JP6097728B2 - Power cable connecting apparatus and power cable connecting method - Google Patents

Description

  The present invention relates to a power cable connecting device and a power cable connecting method.

2. Description of the Related Art Conventionally, as a connection portion of a power cable, a structure is known in which cable conductors that are exposed by stepping off ends of a power cable are connected to each other, and an insulating cylinder is attached to the conductor connection portion.
The conductor of the power cable is connected at the construction site, and the method of compressing the cylinder for connecting the power cable is most often used for this. For example, as shown in Patent Document 1, an insulating cylinder with a diameter-enlarged support cylinder is used in which a room-temperature-shrinkable insulating cylinder (molded product of silicone rubber or EP rubber) is expanded and supported by a diameter-enlarged support cylinder. .
As the construction procedure, after inserting the power cable into the insulating cylinder with the expanded support cylinder and connecting the conductors of the power cables, the conductor connection part is arranged at the center of the insulated cylinder with the expanded support cylinder The insulating cylinder with the expanded diameter support cylinder is moved, and the expanded diameter support cylinder is removed, whereby the diameter of the insulated cylinder is reduced and tightly fixed to the outer periphery of the power cable including the conductor connecting portion.
After mounting the insulating cylinder as described above, an electrical shielding process using a metal layer, a protective tube assembly for enhancing mechanical strength, and a grounding wire drawing process from the protective tube were performed.

JP 2001-37065 A

However, the conventional technique has the following problems.
First, the insulation cylinder attached to the conductor connection part between the power cables has an inner diameter so that the power cable can be inserted into the hollow part of the insulation cylinder and moved along the power cable during assembly at the construction site. The diameter is expanded until approximately twice or more. The outer diameter changes approximately 1.5 times or more when the expanded diameter is maintained and when the reduced diameter is mounted.
For this reason, the electrical shielding process and the protective tube assembly can be performed only after the insulating cylinder is attached to the power cable, and it takes field construction time to perform these operations.
In addition, if construction is performed in the order of installation of the insulating cylinder, electrical shielding treatment, and protective tube assembly, a gap will inevitably remain between the electrical shielding layer and the inner surface of the protective tube. Since this gap greatly contributes to the temperature rise during power cable operation, it is preferable not to leave a gap. Therefore, the work of injecting a waterproof compound or the like into the gap after assembling the protective tube is also required.
In addition, since the insulation cylinder is installed on the conductor connection part of the power cable in the field, it is necessary to set the dimensions of each part in consideration of assembly errors during installation (mounting dimension deviation), and the insulation cylinder length is also It is longer than the ideal design dimension.

The present invention has been made in view of the above-described problems in the prior art, and can reduce the work amount and work time at the connection construction site between power cables, and the productivity and reliability of the power cable connection portion. It is an object of the present invention to provide a power cable connecting device and a power cable connecting method capable of improving the power.

The invention according to claim 1 for solving the above-described problems is an insulating cylinder attached to a conductor connecting portion connecting conductors of a power cable;
An electrical shielding layer applied to the outer peripheral side of the insulating cylinder;
A protective tube provided on the outer peripheral side of the electrical shielding layer,
The insulating cylinder receives a connection end of one power cable inserted from one end opening of a hollow portion of the insulating cylinder, and receives a connection end of another power cable inserted from the other end opening. The conductors of the one power cable and the other power cable are configured to be connectable within the hollow portion of the insulating cylinder ,
An insertion jig is provided, and the distal end portion of the insertion jig is inserted into a receiving portion that accepts the connection end formed in the hollow portion, and the connection end when the power cable is connected to the receiving portion. It is a power cable connecting device in which the insertion jig is detachably held from the receiving portion for insertion .

Invention 請 Motomeko 2 described has two connecting portions is disposed in the hollow portion of the electric connection conductor for connecting the conductors between the power cables the insulating cylinder, one connection of the electrical connecting conductors The connection terminal mounted on the conductor tip of the connection end of the one power cable is disposed toward one end opening of the hollow portion of the insulating cylinder, and the other connection is the other The power cable connecting device according to claim 1, wherein the power cable connecting device can be connected to a connection terminal attached to a conductor tip of a connection end of the power cable and is arranged toward the other end opening of the hollow portion of the insulating cylinder. It is.

