JP5554179B2 - Assembly method of power cable end connection - Google Patents

Description

  The present invention relates to a method for assembling a power cable terminal connection portion.

2. Description of the Related Art Conventionally, as a power cable terminal connection part, an oil immersion type terminal connection part in which oil is filled as an insulating filler in a soot tube is known. In this system, if oil leakage occurs, the surrounding environment may be polluted. In recent years, a completely dry type terminal connection portion that does not use oil as an insulating filler has been developed.
As a completely dry type terminal connection part, for example, a terminal connection part in which a gel-like insulating resin such as silicone gel (hereinafter referred to as “gel”) is filled in a soot tube instead of oil is known (for example, Patent Document 1). reference). The gel raw material (referred to as “gel raw material” in the present application) is in a liquid state, but when it hardens and becomes a gel, the fluidity is lost. Therefore, according to the terminal connection portion filled with the gel, there is a risk of environmental pollution as described above. Can be avoided.
By the way, in the termination | terminus connection part filled with the gel, when a bubble exists in a gel, discharge may generate | occur | produce in a bubble part depending on a place, and it may have a bad influence on insulation performance. For this reason, in the termination | terminus connection part to which the said system was applied, when inject | pouring a gel raw material into a soot pipe, the exclusive injection apparatus 300 (for example, refer nonpatent literature 1) as shown, for example in FIG. 10 is used. The injection device 300 includes a static mixer 301 and a pump 302. The main agent A and the curing agent B, which are gel raw materials, are supplied to the static mixer 301 via the pump 302, and after stirring with the static mixer 301, the gel raw material is injected from the lower part of the tub tube 400, whereby air is introduced into the gel raw material. Prevents mixing.

Japanese Utility Model Publication No. 6-80338 Jicable’03A6.4. “New dry outdoor terminations for HV extruded cables”

By the way, as described above, the dedicated injection apparatus has the static mixer 301 and the pump 302, so the apparatus itself becomes large, and accordingly, a space required for the assembly work of the power cable terminal connection portion is required. It was. In particular, since the dedicated injection device is for injecting the gel raw material from the lower part of the soot tube, the main body of the device must be arranged on the side of the soot tube, and more assembly work space is required. However, the actual situation is that the injection device cannot be installed at a site where there is not enough space.
For this reason, the subject of this invention is providing the assembly method of the electric power cable termination | terminus connection part which can abbreviate | omit a dedicated injection | pouring apparatus by inject | pouring a gel raw material by a simple method.

In order to solve the above problems, one aspect of the method for assembling the power cable terminal connection portion of the present invention is:
In the assembling method of the power cable terminal connection portion in which the gel-like insulating filler is filled in the soot tube into which the end portion of the power cable is inserted,
When injecting the gel raw material to be the insulating filler from the upper part of the soot pipe of the power cable terminal connection portion into the soot pipe, the gel raw material is passed through the raw material supply tool provided on the top of the soot pipe. Injected into the fistula,
The raw material supply tool has a tank part in which the gel raw material is stored, and an inlet for injecting the gel raw material in the tank part into the soot tube,
The inlet is formed in a shape along the inner peripheral surface of the soot tube .
In addition, another aspect of the method for assembling the power cable terminal connection portion of the present invention is as follows.
In the assembling method of the power cable terminal connection portion in which the gel-like insulating filler is filled in the soot tube into which the end portion of the power cable is inserted,
When injecting the gel raw material to be the insulating filler from the upper part of the soot pipe of the power cable terminal connection portion into the soot pipe, the gel raw material is passed through the raw material supply tool provided on the top of the soot pipe. Injected into the fistula,
The raw material supply tool has an inlet for injecting the gel raw material into the soot tube,
In the method, the injection port is formed in a shape along the outer peripheral surface of a power cable arranged in the vertical pipe.

