Abstract: Tracking is reduced in insulators comprising one or more polymers and an anti-tracking filler system comprising (a) a hydrate of alumina having a specific surface area of at least 2 m.sup.2 /g measured by the BET method, and (b) a compound selected from the group consisting of oxides, mixed oxides and mixtures of oxides wherein said compound contains at least one element selected from the group consisting of transition series elements, lanthanide series elements and nontransuranic actinide series elements.

Abstract: Provided is an electrical insulation body useful in electrical installations operated with SF.sub.6 as a quenching and/or insulating gas. The insulation body is comprised of a thermosetting resin matrix and a mineral filler of predominantly quartz powder and from about 5 to 50 percent by weight of the mineral filler of a second mineral powder component for increasing resistance to SF.sub.6 cleavage products, which second component comprises at least one alkaline earth metal carbonate.

Abstract: A particular dielectric fluid, having a composition with a specific gravity of at least 1.02 and consisting essentially of a silicone fluid and an additive, soluble in said silicone fluid, selected from the group consisting of trimethylsilyl treated (CH.sub.3).sub.3 SiO.sub.1/2 /SiO.sub.2 resin copolymer, dipropyleneglycoldibenzoate, dixylylethane, phenylxylylethane, and a mixture of [(CH.sub.3).sub.3 Si].sub.2 O treated silica and a silica aerogel, is employed to encapsulate and insulate an electrical cable splice. The same particular dielectric field composition is also used to fill an electrical cable's conductor interstices.

Abstract: Terminations and splices in high voltage electrical cable can be shielded by shrinking over the termination or splice a heat recoverable hollow article which comprises a heat-shrinkable outer sleeve whose outer surface is anti-tracking at voltages of 2.5 KV and at least part of whose inner surface has a layer thereon which is solid at room temperature and which has electrical stress-grading character.

Abstract: Tracking is reduced in insulators comprising one or more polymers and an anti-tracking filler system comprising (a) a hydrate of alumina having a specific surface area of at least 2 m.sup.2 /g measured by the BET method, and (b) a compound selected from the group consisting of oxides, mixed oxides and mixtures of oxides wherein said compound contains at least one element selected from the group consisting of transition series elements, lanthanide series elements and nontransuranic actinide series elements.

Abstract: The resistance of insulating pieces made of fiberglass reinforced plastics against the decay products of SF.sub.6, such as occur within sealed high-voltage switching devices is unexpectedly enhanced by the use of a reinforcing fiberglass made of a low-alkali silicate glass containing neither boron nor boron-compounds.

Abstract: An electrical insulation body formed of a polymer binder highly filled with electrically non-conductive inorganic inert filler particles, including in excess of 85% of such particles. Such high loading is facilitated by grading the particles in nonhomogeneous sizes including relatively large ones and by use of polymer binders of relatively low viscosity.

Abstract: An electrical apparatus, comprising an electrical conductor, is encapsulated with a cured, solid insulation comprising bonded, catalyzed, resin coated filler particles, where the resin constitutes from about 1 weight percent to about 12 weight percent of the resin coated filler particle weight.

Abstract: An arc track resistant, high voltage, filled synthetic resin insulator is disclosed which exhibits a wide range of desirable qualities heretofore unobtainable with any single type of prior insulator. The insulator hereof unexpectedly gives excellent arc track and flame resistance, along with a flexibilized yet rugged construction having good weatherability properties. These qualities are achieved through use of a relatively critical selection of components and proportions which also facilitate cast construction of the insulators by giving a pourable, yet highly filled liquid casting composition during the fabrication stage. The insulators include critical quantities of hydrated alumina (from about 60 to 75% by weight) and a synthetic resin matrix having expoxidized castor oil (18 to 24% by weight) and a glycidyl rigidizer therein, along with a curing agent and accelerator.

Abstract: New high voltage insulating compositions are disclosed. The compositions comprise a polymer (e.g. a polysiloxane, epoxide resin or a polymer of one or more olefins or substituted olefins), an antitracking additive (e.g. an alumina hydrate), and certain organic polymerizable phosphorus-containing compounds which have been found to provide the compositions with greatly improved resistance to erosion by high voltage stress. The phosphorus-containing compounds include phosphonates, phosphates, phosphites, phosphinates, phosphonites, phosphinites, phosphine oxides and sulfides, and phosphines, and salts and complexes thereof. The phosphorus-containing compound can react in situ with the polymer or other ingredients of the composition.

Abstract: An electrical insulating material having anti-tracking properties has incorporated therein an erosion inhibiting fluorine-substituted compound. The electrical insulating material comprises a polymeric material having an anti-tracking filler and the fluorine-substituted compound is a hydrophobic, non-ionic compound having a fluorine-substituted aliphatic carbon chain linked to a group having an affinity for the polymeric material and/or the anti-tracking filler. The electrical insulating material may be used in high voltage applications where it is necessary to resist erosion and/or control leakage currents.

Abstract: The invention relates to electrical insulators having increased resistance to partial discharges and electrical equipment comprising such electrical insulators.These electrical insulators are formed of a macromolecular material in which is incorporated a chelate which is a derivative of an organic compound of general formula: ##STR1## wherein: R is CH.sub.2 COOM or --OH,M is Na or H,x is an integer from 1 to 4,n is an integer from 0 to 4,the metal chelate being present in the material in an amount sufficient for promoting the extinction of partial discharges, said amount not exceeding a value which would alter the physical properties of the insulator such as the volume resistivity thereof.

Abstract: Carbon formation on voltage breakdown and sparking, and consequent carbon deposits on insulators and other surfaces, is suppressed in dielectric gases of halogenated alkanes by adding SF.sub.6 and/or CO.sub.2 to the halogenated alkane to form a gaseous dielectric mixture. Moreover, certain of the gaseous dielectric mixtures evidence unexpectedly high dielectric breakdown voltages. The gaseous dielectric mixtures are useful in high voltage coaxial lines, in transformers, in minisubstations, and the like.

Abstract: A filler system for polymers is disclosed which provides high voltage insulation which is resistant to tracking. The filler system utilizes a combination of alumina trihydrate and a chemically treated silica filler. The silica-treated filler results from the exposure of an inorganic silicon-containing filler having a specific surface area of at least 40 square meters per gram to one or more silanes. Preferred silanes are substituted silanes having the formula R.sub.n Si X.sub.4.sub.-n where n is 1, 2 or 3, R is an organic radical bonded to the silicon atom by a Si--C bond and X is a radical bound to the silicon atom via an atom other than a carbon atom.

Abstract: A weather-resistant high-voltage electrical insulator appliance, or at least a portion thereof which is exposed to the atmosphere, is formed of a solvent-free aliphatic polyurethane which is at least substantially free of aromatic groups.