JP2019193390A - Composite bushing and termination connection section - Google Patents

Abstract

To provide a composite bushing capable of reducing a bubble trace generated on a surface of an outer cover section during molding.SOLUTION: A composite bushing comprises: an insulating cylinder having a hollow space in which a termination section of a power cable is housed; an outer cover section molded by a polymer material on an outer peripheral surface of the insulating cylinder; a lower electrode provided at a lower end section of the insulating cylinder; and a lower metal fitting having a flange section formed at a lower end of the lower electrode and opposed to a lower end face of the insulating cylinder. Between the insulating cylinder and the flange section, a gap opened toward an outer peripheral side is provided. The outer cover section is formed to astride the insulating cylinder and the lower metal fitting so as to cover at least a part of an outer peripheral surface of the flange section, and a polymer material of the outer cover section is penetrated into the gap.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a composite steel pipe and a terminal connection part.

  At the termination of the power cable, a termination connection for connecting to an overhead wire or other power equipment (for example, a switchgear (breaker) or a transformer) is provided. The terminal connection part of the power cable is provided with a soot tube that accommodates the terminal part of the power cable.

  As a soot tube used for a terminal connection portion, a composite soot tube (sometimes called a polymer soot tube) in which an outer casing made of a polymer material such as silicone rubber is molded on the outer peripheral surface of an insulating tube made of an insulating resin such as an epoxy resin. ) Patent Document 1 discloses a polymer sleeve (composite) including an insulating cylinder, a polymer covering (outer part) provided on the outer periphery of the insulating cylinder, and a shielding electrode (lower electrode) formed integrally with the insulating cylinder.碍 管) is described. In the composite soot tube of Patent Document 1, a shielding electrode is provided on the rear end (lower end) side of the insulating cylinder, the shielding electrode is embedded in the insulating cylinder, and a flange portion is formed at the lower end of the shielding electrode.

JP 2014-45553 A

  In the above-described composite soot tube, crater-like bubble marks may be formed on the surface of the jacket portion molded on the outer peripheral surface of the insulating cylinder during manufacture. If there is a bubble mark on the surface of the jacket part, the appearance is impaired. Therefore, it is desirable to reduce the bubble mark generated on the surface of the jacket part during molding.

  Therefore, an object of the present disclosure is to provide a composite soot tube that can reduce bubble marks generated on the surface of the jacket portion during molding. Another object of the present invention is to provide a terminal connection portion including the composite soot tube.

The composite steel pipe according to the present disclosure is
An insulating cylinder having a hollow space in which the terminal portion of the power cable is accommodated;
A jacket portion molded with a polymer material on the outer peripheral surface of the insulating cylinder;
A lower electrode provided at a lower end portion of the insulating cylinder, and a lower metal fitting having a flange portion formed at the lower end of the lower electrode and facing the lower end surface of the insulating cylinder,
Between the insulating cylinder and the flange portion, there is a gap opening on the outer peripheral side,
The jacket portion is formed across the insulating cylinder and the lower metal fitting so as to cover at least a part of the outer peripheral surface of the flange portion, and the polymer material of the jacket portion enters the gap.

The termination connection according to the present disclosure is
The composite fistula of the present disclosure is provided.

  The composite soot tube can reduce bubble marks generated on the surface of the jacket portion during molding. The terminal connection part is excellent in the appearance of the outer cover part surface of the composite soot tube.

FIG. 2 is a schematic vertical half sectional view of a composite soot tube according to Embodiment 1. It is a principal part expanded sectional view which expands and shows the part enclosed with the II line | wire of FIG. FIG. 3 is a schematic partial longitudinal sectional view showing a terminal connection portion according to the first embodiment.

[Description of Embodiment of the Present Invention]
In a conventional composite soot tube comprising an insulating cylinder, a jacket portion molded on the outer peripheral surface of the insulating cylinder, and a lower metal fitting having a lower electrode embedded in the insulating cylinder, it is formed at the lower ends of the insulating cylinder and the lower electrode. It is comprised so that it may contact with the flange part. Therefore, almost no gap is formed between the insulating cylinder and the flange portion.