  Since the gel material is injected from the upper part of the soot tube into the soot tube, the equipment for injecting the gel material can be arranged above the soot tube, and the space required for the assembly work of the power cable terminal connection is reduced accordingly. It becomes possible to do. Further, according to this method, since gravity can be used, a simple method of pouring the gel material from the upper part of the soot tube without using a dedicated injection device can be adopted.

  When this method is carried out, the gel material is preferably filtered before the gel material is injected into the tubule.

  If the gel raw material is filtered in this way, it is possible to inject the gel raw material into the soot tube in a state in which foreign matters are greatly reduced, and it is possible to suppress the mixing of bubbles into the injected gel raw material.

As a raw material supply tool for injecting the gel raw material from the upper part of the soot tube into the soot tube, a material provided with an inlet for injecting the gel material into the soot tube is preferable. A tank part in which the gel raw material is stored may be connected to the inlet.
Here, as a preferable shape of the injection port, firstly, a shape along the inner peripheral surface of the soot tube is mentioned.

  If the injection port has such a shape, the gel raw material that has passed through the injection port is injected into the soot pipe along the inner peripheral surface of the soot pipe. The layer spreads and thins, increasing the surface area. Thereby, the air remaining in the gel raw material is easily discharged. Moreover, since the gel raw material falls along the inner peripheral surface of the soot tube, the dropping speed of the gel raw material can be slowed by the friction. That is, it is possible to maintain a state where residual air is easily discharged as long as possible. Therefore, air can be removed more reliably.

  Moreover, you may form the said injection port in the shape in alignment with the outer peripheral surface of the electric power cable arrange | positioned in the said soot pipe.

  Even if the injection port has such a shape, the gel raw material that has passed through the injection port is injected into the vertical pipe along the outer peripheral surface of the power cable. Therefore, the gel raw material that flows down along the outer peripheral surface of the power cable. The layer spreads and thins, increasing the surface area. Thereby, the air remaining in the gel raw material is easily discharged. Moreover, since the gel raw material falls along the outer peripheral surface of the power cable, the dropping speed of the gel raw material can be slowed by the friction. That is, it is possible to maintain a state where residual air is easily discharged as long as possible. Therefore, air can be removed more reliably.

  Alternatively, a screen mesh may be provided in the raw material supply tool, and the gel raw material may be filtered through the upper part of the tub tube with the screen mesh.

  Thereby, the filtered gel raw material can be supplied in a soot pipe.

  Preferably, at the time of injecting the gel raw material, the inside of the soot tube is sealed, and the air pressure inside the soot tube is made lower than the external pressure.

Since the pressure inside the soot tube is lower than the external pressure at the time of injecting the gel material, the discharge of the air mixed in the gel material can be expedited.
Further, since the gel material injection speed is increased by the pressure difference, the gel material injection operation can be completed quickly. Thereby, the hardening time of a gel raw material can be taken for a long time during all the processes, and it is easy to ensure the time to wait until the air in a gel raw material is discharged | emitted.

  ADVANTAGE OF THE INVENTION According to this invention, the assembly method of the electric power cable termination | terminus connection part which can abbreviate | omit a dedicated injection | pouring apparatus by inject | pouring gel by a simple system is provided.

It is sectional drawing which shows schematic structure of the power cable termination | terminus connection part which concerns on this embodiment. It is a perspective view which shows schematic structure of the raw material supply tool which concerns on this embodiment. It is a top view which shows the relationship between the injection | pouring part and the inner peripheral surface of a soot pipe at the time of installing the raw material supply tool of FIG. 2 in the upper part of a soot pipe. It is explanatory drawing which shows each process of the assembly method of the power cable termination | terminus connection part which concerns on this embodiment. It is a figure which shows the modification of the raw material supply tool in this embodiment, and is a top view which shows the relationship between the injection | pouring part and the outer peripheral surface of an electric power cable at the time of installing the said raw material supply tool in the upper part of a soot pipe. It is explanatory drawing which shows the positional relationship of the raw material supply tool of FIG. 5, and an electric power cable. It is a figure which shows the modification of the raw material supply tool in this embodiment, and is explanatory drawing which shows the positional relationship of the said raw material supply tool and a conductor extraction rod. It is explanatory drawing which shows the modification of the assembly method of the power cable termination | terminus connection part which concerns on this embodiment. It is a fragmentary sectional view which shows the modification of the power cable termination | terminus connection part which concerns on this embodiment. It is explanatory drawing which shows an example of the exclusive injection apparatus used conventionally.

