Abstract: Method of welding two hollow ceramic half-components containing an organic binder whereby each half-component is first loaded into a die, the jointing planes of the two half-components are then brought into contact by bringing together the two dies, working pressure is thereafter applied to one of the half-components in a direction perpendicular to the jointing planes and vibration is simultaneously applied to the other half-component in a direction parallel to the jointing planes to effect the welding of the two half-components by interpenetration. The two dies are then separated and the joined monobloc component is removed and sintered without altering the component's monolithic quality.

Abstract: A composite type stay insulator comprises a central mandrel (4) made of insulating foam and having its ends (5) glued at (6) to two metal end pieces (1). The glue may be optionally conductive or semiconductive. A skein winding (8) of insulating resin-impregnated fibers is made around the end piece and mandrel assembly to transmit traction forces from a shoulder (7) on one of the end pieces to a corresponding shoulder on the other. The winding is then covered with a resilient insulating covering (9) which is optionally fitted with fins.

Abstract: An insulator core including a rod (20) fitted with a sheath (12) and with insulating fins (2,3) is fixed in a metal cap (10,10') by embedding the end (1) of the rod (20) in an organic embedding substance (9) in a thimble (5,5'), which has undercut zones and a flange (7) which is bonded or crimped to the sheath in a sealed manner, and embedding the thimble (5,5') in the cap (10,10') using a cheap inorganic cement (11). The thimble is coated with an anti-adhesive layer (27) which does not adhere to the embedding cement.

Abstract: A metal-capped electrical insulator and method of making same by forming a metal cap on an insulator dielectric by directly casting molten metal round a portion of the dielectric to embed it therein. Before casting the metal (16 or 17), a metal washer (1 ) is placed in contact with the boundary on the insulator at the edge of the portion to be embedded. The washer has a circular groove (2) open on the side through which the molten metal is poured. Before casting, said washer is deformed, by pressing it hard in a metal-casting mould (30) to the dielectric and deflecting the walls (3, 4) of the groove (2) to create an undercut in the metal washer.

Abstract: A method of manufacturing a sintered silicon carbide ceramic part in which is formed a mixture of carbide powder with a sintering additive based on boron, beryllium or aluminium, and an injection moulding additive comprising a mixture of polystyrene and a wax. A moulded part is manufactured by injection moulding and is then baked and is finally sintered.Polystyrene is used simultaneously as a moulding agent and as a carbonizable substance. When the moulded part is baked it is heated in air to a temperature between 230.degree. C. and 330.degree. C. and is then kept at that temperature for a fairly long time to remove the wax and to reticulate and oxidize the polystyrene.Application to manufacturing dense sintered parts.

Abstract: An insulating spacer subjected to bending stresses is formed from a glass fiber reinforced rod having a transverse hollow in the vicinity of at least one end. The rod is covered with a sealing elastomeric sheath. A lightweight cable clamping structure includes two half sleeves clamped around the one end by U-bolts. At least one of the U-bolts also presses a cable clamp toward one of the half sleeves. The one half-sleeve has an internal boss, shaped to fit the transverse hollow so as to fix the half-sleeves on the rod, and a transverse external groove facing the cable clamp to fix a cable against the sleeve.

Abstract: An electric insulator which includes a rod (2) made of glass fibres and resin, one end of said rod being received in a fitting (1) made fast to a post (20). To improve the mechanical strength of the rod (2) in the anchoring means, a fitting (1) with a double cone recess is provided and the end of the rod has one or two grooves machined therein and is embedded in the recess in an organic substance (16). The grooves are formed only through the lower portion of the rod where the fibres are subjected to compression forces.

Abstract: An insulator core made of an organic substance and including a central rod (1) fitted with an insulating covering (4) is fixed in a metal cap (8) which is not machined.The end of the rod has undercut zones such as circumferential channels (10) or double cones (9), and a ductile metal cup (5) whose edges are made integral with the insulating covering (4) in a sealed manner is crimped on the rod. The cup (5) is itself embedded in the cap (8) by means of an organic cement or embedding substance (7) which is reinforced.

Abstract: The invention relates to an electric insulator of the line post type which has a rod (2) made of glass fibres agglomerated in resin and covered with a protective elastomer sheath. A socket (15) with an opening (16) is provided to make it fast with post (14). The socket end of the rod is machined to provide a hollow (8) designed to improve the mechanical characteristics of the rod in the fitting (1) of the post (14). A locking piece (17), which is complementary to the hollow (8) in the rod (2), clamps the assembly together by means of two fixing parts (18).

Abstract: A silicon nitride material is obtained by natural sintering in the presence of a small quantity of yttrium oxide. The method comprises the steps of mixing silicon powder with relatively small quantities of aluminum powder and yttrium oxide powder, nitriding the mixture of powders, re-crushing the nitrided mixture of powders, shaping the re-crushed powders, and then sintering the shaped re-crushed powders.

