Abstract: A screw closure is associated with a container mouth and is defined by a metal closure body having a closure panel and a peripheral skirt which extends to an inwardly and upwardly directed curl terminating in a free edge. An annular shoulder of the peripheral skirt cooperates with the curl to captively retain therebetween an upper portion of a plastic security ring joined to a lower portion by a line of weakening with the lower security ring portion being prevented from rotating relative to an associated container neck. The terminal end of the curl is seated in a recess of the security ring upper portion in deforming engagement therewith.

Abstract: A screw closure for a container has a metal body shell (30) into which a plastics moulding (44) is snap-engaged. The moulding provides a screw thread (52) for the closure; in addition, it extends below the body shell to provide a security ring (50) which is attached by rupturable bridges (62). Relative rotation of the moulding and body shell when the closure is being fitted onto a container is prevented by teeth (58) formed around the top edge of the moulding, which deeply indents the sealing gasket (38) of the body shell.

Abstract: A piston for a pressure-dispensing container such as a cartridge for an extrusion gun has its closure panel formed of a central portion (34) arranged to receive the applied extrusion forces, and an annular and frustoconical outer portion (40) arranged to transmit the extrusion forces to the piston skirt (30) with an outwardly directed component by which the skirt is radially expanded to make firm sealing engagement with the container bore. The central portion is rigid so as to withstand the extrusion forces without any substantial distortion; the outer portion acts as a substantially rigid annular strut, notches (44) localizing any bending movements to the junctions of the outer portion with the central portion and with the skirt.

Abstract: A plastics strap handle is secured to a plastics container body by means of a spigot which is pushed into the wall of the container body to form a socket. Material from the wall around the socket is coined into an annulus surrounding the shank of the spigot to retain the head of the spigot in the socket.

Abstract: A plug lid for fitting in an aperture in a container comprises a peripheral flange, a plug wall extending from the inner periphery of the flange, a retaining bead protruding laterally from the plug wall at a distance from the flange, an annular portion extending inwardly from the plug wall, a frustoconical portion extending axially and inwardly from the inner periphery of the annular portion to support a central panel in or near the plane of the peripheral flange. The annular portion joins the inside of the plug wall adjacent the retaining bead and extends inwardly and axially at an obtuse angle A.degree. to the plug wall to join the frustoconical portion. The lids may be moulded from polyethylene, polypropylene or nylon.

Abstract: An end component 3 is spin-welded into the cut end of an extruded tube 1 with the application of axial pressure but without the application of radial pressure to the weld area. The radial forces required to create a weld are provided by hoop stresses which are formed in the tube by shock-cooling the tube as it emerges from the extrusion die. When the tube is cut, the hoop stresses cause the cut end of the tube to contract radially prior to insertion of the end component. To assist in insertion of the end component, a cylindrical skirt thereof 4 is provided with a chamfered end 9.

Abstract: During spin-welding of an end ring to a container body, the weld area is subjected to a radial pressure by means of a wire cable tourniquet under the action of a pneumatic cylinder. The interference fit between the ring and body is measured by reference to the torque required for their slow speed relative rotation or to the axial force required for their assembly and, according to the measured interference fit, the radial pressure applied by the tourniquet during welding is controlled.

Abstract: An end component for a spin welded container comprises a plug which is received within the container side wall for spin-welding thereto. An annular bead co-operates with a step on the wall to locate the plug. During welding, flash generated at the main weld area below the bead is prevented from escaping upwardly by the bead. A cavity is provided above the bead to retain any material which passes the bead or is formed by melting of the bead.