  The best mode for carrying out the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
Before describing the method for assembling the power cable terminal connecting portion according to the present invention, the power cable terminal connecting portion 1 assembled by the assembling method and the raw material supply tool 100 used at the time of assembly will be described.

  First, the power cable terminal connection unit 1 will be described. FIG. 1 is a cross-sectional view illustrating a schematic configuration of a power cable terminal connection portion 1 according to the present embodiment. In FIG. 1, reference numeral 2 denotes a power cable insulated with rubber or plastic. The power cable 2 is stripped, and the outer semiconductive layer 3, the insulating layer 4, and the conductor 5 are sequentially exposed. Reference numeral 6 denotes a rubber block mounted on the outer periphery of the power cable 2 from the outer semiconductive layer 3 to the insulating layer 4. The rubber block 6 is composed of a semiconductive rubber part 61 for electric field relaxation and an insulating rubber part 62, and is in close contact with the outer peripheral surface of the cable core due to contraction force caused by being expanded in diameter by the power cable 2. 7 is a conductor lead bar that is compression-connected to the conductor 5, 8 is a saddle tube, 9 is an upper fitting that closes the upper opening of the saddle tube 8, 10 is a lower fitting that closes the lower opening of the saddle tube 8, and 11 is integrated with the lower fitting 10 The cable holding tube 12a is a gel-like insulating filler 12a filled in the tub tube 8, and 13 is a gel stopper for preventing the gel raw material 12 from flowing out.

  The soot tube 8 is formed with a number of pleats by covering a cylindrical body made of, for example, FRP with rubber such as silicone rubber.

The gel-like insulating filler 12a is filled in the soot tube 8 by stirring the liquid main ingredient and the curing agent, which are the materials of the gel raw material 12, and injecting them into the soot tube 8, and then curing them. Examples of the commercially available gel raw material 12 include silicone gels such as ELASTOSIL (registered trademark) RT601 manufactured by Asahi Kasei Wacker Silicone Co., Ltd. and DY35-700A / B manufactured by Toray Dow Corning Co., Ltd. As the gel raw material 12, urethane rubber such as EF243 manufactured by Daiichi Kogyo Seiyaku Co., Ltd. or KU7008 manufactured by Hitachi Chemical Co., Ltd. can be used.
Further, the gel raw material 12 under investigation includes a mixture of an addition reaction type silicone rubber raw material and silicone oil. In this case, the mixing ratio is preferably about 1 for silicone rubber and about 9 for silicone oil.

Next, the raw material supply tool 100 will be described. FIG. 2 is a perspective view, partly broken, showing a schematic configuration of the raw material supply tool 100. As shown in FIG. 2, the raw material supply tool 100 includes a tank part 110 that stores an uncured gel raw material 12, and an injection part 120 that injects and supplies the gel raw material 12 in the tank part 110 into the tub tube 8. The upper part of the tank part 110 is opened, and the gel raw material 12 in which the main agent and the curing agent are stirred is injected into the tank part 110 from this part.
The injection part 120 has an injection port 121 at its lower end surface (see FIG. 3). The gel material 12 flows out from the inlet 121. The injection unit 120 has an open / close valve (not shown) that opens and closes the injection port 121. Further, a screen mesh 130 is arranged in the flow path of the gel raw material 12 on the upstream side of the inlet 121. As the gel raw material 12 passes through the screen mesh 130, the gel raw material 12 flows out from the inlet 121 in a filtered state.

