Abstract: An elongated, insulative tube of high mechanical strength consists of resin bonded glass fibers wound in alternating helical and circumferential winding patterns. The glass fiber convolutions at the outer limits of these winding patterns embrace metallic inserts, securely captivating them within the open ends of the tube. Tapped central bores in these inserts threadedly receive end fittings adapting the tube to a transmission line supporting function. The tube also externally mounts a pair of spaced arcing rings and internally mounts a varistor array for protecting a transmission line against lightning strikes.

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: A process for continuous production of shaped bodies of synthetic resin reinforced with axially parallel fibers wherein a plurality of continuous fibers are drawn through spaced apertures in a perforated guide plate and then through an alternating series of impregnating baths and shaping nozzles and finally through a hardening zone. The impregnating baths, shaping nozzles, and drying zone are disposed in a vertical arrangement, the shaped body withdrawn from one shaping nozzle is passed with a further group of fibers through the next resin impregnating bath and shaping nozzle, the impregnating resin on the surface of the shaped body is still liquid as it enters the next impregnating bath and all of the impregnating baths and the drying zone are maintained at the same temperature. The resulting fiber-reinforced shaped synthetic resin bodies are particularly suitable as electrical insulators which also exhibit good mechanical strength and which are especially useful in high voltage installations.

Abstract: An elongated, insulative tube of high mechanical strength is equipped with fittings at each end for electrical connection with a high voltage transmission line and a grounded tower. An external spark gap is provided between a first arcing ring mounted in electrical connection with one end fitting and a second arcing ring mounted to the tube intermediate its ends and electrically connected with a contact member disposed within the tube. The portion of the tube interior between the contact member and the other end fitting is packed with a series array of varistor discs. The tube maintains the line in spaced relation with the tower, while the varistor array and spark gap absorb voltage surge differentials between the line and tower.

Abstract: An electrically nonconducting hollow-profile structural part having a protective cover, preferably made of polyester threads or fibers, with a mechanically supporting glass-reinforced plastic core, especially for SF.sub.6 insulating gas technology. The hollow-profile structural part has an end that is conically shaped and connected to an attaching element with an oppositely facing conical surface by means of conically-constructed screw and/or cemented connections in such a way that the glass-fiber interfaces of the core exposed at the end surface are covered gastight by the cone superficies of the attaching element. As a result, the SF.sub.6 insulation gas products of separation which attack glass and which develop as a result of corona discharges cannot come into contact with the glass fibers.

Abstract: A precision injection-molded form for an inductance coil comprises a cylindrical core member having a surface of relatively low dimensional precision, and a thin plastic layer molded over the surface to provide a surface of high dimensional precision for supporting the windings of the coil. Metal insert-members having threaded axial bores and radially extending wing portions are provided at either end of the core to establish electrical contact with the winding and a mounting capability for the assembly. The coil form is formed by injection molding techniques and apparatus which provide for axial compression of the assembly prior to molding to obtain a predetermined longitudinal dimension, and for equalization of forces exerted during molding to prevent longitudinal deformation.

Abstract: A high voltage insulator made up of a number of coaxially nested interlocking metal shell-like elements tapered from one end to the other, there being a layer of insulating material arranged between adjacent elements; the elements are each formed with corrugations that are uniformly spaced in the axial direction and have a radial extent greater that the thickness of the insulation, the externally convex portions of the corrugations increase in size from the smaller end to the larger and the externally concave portions correspondingly decrease in size; the thickness of the metal and the thickness of the insulation layer are substantially uniform where the elements overlap and the overlapping surfaces of each element are equi-distant at all places from the surface from any overlapped or overlapping element. The corrugations are annular or helical, in the latter case the elements being screwed together to constitute the insulator.

Abstract: An insulated runner for use in an overhead electric traction system comprises at least one elongate reinforcing body of high tensile strength made wholly or substantially of insulating material, for example a rod of resin bonded glass fiber, and provided with metal terminal fittings, and at least one body of abrasion-resistant ceramic or vitreous material which is associated with, and extends lengthwise between the terminal fittings of, the reinforcing body and which provides an effective running surface. The outermost surface of the insulated runner between its terminal fittings is of an insulating material that is resistant to tracking. The abrasion-resistant body may enclose fully the part of the reinforcing body extending between the terminal fittings. Preferably, however, the reinforcing body and parts of the abrasion-resistant body are enclosed throughout their lengths by a body of a resin composition or other tracking-resistant material.

Abstract: A method for making insulators, comprising the steps of forming a bar from a fiber glass mass impregnated with a thermosetting resin, carrying out the complete polymerization or curing substantially for the major portion of the bar length and maintaining at least one end thereof cooled at a lower temperature than the complete polymerization or curing temperature for said resin. The bar so formed is inserted in an insulating covering and a terminal fitting is applied to said uncured end of the bar, widening the fiber glasses of the uncured end of the bar against a divergent or flared surface of the terminal, and a successive step of complete polymerization or curing is carried out for said bar.