  The composite soot tube is manufactured as follows, for example. First, with the lower metal fitting placed in the mold, an insulating resin is injected to mold the insulating cylinder, and the lower metal fitting is integrally provided at the lower end of the insulating cylinder. At this time, a release agent may be applied to the surface of the lower metal fitting so that the insulating tube and the lower metal fitting are not adhered. In this case, a slight amount of space is provided between the insulating tube and the flange portion of the lower metal fitting. A gap is created. The width of this gap is narrow (for example, less than 1 mm) to such an extent that the polymer material of the jacket part to be molded in the subsequent process does not enter. Thereafter, an insulating cylinder in which the lower metal fitting is integrated is placed in a mold, a polymer material is injected, and a jacket portion is directly molded on the outer peripheral surface of the insulating cylinder to manufacture a composite rod.

  The lower end side of the jacket part may be extended from the insulating cylinder to the flange part of the lower metal part, and the jacket part may be formed so as to cover the outer peripheral surface of the flange part. In this case, bubble marks may be generated on the surface of the jacket portion located at a location straddling the insulating cylinder and the flange portion. The reason why bubble marks occur on the surface of the jacket part is that when the jacket part is molded on the outer peripheral surface of the insulating cylinder, the air existing in the gap between the insulating cylinder and the flange part is thermally expanded. It is thought that bubbles gradually break out of the opening on the outer peripheral side, and the bubbles break through the jacket portion. Even when the mold is evacuated and deaerated before the polymer material is injected, it is difficult to completely remove the air in the gap because the gap is very narrow.

  The present invention has been made in view of the above points. First, embodiments of the present invention will be listed and described.

(1) A composite soot tube according to an embodiment of the present invention is
An insulating cylinder having a hollow space in which the terminal portion of the power cable is accommodated;
A jacket portion molded with a polymer material on the outer peripheral surface of the insulating cylinder;
A lower electrode provided at a lower end portion of the insulating cylinder, and a lower metal fitting having a flange portion formed at the lower end of the lower electrode and facing the lower end surface of the insulating cylinder,
Between the insulating cylinder and the flange portion, there is a gap opening on the outer peripheral side,
The jacket portion is formed across the insulating cylinder and the lower metal fitting so as to cover at least a part of the outer peripheral surface of the flange portion, and the polymer material of the jacket portion enters the gap.

  According to the composite soot tube, since the polymer material of the outer cover portion has entered the gap formed between the insulating cylinder and the flange portion of the lower metal fitting, bubble marks generated on the surface of the outer cover portion during molding Can be reduced. Therefore, the composite soot tube is excellent in appearance because it is difficult for noticeable bubble marks to be generated on the surface of the jacket part during molding of the jacket part.

  The reason why bubble marks can be reduced is presumed as follows. The width of the gap formed between the insulating cylinder and the flange portion is wide enough to allow the polymer material to enter when molding the jacket portion. Therefore, when molding the jacket portion on the outer peripheral surface of the insulating cylinder, the polymer material enters the inside through the opening on the outer peripheral side of the gap, and the air in the gap is expelled. Since the air in the gap is thereby removed, the generation of bubble marks due to the air in the gap can be reduced, so that the bubble marks are formed on the surface of the jacket part located at the location straddling the insulating cylinder and the flange part. Is less likely to occur.

  (2) As one form of the said composite soot pipe, it is mentioned that the opening width of the said clearance gap is 1 mm or more.

  When the opening width of the gap is 1 mm or more, the polymer material easily enters the gap when molding the jacket portion, and the air in the gap is easily removed. Therefore, the bubble trace which generate | occur | produces on the surface of a jacket part can be reduced effectively. For example, the upper limit of the opening width is 10 mm or less. When the opening width of the gap is 10 mm or less, the portion that has entered the gap in the jacket portion when the composite soot tube is subjected to a bending test is not easily damaged by bending strain, and the strength of the jacket portion is easily secured.

  (3) As one form of the said composite soot pipe, it is mentioned that the said clearance gap is formed so that a width | variety may become wide toward an outer peripheral side.