  FIG. 3 is a top view showing the relationship between the injection part 120 and the inner peripheral surface 81 of the soot tube 8 when the raw material supply tool 100 is installed at the upper end of the soot tube 8. As shown in FIG. 3, the injection part 120 is formed such that a part of its outer shape is along the inner peripheral surface 81 of the soot tube 8. Similarly, the shape of the injection port 121 is also formed along the inner peripheral surface 81 of the soot tube 8. Due to such a shape, the gel raw material 12 that has passed through the injection port 121 is injected into the soot tube 8 along the inner peripheral surface 81 of the soot tube 8.

Next, a method for assembling the power cable terminal connection portion 1 of this embodiment will be described.
First, the end of the power cable 2 is cut off to expose the conductor 5, and the conductor lead bar 7 is connected to the conductor 5 by compression or the like. Next, the lower metal fitting 10 is attached to the power cable 2, and then the rubber block 6 is attached to a predetermined position (cable core). When the alignment of the rubber block 6 is completed, the power cable 2 is inserted into the soot tube 8 or the soot tube 8 is placed on the power cable 2, and the lower metal fitting 10 is attached to the soot tube 8. After this attachment, the gel stopper 13 is formed while performing anticorrosion treatment between the cable holding tube 11 of the lower metal fitting 10 and the power cable 2.

  And as shown in FIG. 3, the position of the raw material supply tool 100 is fixed along the injection | pouring part 120 of the raw material supply tool 100 to the internal peripheral surface 81 of the soot pipe 8. As shown in FIG. Then, as shown to Fig.4 (a), what stir-mixed the main ingredient and the hardening | curing agent which are gel raw materials with a hand mixer etc. in the tank part 110 of the raw material supply tool 100 is inject | poured.

When a certain amount of the gel raw material 12 is stored in the tank part 110, the inlet 121 is opened by the on-off valve. Thereby, the gel raw material 12 is filtered by the screen mesh 130 and flows out from the inlet 121 as shown in FIG. At this time, the gel raw material 12 falls from the upper end portion of the soot tube 8 along the inner peripheral surface 81 and is injected into the soot tube 8.
As shown in FIG.4 (c), when the gel raw material 12 is filled in the soot pipe 8, the on-off valve is closed and the injection of the gel raw material 12 is stopped.

  And the upper metal fitting 9 is attached to the soot pipe 8 as shown in FIG.4 (d). Thereby, the assembly of the power cable terminal connection portion 1 is completed.

  As described above, according to the present embodiment, the gel raw material 12 is injected from the upper end portion of the soot tube 8 into the soot tube 8 by the raw material supply tool 100, so that the material supplying tool 100 can be disposed above the soot tube 8. Therefore, the space required for the assembly work of the power cable terminal connection portion 1 can be reduced accordingly. Even if a dedicated injection device is omitted, the gel raw material 12 can be injected by a simple method of pouring from the upper part of the tub tube 8.

  Moreover, by filtering the gel raw material 12 with the screen mesh 130, the air and foreign matter in the gel raw material 12 can be largely removed before being injected into the tub tube 8, and the factors that lower the insulation performance after curing are suppressed. be able to.

  Moreover, since the gel raw material 12 that has passed through the injection port 121 is injected into the tub tube 8 while spreading thinly along the inner peripheral surface 81 of the tub tube 8, the gel raw material 12 has a large surface area along the inner peripheral surface 81. Become. Thereby, the air remaining inside the gel raw material 12 is easily discharged. Moreover, since the gel raw material 12 falls along the inner peripheral surface 81 of the soot tube 8, the falling speed of the gel raw material 12 can be slowed by the friction, and air is entrained in the gel raw material 12 by the impact of the drop. Can be prevented. Moreover, the state in which the remaining air is easily discharged can be maintained as long as possible. Therefore, the air in the gel raw material 12 can be removed more reliably.