Abstract: The binding is disposed substantially symmetrically about a plane of symmetry which passes through the insulator (1) and which is orthogonal to said conductor (5). It comprises a ring (10), two conductor-retaining branches (11, 6), and tightening means (21, 22) for tightening the binding. Each of said branches comprises a first end portion (8, 9) in the form of a preformed spiral retainer for wrapping around said conductor, an intermediate portion (6) in the form of an arc of a circle having a radius of curvature that is substantially equal to the radius of the bottom of said circumferential groove, and a second end portion providing an eye for engaging the tightening means. Both branches pass through the ring at the transition between their spiral end portions and their intermediate arcuate portions. At least one elastomer block (20) is inserted between said eyes to be held in position by said tightening means drawing said eyes towards each other.

Abstract: The binding is disposed substantially symmetrically about a plane of symmetry which passes through the insulator and which is orthogonal to said conductor (10). It comprises a first ring (8) for occupying a portion of the circumferential groove, a second ring (9) for occupying the top groove, two conductor-retaining branches (5), and tightening means (2, 11) for tightening the binding. Each of said branches comprises a first end portion (7) in the form of a preformed spiral retainer for wrapping around said conductor, an intermediate portion for threading through said second ring when lodged in the top groove and through said first ring when lodged in the circumferential groove, and then extending in an arc of the same diameter as the circumferential groove to a second end portion which provides an eye (6) for engaging the tightening means.

Abstract: A tool having two side rods spaced apart by a connecting crossbar facilitates clamping and unclamping a cable in a groove on an insulator cap. To clamp the cable, the crossbar is inserted into a first recess on the cap between the groove and a protruding stud, and the side rods are pressed against a front branch of a clamp wire pivotally mounted on the cap to snap the front branch into a second recess below a front guide surface on the stud. To unclamp the cable, hooked extensions of the side bars engage the front branch of the clamp wire and lift it out of the second recess when the crossbar is pressed against the front guide surface of the stud. Separate clamping and unclamping tools can be mounted on an insulating handle for pivoting between a rest position and an operating position and spring biassing means can be provided to urge each tool toward a rest position.

Abstract: An insulator comprising a plurality of fins (1) or one-piece groups of fins made of elastomer and having sleeves (2) disposed end-to-end. The fins surround a central member (3) and are vulcanized. The fins form a water-tight tube whose cohesion is ensured at least by vulcanizing intermediate elastomer portions (5) which are inserted raw between vulcanized fins or one-piece groups of fins and adhere to the facing surfaces of the said sleeves by virtue of their subsequent vulcanization.

Abstract: A bending resistant structure includes a rod (1) which is sealed in a casing (6), said casing receiving a double frusto-conical shaped wedging member (2,3,4) which applies jamming stresses to the rod. The wedging member is formed by a resin mass (2) moulded on the end of the rod (1), a resilient cap (3) covering the resin mass (2), and a thin metal sheathing (4) shrink-fitted over the cap (3), said wedging member being sealed in an associated casing (6), the structure being particularly resistant to high bending moments. Application to electric insulators and more particularly to those of the line-post type.

Abstract: An insulator which includes at least one plate-shaped dielectric component 3 having a cylindrical head 4, at least one connecting member 14 having at least one pin end 5 embedded inside a recess defined within the head of a dielectric component and at least one other connecting member having a cap 12 which covers the head of the dielectric and is sealed thereon, the one connecting member having a flange (15, 27, 28, 29) spaced from the embedded pin end and whose outer diameter is larger than the outer diameter of the head in which said end is embedded and the cap of the other connecting member having a flared base (16, 30, 31, 32) which covers an annular portion of the dielectric which extends beyond the outer diameter of the head, so as to define a rigid extension on either side of the dielectric component.The invention applies in particular to multiple-dielectric insulators in which the dielectric components are made of tempered glass.

Abstract: The invention relates to fixing a bare cable on an electric insulator by means of a device which includes a fixed part integral with the insulator and which has a groove (5) which forms a cradle in which the cable is laid, as well as a moving part (8) which holds the cable in its cradle in the locked position. According to the invention the fixed part and the moving part have contact surfaces with the cable to be fixed such that said cable in the locked position is subjected to progressive deformation of its cross-section in a first direction substantially perpendicular to the direction which corresponds to the clamping of the moving part at the central portion of the cradle and in a second direction substantially perpendicular to the first direction at the two ends of the cradle. Application in particular to support insulators and to suspension insulators.

Abstract: Electrical insulator comprising an ouer tube of dielectric material filled with blocks of dielectric foam and sealed at its ends.The filling is manufactured independently of the tube in a material of substantially compatible coefficient of thermal expansion. The filling is connected to the inner surface of the tube by an adhesive interface material which provides good mechanical and electrical connection between the tube and its filling.Application to electrical insulators which are of large diameter and/or great length.