WO2000035051A1

WO2000035051A1 - Cable joint

Info

Publication number: WO2000035051A1
Application number: PCT/CZ1999/000046
Authority: WO
Inventors: Pavel Kupilík
Original assignee: Kupilik Pavel
Priority date: 1998-12-10
Filing date: 1999-11-26
Publication date: 2000-06-15
Also published as: CZ292409B6; CZ9804063A3

Abstract

The cable joint which connects the conductive cores (2) of single - conductor as well as multiconductor cables where the connection (1) of the core (2) of the conductor is covered by insulating tube (5) in such a way that the edge of the insulating tube (5) overlaps, by both ends, the original insulation (4) of the conductor, said connection (1) being made in cold conditions at temperatures of - 50 up to + 90 °C and under pressure which is higher than 50 MPa.

Description

C a b l ε J o i n t

Field of the Technique

The invention solves a cable joint which connects solid conductive cores even of mu 1 t i conductor cables.

Description of the Prior Art

Till the present time, the cable conductors have been joined by a previously insulated conductor jointer. This one consists of an insuladed tube in the centre of which there is a joint of a conductive cabel core. The free edges diameter of the insulation tube is larger than that of its centre. The stripped-off cable conductor ends are shifted into free edges of the conductor jointer as far as the conductive core joint. The free tube edges overlap the stripped-off part and partially even the original cable conductor insulation, too. The point to be connected is mechanically joined by pressing which is followed by heating by means of a hot-air device as a result of which the tube shrinking occurs.

A further method, being used especially for cable cores with larger diamaters, is rooted in the core joining principally by bolted joints or in the core joining in a jointer which is pressed to the core. In both cases the connection is fitted with an insulating layer.

The crimping method replaces the formerly applied soldering which endangers health because of generating vapours. The disadvantage of cri ing consists in an enlarged outer joint diameter as compared with neighbouring cable diameter.

Another important disadvantage is the untightness of such conductive connection which represents a source of troubles in extreme conditions, e.g. under influence of aggressive vapours or of high temperatures due to contingent fire in nuclear power plants. Increasing of transitive joint resistance has negative influence especially if a joint, which has been made in such a way, is loaded by current and stressed. Substance of the Invention

The above mentioned disadvantages are eliminated by the cable joint, made in compliance with the invention, which connects conductive cores of single-conductor as well as mu 1 i onductor cables. The substance of the invention in rooted in that the joint of the cold-made conductor core, manufactured at temperatures of - 50 up to + 90 °C of the material to be connected and under pressure which is higher than 50MPa, is overlayed by an insulating tube in such a way that the insulating tube edges overlap the original conductor insulation by both ends .

The advantage of the proposed solution consists in retaining strength and conductivity of the conductor core joint. Another advantage is elimination of ignition danger due to heat caused by the current load of an imperfect conductor joint.

By means of the solution, he core material homogenity is ensured over the whole conductor length, i.e. including the joint point.

Survey of Figures on Drawings

The invention is being explained by means of figures where on Fig. 1. the single-conductor cable joint is presented, on Fig. 2. there is the cable joint with discovered cores and delineated fireproof glass-mica insulation, while Fig. 3. presents a cable joint deta i I .

Examples on the Invention Realization Example 1

The cable joint has been applied in the connection J_ of conductive cores 2 of a s i ng I e—conduct or cable, made in cool conditions, i.e. at the room temperature of 25 °C and under pressure of 80 MPa. This connection J_ is covered by an insulating tube 5_. in such a way that the edges of said tube overlap fay both edges over the edge of the original insulation 4. of the conductor . Because of connecting the cores 2 of the cable, said connection having been made under above mentioned conditions, both ends of cores 2 are mutually driven-in each into another due to which the material is compacted. The diameter of the connection J. equals the core diameter and, in the point of connection J_, the material strength is not decreased.

When making the actual connection, the insulating tube 5_ is being shifted on the original insulation 4. of the conductor and the cores 2 are being connected and the insulating tube 5_ is being shifted over the point of connection.

Example 2

The cable joint, made in compliance with the invention, was applied to connect the conductive cores 2 of a mu I t i conductor cable too, in which a fireproof glass-mica insulation 6. had been located between the core 2 and the original insulation 4. of the conductor, as it is seen on Figs 2. and 3.

The cable joint contains the connection J_ of the cores 2 of each cable conductor, said connection having been made at temperature of + 5 °C and under pressure of 120 MPa.

To the connection J_, the fireproof glass-mica insulation 6_. is added which had been removed before connecting and on it the insulating tube 5_. is situated in such a way that its edges overlap over the original insulation 4_. of the conductor.

The solution was applied for the cable type the operating of which, i.e. in the point of connection and over the whole connecting cable, must keep its functionality even during a fire.

Utilization in industry

The cable joint can be utilized in electrical installations where it is required to ensure the connection conductivity and quality in heavy conditions of cable stressing by mechanical forces and heat .

Because of steady parameters the cable joi t is suitable to connect cables to hermetic sealing bushings of power plant containments. It can be used for cable wiring in tunnel bui 1 d i ngs, too . List of reference numbers

1 - connect i on

2 - core

4 - original insulation

5 - insulating tube

6 - fireproof glass-mica insulation

Claims

PATENT CLAIMS

1. Cable joint which connects the conductive cores (2) of single- conductor as well as mu 1 t i concuct or cables, c h a r a c t e r i — z e d i n t h a t the connection (1) of the core (2) of the conductor is covered by the insulating tube (5) in such a way that the edge of the insulating tube (5) overlaps, by both ends, the original insulation (4) of the conductor, said connection (1) being made in cold conditions at temperatures of - 50 up to + 90 °C and under pressure which is higher than 50 MPa.