Abstract: A flameproof electrical insulating fluid and an electrical cable impregnated with such fluid, the insulating fluid being a mixture of a polymethylsiloxane having a viscosity greater than 5 centistokes at 25.degree. C. and an aromatic compound corresponding to the chemical formula: ##STR1## where R is an aliphatic radical and said aromatic compound is present in the mixture in an amount from 0.5% to 10% by weight of the total weight of the mixture. Preferably, the aromatic compound is isopropyldiphenyl.
Abstract: A coating composition comprising (A) a thermoplastic resin having a glass transition temperature of 0.degree. to 80.degree. C., (B) a compound having 2 or more hydroxyl groups in the molecule, (C) a thixotropic agent and (D) a solvent, and said coating composition having a viscosity of 3 to 50 poises at 25.degree. C. and a thixotropy of 2 or more can give a moistureproof insulating coating film with uniform and large thickness and very few bubbles by one-time treatment over packing circuit boards.
Type:
Grant
Filed:
February 28, 1983
Date of Patent:
December 25, 1984
Assignees:
Hitachi Chemical Co., Ltd., Hitachi, Ltd.
Abstract: A method and composition for effecting splices of high voltage cable sections for use with a mold placed around the cable sections. The composition comprises a liquid polyolefin, a finely divided solid polyolefin and a chain extension agent capable of reacting to form addition polymer linkages with the liquid polyolefin.
Abstract: An electrical insulating oil composition which is characterized in that said insulating oil composition contains 5 to 300 ppm (as sulfur) of sulfur compounds and exerts excellent deterioration resistance when the insulating oil composition is fed through or used in contact with a substance made of lead or a lead alloy.
Abstract: Disclosed is an apparatus which is resistant to electrical breakdown consisting of a chamber containing electrodes separated by dielectric gas supersaturated with the vapor from a dielectric liquid.
Abstract: A liquid halogenated hydrogenated hydrocarbon composition suitable for use as a dielectric and/or arc-extinguishing fluid in electrical apparatus, which comprises(a) a major proportion by weight of one or more halogenated paraffinic hydrocarbons having at least 8 carbon atoms and containing from 40% to 70% by weight of halogn based on the halogenated paraffinic hydrocarbon, and(b) a minor proportion by weight of at least one non-flammable viscosity-reducing additive for the halogenated paraffinic hydrocarbon (a) which contains at least 50% by weight of halogen based on the additive and is a halogenated aliphatic hydrocarbon containing from 2 to 6 carbon atoms.Suitable electrical apparatus may comprise a circuit interruption device such as a switchgear.
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: An electrical insulating oil and oil-filled electrical appliances, in which the insulating oil comprises a mixture of diarylalkanes and alkyl-3-arylindane derivatives and/or 1,3-diarylbutene derivatives, and has various advantageous properties such as a high dielectric constant, hydrogen gas absorbing capacity, and adaptability to plastic film materials. By impregnating with the above insulating oil, high performance and long life electrical appliances can be manufactured.
Abstract: The electric device according to the present invention has as its constituents the insulating materials and elements comprising films of synthetic resin, for instance, polypropylene, impregnated with 1-phenyl-2-ethylphenylethane and/or 1-phenyl-2-isopropylphenylethane.According to the present invention, insulating oils having favorable compatibility with the film of synthetic resin such as polypropylene and favorable affinity to metals and having low viscosity have been provided, and in addition, electric devices excellent in properties of withstanding a high voltage and dielectric properties in a broad range of temperature from a low temperature to a high temperature have also been offered.
Type:
Grant
Filed:
October 29, 1980
Date of Patent:
May 18, 1982
Assignees:
Kureha Kagaku Kogyo Kabushiki Kaisha, Nissin Electric Co., Ltd.
Abstract: A dielectric fluid composition with high electrical strength characterized by a gas mixed with the vapor from a first fluid having a high vapor pressure at a low temperature and the vapor from a second fluid having a low vapor pressure at a low temperature to effect a mixture having a higher electrical strength than any component thereof over a temperature range from about -20.degree. C. to -40.degree. C. to about +120.degree. C. to +140.degree. C., with the vapor pressure of the mixture at the highest temperature being about one to two atmospheres. Also, the mixing of low and high cost liquids to obtain a low cost liquid with a vapor with an electrical strength equivalent or better than the best vapor over a wide temperature range.
Abstract: This specification relates to a communication cable and method of making it, particularly where the cable includes a high pair count with small conductors so that the filling compound can be made to permeate to the center of the cable without having the filling compound become too viscous to reach the center of the cable when filled by the liquid filling process. The filling compound does not drip at temperatures up to 90.degree. C. From five to ten parts by weight are used of a polyethylene compound as one ingredient of the filler material. The major ingredient of the filler is a paraffinic oil which constitutes 100 parts of the filler compound. Other important considerations are to formulate the compound so that it will not permeate into the cells of the foam skin or all foam insulation.
Abstract: A dielectric fluid composition with high electrical strength characterized by a first fluid selected from the group consisting of electronegative gases, such as SF.sub.6, CCl.sub.2 F.sub.2, C.sub.2 F.sub.6, CF.sub.3 Cl, and CF.sub.4, and mixtures thereof; or from another group consisting of electropositive gases, such as N.sub.2 and CO.sub.2, and mixtures thereof; or from mixtures of the two groups; and a second fluid from a group of atomized liquids, which may be chlorinated liquid, such as, C.sub.2 Cl.sub.4 (tetrachloroethylene); and fluorocarbon liquids, such as, C.sub.8 F.sub.16 O (perfluorodibutyl ether), and mixtures thereof.
Type:
Grant
Filed:
June 27, 1980
Date of Patent:
October 20, 1981
Assignee:
Electric Power Research Institute, Inc.
Inventors:
Ronald T. Harrold, Lawrence E. Ottenberg
Abstract: Liquid, non-flammable dielectric compositions especially adapted as insulators/coolants for transformers and the like, are comprised of an admixture of [i] a bromochlorobenzene and [ii] a polychlorobenzene, and, optionally, [iii] a diluent therefor.