Combined prefabricated intermediate joint for power cables

Abstract

The utility model discloses a kind of combined prefabricated intermediate joints for power cable, it is related to cable accessory technical field, including connecting assembly, insulating cylinder, two stress cone assemblies, connecting ring and two shell assemblies, connecting assembly is used to electrically connect two cable;Insulating cylinder is sleeved on the outside of connecting assembly;Two ends of insulating cylinder are equipped with stress cone assembly, connecting assembly is located between two stress cone assemblies;Connecting ring is set to one end of insulating cylinder, and connecting ring is fixedly connected with insulating cylinder;Two ends of insulating cylinder are equipped with shell assembly, and shell assembly is sleeved on the outside of insulating cylinder, and two shell assemblies are fixedly connected by connecting ring, to wrap insulating cylinder in the inside of shell assembly.The utility model discloses a kind of combined prefabricated intermediate joints for power cable, can select the material of connecting ring according to actual application scene, realize the metal shielding layer of intermediate joint as needed connection or interruption.

Description

Technical Field

[0001] This utility model relates to the field of cable accessories technology, and in particular to a combined prefabricated intermediate joint for AC ultra-high voltage, AC extra-high voltage, DC high voltage, and DC extra-high voltage power cables. Background Technology

[0002] With the development of new energy construction, ultra-high voltage power transmission technology has the advantages of low loss and long-distance transmission. However, high voltage power transmission has extremely stringent requirements for system reliability. During the laying of transmission lines, intermediate joints are used as components to connect two sections of cable and rebuild the cable body structure.

[0003] Cables include a metallic shielding layer. After fabricating a cable joint, in some cases, it's necessary to connect the metallic shielding layers of the two cable segments and then centrally ground the shielding. In other cases, due to the high voltage transmitted by the cable, the resulting electric field strength is large, leading to a large current within the metallic shielding layer. This current passing through the metallic shielding layer can easily cause heat generation when it reaches the joint, necessitating interrupting the connection of the metallic shielding layers at the joint and grounding each shielding layer separately. Existing joint structures involve complex structural modifications and time-consuming construction when choosing between connecting or interrupting the metallic shielding layer as needed. Utility Model Content

[0004] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a prefabricated composite intermediate joint for power cables, which allows for the selection of the connecting ring material according to the actual application scenario, enabling the metal shielding layer of the intermediate joint to be connected or interrupted as needed.

[0005] According to an embodiment of the present invention, a prefabricated intermediate joint for power cables includes: a connecting component, the connecting component being used to electrically connect two sections of cable; An insulating cylinder is fitted onto the outside of the connecting assembly; Two stress cone assemblies are provided at both ends of the insulating cylinder, and the connecting assembly is located between the two stress cone assemblies; A connecting ring is disposed at one end of the insulating cylinder and is fixedly connected to the insulating cylinder. Two protective shell assemblies are provided at both ends of the insulating cylinder, and the protective shell assemblies are fitted onto the outside of the insulating cylinder. The two protective shell assemblies are fixedly connected by the connecting ring to wrap the insulating cylinder inside the protective shell assemblies.

[0006] The combined prefabricated intermediate joint for power cables according to the embodiments of this utility model has at least the following beneficial effects: the connecting component is used to electrically connect the conductors of two cable segments; the connecting component, the insulating cylinder, the stress cone component, and the sheath component constitute the intermediate joint of the cable; the two sheath components are connected by a connecting ring, and the connecting ring made of a metal conductive material or a non-metallic insulating material can be selected according to actual needs to meet the requirement that the metal shielding layer of the intermediate joint can be connected or interrupted as needed.

[0007] According to some embodiments of the present invention, a positioning ring is provided on the outer side of the insulating cylinder, the positioning ring is fixedly connected to the insulating cylinder, and a connecting bolt is provided between the connecting ring and the positioning ring.

[0008] According to some embodiments of the present invention, the outer wall of the connecting ring is provided with an annular relief groove, the connecting bolt is disposed in the relief groove, and the screwing direction of the connecting bolt is from the connecting ring toward the positioning ring, so that the nut of the connecting bolt is located in the relief groove.

[0009] According to some embodiments of the present invention, the stress cone assembly includes a cone and a cone support. The cone has a through hole for cable insertion. The outer side wall of the cone has a first conical surface, and the inner side wall of the insulating cylinder has a second conical surface. The cone is inserted into the end of the insulating cylinder, and the cone support is fitted onto the outer side of the cone, with the cone support located on the side away from the insulating cylinder. The cone support is fixedly connected to the insulating cylinder or the connecting ring, such that the first conical surface abuts against the second conical surface.

