JPH0644336U - Rubber and plastic insulated cable end processing unit - Google Patents

Abstract

(57) [Summary] [Purpose] In the terminal treatment section of rubber and plastic insulation cables that have an external semi-conductive layer for easy peeling, etc.
The concentration of electrical stress at the stripped end of the outer semiconductive layer is relieved, variation due to the skill of the operator is reduced, and the working time is shortened. [Structure] A semiconductive heat-shrinkable tube 13 is fitted on the cable insulator 10 at an appropriate distance from the peeling end 12 of the outer semiconductive layer 11 which is easy to peel off, and is contracted and adhered by heating. There is. In addition, a winding layer 14 of a semiconductive polyethylene tape is provided so as to extend from the end of such a layer of the semiconductive heat shrinkable tube 13 over the outer semiconductive layer 11 to provide electrical continuity. Then, a mold stress cone is inserted and fitted on such a processing portion, and further, required processing is performed to obtain a connection portion.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a rubber or plastic insulation cable end treatment section, and more particularly to a termination section applied to a prefabricated type connection section of a high voltage CV cable (crosslinked polyethylene insulation cable) of 66 KV or more.

[0002]

[Prior art]

 In recent years, prefabricated connections have been made for the purpose of size reduction, labor saving, or stabilization of characteristics when forming connecting parts such as straight lines, branches, or ends of rubber or plastic insulated cables such as CV cables. In this method, a pre-molded insulator (mold stress cone) is inserted around the outer circumference of the cable insulator, where the outer semiconductive layer is stripped and exposed, and terminal treatment such as insulation is performed.

However, in a high-voltage CV cable of 66 KV or more, the outer semiconductive layer is formed by extrusion and is fused tightly to the cable insulator (bond type), so that the outer semiconductive layer can be stripped off. Requires skill of workers. Further, the performance of the terminal treatment portion is greatly affected by the smoothness of the surface of the cable insulator, but it was difficult to finish the surface of the insulator smooth in the above-mentioned cable having the bond-type outer semiconductive layer. Therefore, it has recently been considered that by making the outer semiconductive layer of the cable easy to peel (free stripping), the skill of stripping work is unnecessary and the smoothness of the surface of the cable insulator is improved.

[0004]

[Problems to be solved by the device]

 However, in the terminal treatment part of the cable that has an easily peelable outer semiconducting layer, the stripped end of the outer semiconducting layer becomes an edge (a sharp protrusion), so stress concentrates on this part. However, there is a problem that the electrical characteristics are deteriorated. Therefore, the following processes have been conventionally performed manually to reduce the concentration of electrical stress. That is, as shown in FIG. 4, after wrapping the semiconductive polyethylene tape in 1/2 wrap from the cable insulator 1 toward the end (edge) 3 of the outer semiconductive layer 2, The semiconductive mold layer 4 was formed by heat-molding the wound layer.

However, in such a method, it takes a lot of time and time to form the semiconductive mold layer 4, and the outer semiconductive layer 2 is easily peeled off, so that the performance is made uniform and the working time is shortened. It was not possible to take full advantage of such effects.

Further, as a relatively simple treatment method, as shown in FIG. 5, a coating layer 5 of a semiconductive coating material is provided from the cable insulator 1 to the outer semiconductive layer 2, and A semi-conductive adhesive polyethylene tape is wrapped back and forth for one reciprocal wrap, and a semi-conductive silicone rubber 7 is applied between the tape winding layer 6 and the end of the outer semi-conductive layer 2 to form a minute gap. It was also buried. However, in this method, there is a possibility that the winding layer of the adhesive polyethylene tape winding layer 6 may be displaced or a gap may be formed between the winding layers because the adhesive polyethylene tape itself is thick.

The present invention has been made in order to solve these problems, and the concentration of electric stress at the peeled end of the outer semiconductive layer, which is easy to peel off, is relieved, and the work is easy and the operator can do it. It is an object of the present invention to provide a terminal processing unit for rubber and plastic insulated cables, which reduces the variation due to the skill level and greatly shortens the working time.

[0008]

[Means for Solving the Problems]

 The terminal treatment portion of the rubber and plastic insulated cable of the present invention is directly exposed to the stripped end of the outer semiconductive layer which is easy to peel off or through another semiconductive treatment layer on the exposed cable insulation. It is characterized in that a layer of semiconductive heat-shrinkable tube is provided so as to make electrical contact with the mold stress cone.

