Abstract: A clamp for securing at least one cable to a support comprises a channel member having an apertured base and limbs shaped at their free ends for engagement with the support, and a sub-assembly comprising a screw a saddle captive on the end of the screw remote from the screw head and positioned inside the channel member, and a nut threaded on the shank of the screw between the screw head and the saddle, the aperture in the base of the channel being large enough to permit passage of the head of the screw but not so large as to permit passage of the nut.

Abstract: An optical cable comprises at least one optical bundle and at least two separate elongate reinforcing members. The axes of the or each optical bundle and the reinforcing members lie substantially in a common plane with the or each optical bundle located between and spaced from two reinforcing members. Each reinforcing member has an overall dimension perpendicular to said common plane that is substantially greater than the corresponding overall dimension of the or each optical bundle so that the or each bundle lies in the space bounded by two planes one located on each side of the two members and touching both members. An extruded outer sheath surrounds and fills the interstices between the optical bundle or bundles and the reinforcing members.

Abstract: In a modified "Conform" machine for continuous friction-actuated extrusion of metals, especially particulate copper, the abutment at the outlet end of the working passageway does not fully block the end of the wheel groove. Instead a substantial clearance is left, and metal extruding through it adheres to the wheel to re-enter the working passageway at the entry end. Preferably the abutment is of semicircular cross-section. For a given output rate, a significant reduction in torque, and working stresses, is obtained.

Abstract: A device for securing at least one cable to a support (not shown) and/or for securing together two or more cables comprising a base member having two inclined surfaces on which one or two of the cables can rest; a bar which is spaced from the base member between the inclined surfaces and extends lengthwise of the cable or cables and which is secured to the base member; a strap which can be passed around the bar and the cable or cables at least once; and tensioning means which can tension the strap when positioned around the bar and the cable or cables, to secure the cable or cables together and/or to secure the cable or cables to the base member.

Abstract: An overhead electric conductor with optical fibres loosely housed in the bore of a central core, which bore also contains a greasy water-impermeable medium 4, is manufactured by causing a preformed elongate metal member of U-shaped transverse cross-section and the optical fibres to advance in the direction of their lengths, the rate of advance of the fibres being restrained. As the U-shaped elongate member is transversely folded around the optical fibres greasy water-impermeable medium is injected into the bore of the elongate metal member under a controlled pressure. The consistency of the greasy water-impermeable medium the pressure and rate at which it is injected into the bore and the degree of restraint imparted to the optical fibres 3 is such that, in a predetermined length of the conductor, the length of the optical fibres exceeds the length of the bore by a controlled extent, preferably 1 to 3%.

Abstract: A composition of high oxygen index that yields little visible smoke and little or no corrosive fume on combustion and having adequate mechanical and electrical properties for cable jackets and bedding comprises;20-35 parts of ethylene-vinyl acetate copolymer;52-75 parts of an alumina trihydrate with at least half its weight in particles with a diameter in the range 0.5-3.0 micrometer;up to 3 parts of stearic acid or a stearate; andat least one antioxidant and if desired at least one curing agent in effective amounts not exceeding 4 parts in all.A double-layer of aromatic polyimide tape, the first layer helically lapped and the second preferably longitudinally applied, is interposed between a bedding an a jacket both of the above composition to give a superior low-smoke cable for use in tunnels of railroads or other transportation systems.

Abstract: A method of fitting an electrical connector housing to an electrical contact comprises feeding a chain of connector housings linked end to end in the direction of their length towards a fitting station and, at said fitting station, effecting relative lengthwise movement between the leading housing of the chain and a contact in such a direction as to cause the leading housing to be fitted on to the contact.

Abstract: A flexible stranded body, such as an electric conductor of an overhead electric transmission or distribution system, comprises at least one stranded layer of elongate elements of metal or metal alloy, at least one elongate compartment within and extending throughout the length of the stranded body and, loosely housed in the elongate compartment, at least one separate optical fibre and/or at least one optical bundle. Preferably, the elongate compartment extends within a circumferentially rigid central core which is surrounded by the stranded layer or layers but it may be a bore in an elongate element of a stranded layer or an elongate space bounded by two adjacent elongate elements.

Abstract: A method of shaping metal in the form of a parallel-sided elongate sheet to make from it a formed profile that is of uniform cross-section except that at least one longitudinal edge is worked to generate a repeating pattern along its length, comprising cold working the metal sheet successively (a) by rolling to increase the width of the sheet, (b) with one or more than one knurling wheel that generates the repeating pattern in the longitudinal edge or edges of the metal sheet and at the same time reduces the width of the metal sheet to substantially its original value, and (c) by roll-forming (b) to the said profile, which may for example be a channel of substantially U-shaped cross-section.

Abstract: Waterproof filling medium, used in telecommunication cables with cellular insulation of polyethylene or polypropylene, is based on a mineral oil (with or without a gelling agent such as microcrystalline wax) and includes two non-polar additives. The first is soluble and of low enough molecular weight to reduce significantly the osmotic pressure of the base, but does not diffuse into the insulation below 80.degree. C.; and the second is polymeric and of high enough molecular weight to increase the resistance to flow to obtain the required non-draining property. Filling of cells in the insulation is inhibited.