(Embodiment 2)
In the first embodiment, the case where the gel raw material 12 is injected into the vertical pipe 8 along the inner peripheral surface 81 of the vertical pipe 8 has been described as an example. 8 may be injected. In this case, as shown in FIGS. 5 and 6, the injection part 120 a and the injection port 121 a of the raw material supply tool 100 </ b> A are formed in a shape along the outer peripheral surface 21 of the power cable 2. Then, the injection portion 120a of the raw material supply tool 100A is placed along the outer peripheral surface 21 of the power cable 2, the position of the raw material supply tool 100A is fixed, and the gel raw material 12 flows from the injection port 121a. Thereby, the gel raw material 12 is inject | poured in the soot pipe 8 along the outer peripheral surface 21 of the electric power cable 2. FIG.
Note that, as shown in FIG. 7, even if the injection part 120 b and the injection port (not shown) of the raw material supply tool 100 </ b> B are formed in a shape along the outer peripheral surface of the conductor pull-out bar 7, the gel raw material 12 remains on the outer peripheral surface of the power cable 2. It is injected into the tub tube 8 along the line 21.

(Embodiment 3)
In the first embodiment, the gel material 12 is injected with the inside of the tub tube 8 open, but the gel material 12 can also be injected with the tub tube 8 sealed. In this case, it is preferable that the pressure in the soot tube 8 is lower than the external pressure at the time of injection. Hereinafter, a specific description will be given with reference to FIG.

  First, the end of the power cable 2 is cut off to expose the conductor 5, and the conductor lead bar 7 is connected to the conductor 5 by compression or the like. Next, the lower metal fitting 10 is attached to the power cable 2, and then the rubber block 6 is attached to a predetermined position (cable core). When the alignment of the rubber block 6 is completed, the power cable 2 is inserted into the soot tube 8 or the soot tube 8 is placed on the power cable 2, and the lower metal fitting 10 is attached to the soot tube 8. Thereafter, the gel stopper 13 is formed while performing anticorrosion treatment between the cable holding tube 11 of the lower metal fitting 10 and the power cable 2.

  Thereafter, the upper metal fitting 9 c is attached to the soot tube 8. As shown in FIG. 8A, the upper metal fitting 9c has two communication ports 91 and 92 that allow the internal space of the soot tube 8 to communicate with the outside. After the upper metal fitting 9 c is attached, the injection part 120 of the raw material supply tool 100 is connected to one communication port 91, and the pump 200 as an atmospheric pressure adjusting device is connected to the other communication port 92. By this connection, the inner space of the soot tube 8 is sealed.

  After sealing, the pump 200 is operated to make the pressure inside the soot tube 8 lower than the outside pressure. In addition, although the pump 200 is illustrated here as an atmospheric pressure adjusting device, a compressor etc. can also be used as an atmospheric pressure adjusting device.

  When the pressure inside the soot tube 8 becomes lower than the outside air pressure, as shown in FIG. 8B, when the on-off valve is opened, the gel raw material 12 in the tank part 110 flows out from the injection part 120 and enters the inside of the soot pipe 8. Injected.

  As shown in FIG. 8 (c), when the gel raw material 12 is filled up to a predetermined position and filled in the soot tube 8, the on-off valve is closed to stop the injection of the gel raw material 12.

  Then, as shown in FIG. 8D, the raw material supply tool 100 and the pump 200 are removed from the upper metal fitting 9c, and the lids 93 and 94 are attached to the communication ports 91 and 92, and the pressure state in the soot tube 8 is maintained. Seal. When the gel raw material 12 is cured after a predetermined time has elapsed, the assembly of the power cable terminal connection portion is completed.

As described above, when the pressure in the tub tube 8 is made lower than the external pressure at the time of injecting the gel raw material 12, the discharge of the air mixed in the gel raw material 12 can be accelerated.
Furthermore, since the injection speed of the gel material 12 is increased by the pressure difference, the operation of injecting the gel material 12 can be completed quickly. Thereby, the hardening time of the gel raw material 12 can be taken for a long time, and it is easy to ensure the time to wait until the air in the gel raw material 12 with which the soot tube 8 was filled is discharged | emitted.