[0009]

[Action]

 In the end treatment part of the rubber and plastic insulated cable of the present invention, a layer of semiconductive heat-shrinkable tube is provided on the exposed cable insulator stripped in steps, and this layer is easy to peel off. The external semiconductive layer is in electrical contact with the stripped edge of the external semiconductive layer, either directly or through another semiconductive treatment layer coated on the stripped edge. By concentrating the electrical stress on the stripped end where the edge of the is formed, and by inserting the mold stress cone on it, a terminal with good insulation performance can be obtained.

[0010] Further, since it is not necessary to have the skill of forming the semiconductive heat-shrinkable tube layer together with the peeling of the outer semiconductive layer, there is no variation regardless of the skill of the worker, and the terminal having excellent characteristics. A processing unit is obtained, and the working time is greatly reduced.

[0011]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a vertical cross-sectional view showing a terminal processing unit of a high voltage CV cable according to an embodiment of the present invention.

In the figure, reference numeral 8 indicates a CV cable having an easily peelable outer semiconductive layer, the end of which is stepped off to expose the cable conductor 9, the cable insulator 10, the outer semiconductive layer 11, etc. in order. Has been done. Then, a semiconductive heat-shrinkable tube 13 made of polyethylene or the like having a wall thickness of about 0.5 mm is covered on the cable insulator 10 at a distance of about 20 mm from the stripped end 12 of the outer semiconductive layer 11. It is fitted and shrinked and adhered by heating. Further, a winding layer 14 of a semiconductive polyethylene tape is provided so as to extend from the end of such a layer of the semiconductive heat-shrinkable tube 13 over the outer semiconductive layer 11, and thereby the outer semiconductive polyethylene tape is wound. Electrical conduction is established between the conductive layer 11 and the semiconductive heat shrinkable tube 13. Reference numeral 15 in the figure indicates an internal semiconductive layer.

In the terminal treatment section of the embodiment thus configured, the outer semiconductive layer is formed by the semiconductive heat shrinkable tube 13 layer and the winding layer 14 of the semiconductive polyethylene tape provided thereon. Since the concentration of electrical stress at the stripped end 12 of 11 is relaxed, by inserting a mold stress cone such as a rubber mold stress cone on top of this, there is no concentration of electric field and good insulation performance is achieved. You can get various connections. Moreover, since the outer semiconductive layer 11 can be easily peeled off and removed, and also the formation of the semiconductive heat shrinkable tube 13 layer and the semiconductive polyethylene tape winding layer 14 is not required to be done by an operator. A terminal processing unit with no variations and excellent performance can be obtained, and the working time can be greatly reduced. Further, by peeling off the outer semiconductive layer 11, an extremely smooth extruded surface of the cable insulator 10 is exposed, and a semiconductive treatment layer such as a semiconductive heat shrinkable tube 13 layer is provided thereon. Therefore, when the mold stress cone is inserted, inconveniences such as voids and uneven surface pressure do not occur. Furthermore, by adjusting the thickness of the semi-conductive polyethylene tape winding layer 14 according to the inner diameter of the mold stress cone, the diameter can be easily adjusted, and the adhesion with the mold stress cone can be improved. Can be improved.

Next, another embodiment of the present invention is shown in FIGS. 2 and 3, respectively.

In the embodiment shown in FIG. 2, the easily peelable outer semiconductive layer 11 is peeled off so that the end portions thereof are slightly floating from the outer peripheral surface of the cable insulator 10. The end of the semiconductive heat shrinkable tube 13 layer is inserted into the gap between the end of the semiconductive layer 11 and the cable insulator 10. That is, the semi-conductive heat-shrinkable tube 13 having a small clearance with respect to the outer diameter of the cable insulator 10 is insulated so that one end of the heat-shrinkable tube 13 enters below the stripped end 12 of the outer semi-conductive layer 11. It is fitted on the body 10 and is brought into close contact with the cable insulator 10 by heat shrinkage. Further, the winding layer 16 of the semiconductive suppressing tape is provided on the overlapping portion of the semiconductive heat shrinkable tube 13 and the outer semiconductive layer 11 so that the outer semiconductive layer 11 is prevented from rising. And the outer peripheral surface is formed smoothly.

In an embodiment constructed in this way, a layer of semiconducting heat-shrinkable tubing 13 is provided underneath the stripped end 12 of the outer semiconducting layer 11 and is superposed. Since the winding layer 16 of the semiconductive suppressing tape is provided on the portion, the concentration of the electrical stress at the end of the outer semiconductive layer 11 is relieved, and the mold stress cone should be inserted on it. As a result, it is possible to obtain a connection portion with good insulation performance without concentration of an electric field. Further, since the semiconductive treatment layer such as the semiconductive heat-shrinkable tube layer 13 does not need to be matured, it is possible to obtain a terminal treatment portion having no variation and excellent characteristics in a short time.

