JPH023666B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for soldering conductors in electric cables such as power cables, and particularly aims to provide a method for soldering cable conductors that allows easy cooling during soldering. It is something to do.

Conventionally, the method using compression sleeves is generally known as a method for connecting conductors of power cables, but the biggest drawback of this method is that when the cable conductors to be connected become large, the outer diameter of the conductor connection part must be increased. However, the finished outer diameter of the insulator applied thereon becomes large.

A method that has been developed to solve this problem and make the outer diameter of the conductor connection part equal to the outer diameter of the conductor is a method in which the end surfaces of the conductor ends are butted against each other and soldered using a soldering alloy.

However, in such a soldering method, since the process is performed at a considerably high temperature, the high heat during the soldering process is transmitted through the conductor, which is a good conductor of heat, and added to the insulator on the conductor, causing the insulator to There was a problem with heat deterioration.

Conventionally, this problem has been solved by increasing the stripping length of the insulator 2 at the end of the cable to be connected to increase the exposed length of the conductor end 1, as shown in Figure 1. The long exposed conductor ends 1 are butted against each other and integrated by soldering using a soldering metal 3 such as silver soldering to reduce the thermal effect on the insulator due to the high heat applied to the conductor during soldering. There is a way.

However, this method not only requires more time and man-hours to strip off the insulator, but also makes the exposed conductor longer than necessary. This method of connecting cables, which is generally carried out at the installation site, is not practical because many machines allow water to enter the insulation.

On the other hand, as a method that does not make the stripping length of the insulator unnecessarily large, as shown in FIG. A half-split type cooling pipe 5 is installed on the exposed part near the side, and the cooling pipe 4
A method has been proposed for absorbing the high heat applied to the conductor end 1 by pouring water into the internal cavity of the conductor. (For example, please refer to Japanese Patent Publication No. 52-45911.) However, in the water cooling method, in order to obtain the desired cooling effect, it is necessary to place the cooling pipe in close contact with the conductor. It is necessary to manufacture cooling pipes of different sizes each time the size changes.
In addition, with this method, the work time required from closely attaching the conductor to pouring water was relatively long, and no reduction in work time could be expected. Furthermore, there is a risk that water droplets may adhere to the conductor when pouring water or draining water after soldering, and extra post-treatment is often required, such as wiping off the adhering water droplets.

In view of the above-mentioned problems of the prior art, the present invention provides a cable conductor which can perform conductor soldering while effectively dissipating the high heat applied to the conductor in a short time and simple process, and which is easy to post-process. The purpose is to provide a soldering method.

That is, the cable conductor brazing method according to the present invention involves directly contacting the exposed portion of the conductor end from the insulator side by peeling off the insulator, but not integrating the flexible metal tape. The flexible metal tape is wound in multiple layers to dissipate the heat applied to the conductor end during soldering, and the wound flexible metal tape is unwound and removed after soldering is completed.

FIG. 3 shows a preferred embodiment of the cable conductor brazing method according to the present invention, in which the end faces of the conductor end 1 exposed by peeling off the insulation from the cable end to be connected are shown in FIG. are butted together, and the soldering process 3 is performed while supplying a brazing alloy at the abutted part. Before soldering, the exposed part of the conductor end 1 closer to the insulator 2 is coated with a material with a thickness of, for example, 0.1 mm. A flexible metal tape 3 made of copper tape is wound in multiple layers in direct contact but not integrated, and the high heat applied to the conductor end 1 during soldering is transmitted through the multilayer winding of the wound metal tape 5. This is done by dissipating heat and reducing the thermal influence on the insulator 2.

As mentioned above, since the metal tape 5 has flexibility, it can be wrapped and used even if the cable conductor size changes.

The metal tape 5 used as a heat dissipating member as described above can be unwound and removed after the soldering process is completed, so that it can be immediately applied to the insulation process for the conductor connection portion.

In that case, the metal tape 5 can be reused.

FIG. 4 shows another preferred embodiment of the cable conductor soldering method according to the present invention, in which the metal tape 5 wound in multiple layers as described above is
The cooling gas is sprayed 6 onto the side surface of the metal tape 5 that is inclined toward the insulator 2 and facing the insulator 2, thereby efficiently absorbing the heat transmitted to the metal tape 5. In this case, by giving an inclination to the wrapped portion of the metal tape 5 and performing gas blowing on the inside of the inclined side surface, the metal tape 5 is not affected by the flame during the brazing process.

According to this method, the heat dissipation effect due to the multilayer winding of the metal tape 5 is increased, and the frontage of the conductor soldering portion is expanded, so that the soldering work can be performed more easily.

In the above two examples, when a cable conductor with a cross-sectional size of 150 mm ² was applied and soldered at a soldering temperature of 800 to 900°C, the temperature at the end of the insulator was as follows. In the example shown in Figure 3, the temperature is 200°C, and in the example shown in Figure 4, it is 180°C.
It was warm at ℃. This is the temperature of the insulator end when soldering is performed without wrapping the metal tape 5.
℃, and the heat dissipation effect of wrapping the metal tape 5 was confirmed.

As explained above, according to the cable conductor soldering method according to the present invention, the high heat at the end of the conductor received during the soldering process is effectively dissipated on the conductor itself, and the heat is transferred to the insulator. It is possible to achieve the desired heat dissipation by using a flexible metal tape as a heat dissipation member and wrapping it in multiple layers without directly contacting the end of the conductor but not integrating it. Because of this effect, the process to form the heat dissipation part can be easily carried out in a short time, and the metal tape used as a heat dissipation material can be used universally without having to make different types even if the conductor size changes. It can be adopted in many countries and is economically advantageous. Further, after the soldering process, it is only necessary to unwind and remove the metal tape, which facilitates post-processing. etc., are of great practical value.

[Brief explanation of drawings]

FIGS. 1 and 2 are explanatory diagrams showing examples of conventional cable conductor soldering methods, and FIGS. 3 and 4 are explanatory diagrams showing two embodiments of the cable conductor soldering method according to the present invention. It is a diagram. In the figure, 1 is a conductor end, 2 is an insulator, 3 is a soldering part, 4 is a cooling pipe, 5 is a multilayer winding part of metal tape, and 6 is a gas blowing means.

Claims (1)

[Claims] 1 A method in which the insulator is stripped off at each end of the cable to be connected and the exposed end surfaces of the conductor ends are brought together and soldered together, and the exposed portion of the exposed conductor end closer to the insulator is soldered. A flexible metal tape is wrapped in multiple layers on top of the conductor in direct contact but not integrated to dissipate the heat applied to the conductor end during soldering, and after soldering is completed, the wrapped metal tape is unwound and removed. A method for soldering cable conductors, characterized by: