Abstract: An electrical insulator including a tube surrounded by an insulating sheath. The insulating sheath is composed of a filled, hardened, flexibilized, hydrophobic, cycloaliphatic epoxy resin containing from 25 to 75 percent by weight of mineral filler. The process for manufacturing this insulator includes the steps of installing the insulator tube or a precursor of the tube in an electrical insulator mold, feeding the filled unhardened hydrophobic cycloaliphatic epoxy resin in the mold so as to form the sheath, hardening the resin inserted in the mold so as to obtain the insulator, and extracting the insulator obtained from the mold.

Abstract: The gas-tight, high or medium voltage electric switch device (1), containing an insulating gas under pressure, comprises switch contacts (2) capable of occupying an open position and a closed position and disposed inside a composite insulator formed by a rigid tube (3) surrounded by an elastomer casing (4) whose outside surface defines a succession of annular fins. The rigid tube and the elastomer casing are arranged so as to define an observation window (7) that is at least translucent, and through which the open or closed position of the switch contacts is visible.

Abstract: The invention relates to a high-performance dielectric oil comprising approximately 75 to 95% by volume of a naphthenic oil and approximately 5 to 25% by volume of an ester oil, in particular a synthetic ester oil and more preferably an oil of the family of polyolesters. The high-performance dielectric oil may be used in high-voltage electrical equipment such as power, measurement, distribution or traction transformers, tap changers, bushings, distributors, oil-immersed circuit breakers, power capacitors, cables, etc.

Abstract: Supports for high or medium voltage electrical conductors (6, 7) at potentials different from the potential of an enclosure (1) are supported by disc-shaped parts (4, 5) made from thermoplastic polyester, for example terephthalate polyethylene. The discs (4 and 5) provide good insulation without largely disturbing the electrical field around the conductors due to their fairly low dielectric constant. They are also compatible with use under SF6 gas.

Abstract: This electrical switchgear has an interrupting chamber enclosing an interrupting gas (G) substantially devoid of SF6 and of CF4, and a first arcing contact (10) and a second arcing contact (18), the two arcing contacts moving causes an electric arc (26) to strike, while at least one irradiation wall (22) is provided that is suitable for being reached by the electric arc. At least two component materials that are part of at least one element selected from the interrupting gas, the first and second arcing contacts, and the or each irradiation wall, are suitable for decomposing under the effect of the electric arc, so as to form decomposed species (e1, e2) suitable for combining in the interrupting chamber, in order to form at least one new gaseous species (G1), before the electric arc is extinguished, the dielectric properties of said at least one new gaseous species being superior to the dielectric properties of said interrupting gas (G).

Abstract: An electrical contact member, suitable for electrically interconnecting two conductive members in series, which members can move relative to each other and are part of an electrical apparatus. The electrical contact includes a strength-imparting base layer made of an electrically conductive material, and a coating layer formed from metallic silver and configured to come into contact with the two electrically conductive members. The coating layer has a micro-structure formed by pure silver crystals, with a presence of nodules made of silver and of an additional metallic material formed by at least one additional metal that is different from silver.

Abstract: This electrical switchgear has an interrupting chamber enclosing an interrupting gas (G) substantially devoid of SF6 and of CF4, and a first arcing contact (10) and a second arcing contact (18), the two arcing contacts moving causes an electric arc (26) to strike, while at least one irradiation wall (22) is provided that is suitable for being reached by the electric arc. At least two component materials that are part of at least one element selected from the interrupting gas, the first and second arcing contacts, and the or each irradiation wall, are suitable for decomposing under the effect of the electric arc, so as to form decomposed species (e1, e2) suitable for combining in the interrupting chamber, in order to form at least one new gaseous species (G1), before the electric arc is extinguished, the dielectric properties of said at least one new gaseous species being superior to the dielectric properties of said interrupting gas (G).