A third aspect of the present invention is the power cable connecting device according to the first or second aspect , wherein a buffer material is installed between the electrical shielding layer and the protective tube.

Invention of Claim 4 is an electric power cable connection apparatus as described in any one of Claims 1-3 in which the anticorrosion layer was given to the outer peripheral side of the said protective tube.

The invention according to claim 5 is an insulating cylinder attached to a conductor connecting portion connecting conductors of a power cable,
An electrical shielding layer applied to the outer peripheral side of the insulating cylinder;
A power cable connection method for connecting power cables to each other using a power cable connection device provided with a protective tube provided on the outer peripheral side of the electrical shielding layer,
After the electrical shielding layer and the protective tube are applied to the insulating cylinder,
The connection end of one power cable is inserted from one end opening of the hollow portion of the insulating cylinder, the connection end of another power cable is inserted from the other end opening, and the one power cable and the other power cable are inserted. This is a power cable connection method in which the conductors are connected in the hollow portion of the insulating cylinder.

According to the present invention, since an electrical shielding layer, a protective tube, etc. are already provided for the insulating cylinders before the connection between the power cables, these parts can be produced in the factory, and therefore the connection construction between the power cables is performed. It is possible to reduce the amount of work and time on site.
In addition, it is possible to improve productivity, improve quality, and make uniform through factory production, and since conductor connection is performed within the insulation cylinder, it is easy to regulate the conductor connection position with respect to the insulation cylinder and pursue ideal design. Further, since there is no support for greatly expanding the diameter of the insulating cylinder for inserting the conventional power cable, the elastic characteristics of the insulating cylinder are hardly deteriorated.
Through the above-mentioned factory production and work at the connection construction site between the power cables, the productivity and reliability of the power cable connecting portion can be improved.

It is an axial sectional view of a power cable connection part in one embodiment of the present invention. It is an axial sectional view of a power cable connecting device concerning one embodiment of the present invention. It is the figure which showed the part by which the insulating cylinder and protection tube of the power cable connecting device which concern on one Embodiment of this invention are arrange | positioned with a frame. FIG. 4 shows an outline of a structure in which a protective tube having an inner flange structure at both ends is applied to a portion corresponding to the inside of the frame shown in FIG. 3. It is a side view of the site | part containing the connection edge part of an electric power cable. The state which provided the slip-on connection terminal with respect to the structure shown in FIG. 5 is shown.

  An embodiment of the present invention will be described below with reference to the drawings. The following is one embodiment of the present invention and does not limit the present invention.

FIG. 1 shows an axial cross-sectional view of a power cable connecting portion in one embodiment of the present invention. FIG. 2 shows an axial cross-sectional view of the power cable connecting device according to one embodiment of the present invention. That is, FIG. 1 shows a completed form of a power cable connecting portion at a connection construction site between power cables, and FIG. 2 shows a form of the power cable connecting apparatus 1 produced in a factory. The power cable connecting device 1 shown in FIG. 2 is supplied to and applied to the connection construction site, whereby the power cable connecting portion shown in FIG. 1 is configured.
As shown in FIG. 1, the power cables 30 and 30 are connected to each other.

(1) First, I will explain along the production process in the factory.
(A) First, the rubber block insulating cylinder 10 is molded as in the prior art.
(B) Next, the electrical connection conductor 11 having female contact portions 11a, 11b for multi-contact at both ends is installed at the axial center portion in the hollow portion of the rubber block insulating cylinder 10. The electrical connection conductor 11 electrically connects the conductors of the power cables 30 and 30 inserted into the rubber block insulating cylinder 10.
(C) Next, on the outer peripheral side of the rubber block insulating cylinder 10, an electrical shielding layer 12 similar to that performed at a conventional construction site is applied. The electrical shield layer 12 is required to be connected with a current capacity equivalent to that of the electrical shield layer 31 of the power cable 30 (shield bond). Specifically, the electrical shield layer 31 of the power cable 30 Copper braided wires with the same cross-sectional area or more are applied. A crimp terminal 13 is attached to the end of the electrical shielding layer 12 so that it can be connected to the electrical shielding layer 31 of the power cable 30 in a short time at the construction site.