  In this case, since the opening on the outer peripheral side of the gap is wide, the polymer material can easily enter the gap when molding the jacket portion, and the air in the gap can be easily removed. Therefore, the bubble trace which generate | occur | produces on the surface of a jacket part can be reduced effectively.

  (4) As one form of the said composite soot pipe, it is mentioned that the polymer material of the said jacket part is filled into the said whole clearance gap.

  When the entire gap is filled with the polymer material of the jacket part, the polymer material spreads in the gap when the jacket part is molded, and the air in the gap is greatly removed, greatly reducing the occurrence of bubble marks It is possible to eliminate bubble marks generated on the surface of the jacket portion.

(5) The termination connection according to the embodiment of the present invention is
The composite fistula according to any one of (1) to (4) above is provided.

  The terminal connection portion includes the composite soot tube according to the present embodiment, so that no noticeable bubble marks are generated on the surface of the outer shell part of the composite soot tube, and the appearance of the outer shell part surface of the composite soot tube is excellent. .

[Details of the embodiment of the present invention]
Specific examples of the composite steel pipe and the terminal connection portion according to the embodiment of the present invention will be described below with reference to the drawings. The same code | symbol in a figure shows the same name thing. In addition, this invention is not limited to these illustrations, is shown by the claim, and intends that all the changes within the meaning and range equivalent to the claim are included.

  With reference to FIGS. 1-3, the composite soot tube 10 and the termination | terminus connection part 1 which concern on embodiment are demonstrated. FIG. 1 shows a half cross-sectional view of the composite soot tube 10 cut in the axial direction. As shown in FIG. 3, the termination connection portion 1 includes a termination portion of the power cable 100 from which the conductor 101 is exposed, a composite steel pipe 10 in which the termination portion of the power cable 100 is accommodated, and a conductor lead connected to the conductor 101. Rod 20. In this example, it is an air termination connection part. Here, in the terminal connection part 1 and the composite steel pipe 10, the side from which the conductor lead bar 20 is drawn out (upper side in FIG. 1 and FIG. 3) is on the opposite side, in other words, the terminal part of the power cable 100 is inserted. The side to be used is the bottom. Moreover, let the axial direction of the composite soot tube 10 be a longitudinal direction.

  As shown in FIG. 1, the composite soot tube 10 includes an insulating cylinder 11, a jacket portion 12 molded on the outer peripheral surface of the insulating cylinder 11, and a lower metal fitting 13 provided at the lower end of the insulating cylinder 11. The lower metal fitting 13 has a lower electrode 131 disposed at the lower end portion of the insulating cylinder 11 and a flange portion 132 formed at the lower end of the lower electrode 131. One of the characteristics of the composite soot tube 10 is that a gap 15 is formed between the lower end surface of the insulating tube 11 and the flange portion 132 of the lower metal fitting 13 so as to open to the outer peripheral side, as shown in FIG. Another feature of the composite soot tube 10 is that the jacket portion 12 is formed so as to cover at least a part of the outer peripheral surface of the flange portion 132, and the polymer material constituting the jacket portion 12 enters the gap 15. It is in. Hereinafter, the structure of the termination | terminus connection part 1 and the composite soot pipe 10 is demonstrated in detail.

<Power cable>
As shown in FIG. 3, the power cable 100 includes a conductor 101, an insulating layer 102 formed on the outer periphery of the conductor 101, and a shielding layer 103 formed on the outer periphery of the insulating layer 102, and is covered with a sheath 104. ing. Examples of the power cable 100 include a CV cable (crosslinked polyethylene insulating sheath cable). The terminal portion of the power cable 100 is subjected to terminal processing, and is inserted from the lower end side of the composite soot tube 10 and accommodated in the composite soot tube 10.

