Abstract: A hydraulic wire joining device for connecting at least two wires. The device includes a hydraulic cylinder for clamping a wedge or spacer over at least two wires, and a work fixture for transmitting an cylinder force to the wedge. The cylinder is a two-stage type of cylinder, which has first and second coaxial cylinders and respective first and second coaxial pistons respectively forming the first and second chambers and third and fourth chambers. The first piston has passage means which has a pressure valve and which connects the first and third chambers upon opening of the pressure valve only at a second stage higher fluid pressure level, whereby a two-stage two-level force can be applied to the wedge for initial crimping and final crimping of the wedge.

Abstract: A joint structure for covering a joint between cables is provided in which an insulation structure extends over and beyond cut back ends of insulation layers of the cables, but terminates at a distance ahead of cut back ends of insulation shield layers of the cables. The insulation structure of the joint structure includes a multi-layered, heat shrinkable tube with its ends beveled or "feathered". In assembling the joint, the tube is positioned to overlie the cable conductors and the insulation layers of the cables and is shrunk thereover so as to terminate at a distance from the cut back ends of the insulation shield layers of the cables. The heat shrinkable tube can be manufactured with feathered edges, so that no additional time or labor is required to shape the sleeve when the joint is assembled. The joint structure also includes a semiconductive conductor shield member applied in successive convoluted layers over the exposed conductors of the joint prior to application of the heat shrunk tube.