(D) Next, a buffer material 15 (compound, silicone gel, non-ferrous wool, etc.) is installed between the electrical shielding layer 12 and the protective tube 14 (14a, 14b). In the present embodiment, the entire protective tube 14 is configured by connecting a relatively long protective tube 14a and a relatively short protective tube 14b in the axial direction.
In the case of a buffer material that is liquid before curing, such as a compound or a silicone gel, the buffer material 15 is placed in the protective tube 14a after the rubber block insulating cylinder 10 is disposed, and then joined to the protective tube 14b. The buffer material 15 is injected from the gap on the side, and after the buffer material 15 is cured, the protective tube 14b is joined to the protective tube 14a and the lid is closed.
The compound may be butadiene rubber or the like conventionally used for filling the protective tube in the connection portion, and there is no special requirement for application to the present invention. Silicone gel is a silicone oil blended with a curing agent. “Soft and small load due to low crosslink density, easily deforms under pressure”, “Low elastic modulus to relieve stress due to thermal expansion”, “ Commercially available products (such as Shin-Etsu Silicone KE-1052A / B and Toray 3-4118Gel A & B) are available.
On the other hand, in the case of a deformable solid such as non-ferrous wool, the cushioning material 15 is wound around the rubber block insulating cylinder 10 provided with the electrical shielding layer 12 so that the outer diameter is slightly larger than the inner diameter of the protective tube 14a. By inserting the protective tube 14a into the protective tube 14a, sufficient mechanical and heat transfer adhesion is secured among the rubber block insulating cylinder 10 (electrical shielding layer 12), the buffer material 15, and the protective tube 14a. can do.
Due to the deformation of the cushioning material 15, the slight deformation of the rubber block insulating cylinder 10 at the time of cable insertion is absorbed (the outer diameter is increased and the length is reduced), and the rubber block insulation generated during the construction of the power cable is absorbed. It can cope with slight fluctuations in the outer diameter of the cylinder 10.
As described above, a material having a deformation function that can withstand the mechanical behavior at the time of insertion of the cable into the rubber block insulating cylinder 10 and operation is applied as the buffer material 15. In addition, between the rubber block insulating cylinder 10 and the protective tube 14, the heat generation of the cable conductor cannot be efficiently radiated to the outer peripheral side of the power cable connection portion in a state close to a heat insulation state such as air. Cause excessive temperature rise. Therefore, the shock absorbing material 15 is required to sufficiently conduct heat between the rubber block insulating cylinder 10 and the protective tube 14 during operation. That is, as the buffer material 15, a material having a heat conduction function that can withstand the thermal behavior during operation is applied in addition to the above deformation function.

(E) The protective tube 14 is narrowed so that both ends in the longitudinal direction are close to the outer diameter of the power cable 30. The protective tube 14 is a two-part product (protective tube 14a and protective tube 14b), and the rubber block insulating cylinder 10 is formed by connecting the protective tube 14a and the protective tube 14b together with the installation of the buffer material 15 as described above. And the protective tube 14 are integrated.
The material of the protective tube 14 is a metal of aluminum or copper, and the protective tube 14 ensures the water shielding performance and the trauma resistant mechanical strength of the power cable connecting portion. When the cross-sectional area of the metal part of the protective tube 14 is sufficiently secured, the protective tube 14 can be substituted for this function by omitting the shielding bond by the electrical shielding layer 12.
The shape of the protective tube 14 is not a tapered shape (aperture shape) as shown in FIGS. 1 to 3 because the outer diameter of the central portion changes from a thick portion to the same diameter as the power cable 30 at the end. Further, the end portion can be made to have a structure close to a right angle by a flange structure or the like as shown in FIG. In this case, there are advantages that the entire length of the protective tube can be shortened and that the end portion of the rubber block insulating cylinder 10 can be easily visually confirmed during assembly at the power cable connection construction site. FIG. 4 shows an outline of the structure in which the protective tube 14F having both inner flange structures is applied to the portion corresponding to the inside of the frame A shown in FIG.

