JPS5828435Y2 - Internal cooling cable conductor connections - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in the conductor connections of internally cooled cables.

Recently, as shown in FIG. 1, an internal cooling cable has been developed in which a sheath 4 is provided around the outer periphery of a refrigerant pipe 1 via a conductor 2 and an insulating layer 3.

This internal cooling cable has the advantage that the power transmission capacity can be increased because the conductor is cooled by flowing a refrigerant such as water into the refrigerant pipe 1.

Note that the sheath 4 is filled with insulating oil different from the refrigerant.

Conventionally, in order to connect the above-mentioned internal cooling cable, as shown in FIG. 2, the refrigerant pipes 1 and the conductors 2 are welded to each other, an insulation reinforcing layer 5 is provided thereon, and an external part 6 is attached to the outside thereof. There is.

However, in the above connection part, there is a problem in that the welding heat generated when the conductors 2 are welded to each other melts the welded connection part of the refrigerant pipe 1 that was previously welded to each other, or the refrigerant pipe 1 itself.

That is, the refrigerant pipe 1 is made of aluminum for flexibility and ease of bonding, and the conductor 2 is made of copper, and the melting point of copper (1083°C) is higher than the melting point of aluminum (660°G). Therefore, the refrigerant pipe 1 or its bath-connected portion will melt due to the welding heat between the conductors 2.

The present invention has been devised in view of the above-mentioned problems, and is intended to provide a conductor connection portion for an internal cooling cable that can be easily connected and that can ensure airtightness of the refrigerant pipe.

Hereinafter, one embodiment ψU of the present invention will be explained in detail with reference to FIGS. 3 and 4.

Figure 3 shows a cross section of the conductor connection, and shows the refrigerant pipe 1.
A core metal pipe 7 is arranged on the inner surface of the holder.

The core pipe 7 is made of stainless steel, iron, or an inorganic material, and has an outer diameter slightly smaller than the outer diameter of the refrigerant pipe 1, and has a plurality of ring-shaped grooves 8 on its outer periphery. It is a provision.

A backing 9 is attached to the groove 8, and the backing 9 is in close contact with the inner surface of the refrigerant pipe 1 and the outer surface of the core metal pipe I to maintain airtightness between them.

The backings 9 are arranged inwardly of each refrigerant pipe 1 to be connected, and the number thereof is not particularly limited.

Further, a compression sleeve 10 is disposed on the outer surface of the conductor 2, and by compressing the compression sleeve 10, the conductor 2, refrigerant pipe 1, and core metal pipe 7 are compressed.

Due to this compression, the packing 9 interposed between the inner surface of the refrigerant pipe 1 and the outer surface of the cored metal pipe 7 maintains the airtightness.

Although not shown, an insulation reinforcing layer and a connection box are provided on the outer periphery of the compression sleeve.

FIG. 4 shows another embodiment ψ11 of the present invention, which differs from the previous embodiment in that it is longer than the length of the core metal sleeve 4, and backings 9' are attached to both ends of the core metal sleeve 4. .

If the core sleeve 7 is lengthened and the backings 9' are attached to both ends of the sleeve 7, no harmful stress will be applied to the backings 9' at both ends due to the compression of the compression sleeve 4.
It has the advantage that airtightness can be maintained stably for a long period of time.

Next, to show a specific example of the present invention, an aluminum pipe with an inner diameter of 40 mm and an outer diameter of 44 mm was used as a refrigerant pipe, and a 6-segment conductor 2500 was provided around its outer circumference.

On the other hand, as a cored pipe, the outer diameter is 39.6 mm and the inner diameter is 271 ft.
A stainless steel pipe having a length of 150 mm and having a total of 4 ring-shaped concave grooves, 2 each on the left and right from the center, was prepared.

An 01J ring was attached to the groove of this cored pipe.

The cored metal pipe with the 01J ring attached thereto was inserted into the inner surface of the refrigerant pipe.

A copper compression sleeve having a length of 240 mm and a thickness of 10 mm was attached to the outer circumference of the conductor, and the copper compression sleeve was compressed.

As a result, in a test of the airtightness of the refrigerant pipe and the core metal sleeve, a degree of vacuum of up to 10'' mrnHg was obtained and the airtightness was sufficient to withstand a pressure of 15-0 gage pressure.

Also, the tensile strength of the conductor connection part is 90% of that of the non-connection part.
It was about φ, which was a nearly satisfactory result.

Furthermore, the work time was reduced to about 1/3 compared to the conventional method.

As described above, in the conductor connection portion of the internal cooling cable according to the present invention, since the backing is arranged on the inner surface of the refrigerant pipe and the outer surface of the core metal pipe, airtightness can be maintained between the two.

Further, since the conductors are compressed and connected by compression of the compression sleeve, there is an advantage that the work of connecting the conductors can be easily performed.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of an internal cooling cable, Fig. 2 is a cross-sectional view of a connection part of a conventional internal cooling cable, and Figs. 3 and 4 are different halves of a conductor connection part of an internal cooling cable according to the present invention. It is a cutaway sectional view. 1 is a refrigerant pipe, 2 is a conductor, 3 is an insulating layer, 4 is a sheath,
7 is the core pipe, 9 is the backing.

Claims (1)

[Scope of utility model registration request] In the conductor connection part of an internal cooling cable in which a sheath is provided on the outer periphery of a refrigerant pipe via a conductor and an insulating layer, a core metal pipe is arranged on the inner surface of the refrigerant pipe via a backing, and is a conductor connection of an internal cooling cable, characterized in that the compression connection sleeve is compression connected.