Furthermore, in the embodiment shown in FIG. 3, the peeling end 12 of the easily peelable outer semiconductive layer 11 is chamfered by a suitable jig, and such outer semiconductive layer 11 is formed. A semi-conductive heat-shrinkable tube 13 is fitted over the cable insulator 10 from the end portion thereof and is adhered by heating.

In an embodiment constructed in this way, the stripped end 12 of the outer semiconducting layer 11 is chamfered so that the edge disappears, and on top of that the semiconducting heat-shrinkable tube 13 is provided. Since the layers are formed in close contact, the concentration of electrical stress at the end of the outer semiconductive layer 11 is relieved, and by inserting a mold stress cone on it, there is no concentration of electric field and good insulation performance is achieved. A connection is obtained. Further, since the outer semiconductive layer 11 can be easily peeled off and no skill is required to form the semiconductive heat-shrinkable tube 13 layer, it is possible to obtain a terminal treatment section having no variation and excellent characteristics in a short time. .

It should be noted that, in the above-mentioned examples, an interface in which a minute void may be generated, that is, a semiconductive heat shrinkable tube 13 layer or a semiconductive polyethylene tape winding layer 14 is used. Apply semiconductive paint, semiconductive silicone oil, semiconductive silicone gel, etc. to the interface between the treatment layer and the cable insulator 10, or the interface between the semiconductive treatment layer and the outer semiconductive layer 11. The electrical characteristics can be further improved by filling the voids by filling.

[0021]

[Effect of device]

 As described above, in the terminal treatment portion of the rubber and plastic insulated cable of the present invention, the concentration of electrical stress at the stripped end of the outer semiconductive layer, which is easy to peel off, is relieved. A prefabricated type connection with good insulation performance can be obtained by inserting a mold stress cone into and then performing the required processing. Moreover, it is easy to form the semi-conductive treatment layer such as the semi-conducting heat-shrinkable tube together with the peeling work of the external semi-conducting layer, and no skill is required. Can be obtained at.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a terminal processing unit of a CV cable according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing a CV cable terminal processing unit according to another embodiment of the present invention.

FIG. 3 is a vertical cross-sectional view showing a CV cable terminal processing unit according to another embodiment of the present invention.

FIG. 4 is a conventional C having an easily peelable outer semiconductive layer.
FIG. 3 is a vertical cross-sectional view showing a terminal processing unit of a V cable.

FIG. 5 shows a conventional C having an easily peelable outer semiconductive layer.
The longitudinal cross-sectional view which shows another example of a V cable terminal processing part.

[Explanation of symbols]

 1, 10 ... Cable insulator 2, 11 ... External semiconductive layer that is easy to peel off 3 ... Edge 4 ... Semiconductive mold layer 5 ... Semiconductive coating layer 6 ………… Semi-conductive adhesive polyethylene tape winding layer 7 ………… Semi-conductive silicone rubber 8 ………… CV cable 9 ………… Cable conductor 12 ………… Stripping end 13 ………… Semi-conductive shrink tube 14 ……… Semi-conductive polyethylene tape winding layer 15 ………… Inner semi-conductive layer 16 ……… Semi-conductive holding tape winding layer

Claims (3)

[Scope of utility model registration request] 1. A stripped and exposed cable insulator,
A layer of semi-conductive heat-shrinkable tube is provided, and this layer is in electrical contact with the stripped end of the external semi-conductive layer through another semi-conductive treatment layer, and a mold stress cone is inserted on the outer circumference. A terminal processing part for rubber and plastic insulated cables that are fitted. 2. A stripped and exposed cable insulator,
A layer of semi-conductive heat-shrinkable tube is provided such that the end is inserted below the stripped end of the outer semi-conductive layer, and the semi-conductive heat-shrinkable tube spans the stripped end of the outer semi-conductive layer. A terminal processing section for rubber and plastic insulated cables, characterized in that a conductive stress suppressing layer is provided, and a mold stress cone is fitted around the outer periphery. 3. A chamfered stripped end of the outer semiconductive layer and a layer of semiconductive heat shrink tubing over the stripped end on the exposed cable insulation. The end processing part of the rubber and plastic insulated cable is characterized in that the mold stress cone is inserted into the outer periphery.