(F) After installing the electrical connection conductor 11, when installing the cushioning material 15 and assembling the protective tube 14, an insertion jig having an outer shape corresponding to the connection end 30a of the power cable 30 at the distal end 40a. As shown in FIG. 2, the tools 40 and 40 are inserted into the rubber block insulating cylinder 10, and the rubber block insulating cylinder 10 is corrected so as to be in the connection part assembly final form (shape dimension at the time of use).

(G) Further, the anticorrosion layers 16a and 16b are formed on the outer peripheral side of the protective tube. As shown in FIG. 2, the power cable connecting device 1 is shipped in a state where the insertion jigs 40 are inserted into the rubber block insulating cylinder 10.

(2) Next, description will be made while following the work process at the power cable connection construction site. (A) First, the connection end 30a of the power cable 30 is connected using a conventional rubber block insulating cylinder. The same processing as that of the unit is performed. Specifically, as shown in FIG. 5, each layer such as a conductor, an insulator, an external semiconductive layer, a shielding layer, a water shielding layer, and an anticorrosion layer is finished in a stepped shape from the power cable center layer side.

(B) Next, as shown in FIG. 6, the conductor 32 of the power cable 30 is inserted into a male slip-on connection terminal 33 having a multi-contact band, and is crimped (compression connection using a hydraulic die, etc.).
(C) Next, one side of the insertion jig 40 (here, the right side in FIG. 2) is pulled out and removed from the rubber block insulating cylinder 10 of the power cable connecting apparatus 1 assembled in the factory of FIG. The connection end 30a of the power cable 30 finished in (b) is inserted there.
Subsequently, the same operation is performed on the left side of FIG. 2 so that the power cables 30 are attached to both ends of the rubber block insulating cylinder 10 as shown in FIG. By this step, the slip-on connection terminal 33 that has been crimped to the tip of the conductor 32 of the power cable 30 and the electrical connection conductor 11 that has been installed at the center of the rubber block insulating cylinder contact with a predetermined size, A rated current can be passed between the conductor 32 of one power cable 30 and the conductor 32 of another power cable 30.

As described above, in the power cable connecting apparatus 1, the insulating cylinder 10 receives the connection end 30a of the one power cable 30 inserted from the one end opening m1 of the hollow portion of the insulating cylinder 10, and from the other end opening m2. The connection end 30a of the other power cable 30 to be inserted is received, and the conductors 32, 32 of the one power cable 30 and the other power cable 30 can be connected in the hollow portion of the insulating cylinder 10. It is a thing.
When the connection end 30a is inserted into the insulating cylinder 10, it is inserted with friction between the outer peripheral surface of the connection end 30a and the inner peripheral surface of the insulating cylinder 10, and the connection end 30a is caused by friction fitting. Is preferably fixed to the insulating cylinder 10.
Further, in the power cable connecting apparatus 1, one connecting portion 11 a of the electric connecting conductor 11 can be connected to the connecting terminal 33 attached to the conductor tip of the connecting end portion 30 a of the one power cable 30 and is an insulating cylinder. 10 is arranged toward one end opening m1 of the hollow portion, and the other connection portion 11b can be connected to the connection terminal 33 attached to the conductor tip of the connection end portion 30a of the other power cable 30 and is an insulating cylinder. It is arranged toward the other end opening m2 of the hollow portion of the body 10.
Further, the power cable connecting apparatus 1 is provided with an insertion jig 40 having an outer shape corresponding to the connection end portion 30a of the power cable 30 at the distal end portion 40a. The distal end portion 40 a of the insertion jig 40 has an outer shape corresponding to at least a portion inserted into the insulating cylinder 10 in the connection end portion 30 a of the power cable 30, and also has a portion corresponding to the slip-on connection terminal 33. It is preferable.
Moreover, the front-end | tip part 40a of the insertion jig 40 is inserted in the receiving part 10a which accepts the connection end part 30a formed in the hollow part of the insulation cylinder 10, and is connected to the receiving part 10a of the connection end part 30a at the time of power cable connection. The insertion jig 40 is held so as to be removable from the receiving portion 10a.

