Abstract: The end flange (16) of the first encasing part (10) of the gas-insulated high-tension installation is an outer flange and includes through bores (34). A first securing ring (18) is provided on the end-face side of the end flange (16). The securing ring holds a first insulator (28). The first securing ring (18) includes through bores (36) which are in alignment with the through bores (34) and which have a stepped configuration. The step forms, in each instance, a counterabutment (42), which cooperates with the abutment (44) of the respective threaded bolt (38). To secure the first securing ring (18) on the first encasing part (10), the abutment (44) rests on the counterabutment (42) and, on the other side, the threaded bolt (38) is supported by the nut (48) on the end flange (16).

Abstract: For each phase, a metal-clad line comprises a phase conductor surrounded by an aluminum sheath, with each aluminum sheath being surrounded by a sheath which is gas-tight relative to the outside. The inside of said gas-tight sheath(s) is/are filled with a gas having good dielectric properties. The aluminum sheath is made up of two half-shells with each half-shell being formed by a folded strip whose section is in the form of a semicircle terminated at each end by a shoulder and a flat, with the two half-shells being juxtaposed and assembled to each other via their flats. The invention also provides a method of manufacturing the metal-clad line which is particularly applicable to underground metal-clad lines.

Abstract: A gas insulated electrical apparatus comprises a hermetic sheath having a plurality of electrically conductive sheath sections each including flanged ends and a fastening device for fastening the flanged ends of the sheath sections together. A high voltage conductor is electrically insulatably supported within the sheath sections by an electrically insulating spacer which has a substantially uniform circumferential flange portion and is hermetically and securely held at the outer periphery thereof between the flanged ends of the sheath sections. An electrically insulating gas is disposed within the hermetic sheath. An electrically insulating member is interposed between at least one of the flanged ends of the sheath sections and the circumferential flange portion of the insulating spacer such that one portion of the electrically insulating member is exposed inwardly with respect to the hermetic sheath.

Abstract: A gas insulated electrical apparatus comprising a hermetic sheath filled with an electrically insulating gas having a plurality of electrically conductive sheath sections including hermetically fastened flanged ends. A high voltage conductor is electrically insulatably supported within the sheath by an electrically insulating spacer which is hermetically and securely held at its outer periphery between the flanged ends of the sheath sections. An electrically conductive trap ring is inserted between at least one of the flanged ends of the sheath sections and the outer periphery of the spacer. The trap ring defines, between the trap ring and the spacer, a low electric field particle trap in which a low electric field is formed and in which electrically conductive particles can be trapped and retained.

Abstract: A high-voltage line which includes a conductor supported in a metal encapsulation which is filled with insulating gas and which consists of pipe sections, the ends of which are welded together in a gas-tight manner at specially formed annular mating surfaces. A high-voltage conductor in the interior of the metal encapsulation is supported on partitioning insulators which divide the metal encapsulation into axially spaced cylindrical spaces. Between every two partitioning insulators one or more support insulators are arranged, each of which is located in a distinctly formed annular space. The body of the support insulator is comprised of insulating material having openings in it. The mating surfaces of the two pipe ends are separated by a V-shaped annular gap and are welded together by a welding seam which fills the annular gap. The welding seam has a root which extends annularly and which is electrically in contact with the metallic outer edge of the partitioning insulator or support insulator.

Abstract: A disk, or circular-cone-shaped insulating spacer for gas insulated equipment wherein a portion of the insulating spacer, which is secured to a metal sheath, is greater in thickness than the other portion of the spacer. The insulating spacer is brought into contact with the metal sheath through portions of the metal sheath which are outward of arcuate portions of flanges formed on said metal sheath. The distance between opposed flange surfaces which are formed in said metal sheath may be larger in the outside portion of the metal sheath than that in the inside portion of the metal sheath. The insulating spacer is brought into contact with the metal sheath through the outside portion of the metal sheath.

Abstract: A metal-clad electric installation for high tension use includes a metallic housing containing a conductor supported by an insulator and surrounded by an insulating gas. The metallic housing has adjacent sections which are joined by pairs of connected flanges. The insulator has an external border which is interposed between the flanges of two successive sections of the housing and is secured thereto by bolts passing through aligned openings in the flanges and external border, thereby partitioning the housing into tight compartments. In order to dismantle a section without affecting the sealed condition of the adjacent section, the bolts are replaced by screws which are screwed into small nut plates inserted into slots provided in the interface of the external border and the flanges.

Abstract: Permeation of water between inner and outer insulating jackets of an elongate electrical heater or other device along a metallic braid between the jackets is limited by means of a water-blocking section. The water-blocking section is generally placed near the connected end of the device to prevent water from reaching the connection. In the water-blocking section, the outer jacket is removed and an insulating sleeve, preferably a heat-shrunk polymeric sleeve, is placed over the exposed length of the inner jacket and the ends of the outer jacket. A water-proof sealing material is placed between the sleeve and part only of the exposed inner jacket. In this way, water which permeates between the jackets to the water-blocking section is prevented from passing through the section but is permitted to escape from the device.

Abstract: A composite profile spacer for use in compressed gas insulated co-axial electrical cables. The cables have a central conductor and an outer envelope conductor and an insulating gas contained therebetween. The spacer comprises a composite profile shaped body formed of an electrically insulating material and extends radially between the central conductor and the envelope conductor to support the central conductor substantially concentric with the envelope conductor. The body has a disc section configuration in a first support section adjacent the central conductor, and a cone-section configuration in a remaining support section extending to the envelope conductor whereby to obtain substantially uniform field distribution and low field intensity on the opposed surfaces of the spacer. The contact angle between the opposed surfaces and the central conductor is approximately 75.degree. and the insulating material is an epoxy having a relative dielectric constant of 5 or higher.

Abstract: A partition insulator is disclosed having a seating in at least one insulator holder. A specific predetermined rupture behavior is provided for the partition insulator as a result of outside forces acting on the insulator at a specific quantity and direction such as, for example, gas pressure. A corresponding support (or gripping or solid gripping) of the partition insulator is provided whereby at least on the insulator, on the insulator holder or between these two parts, bearing points (or bearings) are arranged in a suitably distributed manner. The gripping of the partition insulator is accomplished herewith by the insulator holder alone or by both the insulator holder and a fastening ring which holds the partition insulator together by both threaded bolts and nuts. The partition insulator is preferably used as a pressure relief device in pressurized gas-insulated high-voltage switchgears having a metal switchgear casing.

Abstract: A high voltage cable filled with an insulation gas under an operating pressure of more than 1 Bar, in which one or more conductors are supported by insulators, embedded in a tubular sheath of interconnected rigid elements and in which the gas-filled spaces of adjacent segments are connected together through a sealing element which is open under operating conditions and is closed when the pressures in the adjacent segments differ by more than a predetermined pressure difference.