  As shown in FIG. 3, the terminal portion of the power cable 100 is stripped by terminal processing, and the conductor 101 and the insulating layer 102 are exposed in order from the tip side. In this example, the connection terminal 25 is connected to the tip of the exposed conductor 101 by compression connection. In addition, a pre-mold insulator 40 is attached to the outer periphery of the exposed insulating layer 102 at the end portion of the power cable 100. The pre-mold insulator 40 is a member that alleviates electrical stress from the insulating layer 102 to the insulating cylinder 11 at the cable terminal end, and is formed of, for example, insulating rubber such as ethylene propylene rubber or silicone rubber. The shape of the pre-mold insulator 40 is formed in a cylindrical shape having a large diameter in the middle in the longitudinal direction and tapered at both ends, and a circular hole into which the cable terminal portion is inserted is formed at the center. ing.

<Conductor lead bar>
The conductor lead bar 20 is a round bar member made of a conductive material typified by copper, aluminum, or an alloy thereof, and is electrically connected to the conductor 101 of the power cable 100. As shown in FIGS. 1 and 3, the conductor lead bar 20 is provided at the center of the composite soot tube 10 and is drawn from the upper end side of the composite soot tube 10. The connection part 21 of the conductor lead-out rod 20 which is a connection part with the conductor 101 is arranged in the composite rod tube 10, and in this example, a ring-shaped contact 22 (eg, tulip contact) is attached to the connection part 21. It has been. As shown in FIG. 3, the connection terminal 25 connected to the conductor 101 is inserted into the contact 22 so that the conductor 101 and the conductor lead bar 20 are electrically connected.

<Composite pipe>
(Insulated tube)
The insulating cylinder 11 is a cylindrical member made of an insulating material having excellent mechanical strength, for example, an insulating resin such as epoxy resin or fiber reinforced plastic (FRP). In this example, the insulating cylinder 11 is made of an epoxy resin and is molded on the outer peripheral surface of the conductor lead bar 20. As shown in FIG. 3, the insulating cylinder 11 of this example has a hollow space in which the terminal portion of the power cable 100 is accommodated. The insulating cylinder 11 has a large-diameter portion with a large inner diameter on the lower side where the terminal portion of the power cable 100 is accommodated, and a small-diameter portion with an inner diameter smaller than the large-diameter portion on the upper side where the conductor lead bar 20 is disposed. It has become. A lower fitting 13 having a lower electrode 131 and a flange portion 132 is integrally provided at the lower end of the insulating cylinder 11.

(Coat)
The outer cover 12 is made of a polymer material having excellent weather resistance and electrical insulation performance, for example, insulating rubber such as silicone rubber or ethylene propylene rubber. In this example, the jacket portion 12 is made of silicone rubber and is molded on the outer peripheral surface of the insulating cylinder 11. As shown in FIG. 1, a plurality of umbrella-shaped ridges 121 are formed on the outer peripheral surface of the jacket portion 12 of this example so as to be spaced apart in the longitudinal direction. By forming the plurality of eaves 121 on the outer peripheral surface of the outer jacket portion 12, the creepage distance of the outer envelope portion 12 is increased, and the insulating performance of the composite rod tube 10 can be enhanced.

  The jacket portion 12 is formed so as to straddle the insulating cylinder 11 and the lower metal fitting 13 (flange portion 132). Specifically, as shown in FIG. 2, the lower end side of the jacket portion 12 extends from the insulating cylinder 11 to the flange portion 132, and at least a part of the outer peripheral surface of the flange portion 132 is formed on the jacket portion 12. It has an extension 122 that covers it. Since the extended portion 122 is formed by extending the lower end side of the jacket portion 12, it is possible to prevent foreign substances such as water from entering the insulating tube 11 from between the insulating tube 11 and the flange portion 132. Moreover, by having the extension part 122, the creeping distance of the jacket part 12 becomes longer, and the insulation performance of the composite steel pipe 10 can be improved. The length of the extension 122 (a in FIG. 2) is, for example, from 10 mm to 50 mm, and further from 20 mm to 40 mm, and is about 30 mm in this example. The length of the extension part 122 here refers to the distance from the position of the upper end face of the flange part 132 to the lower end face of the extension part 122. The thickness of the extension 122 (t2 in FIG. 2) is, for example, 3 mm or more and 6 mm or less, and is about 4 mm in this example.