Also in the power cable connecting portion according to the present embodiment, the close contact between the insulator surface of the power cable 30 and the inner surface of the rubber block insulating cylinder 10 is one of technically important matters. This is a conventional rubber block insulating cylinder. Similar to the connecting portion using the rubber block insulating cylinder, the inner diameter of the rubber block insulating cylinder is made smaller than the outer diameter of the insulator of the power cable 30, whereby the adhesion effect due to the contraction force of the rubber block insulating cylinder 10 can be obtained.
The adhesion force (surface pressure) obtained at the interface is affected by the difference in diameter between the two, but in the present invention, the rubber block insulating cylinder 10 is made to prevent pre-expansion of the rubber block insulating cylinder 10. Since the phenomena such as permanent deformation and stress relaxation of the rubber material to be formed do not occur so much, there is an advantage that high adhesion can be obtained and maintained even if the difference in diameter between the two is reduced.

Here, the application example to a 66 kV class power cable is disclosed regarding the outer diameter of the rubber block insulation cylinder 10. FIG. Table 1 shows the time points at the time of molding the rubber block insulating cylinder 10 by the conventional pre-expansion method and the insertion method of the present invention (A), at the time of factory shipment (B), and after mounting on the power cable (C). The outer diameter at is posted. Two examples are shown for the present invention.
As shown in Table 1, the outer diameter of the rubber block insulating cylinder 10 at the time of molding (A) is common at Φ100 mm in the conventional pre-expansion method and the insertion method of the present invention.
As shown in Table 1, in the insertion method of the present invention, the amount of change in the outer diameter of the rubber block insulating cylinder 10 is small compared to the conventional pre-diameter method (particularly the difference between B and C in Table 1). It can be seen that the factory assembly shipment described in (1) above is possible.

(D) Now, after the power cable 30 is inserted into the rubber block insulating cylinder 10, the electrical shielding layer 12 and the electrical shielding layer 31 of the power cable 30 are connected by the crimp terminal 13.
(E) Finally, the end portion of the protective tube 14 and the anticorrosion layer 34 of the power cable 30 are connected by the heat-shrinkable tube 17 and the anticorrosion tape 18 to ensure water shielding performance and anticorrosion performance (the end of the power cable connection portion). Anticorrosion treatment). For this, the same technique as that of the conventional power cable connecting portion can be applied.

