High-voltage insulator

Abstract

A high-voltage insulator has at least two separate insulators that can be joined to create a post and that each have an essentially rotation-symmetrical support tube made of glass-fiber-reinforced epoxy resin and having an empty internal space, respective top and bottom metallic flanges that surround top and bottom ends of the respective support tube and close the respective tube's empty internal space with an air-tight seal relative to the outer atmosphere, and a shielding of silicone that fits around each support tube. A tubular coupling piece connects the at least two insulators in such a way that the respective empty internal spaces of the at least two insulators form a common gas space and pressure between the spaces is equalized through the coupling piece.

Claims

1. A high-voltage insulator comprised of: at least two separate insulators that can be joined to create a post and that each have an essentially rotation-symmetrical support tube made of glass-fiber-reinforced epoxy resin and having an empty internal space, respective top and bottom metallic flanges that surround top and bottom ends of the respective support tube and close the respective tube's empty internal space with an air-tight seal relative to the outer atmosphere, and a shielding of silicone that fits around each support tube, a tubular coupling piece connecting the at least two insulators in such a way that the respective empty internal spaces of the at least two insulators form a common gas space and pressure between the spaces is equalized through the coupling piece; and at least one fastener anchoring the coupling piece to one of the flanges.

2. The high-voltage insulator according to claim 1, wherein the coupling piece is a detachable plug-type connector.

3. The high-voltage insulator according to claim 1, wherein each internal space of each insulator is filled with insulating gas.

4. The high-voltage insulator according to claim 1, wherein the bottom flange of the bottom insulator includes a connection point to enable filling with insulating gas or connection to a monitoring device.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) By way of example, the following describes the invention in more detail with reference to drawings. Therein:

(2) FIG. 1 is a schematic section through a multipart post insulator according to the invention;

(3) FIG. 2 is a detail view of the coupling piece according to the invention.

SPECIFIC DESCRIPTION OF THE INVENTION

(4) FIG. 1 is a vertical section through a hollow composite insulator, i.e. one that can be assembled out of a plurality of separate insulators 1.1 and 1.2. Each of the at least two hollow composite top and bottom insulators 1.1 and 1.2 here comprises a respective essentially rotation-symmetrical support tube 2.1 and 2.2 that is generally made of glass-fiber-reinforced epoxy resin. An undulating silicone shielding 8.1 and 8.2 is provided on the outsides of the support tubes 2.1 and 2.2. Metallic flanges 3.1, 3.2, 4.1, and 4.2 made for example of aluminum are mounted on respective ends, i.e. on the upper and lower ends of the support tube 2.1 and 2.2 so as to provide positive engagement by externally surrounding the support tubes and being sealed thereto. The bottom flange 3.1 of the bottom insulator 1.1 here has a solid base. In addition, a connection 5.1 for an unillustrated monitoring device is provided in the solid base region of the bottom flange 3.1. The connection point 5.1 is designed so that it can alternatively also be used for filling empty internal spaces 6.1 and 6.2 of the top and bottom insulators 1.1 and 1.2 with insulating gas. This is possible according to the invention since a coupling piece 7 designed for example as a plug-type connector can create a gas-permeable connection between the top and bottom insulators 1.1 and 1.2. The bottom flange 3.2 of the top insulator 1.2 has a shape complementary to that of the top flange 4.1 and they engage each other here in such a way that a vertical mechanical positive guidance is provided first when the two top and bottom insulators 1.1 and 1.2 are fitted together before the actual gas-permeable connection is created by the coupling piece 7. The fact that now only one common gas space thus exists inside the two top and bottom insulators 1.1 and 1.2 means that now only the one common gas space for the complete multipart post insulator 1.1 and 1.2 needs to be checked during servicing by the unillustrated monitoring device that includes at least one pressure sensor. This saves the installation operator not only time but also expense. In order to secure them in place, the two flanges 3.2 and 4.1 are secured together for example by detachable screw fasteners. Throughgoing holes are provided in flange rings 9.1 and 9.2 for this purpose.

(5) FIG. 2 is a detail view of the coupling piece 7 according to the invention, comprised essentially of a first coupling part 22 and a second coupling part 25. The top part of FIG. 1 shows how the bottom flange 3.2 of the top insulator 1.2 can be fitted with the top flange 4.1 of insulator 1.1. In order to prevent insulating gas from escaping between the two flanges 3.2 and 4.1 in the region of coupling piece 7, a groove 29 is formed concentrically around the coupling piece 7 and holds a ring seal 30 can be inserted so as to create a gas-tight connection.

(6) The bottom flange 3.2 of the top insulator 1.2 is formed with a hole 20 into which the tubular first coupling part 22 is fitted. This first coupling part 22 furthermore has a circumferential collar 21 on its end juxtaposed with the flange 4.2. In addition, a plurality of circumferential grooves 23 are formed on the outer and inner surfaces of the tubular first coupling part 22 so as to enable annular sealssuch as for example ring sealsto be provided therein, although only parts of the ring seals is shown in FIG. 2.

(7) Opposite the opening 20, the top flange 4.1 of the bottom insulator 1.1 has another hole 24 into which the second coupling part 25 is fitted. The second coupling part 25 is also essentially tubular and has a collar 26 that can be screwed onto the top flange 4.1 of the bottom insulator 1.1. The actual end of the essentially tubular second coupling part 25 turned toward the bottom flange 3.2 of the top insulator 1.2 projects here by a certain distance into the tubular first coupling part 22. The inside diameter of the first coupling part 22 and the outside diameter of the second coupling part 25 are such that they differ from each other only by a few tenths of a millimeter where they axially overlap with the result that no insulating gas can escape between them. This is also true because a supplemental seal 28 is provided in one of grooves 23.