The method includes placing a preform with an inflatable core into a mold, pressurizing the inflatable core, and heating the mold to enable the thermoplastic binder to melt and distribute throughout the preform, binding the reinforcing fibers. The article is then cooled and removed from the mold, resulting in a hollow molded article. The inflatable core may be removed from the article and reused, or the core may become an integral part of the finished article.

Abstract: A method of molding a hollow, reinforced molded plastic article. A preform is provided in the shape of the article to be molded. The preform comprises randomly commingled, short lengths of thermoplastic and reinforcing fibers loosely bonded together. A core is provided within the preform and may either be a flexible inflatable core which may be removed later or a thermoplastic liner. The preform is placed in a mold and heated to fuse the thermoplastic while a pressurized liquid coolant is circulated within the core.

Abstract: A filament-wound pressure vessel is disclosed which has a reinforced access opening. The pressure vessel comprises a blow-molded one piece liner having an outer surface defined by a cylindrical sidewall and oblate ellipsoidal ends. The liner defines at least one access opening into the vessel and the access opening has a cylindrical neck portion and a liner flange extending radially outwardly from an open distal end of the neck portion. A cylindrical reinforcement member surrounds the cylindrical neck portion and has a supporting flange at one end thereof, which engages and annular face of the liner flange. The reinforcement member has a radially extending supporting foot at the other end thereof, which contacts the outer surface of the liner. The reinforcement member comprises a plurality of separable arcuate segments so that it may be assembled around the cylindrical neck portion of the liner. A resin-impregnated filament-winding covers the liner and the supporting foot of the reinforcement member.

Abstract: A method and apparatus for attaching an insert in an opening in a molded thermoplastic body. The insert includes a thermoplastic mounting portion which is fused with the thermoplastic material of the body. The insert is maintained in a spaed position from the opening during the heating portion of the molding cycle and positioned within the opening while the thermoplastic material is still sufficiently hot to fuse with the thermoplastic mounting portion of the insert.

Abstract: A filament-wound vessel for containing corrosive and pressurized fluids is disclosed. The vessel comprises a thermoplastic resin inner liner having a cylindrical sidewall and integral oblate, ellipsoidal end sections, and axially aligned access openings at each end of the vessel. One of the openings has a relatively wide diameter compared to the other opening, and a tank fitting is mounted in the wide diameter opening. The tank fitting comprises a fiber-reinforced plastic female member having a cylindrical end projecting into the wide diameter opening of the inner liner and a cylindrical neck portion projecting from the opening. An annular boss is provided between the cylindrical end and the cylindrical neck and rests on an exteriorly facing annular portion of the end section. A sealing ribbon, which comprises a substantially uniform mixture of a thermoplastic material and ferromagnetic particles, seals the boss to the annular portion upon the application of electromagnetic energy.

Abstract: There is disclosed apparatus for rotationally casting a plastic liner for a pressure vessel having a metal access fitting molded therein. The apparatus includes a rotational casting arm having a mold supporting surface and adapted to be rotated about orthogonal axes. A hollow mold having a mold cavity surface conforming to the outside surface of the liner to be molded is removably attached to the mold supporting surface together with a metal access fitting. The metal access fitting has a longitudinal axis aligned with one of the orthogonal axes and has at least a first surface portion extending into the mold cavity. The first surface portion and the surface of the mold cavity are coated with plastic upon mold rotation to form the plastic liner.

Abstract: A split tank closure and diaphragm assembly for a hydropneumatic filament wound pressure vessel is disclosed. The assembly includes first and second cup shaped plastic tank liners having oblate ellipsoidal end portions and cylindrical sidewall portions terminating in cylindrical open mouth portions. A ring is provided for joining and sealing the open mouth portions together to form a sealed container and to mount a diaphragm within the tank to divide the interior of the tank into variable volume chambers. The ring has a cylindrical outer surface corresponding to the outside diameter of the cylindrical sidewall portions of the liners. The liners form a dovetail joint with the ring and respectively trap an O-ring and a bulbous portion of the diaphragm between recessed portions of the liner and a surface of the ring to seal the interior of the tank. The assembly is wound with a resin impregnated continuous roving to reinforce the tank and resist internal pressures.

Abstract: A tank closure assembly adapted to releasably couple tank sections formed by transversely splitting an integral bag-molded fiber-reinforced tank. According to one aspect of the invention, the assembly includes external circumferential flanges secured to the tank sections adjacent their severed faces and in opposed relation to each other. An O-ring seal, disposed externally of the tank sections and between the flanges, is compressed into sealing engagement with surrounding surfaces, by tightening of a circumferential band encircling the flanges, to seal the tank sections at their plane of separation. According to another aspect of the invention, the assembly includes a unitary clamping band having hooked ends which engage grooves adjacent the severed faces of the tank sections and the clamping band retains a pair of O-rings which seal the tank at their plane of separation.

Abstract: A tank closure assembly adapted to releasably couple tank sections formed by transversely splitting an integral bag-molded fiber-reinforced tank. The assembly includes external circumferential flanges secured to the tank sections adjacent their severed faces and in opposed relation to each other. An O-ring seal, disposed externally of the tank sections and between the flanges, is compressed into sealing engagement with surrounding surfaces, by tightening of a circumferential band encircling the flanges, to seal the tank sections at their plane of separation. A method of machining a tank to simultaneously form the split sections and suitable flange receiving grooves thereon is disclosed, as well as a method of pressure-testing the machined tank sections prior to assembly of the flanges and O-ring seal.