Abstract: A method of forming a connection part for polyolefin insulated electrical wires or cables is disclosed which comprises a cross-linkable reinforcing insulation layer around said connection part, providing around said reinforcing insulation layer a heat shrinkable tube consisting of an integrated assembly of a semiconductive layer and a specific insulated portion consisting of at least two cylindrical heat shrinkable semiconductive members in combination with each other through an insulation material, and then heating said tube under pressure to effect crosslinking of said reinforcing insulation layer and cause said reinforcing layer to become integrated with said heat shrinkable tube. A heat shrinkable tube for use in this method is also described.

Abstract: A heat-shrinkable tube for use in forming a connection part for shielded polyolefin insulated electrical wires or cables. The heat-shrinkable tube comprises an integrated assembly of two cylindrical heat-shrinkable semiconductive members arranged end-to-end and surrounded and joined at the adjacent ends thereof by an insulation material. The shrink ratio of a narrow region of the heat-shrinkable tube defined by the adjacent ends and joining insulation material is smaller than that of the remainder of the tube. The adjacent ends of the cylindrical members may partially overlap each other, and a portion of each adjacent end may be folded back upon itself to produce a rounded shape for avoiding concentration of the electric field.

Abstract: A method of connecting two cables where a reinforcing insulation layer is formed over a connection part of the conductors of the cables. A heat-shrinkable tube is provided on the reinforcing insulation layer by heating the heat-shrinkable tube to form a cable connection part. The cable connection part is shaped by heating while being pressurized in a fluid medium.

Abstract: A fire spreading inhibitor composition comprising about 20 to about 40% by weight of an emulsion of a synthetic resin, about 1 to about 15% by weight of non-fusible organic fibers, about 20 to about 70% by weight of an inorganic powder at least about 50% of which is clay and/or zinc borate, and about 5 to 20% by weight of a halogenated hydrocarbon, all percentages being based on the dry weight as a coating.