DE1640699A1 - End termination for high voltage cables and lines - Google Patents

Description

I D

Cable and Metal Works "1 840

Gutehoffnungshütte Aktiengesellschaft May 24, 67

End termination for high voltage cables and lines

In recent times, high-polymer thermoplastic and cross-linked plastics have been used more and more frequently as insulation for electrical cables and wires. If these cables and lines are required for high-voltage purposes, then it is necessary that the respective cable and line ends are secured by a specially designed high-voltage-resistant end termination. To solve the problem arising from this, namely the high-voltage-proof connection of cable or line insulation and terminating lobe, numerous proposals have already become knownf. For example, attempts have been made to circumvent the difficulties encountered when connecting the cable insulation made of a thermoplastic with a terminal lobe made of cast resin by applying an intermediate layer of isocyanate to the cable insulation at this point before the cable end is cast around the cable end. I ^{1 For} the production of an end termination on the assembly site, however, this means a considerable effort.

Endverschlußwickel prepared to remedy this lack of a thermoplastic plastic led, but so far not because like a secure connection between the cable insulation and the winding only with difficulty or can not be a satisfactory solution, to achieve.

The invention is therefore aimed at overcoming the difficulties mentioned in the manufacture of end terminations for with the help of Thermoplastics or elastomers sheathed high voltage cables or lines a different way. According to the invention, as Abechlußbeule formed by rotation body shrunk onto the insulation of the cable or the letting, love a substantially

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simple assembly through the use of factory-made rotating bodies is above all a high-voltage: ·. it te connection possible between the end lobe and the insulation of the cable or line regardless of the respective insulation material Due to the tight fit achieved as a result of the shrinkage between the end lobe and the insulation, there are air pockets that could give rise to glowing phenomena, largely avoided

The heated and pushed onto the cable or line end of rotation body can be made of a cast resin, porcelain, a thermoplastic or cross-linked plastic, made of a rubber or another shrinkable insulating material suitable for high voltage purposes. As particularly useful However, it has been found that the closing lobe is made of an insulating material in order to achieve a uniform field strength curve produce whose dielectric constant is equal to or at least approximately equal to that of the cable or wire insulation. For this reason it is advantageous z. B. Select end lobes made of this material for cables and lines insulated with polyethylene or polyvinyl chloride.

The rotary body may be formed as a cast solid body in'dem additional potential controlling deposits ^ instance in the form of rings, radiation hoppers and the like. Embedded _f, consisting of conductive material or plastic oc el astic deformable, non-metallic materials conductive in known manner with elektriscl Layers "exist.

In a continuation of the concept of the invention, it is particularly advantageous for the terminating lobe to be arranged concentrically to one another and according to the outer shape of the terminating lobe, to produce tubes that are stepped along their length and their position relative to one another and on the insulation of the cable or line by means of

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shrink is secured. In this way it is possible, among other things, to produce different cable or line diameters on the Compensate for the installation site with appropriate fitting pipes, which are first shrunk onto the insulation.

The invention is based on the end termination shown in Figures 1 and 2 as an embodiment of a single-core, with Polyethylene insulated high voltage line explained in more detail.

The conductor 1 of the high-voltage line is surrounded by insulation 2 made of polyethylene, which is not shown in a Extrusion press has been applied to the conductor. From the end the Ho ^ hsVarinungsleitung her as massive, z. B. cast Rotary body formed end lobe 3 made of polyethylene pushed into the additional potential-controlling deposits can be embedded,

In order to achieve a firm fit of the terminating lobe 3 on the insulation and to avoid the formation of gaps between these parts, the terminating lobe 3 is shrunk onto the insulation. For this purpose one proceeds in such a way that the with. a bore 4 provided conclusion lobe 3 is heated until the bore 4 having a diameter smaller than the outer diameter of the insulation 2, is sufficiently widened so that the rotary body to the high-voltage line anfgeschoben werden- ^J can. When it cools down, the "e" terminal lobe dumps onto the insulation. This ensures a tight fit of the alischlußk'eule, which, as tests have shown, ensures a high-voltage-resistant end termination for a long time even under increased energy-saving stress.

Any remaining small air pockets on the Mating surfaces; can be further reduced in the Aufschi.ebe.il the rotating body on an Isolierfküssigkeit the mating surfaces are applied and removed during the

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is pressed. This liquid also serves as a lubricant to make it easier to slide open. At the bottom of the End lobe 3 is the semiconducting or weakly conductive coating 6, "for example made of graphite, attached to the Shield 7 of the high-voltage line is connected in an electrically conductive manner.

In the embodiment example, the end section is for the interior partitioning shown, however, should such an end termination find free use, then one is known per se Porcelain cover = intended as weather protection.

Deviating from the exemplary embodiment according to FIG In FIG. 2, an end termination is shown in which the insulation 9 made of a butyl rubber is applied to the conductor 8 surrounding it the end lobe 10 is shrunk. This end lobe 10 consists of the individual concentric to one another Tubes 11, the length of which is graduated according to the outer shape of the end lobe.

The surface of each tube, either already factory-made or only shrunk on top of one another at the installation site is expediently metallized in order to achieve a potential control within the terminating lobe. For air gap-free Connection of the individual tubes 11, for. B. from a Low pressure polyethylene, you will get these before sliding them on top of each other expediently wet with a lubricant known, for example, under the trade name Novoid, which is used during the shrinking process at least partially again from the gaps between the individual pipes or the line insulation 9 and these surrounding pipe is pressed out.

At the lower end of the end lobe 10 is again the half- or weakly conductive covering 12 provided with the shield 15 of the high-voltage line electrically connected

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To compensate for different cable or line diameters, a Use a solid end lobe provided with a standard bore that does not directly touch the cable or line insulation, but rather one or more pieces that serve as adapters and tubes that have already been shrunk onto the cable or line are shrunk on. It is also possible to provide the end lobe with known ribs to extend the rollover path.

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Claims (1)

Cable and metal works 1,840 Gutehoffnungshütte Aktiengesellschaft May 25, 1967 1640839 Claims 1. End closure for with the help of thermoplastics, in particular polyethylene, or elastomers, for example butyl rubber, sheathed high-voltage cables or lines in the form of a terminating lobe surrounding the cable or line core, thereby characterized in that the terminal lobe designed as a rotational body on the insulation of the cable or line has shrunk. 2. End termination according to claim 1, characterized in that the end lobe made of an insulating material, preferably one cross-linked plastic, whose dielectric constant corresponds approximately to that of the insulation of the cable or line. 3. End termination according to claim 1, characterized in that the end lobe is designed as a solid body. 4o end termination according to claim 3 »characterized in that in the solid body potential-controlling inserts are arranged. 5. end termination according to claim 1, characterized in that the end lobe is arranged concentrically to one another and corresponding to the outer i ^ orrn of the closing lobe in their Length graded drilling consists of their location to each other and on the insulation of the cable or line by shrink fitting is secured » 6. Endeabschluii according to claim 5, characterized in that Potential-controlling oil inlays are arranged between the individual tubes are. 009835/0588 1640899 7o. End termination according to Claim 6, characterized in that that the individual tubes have a conductive layer on their surface. 8. End termination according to claim 1, characterized in that the end lobe is provided with an electrically conductive coating at its end facing the cable or line which is electrically conductively connected to the shielding of the cable or line. 9. end termination according to one or more of claims 1 to 8, characterized in that the mating surfaces of the bore and those of the individual pipes are wetted with an insulating liquid to avoid air inclusions. ORIGINAL BATHROOM 009835/0 5 86