Abstract: The present invention relates to an electrical insulator (1) comprising a tube (3) surrounded by an insulating sheath (5) that may be smooth or provided with fins (7). The insulating sheath is composed of a filled, hardened, flexibilised, hydrophobic, cycloaliphatic epoxy resin containing from 25 to 75% by weight of mineral filler. The process for manufacturing this insulator comprises the steps consisting of installing the insulator tube or a precursor of the tube, in an electrical insulator mould possibly provided with fins, feeding the filled unhardened hydrophobic cycloaliphatic epoxy resin in the mould so as to form the sheath and the fins of the insulator around the said tube or its precursor, hardening the resin inserted in the mould so as to obtain the insulator, and extracting the insulator obtained from the mould. The electrical insulator according to the invention can be used in a high voltage application.

Abstract: Supports for high or medium voltage electrical conductors (6, 7) at potentials different from the potential of an enclosure (1) are supported by disc-shaped parts (4, 5) made from thermoplastic polyester, for example terephthalate polyethylene. The discs (4 and 5) provide good insulation without largely disturbing the electrical field around the conductors due to their fairly low dielectric constant. They are also compatible with use under SF6 gas.

Abstract: The gas-tight, high or medium voltage electric switch device (1), containing an insulating gas under pressure, comprises switch contacts (2) capable of occupying an open position and a closed position and disposed inside a composite insulator formed by a rigid tube (3) surrounded by an elastomer casing (4) whose outside surface defines a succession of annular fins. The rigid tube and the elastomer casing are arranged so as to define an observation window (7) that is at least translucent, and through which the open or closed position of the switch contacts is visible.

Abstract: The invention relates to a high-performance dielectric oil comprising approximately 75 to 95% by volume of a naphthenic oil and approximately 5 to 25% by volume of an ester oil, in particular a synthetic ester oil and more preferably an oil of the family of polyolesters. Applications: high-voltage electrical equipment, for example power, measurement, distribution or traction transformers, tap changers, bushings, distributors, oil-immersed circuit breakers, power capacitors, cables, etc.

Abstract: An electrical contact member, suitable for electrically interconnecting two conductive members in series, which members can move relative to each other and are part of an electrical apparatus. The electrical contact includes a strength-imparting base layer made of an electrically conductive material, and a coating layer formed from metallic silver and configured to come into contact with the two electrically conductive members. The coating layer has a micro-structure formed by pure silver crystals, with a presence of nodules made of silver and of an additional metallic material formed by at least one additional metal that is different from silver.

Abstract: The invention concerns an insulating nozzle for a gas blast circuit breaker. In accordance with the invention, the material constituting the nozzle comprises (A) 90% to 99.9% by weight of a fluorinated polymer, and (B) 0.1% to 10% by weight of a filler based on at least one oxide selected from (B1) SiO2 and other oxidized forms of metals from column IVA of the periodic table, and (B2) ZnO, CdO and other oxidized forms of metals from column IIB of the periodic table.

Abstract: This arcing contact element (10, 18) is capable of occupying an initial position in which it is in contact with another arcing contact element (18, 10), as well as a second position, in which it is separated from this other arcing contact element so as to allow interruption of the current. This element consists of carbon fibres embedded in a matrix which includes at least one electrically conducting material linked to graphite.

Abstract: The invention concerns an insulating nozzle for a gas blast circuit breaker. In accordance with the invention, the material constituting the nozzle comprises (A) 90% to 99.9% by weight of a fluorinated polymer, and (B) 0.1% to 10% by weight of a filler based on at least one oxide selected from (B1) SiO2 and other oxidized forms of metals from column IVA of the periodic table, and (B2) ZnO, CdO and other oxidized forms of metals from column IIB of the periodic table.

Abstract: An end fitting having a bore that forms a sleeve for the shank of an electrical insulator of composite structure. The bore has a substantially frustoconical wall that flares away from the bore opening towards the end wall of the bore and has an annular swelling directed towards the inside of the bore. This complex shape for the wall of the bore contributes to reinforcing the strength of the fixing between the end fitting and the shank by interference due to heat shrinking.