(Bottom bracket)
The lower metal fitting 13 is a ring-shaped member made of a conductive material typified by copper, aluminum, or an alloy thereof, and is provided at the lower end of the insulating cylinder 11 as shown in FIG. The lower metal fitting 13 includes a cylindrical lower electrode 131 provided at the lower end portion of the insulating cylinder 11 and a flange portion 132 formed to protrude radially outward from the lower end of the lower electrode 131.

  The lower electrode 131 has a function of relaxing the electric field, and controls the electric field in the lower part of the composite steel tube 10 where the electric field tends to concentrate, thereby improving the insulation performance of the composite steel tube 10. The flange portion 132 is exposed from the insulating cylinder 11 and faces the lower end surface of the insulating cylinder 11. In this example, as shown in FIG. 2, the outer peripheral surface of the lower end portion of the insulating cylinder 11 and the outer peripheral surface of the flange portion 132 are flush or substantially flush.

(Gap)
As shown in FIG. 2, a gap 15 that opens to the outer peripheral side is formed between the insulating cylinder 11 and the flange portion 132. And the polymer material of the jacket part 12 has penetrated into the gap 15, and the jacket part 12 has a penetration part 123 that penetrates into the gap 15. The width of the gap 15 (the distance between the lower end surface of the insulating cylinder 11 and the upper end surface of the flange portion 132) is set to a width that allows the polymer material to enter when the outer cover portion 12 is molded. Since the polymer material of the jacket portion 12 penetrates into the gap 15, air in the gap 15 is removed when the jacket portion 12 is molded. Therefore, bubble marks generated on the surface of the jacket portion 12 during molding. Can be reduced.

  The opening width of the gap 15 (w in FIG. 2) is, for example, 1 mm or more. As a result, the polymer material easily enters the gap 15 when the jacket portion 12 is molded, and the air in the gap 15 is easily removed. Therefore, generation | occurrence | production of a bubble trace can be reduced effectively. Although the upper limit of the opening width of the clearance gap 15 is not specifically limited, For example, it is mentioned that it is 10 mm or less. When the opening width of the gap 15 is 10 mm or less, the width of the intrusion portion 123 of the jacket portion 12 is 10 mm or less, and the intrusion portion 123 is not easily damaged by bending strain when the composite rod 10 is subjected to a bending test. 12 mechanical strength is easy to ensure. In this example, the opening width of the gap 15 is about 6 mm. The opening width of the gap 15 here refers to the outer peripheral side of the interval between the lower end surface of the insulating cylinder 11 and the upper end surface of the flange portion 132.

  The depth of the gap 15 (d in FIG. 2) is, for example, 10 mm or more and 50 mm or less. The bottom of the inner periphery side of the gap 15 reaches the lower electrode 131, and the depth of the gap 15 is determined by the distance between the outer peripheral surface of the lower end portion of the insulating cylinder 11 and the outer peripheral surface of the lower electrode 131. That is, the depth of the gap 15 is the same as the thickness (t1 in FIG. 2) outside the insulating cylinder 11 that covers the outer peripheral surface of the lower electrode 131. When the depth of the gap 15 is 10 mm or more, it is possible to secure the thickness in the radial direction of the insulating cylinder 11 and suppress a decrease in the dielectric strength and mechanical strength of the lower end portion of the insulating cylinder 11. When the depth of the gap 15 is 50 mm or less, an increase in diameter of the lower end portion of the insulating cylinder 11 can be suppressed. In this example, the depth of the gap 15 (the thickness on the outside of the insulating cylinder 11) is about 30 mm. Here, the depth of the gap 15 refers to the distance from the opening to the bottom of the gap 15 (synonymous with the interval between the outer peripheral surface of the lower end portion of the insulating cylinder 11 and the outer peripheral surface of the lower electrode 131).