(Embodiment 4)
Although the assembly method according to the present invention has been described by exemplifying the so-called “epoch seat-less” type power cable terminal connection portion 1 in which the rubber block 6 is exposed in the first embodiment, the power cable terminal connection portion having an epoxy seat is described. It is also possible to apply the assembly method according to the present invention.

Hereinafter, the power cable terminal connection portion 1D having an epoxy seat will be described with reference to FIG. In FIG. 9, 2d is a power cable insulated with rubber or plastic. The power cable 2 is stripped, and the external semiconductive layer 3d, the insulating layer 4d, and the conductor 5d are sequentially exposed. 6d is a rubber block attached from the outer semiconductive layer 3d of the power cable 2 to the insulating layer 4d. 7d is a conductor lead bar compressed and connected to the conductor 5d, 8d is a porcelain pipe made of porcelain, 9d is an upper metal fitting of the pipe 8d, 10d is a lower metal fitting, 11d is a cable holding pipe integrated with the lower metal fitting 10d, and 13d is a gel. This is a gel stopper that prevents the raw material 12 from flowing out.
14d is an epoxy seat that covers the rubber block 6d, and 15d is a rubber compression device that presses and holds the rubber block 6d against the cable core by pressing the epoxy seat 14d against the rubber block 6d.

DESCRIPTION OF SYMBOLS 1 Power cable termination | terminus connection part 2 Power cable 3 External semiconductive layer 4 Insulating layer 5 Conductor 6 Rubber block 7 Conductor extraction rod 8 Fence pipe 9 Upper metal fitting 10 Lower metal fitting 11 Cable holding tube 12 Gel raw material 12a Gel 13 Gel stop part 21 Outer peripheral surface 61 Semiconductive rubber part 62 Insulating rubber part 81 Inner peripheral surface 91 Communication port 92 Communication port 100 Raw material supply tool 110 Tank unit 120 Injection unit 121 Inlet port 130 Screen mesh 200 Pump (atmospheric pressure adjusting device)

Claims (4)

In the assembling method of the power cable terminal connection portion in which the gel-like insulating filler is filled in the soot tube into which the end portion of the power cable is inserted,
When injecting the gel raw material to be the insulating filler from the upper part of the soot pipe of the power cable terminal connection portion into the soot pipe, the gel raw material is passed through the raw material supply tool provided on the top of the soot pipe. Injected into the fistula,
The raw material supply tool has a tank part in which the gel raw material is stored, and an inlet for injecting the gel raw material in the tank part into the soot tube,
The method for assembling a power cable terminal connecting portion , wherein the inlet is formed in a shape along an inner peripheral surface of the soot tube . In the assembling method of the power cable terminal connection portion in which the gel-like insulating filler is filled in the soot tube into which the end portion of the power cable is inserted,
  When injecting the gel raw material to be the insulating filler from the upper part of the soot pipe of the power cable terminal connection portion into the soot pipe, the gel raw material is passed through the raw material supply tool provided on the top of the soot pipe. Injected into the fistula,
  The raw material supply tool has an inlet for injecting the gel raw material into the soot tube,
  The method of assembling a power cable terminal connecting portion, wherein the injection port is formed in a shape along an outer peripheral surface of a power cable disposed in the vertical pipe. In the assembly method of the termination connection part of the power cable according to claim 1 or 2 ,
A method for assembling a power cable terminal connecting portion, wherein a screen mesh is disposed on the raw material supply tool, and the gel raw material is filtered by the screen mesh at an upper portion of the soot tube. In the assembly method of the electric power cable termination | terminus connection part as described in any one of Claims 1-3 ,
A method of assembling a power cable terminal connecting portion, wherein the inside of the soot tube is sealed at the time of injecting the gel raw material, and the pressure inside the soot tube is made lower than the external pressure.

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