[0010] According to some embodiments of the present invention, an annular connecting plate is provided on the outer side of the cone support, a first screw is provided between the cone support and the connecting plate, and a second screw is provided between the connecting plate and the connecting ring.

[0011] According to some embodiments of the present invention, the first screw is fitted with a spring, one end of the spring abuts against the cone support, and the other end of the spring abuts against the connecting plate. The spring is configured to push the cone support toward the insulating cylinder.

[0012] According to some embodiments of this utility model, the connecting ring is a metal connecting ring, and a grounding post is provided on the outer side of the protective shell assembly.

[0013] According to some embodiments of the present invention, the connecting assembly includes a connecting tube, two biteers, and two wedge-shaped cylinders. The biteers are used to mount the conductors of the cable. The outer side wall of the biteer is provided with a third conical surface, and the inner side wall of the wedge-shaped cylinder is provided with a fourth conical surface. The wedge-shaped cylinder is mounted on the outer side of the biteer and inserted into the inner side of the connecting tube. The side of the wedge-shaped cylinder with the smaller inner diameter faces the center of the connecting tube, and the third conical surface abuts against the fourth conical surface.

[0014] According to some embodiments of the present invention, the connecting assembly further includes two stop sleeves, which are disposed between the stress cone assembly and the bite device. One end of the stop sleeve abuts against the stress cone assembly, and the other end of the stop sleeve abuts against the bite device to confine the bite device within the connecting tube.

[0015] According to some embodiments of the present invention, the outer side of the protective shell assembly is provided with an insulating protective layer.

[0016] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein: Figure 1 This is a schematic diagram of the structure of the combined prefabricated intermediate joint for power cables according to an embodiment of the present invention; Figure 2 This is a partially enlarged structural diagram of a prefabricated intermediate joint for power cables according to an embodiment of this utility model; Figure 3 This is a partially enlarged structural diagram of the connecting component in an embodiment of this utility model.

[0018] Icon labels: Connecting assembly 100, connecting pipe 110, engagement device 120, wedge cylinder 130, stop sleeve 140, insulating cylinder 200, positioning ring 210, connecting bolt 220, stress cone assembly 300, cone 310, cone support 320, connecting plate 330, first screw 340, second screw 350, spring 360, connecting ring 400, clearance groove 410, protective shell assembly 500, grounding post 510. Detailed Implementation

[0019] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0020] In the description of this utility model, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0021] In the description of this utility model, "multiple" refers to two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features or their sequential relationship.

[0022] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0023] Reference Figure 1 As shown, a combined prefabricated intermediate joint for power cables according to an embodiment of the present invention includes a connecting component 100, an insulating cylinder 200, two stress cone components 300, a connecting ring 400, and two protective shell components 500.

[0024] The connecting assembly 100 is used to electrically connect two cable segments; the insulating cylinder 200 is fitted onto the outside of the connecting assembly 100; stress cone assemblies 300 are provided at both ends of the insulating cylinder 200, and the connecting assembly 100 is located between the two stress cone assemblies 300; a connecting ring 400 is provided at one end of the insulating cylinder 200, and the connecting ring 400 is fixedly connected to the insulating cylinder 200; a protective shell assembly 500 is provided at both ends of the insulating cylinder 200, and the protective shell assembly 500 is fitted onto the outside of the insulating cylinder 200, and the two protective shell assemblies 500 are fixedly connected by the connecting ring 400 to wrap the insulating cylinder 200 inside the protective shell assembly 500.

[0025] The connecting assembly 100 is preferably made of a material with good electrical conductivity and is used to electrically connect the conductor sections of two cable segments. An insulating cylinder 200 is fitted over the connecting assembly 100 to restore the insulation layer of the intermediate joint. Stress cone assemblies 300 are provided at both ends of the insulating cylinder 200. Technicians know that the stress cone assemblies 300 should be located within the cable's insulation shielding layer to improve the electric field distribution of the cable and prevent insulation layer breakdown caused by electrical stress concentration. A protective shell assembly 500 is located outside the insulating cylinder 200 and protects the intermediate joint. Specifically, the protective shell assembly 500 protects the insulating cylinder 200, stress cone assemblies 300, and connecting assembly 100 from external damage. Preferably, the protective shell assembly 500 is made of copper and can be electrically connected to the cable's metal shielding layer.

[0026] In some embodiments, it is necessary to connect the metal shielding layers of the two cable segments and then centrally ground the metal shielding layers. The connecting ring 400 can be made of a conductive metal material, and the two sheath assemblies 500 are connected through the connecting ring 400 to form a conductive connection, thereby connecting the metal shielding layers of the two cable segments.