  On the other hand, the distance between the inner peripheral surface of the lower end portion of the insulating tube 11 and the inner peripheral surface of the lower electrode 131, in other words, the inner thickness of the insulating tube 11 covering the inner peripheral surface of the lower electrode 131 (t3 in FIG. 2). ) Is set to a thickness necessary for molding the lower metal fitting 13 (lower electrode 131) in the insulating cylinder 11. The inner thickness of the insulating cylinder 11 is about 8 mm in this example. In this example, the structure in which the lower electrode 131 is embedded in the lower end portion of the insulating cylinder 11 is illustrated, but the inner peripheral surface of the insulating cylinder 11 and the inner peripheral surface of the lower electrode 131 are flush with each other. The inner peripheral surface of the electrode 131 may be exposed from the insulating cylinder 11 (in this case, t3 = 0).

  In this example, as shown in FIG. 2, the entire gap 15 is filled with the polymer material of the jacket portion 12, but it is also acceptable if the polymer material penetrates from the opening of the gap 15 to the middle of the depth. To do. In this case, it is mentioned that the penetration | invasion amount of a polymer material is 50% or more of the depth of the clearance gap 15 and also 60% or more and 80% or more. If the polymer material penetrates more than half of the gap 15, air is removed to some extent from the gap 15 when the jacket 12 is molded, so that the effect of reducing the occurrence of bubble marks can be obtained. When the entire gap 15 is filled with the polymer material of the outer cover portion 12 as in this example, the polymer material spreads in the gap 15 and the air in the gap 15 is largely removed. Therefore, generation | occurrence | production of a bubble trace can be reduced significantly and the bubble trace which generate | occur | produces on the surface of the jacket part 12 can be eliminated.

  Further, as shown in FIG. 2, the gap 15 in this example is formed so as to increase in width toward the outer peripheral side. That is, the opening width of the gap 15 is wider than the width on the bottom side. In this case, since the opening on the outer peripheral side of the gap 15 is wide, the polymer material is likely to enter the gap 15 when the jacket portion 12 is molded, and the air in the gap 15 is easily removed. Therefore, generation | occurrence | production of a bubble trace can be reduced effectively. In this example, the lower end surface of the insulating cylinder 11 facing the flange portion 132 is inclined with respect to the direction orthogonal to the axial direction of the insulating cylinder 11. Specifically, the lower end surface of the insulating cylinder 11 is an inclined surface that inclines in a direction away from the upper end surface of the flange portion 132 toward the outer peripheral side. Thereby, the width of the gap 15 is formed so as to become narrower from the opening toward the bottom side. Unlike this example, for example, the lower end surface of the insulating cylinder 11 may be substantially parallel to the upper end surface of the flange portion 132, and the width of the gap 15 may be substantially the same from the opening toward the bottom side. .

<Production method of composite steel pipe>
1 and 2 can be manufactured, for example, by a manufacturing method including the following steps.
The process of molding the insulating cylinder 11 integrally with the lower metal fitting 13 The process of molding the jacket portion 12 on the insulating cylinder 11 integrated with the lower metal fitting 13

(1. Molding process of insulating cylinder)
The insulating cylinder 11 is formed by molding integrally with the lower metal fitting 13. In the case of this example, an insulating resin is injected in a state where the conductor lead bar 20 and the lower metal fitting 13 are arranged in the mold, and the insulating cylinder 11 is directly molded on the outer peripheral surface of the conductor lead bar 20. The lower metal fitting 13 is molded integrally with the lower end of the. Thereby, the lower metal fitting 13 is integrally provided at the lower end of the insulating cylinder 11, and the lower electrode 131 is disposed at the lower end portion of the insulating cylinder 11. A contact 22 may be attached to the connection portion 21 of the conductor lead bar 20 in advance.

  In this process, when the insulating cylinder 11 is molded, the gap 15 described above is formed between the lower end surface of the insulating cylinder 11 and the flange portion 132 of the lower metal fitting 13. Spacers are arranged on the end faces. This spacer forms a gap 15 that opens to the outer peripheral side between the lower end surface of the molded insulating cylinder 11 and the flange portion 132. The shape of the spacer is a shape corresponding to the gap 15 to be formed. Thus, a gap 15 is formed between the insulating tube 11 and the flange portion 132 in the insulating tube 11 in which the lower metal fitting 13 is molded integrally.