Abstract: A joint between two optical fibres comprises two cylindrical rods positioned with their longitudinal axes substantially parallel on a support device of such a form that the cylindrical rods are constrained to lie in tangential contact with one another to define between them an interstitial space, the two rods and the support device forming a sub-assembly; two optical fibres aligned in the interstitial space defined by the two rods so that the end faces of the optical fibres substantially abut; an elongate holding member positioned over the ends of the optical fibres aligned in the interstitial space to cover the interstitial space over at least a part of its length; and over the elongate holding member there is applied at least one resilient spring clip which so engages the sub-assembly that the elongate holding member is urged towards the two rods to secure the optical fibres with their end faces substantially abutting in the interstitital space between the two rods.

Abstract: In lightweight fabricated equipment of an overhead electric traction system, (e.g. section insulators and neutral sections), comprising at least one tension insulator mechanically connected between and electrically insulating from one another two elongate metal members, in at least one mechanical connection between the tension insulator and elongate metal member, an insulating end part of the tension insulator and an end part of the elongate metal member overlap and are interconnected by separate securing bolts. The undersurfaces of the end parts of the tension insulator and elongate metal member constitute a smooth running surface.

Abstract: Risk that metal particles carried by flowing oil in an oil-filled cable joint or termination will settle along an oil path between a cable conductor and the space bounded by the joint or termination enclosure is substantially reduced by making at least part, and preferably the whole, of the boundary wall of the path of a fibrous insulating material, e.g., paper, and by providing, at at least one end of the path, for filtering from flowing oil particles of metal and other undesirable materials that may be carried by the oil, filtering means comprising, in combination, electrically insulating filtering material and a fine metallic mesh, serving as an electrical screen. Fibres of the boundary wall so formed protrude into the path and restrict mobility of metal particles carried by the flowing oil; some metal particles will penetrate the fibrous insulating material which will also absorb from the oil some types of dissolved contamination, e.g., moisture.

Abstract: The outer conductor of a high frequency electric cable of the kind employed as a stationary elongate element for transmitting high frequency signals to, or receiving high frequency signals from a receiving or transmitting device carried by a mobile body, has extending along its length at least one row of mutually spaced apertures, the mutual spacing between adjacent apertures of the or each row decreasing along the length of the row, being a maximum value at one end of the row and a minimum value at the other end of the row. The or each row of apertures may be sub-divided into a plurality of sub-groups of apertures, the mutual spacing between adjacent apertures of each sub-group being constant, and the mutual spacing between adjacent sub-groups decreasing along the length of the cable.

Abstract: An electric busbar installation comprises at least one busbar comprising a rigid bare elongate conductor housed within and rigidly secured to and spaced from a rigid tube, arranged with its axis substantially vertical by longitudinally spaced rigid insulators, the space between the busbar and the tube containing an electrically insulating fluid which is in direct contact with the bare conductor of the busbar, at least one duct which is in thermal association with the bare conductor throughout the length of the busbar and which forms part of a closed circulatory system for evaporable refrigerant; and interconnected in the circulatory system, condensing means for receiving evaporated refrigerant from, and for delivering liquid refrigerant to, the duct.

Abstract: A conduit end is sealed around one or more than one insulated conductor by using a chamber (4) having a peripheral wall, a base with an opening through it communicating with the conduit (2) and an opening opposite the base. The conductor(s) (3) extend through both openings; a pre-formed annular body of a setting resin composition (8) is inserted while in a pasty or viscous condition into the chamber to encircle the conductor or conductors. Axial pressure is then applied to the still pasty or viscous annular body to cause it to flow and form a sealing body in peripherally continuous contact with the chamber and with the, or each, insulated conductor, after which the resin composition sets. A kit for use in the method is also claimed.

Abstract: In electrical terminal crimping apparatus comprising two crimping dies so mounted that one die is constrained to move towards and away from the other die, a wheel having circumferentially spaced, outwardly extending vanes is rotatably mounted with respect to the dies and a pawl, operatively connected to the movable die, is adapted to engage a ratchet, carried by the wheel, to effect partial rotation of the wheel. After a terminal has been crimped to an electrical lead and as the movable die moves away from the fixed die, the pawl automatically engages the ratchet and causes the wheel to rotate so that a vane pushes the terminated lead laterally from between the dies to a sufficient extent to permit the stripped end of another lead to be positioned between the dies.

Abstract: An extrusion machine is disclosed wherein wax or other suitable lubricant is applied to the side of the feedstock contacting the shoe of the extruder. A stick of wax may be supported in a cylinder having an open end facing the feedstock; the stick is a loose sliding fit in the cylinder and compressed gas introduced into the cylinder applies a substantially constant biassing force urging the stick into engagement with the feedstock and at the same time, by leaking between the stick of lubricant and the cylinder, cools the stick of lubricant to inhibit melting.

Abstract: In an oil-filled electric power cable installation, the oil is pressurized using oil tanks connected to stop joints in the usual way, and an oil-purifying unit is connected between stop joint and tank. The oil-purifying unit comprises a column or bed of a molecular sieve or other active purifying agent with particle sizes, and interstice sizes, big enough to limit the pressure drop across the unit to 20 kN/m.sup.2 at the most. This eliminates the need to provide bypass passages controlled by valves as the oil can flow both ways through the column.

Abstract: A flexible stranded body, such as an electric conductor of an overhead electric transmission or distribution system, comprises at least one stranded layer of elongate elements of metal or metal alloy, at least one elongate compartment within and extending throughout the length of the stranded body and, loosely housed in the elongate compartment, at least one separate optical fibre and/or at least one optical bundle. Preferably, the elongate compartment extends within a circumferentially rigid central core which is surrounded by the stranded layer or layers but it may be a bore in an elongate element of a stranded layer or an elongate space bounded by two adjacent elongate elements.