(3) According to the power cable connecting device of the above embodiment, the following effects are obtained.
(A) At the power cable connection construction site, the connection end 30a of one power cable 30 is inserted from one end opening m1 to the center of the rubber block insulating cylinder 10, and the connection end 30a of another power cable 30 is inserted. Since the method of inserting from the other end opening m2 to the center of the rubber block insulating cylinder 10 is adopted, the inner diameter of the rubber block insulating cylinder 10 is increased so that the work of inserting the power cable is facilitated as in the prior art. There is no need to do it. There is no significant change in the outer diameter of the rubber block insulating cylinder 10 before and after being attached to the power cable 30, and a protective tube assembly for electrical shielding treatment and mechanical strength enhancement can be implemented in advance at the factory assembly. become. As a result, the amount of work and the work time at the power cable connection construction site are shortened.
(B) As described in (a), since the outer diameter of the rubber block insulating cylinder 10 does not change greatly before and after being attached to the power cable 30, permanent deformation and stress of the rubber block insulating cylinder due to the pre-expansion history. Since the degree of occurrence of relaxation is smaller than in the past, the rubber block mounting ratio ([Outer diameter attached to power cable (C in Table 1)]] [Rule outer diameter of rubber block insulating cylinder (Table Even if the ratio of 1) to A)] is reduced, a sufficient surface pressure can be secured between the power cable 30 and the rubber block insulating cylinder 10. Alternatively, when a conventional mounting rate is applied, a higher surface pressure can be obtained more stably.
(C) Since the electrical shielding layer 12 and the protective tube 14 are assembled at the factory, it is not necessary to inject a compound to fill a gap generated at the power cable connection construction site. This also leads to a reduction in the amount of work and work time at the construction site of the power cable connection.
(D) Since the position of the tip end of the connection end 30a of the power cable 30 is regulated at the central portion where the electrical connection conductor 11 is installed in the rubber block insulating cylinder 10, the assembly error at the power cable connection construction site ( The displacement of the mounting dimension) can be suppressed as compared with the conventional method described above, and an ideal design can be pursued by setting the axial dimensional tolerance of each part of the power cable connecting device 1 to be small. Therefore, waste of material can be eliminated and the power cable connecting portion can be configured more compactly.

DESCRIPTION OF SYMBOLS 1 Power cable connection apparatus 10 Rubber block insulation cylinder 11 Electrical connection conductor 11a Connection part 11b Connection part 12 Electrical shielding layer 13 Crimp terminal 14 Protection tube 15 Buffer material 16a, 16b Anticorrosion layer 17 Heat shrinkable tube 18 Anticorrosion tape 30 Power cable 30a connection end 32 conductor 33 slip-on connection terminal 34 anticorrosion layer 40 insertion jig 40a tip end m1 one end opening m2 other end opening

Claims (5)

An insulating cylinder attached to a conductor connecting portion connecting the conductors of the power cable;
An electrical shielding layer applied to the outer peripheral side of the insulating cylinder;
A protective tube provided on the outer peripheral side of the electrical shielding layer,
The insulating cylinder receives a connection end of one power cable inserted from one end opening of a hollow portion of the insulating cylinder, and receives a connection end of another power cable inserted from the other end opening. The conductors of the one power cable and the other power cable are configured to be connectable within the hollow portion of the insulating cylinder ,
An insertion jig is provided, and the distal end portion of the insertion jig is inserted into a receiving portion that accepts the connection end formed in the hollow portion, and the connection end when the power cable is connected to the receiving portion. An electric power cable connecting device in which the insertion jig is detachably held from the receiving portion for insertion .   An electric connecting conductor having two connecting portions and connecting the conductors of the power cable is installed in the hollow portion of the insulating cylinder, and one connecting portion of the electric connecting conductor is a connecting end of the one power cable. It is connectable with the connection terminal attached to the conductor tip of the part, and is arranged toward one end opening of the hollow part of the insulating cylinder, and the other connection part is a conductor of the connection end part of the other power cable. The power cable connecting device according to claim 1, wherein the power cable connecting device is connectable to a connection terminal attached to a distal end portion and is arranged toward the other end opening of the hollow portion of the insulating cylinder. The power cable connecting device according to claim 1 or 2 , wherein a buffer material is installed between the electrical shielding layer and the protective tube. The power cable connecting device according to any one of claims 1 to 3 , wherein an anticorrosion layer is provided on an outer peripheral side of the protective tube. An insulating cylinder attached to a conductor connecting portion connecting the conductors of the power cable;
An electrical shielding layer applied to the outer peripheral side of the insulating cylinder;
A power cable connection method for connecting power cables to each other using a power cable connection device provided with a protective tube provided on the outer peripheral side of the electrical shielding layer,
After the electrical shielding layer and the protective tube are applied to the insulating cylinder,
The connection end of one power cable is inserted from one end opening of the hollow portion of the insulating cylinder, the connection end of another power cable is inserted from the other end opening, and the one power cable and the other power cable are inserted. A power cable connection method for connecting the conductors of each other in the hollow portion of the insulating cylinder.

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