  In this example, since the lower end surface of the insulating cylinder 11 is the above-described inclined surface, the upper surface of the spacer is inclined according to the inclined surface. If a release agent is applied to the surface (upper surface) of the insulating cylinder 11 where the insulating resin contacts, the spacer can be easily removed after the insulating cylinder 11 is molded. Further, fine irregularities may be formed by performing a surface treatment such as sandblasting on the upper surface of the spacer with which the insulating resin of the insulating cylinder 11 contacts. Thereby, fine irregularities can be formed on the lower end surface of the insulating cylinder 11. The lower end surface of the insulating cylinder 11 formed by the spacer is one of the inner surfaces of the gap 15, and fine irregularities are formed, so that the polymer material (the intrusion portion 123) of the outer cover portion 12 molded in a subsequent process is formed. ) And the gap 15 are increased, and the adhesion of the jacket portion 12 to the insulating cylinder 11 is improved.

  In this example, a release agent is also applied to the surface of the lower metal fitting 13 (lower electrode 131 etc.) with which the insulating resin of the insulating cylinder 11 comes into contact, and the insulating cylinder 11 and the lower metal fitting 13 are bonded by the insulating resin. I'm trying not to be.

(2. Molding process of the jacket part)
The outer cover 12 is molded and formed on the outer peripheral surface of the insulating cylinder 11 with the lower metal fitting 13 integrated. Specifically, the above-described insulating cylinder 11 integrally provided with the lower metal fitting 13 is placed in a mold, a polymer material is injected, and the outer cover portion 12 is directly molded on the outer peripheral surface of the insulating cylinder 11. An outer cover 12 with 121 is formed.

  In this step, the outer cover 12 is molded so as to cover at least a part of the outer peripheral surface of the flange 132 of the lower metal member 13, so that the outer cover 12 is connected to the insulating cylinder 11 and the lower metal 13 (flange 132). To straddle. Thereby, the extension part 122 is formed in the jacket part 12. At this time, the intrusion portion 123 is formed by the polymer material of the outer jacket portion 12 entering the gap 15 formed between the insulating cylinder 11 and the flange portion 132.

  When the jacket portion 12 is molded, the polymer material enters the inside through the opening on the outer peripheral side of the gap 15, so that the air in the gap 15 is expelled and the air in the gap 15 is removed. Therefore, since it is difficult for air to remain in the gap 15, bubble traces caused by the air in the gap 15 are generated on the surface of the outer cover portion 12 located on the gap 15 (a portion straddling the insulating cylinder 11 and the flange portion 132). It becomes difficult to do. Therefore, the bubble trace which generate | occur | produces on the surface of the jacket part 12 at the time of a molding is reduced.

  In this example, as described above, since the opening width of the gap 15 is set to 1 mm or more, it is easy to allow the polymer material to enter the gap 15 when the outer cover 12 is molded, and the air in the gap 15 is removed. easy. In addition, since the gap 15 of this example is formed so as to increase in width toward the outer peripheral side, the polymer material easily enters the gap 15 and the air in the gap 15 is easily removed. Therefore, generation | occurrence | production of a bubble trace can be reduced effectively.

  Furthermore, if the entire gap 15 is filled with the polymer material of the jacket portion 12 as in this example, the polymer material spreads in the gap 15 and the air in the gap 15 is significantly removed. Therefore, generation | occurrence | production of a bubble trace can be reduced significantly and the bubble trace which generate | occur | produces on the surface of the jacket part 12 can be eliminated.

  Further, in this example, a release agent is applied to the surface of the flange portion where the polymer material of the jacket portion 12 contacts, so that the jacket portion 12 and the lower metal fitting 13 are not bonded by the polymer material. Therefore, the insulating cylinder 11 and the jacket portion 12 are prevented from being bonded to the lower metal fitting 13, and as a result, the insulating cylinder 11 and the outer jacket portion 12 are damaged by the stress caused by the difference in thermal expansion with the lower metal fitting 13. Can be suppressed.

  In addition, when molding the jacket portion 12, it is easy to fill the gap 15 with a polymer material if the mold is evacuated in advance.

