Abstract: A crosshead (10b) and a method are provided for extruding a tubular layer of a thermoplastic material, or for coextruding tubular layers of various thermoplastic materials, without incurring a weld line. The crosshead (10b) includes a supply passage (46) which provides an annular flow of thermoplastic material around a mandrel (18b) by providing separate flows that merge distal from a supply passage (52), a first compressive forging passage (72) that provides static mixing by transverse viscous shear, a longitudinal shear mixer (44a) that provides static mixing by longitudinal viscous shear, and a second compressive forging passage (94) that provides static mixing by longitudinal shear, and an extrusion opening (110).

Abstract: A crosshead (10) and a method are provided for extruding a tubular layer of a thermoplastic material, or for coextruding tubular layers of various thermoplastic materials, without incurring a weld line in any of the layers. The crosshead (10) includes a supply passage (42), a distribution passage (46) which provides an annular flow of thermoplastic material around a mandrel (18) by providing separate flows that merge distal from the supply passage (42), a mixing passage (110) which serves as a first static mixer by dividing the stream of thermoplastic material into a plurality of streams (96) and subsequently merging the divided streams, and a forging passage (118) which serves as a second static mixer by compressively forging that thermoplastic material into a cross section of increased area prior to extruding the thermoplastic material through a die opening (38).

Abstract: A novel flange configuration for plastic containers that can be readily rolled or interfolded with a closure to form an interlocking double seam to provide a leak-proof container. A plastic container is described comprising a sidewall and bottom wall forming an open end with an outwardly extending flange surrounding the open end, said flange extending outwardly from a thin peripheral portion adjacent the open end to a thicker terminal portion, said peripheral portion being provided with a fold line of much thinner cross section.

Abstract: A method is disclosed for sealing or closing off the open end of a multilayered tubular structure, especially one having a barrier or low-gas permeable layer, whereby the integrity of said barrier layer is maintained. The method gives rise to a multilayered parison structure which comprises a cylindrical body having a body wall, an open portion terminating at one end thereof and a bottom wall at the opposite end of said body, said body and bottom walls being composed of a plurality of layers bonded together, all the layers of said bottom wall extending fully inwardly in contacting and overlapping relationship with like layers along the longitudinal axis of said cylindrical body, and a balancing member attached to said bottom wall, said member being composed of a single layer material forced therefrom while in a plastic state.

Abstract: A method is disclosed for sealing or closing off the open end of a multilayered tubular structure, especially one having a barrier or low-gas permeable layer, whereby the integrity of said barrier layer is maintained. The method gives rise to a multilayered parison structure which comprises a cylindrical body having a body wall, an open portion terminating at one end thereof and a bottom wall at the opposite end of said body, said body and bottom walls being composed of a plurality of layers bonded together, all the layers of said bottom wall extending fully inwardly in contacting and overlapping relationship with like layers along the longitudinal axis of said cylindrical body, and a balancing member attached to said bottom wall, said member being composed of a single layer material forced therefrom while in a plastic state.

Abstract: A multilayered preform is disclosed for making an open mouth container. The preform has a container-forming portion comprising a circular central area for making the bottom of the container, an annular sidewall-forming portion for the container surrounding add integral with the outer periphery of the central area, a flange connected to the annular portion, said flange having the contour of the rim of the container, said container-forming portion having a predetermined volume to meet dimensional requirements, and a retaining member having an enlarged portion. The preform is an improved structure that is readily adaptable for making containers from the so-called solid state pressure forming process.

Abstract: A container having a novel flange configuration is disclosed that may be readily rolled with a closure to form an interlocking double seam to provide a leakproof container. The flange configuration may be readily interlocked due to its flexibility and resiliency with a closure without the flange being distorted, fractured or cracked. The container includes a peripheral flange connected to and surrounding the opening of the container, the flange having a channel adjacent the sidewall and a complementary bead associated therewith. In one embodiment, the container is made of a thermoplastic material comprising a plurality of superimposed layers, one of which is yieldable, so that when the flange is interfolded the yieldable material is forced outwardly to fill any that exist voids between the flange and closure to form a complete and flexible seal.

Abstract: This invention relates to a plastic or thermoplastic container designed to exhibit non-paneling of its sidewall due to reduction in pressure within the container. The container itself is provided with a yieldable bottom endwall especially constructed to compensate against the effects of reduced internal pressures often experienced after sealing hot fluids and the like. The thermoplastic container herein described is capable of being filled and sealed without paneling or deformation of its sidewall, said bottom endwall being displaceable inwardly, in preference to the sidewall, upon a relative reduction of pressure in the container, said bottom endwall comprising an outer frustoconical surface extending downwardly and inwardly from said sidewall toward the longitudinal axis of the container at an angle between about 5.degree. and 30.degree.

Abstract: One end of an electrode wire is doubled back at least once forming a teardrop shaped loop around a connector with the terminal end of the wire placed adjacent the wire inwardly of the connector. A rounded conductive mass encapsules said terminal end and the wire. This mass suppresses the field generated at the terminal end of the wire, provides mass dampening inwardly of the connector and distributes the load over both sides of said teardrop shaped loop. A converging restraining means may be disposed over and in contact with both sides of said loop intermediate said mass and said connector thereby providing additional dampening and an ultimate limit on loop movement. The connector has a circular groove within which the base portion of the loop is tightly accommodated by crimping the connector thereover. Preferably, the connector should be constructed from a metal having a substantially lower modulus of elasticity than the wire to preserve the cross-sectional stress area of the wire in so crimping.

Abstract: This invention relates to an improved apparatus and method for locking printing plates to a support, e.g., saddle or cylinder, wherein the support includes a body portion having at least two anchoring means as an integral part thereof, at least one of the anchoring means being incorporated on a spring-mounted bar movable under spring tension to engage and lock printing plates to the support. The invention also relates to apparatus and method for mounting printing plates onto a support comprising an actuating assembly for the spring-mounted bar and which is adapted to move the spring-mounted bar between expanded and compressed positions for the mounting. The spring-mounted bar actuating assembly is mounted beneath the peripheral surface of the support and comprises a pivot arm pivotable at or near its midpoint about a pivot block which is mounted beneath the peripheral surface.

Abstract: This invention relates to an improved apparatus and method for locking printing plates to a support, e.g., saddle or cylinder, wherein the support includes a body portion having at least two anchoring means as an integral part thereof, at least one of the anchoring means being incorporated on a spring-mounted bar movable under spring tension to engage and lock printing plates to the support. The invention also relates to apparatus and method for mounting printing plates onto a support comprising an actuating assembly for the spring-mounted bar and which is adapted to move the spring-mounted bar between expanded and compressed positions for the mounting. The spring-mounted bar actuating assembly is mounted beneath the peripheral surface of the support and comprises a pivot arm pivotable at or near its midpoint about a pivot block which is mounted beneath the peripheral surface.