JPH038034Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an oil stopper connection having a two-chamber structure.

Background of the invention Figure 1 shows an example of an oil stop joint with a two-chamber structure. 10 and 12 are cable cores, and 14 is a conductor connection portion.

An internal condenser cone 16 is provided only on one cable core 10, and an oil stopper cone 1 is provided on the outside of the condenser cone 16.
8 and on which an external capacitor cone 20 is formed.

Reference numeral 22 denotes a shielding metal fitting, whose base 24 is cylindrical, and the portion 26 beyond it is conical. The base 24 is in circumscribed contact with the tip 19 of the oil stopper tube 18, and the tip of the conical portion 26 is in contact with the conductor 13 of the cable core 12 on the opposite side.

Shielding fitting 22 from above external capacitor cone 20
and over the cable core 12 on the opposite side,
A reinforcing insulating layer 30 is formed by wrapping oil-impregnated paper. At that time, the "fitting" between the shielding fitting 22 and the oil-impregnated paper
In order to improve this, crepe paper is first wrapped around the shielding fitting 22, and then oil-impregnated paper is wrapped over that.

Then, the outside thereof is surrounded by an external copper pipe 32 or the like.

By the way, in the oil-stop connection part of the above structure, dielectric breakdown occurs at a low voltage from the shoulder 28 (the part transitioning from the cylindrical part to the conical part) of the shielding fitting 22 in the direction along the oil-impregnated paper. This phenomenon was observed.

This invention aims to solve these problems and improve the electrical performance of the oil stop joint.

Structure of the invention As shown in FIG. 2, the solid insulating layer 3
4.

The solid insulating layer 34 is preferably made of a material that has a dielectric breakdown strength higher than that of the oil-impregnated paper in the longitudinal direction and has good adhesion to the metal shielding fitting 22.

In particular, if crepe paper impregnated with epoxy resin is used as the material, it is convenient in terms of molding process.

Additionally, the surface of the solid insulator layer 34 is shaped like a step 36.
to make it easier to wrap the oil-soaked paper.

This layer of solid insulator 34 can be previously integrally formed on the shield fitting 22 in the factory.

The shielding fitting 22 is disassembled into parts A and B, for example, and assembled on site.

Effects of the invention (1) Since the dielectric breakdown strength of oil-impregnated paper in the direction along the layer is not very high, when dielectric breakdown occurs near the shoulder 28 where the electric field is most concentrated, it continues to progress in the direction along the layer. As mentioned above, it is thought that it may be destroyed by low voltage.

However, in the present invention, since the solid insulating layer 34 is provided in close contact with at least the vicinity of the shoulder 28 of the shielding fitting 22, dielectric breakdown is less likely to occur in the vicinity of the shoulder 28. Since the layer 34 suppresses the progress of dielectric breakdown, the problem of breakdown at low voltages as described above is solved.

(2) Since the outer circumferential surface of the solid insulating layer 34 is made step-shaped in advance, the reinforcing insulating layer 30 can be formed using wide oil-impregnated paper, which improves the efficiency of the paper-wrapping work of oil-impregnated paper. be able to.

[Brief explanation of the drawing]

FIG. 1 is a general explanatory diagram of a two-chamber structure oil stop joint, and FIG. 2 is an explanatory diagram of the main parts of an embodiment of the present invention. 10, 12...Cable core, 13...Cable conductor, 16...Internal capacitor cone, 18...
...Oil stopper pipe, 20...External condenser cone,
22... Shield fittings 22, 28... Shoulder, 30... Reinforcement insulation layer, 34... Solid insulator layer.

Claims (1)

[Claims for Utility Model Registration] (1) An oil stopper pipe 18 is provided outside the end of the cable core 10 on one side, and a base portion is provided from the tip of the oil stopper pipe 18 to the cable conductor of the cable on the opposite side. A shielding fitting 22 having a cylindrical shape and a conical shape is attached to the oil stopper pipe 1.
In the oil-stop connection box having a two-chamber structure, in which an oil-impregnated paper reinforcing insulating layer is provided from the outside of the shielding fitting 22 and the cable core 12 on the opposite side from the outside of the shielding fitting 22 to the cable core 12 on the opposite side. An oil stop joint box characterized in that a solid insulating layer 34 having a step-like outer circumferential surface is provided in close contact with the vicinity of a shoulder 28 transitioning to a shaped portion. (2) The oil-stop insulating box according to claim 1, wherein the solid insulating layer 34 is made of crepe paper impregnated with epoxy resin.