Abstract: Described herein are coupling means for joining substrates, for example, tubular articles, which include an inner member, having disposed thereon a fusible agent for binding the substrates together, and an outer member. The substrates to be joined are inserted between the fusible agent and outer member and the resulting assembly is heated. The application of heat is maintained until it permeates the assembly and raises the temperature of the fusible agent enough that it melts and flows through and/or about the substrates to be joined. The inner and outer members act to confine the melted fusible agent by defining boundaries between which it can flow. Longitudinal flow of the agent can be controlled by limiting the area heated, by the configuration of the coupling members or substrates, or by providing the coupling with additional members that "dam" longitudinal flow. When the heating is discontinued, the fusible agent hardens to bind the substrates together.

Abstract: In, or for use in, a vehicle inner tube splicing machine, a tube end cutting assembly comprising a cutting knife supporting carriage which is mounted on a pair of spaced parallel guide shafts and is reciprocated by hydraulically powered means. The knife supporting carriage also has mounted thereon scrap removal means which co-acts with cutting knives to remove off-cuts from said tube ends.

Abstract: A section of conduit is insulated by a thermoplastic outer pipe and an insulating layer of foamed or beaded insulating material disposed in the annular space between the outer pipe and the conduit. The annular layer is preformed to substantially the size of the annular space, then the outer pipe is heated to cause expansion of its diameter and facilitate insertion of the annular layer within the outer pipe. The inner pipe, or the conduit, may also be thermoplastic and may be cooled to cause contraction to facilitate insertion of the annular layer over it. After the outer pipe and inner pipe have returned to ambient temperature, the annular layer is retained within by a shrink fit, without chemical bonding between the annular layer and the pipes. Sections of the pipe are joined by simultaneously heating the ends of the inner pipe, annular layer, and outer pipe, placing the ends of one section against the ends of the other section, and allowing them to fuse while cooling.

Abstract: A method and apparatus for butt welding two surfaces of different polyethylenes by heating the two surfaces up to different temperatures at which the viscosities of the two different polyethylenes of the two surfaces are equal. The heating device for heating the polyethylene surfaces comprises two separate plates which can be heated up to different temperatures. The device is also provided with pressure regulating means for controlling the pressure at which the two surfaces are pressed onto each other.

Abstract: Plastic elements, such as conduit, and method and apparatus for joinder of same characterized by respective regions, or surfaces, of hot-to-cold plastic adjacent regions of hot-to-hot plastic for forming a substantially immediate physical fixation of the hot-to-cold regions and followed by a more nearly perfect sealing fusion of the hot-to-hot regions to form a strong sealing joint. In a specific embodiment, a tubular end is joined to a fitting in which the fitting has one or more annular recesses about its bore for allowing expanded, excess molten plastic to flow thereinto and become solidified for a strong sealed joint. This also eliminates forming streamers that frequently caused leaks in the joints heretofore. Also disclosed are the details of the apparatus for heating the respective regions, or surfaces, of the plastic elements.

Abstract: Apparatus for forming annular articles from elongated workpieces of thermoplastic material is provided with clamps for grasping the ends of the workpiece, and a heating plate with two opposed surfaces; the clamps apply the ends of the workpiece to the plate to heat them and then bring the ends together.