<Terminal connection>
3 can be constructed by, for example, a manufacturing method including the following steps.
The step of preparing the composite rod 10 The step of terminating the terminal portion of the power cable 100 The step of assembling the terminal connection portion 1 by inserting the terminal portion of the power cable 100 into the composite rod 10

(1. Preparation process for composite pipes)
The composite soot tube 10 of the embodiment described above is prepared. The composite soot tube 10 may be prepared in advance at a factory or the like.

(2. Terminal process of power cable terminal)
Terminal processing is applied to the terminal portion of the installed power cable 100. Specifically, after removing the sheath 104 at the end portion of the power cable 100, the cable end portion is stripped to expose the conductor 101, the insulating layer 102, and the like in order. In this example, the connection terminal 25 is compression-connected to the exposed tip of the conductor 101. Further, the premold insulator 40 is attached to the outer periphery of the exposed insulating layer 102.

  The terminal portion of the power cable 100 that has undergone terminal processing is inserted from the lower end side of the composite rod tube 10, and the cable terminal portion is accommodated in the composite rod tube 10 (the hollow space of the insulating cylinder 11). Then, the connection terminal 25 connected to the conductor 101 is inserted into the contact 22 attached to the connection portion 21 of the conductor lead bar 20 to electrically connect the conductor 101 and the conductor lead bar 20. Thereby, the termination | terminus connection part 1 is assembled.

  In the case of the termination connection portion 1 shown in FIG. 3, the termination connection portion 1 is constructed by attaching the mounting bracket 30 to the lower end surface of the lower bracket 13 with a bolt or the like and installing the mounting bracket 30 via the support insulator 31. Yes. The lower metal fitting 13 is grounded.

"effect"
In the composite soot tube 10 according to the embodiment, the polymer material of the jacket portion 12 penetrates into the gap 15 formed between the insulating cylinder 11 and the flange portion 132 of the lower metal fitting 13, so that the jacket portion is molded. Bubble marks generated on the surface of 12 can be reduced. Therefore, the composite soot tube 10 is excellent in appearance because it is difficult for noticeable bubble marks to be generated on the surface of the jacket portion 12.

  The terminal connection portion 1 according to the embodiment includes the composite soot tube 10 described above, so that no noticeable bubble marks are generated on the surface of the jacket portion 12 in the composite soot tube 10 and the composite soot tube 10 is excellent in appearance. .

<Application>
The composite soot tube 10 according to the embodiment can be suitably used for the terminal connection portion 1. The termination connection unit 1 according to the embodiment can be suitably used for connection to an overhead line or the like at the termination of the power cable 100.

DESCRIPTION OF SYMBOLS 1 Termination connection part 10 Composite soot pipe 11 Insulation cylinder 12 Outer part 121 襞 122 Extension part 123 Intrusion part 13 Lower metal fitting 131 Lower electrode 132 Flange part 15 Crevice 20 Conductor extraction rod 21 Connection part 22 Contact 25 Connection terminal 30 Mounting metal fitting 31 Support insulator 40 Premolded insulator 100 Power cable 101 Conductor 102 Insulating layer 103 Shielding layer 104 Sheath

Claims (5)

An insulating cylinder having a hollow space in which the terminal portion of the power cable is accommodated;
A jacket portion molded from a polymer material on the outer peripheral surface of the insulating cylinder;
A lower electrode provided at a lower end portion of the insulating cylinder, and a lower metal fitting having a flange portion formed at the lower end of the lower electrode and facing the lower end surface of the insulating cylinder,
Between the insulating cylinder and the flange portion, there is a gap opening on the outer peripheral side,
The outer cover part is formed so as to straddle the insulating cylinder and the lower metal fitting so as to cover at least a part of the outer peripheral surface of the flange part, and the polymer material of the outer cover part enters the gap.碍 管.   The composite soot tube according to claim 1, wherein an opening width of the gap is 1 mm or more.   The composite soot tube according to claim 1 or 2, wherein the gap is formed so as to increase in width toward an outer peripheral side.   The composite soot tube according to any one of claims 1 to 3, wherein the entire gap is filled with a polymer material of the jacket portion.   The termination | terminus connection part provided with the composite soot pipe of any one of Claims 1-4.

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