[0027] In other embodiments, due to the high voltage transmitted by the cable, the resulting electric field strength is large, leading to a large current within the metal shielding layer. This current, passing through the metal shielding layer, easily generates heat when it reaches the intermediate joint. Therefore, it is necessary to interrupt the connection of the metal shielding layers of the two cable sections at the intermediate joint and ground the metal shielding layers separately. In this case, a non-metallic insulating connecting ring 400 can be used to connect the two sheathing assemblies 500. Since the two sheathing assemblies 500 are not conductive, grounding can be provided on each of the two sheathing assemblies 500. That is, it can be understood that the connecting ring 400 is a metal connecting ring, and a grounding post 510 is provided on the outer side of the sheathing assembly 500.

[0028] It is understandable that a positioning ring 210 is provided on the outer side of the insulating cylinder 200, the positioning ring 210 is fixedly connected to the insulating cylinder 200, and a connecting bolt 220 is provided between the connecting ring 400 and the positioning ring 210.

[0029] The positioning ring 210 can be part of the insulating cylinder 200, meaning the positioning ring 210 and the insulating cylinder 200 are an integral structure. Alternatively, the positioning ring 210 can be interference-fitted with the insulating cylinder 200 to fix the positioning ring 210 to the insulating cylinder 200. In this case, the positioning ring 210 provides a mounting base for the connecting ring 400. Preferably, the connecting ring 400 and the positioning ring 210 are detachably connected. Specifically, the connecting ring 400 and the positioning ring 210 are connected by connecting bolts 220, which are detachable and easy to remove.

[0030] It is understood that the outer wall of the connecting ring 400 is provided with an annular relief groove 410, and the connecting bolt 220 is disposed within the relief groove 410. The screwing direction of the connecting bolt 220 is from the connecting ring 400 towards the positioning ring 210, so that the nut of the connecting bolt 220 is located within the relief groove 410. In this structure, the nut of the connecting bolt 220 can be prevented from contacting structures in the environment, thus avoiding wear. Furthermore, it allows the outer surfaces of the connecting ring 400 and the positioning ring 210 to remain flat and without protrusions, facilitating the wrapping of insulating material. It should be understood that the connecting bolt 220 screws into the positioning ring 210 but does not penetrate it; that is, the screw hole on the positioning ring 210 is preferably a blind hole.

[0031] It is understood that the stress cone assembly 300 includes a cone 310 and a cone support 320. The cone 310 is provided with a through hole for cable insertion. The outer side wall of the cone 310 is provided with a first cone surface, and the inner side wall of the insulating cylinder 200 is provided with a second cone surface. The cone 310 is inserted into the end of the insulating cylinder 200, and the cone support 320 is fitted onto the outer side of the cone 310. The cone support 320 is located on the side away from the insulating cylinder 200. The cone support 320 is fixedly connected to the insulating cylinder 200 or the connecting ring 400, so that the first cone surface abuts against the second cone surface.

[0032] It is important to understand that since a connecting ring 400 is required at one end of the insulating cylinder 200, the cone support 230 is connected to the insulating cylinder 200 or to the connecting ring 400. Specifically, at the end of the insulating cylinder 200 without the connecting ring 400, the cone support 230 is directly connected to the insulating cylinder 200; at the end of the insulating cylinder 200 with the connecting ring 400, the cone support 230 is connected to the connecting ring 400. Both structures can fix the cone support 230. The fixed cone support 230 serves to limit and support the cone 310. Simultaneously, the cone 310 and the insulating cylinder 200 each have a first conical surface and a second conical surface, which abut against each other to confine the cone 310 to a preset position.

[0033] Furthermore, a fixed connection structure between the cone support 320 and the connecting ring 400 is provided. The outer side of the cone support 320 is provided with an annular connecting plate 330, a first screw 340 is provided between the cone support 320 and the connecting plate 330, and a second screw 350 is provided between the connecting plate 330 and the connecting ring 400.

[0034] Understandably, the first screw 340 is fitted with a spring 360, one end of which abuts against the cone support 320 and the other end of which abuts against the connecting plate 330. The spring 360 is configured to push the cone support 320 toward the insulating cylinder 200.

[0035] exist Figure 2In the structure shown, the spring 360 is configured in a compressed state. The compressed spring 360 has a tendency to return to its original position, pushing the cone support 320 away from the connecting plate 330. The cone support 320 is positioned between the connecting plate 330 and the insulating cylinder 200, and the connecting plate 330 and the insulating cylinder 200 are in a fixed state; that is, the cone support 320 will move towards the direction of the insulating cylinder 200. In this structure, the cone support 320 will push the cone 310, causing the first cone surface to abut against the second cone surface, making the fixation of the cone 310 more reliable.

[0036] Reference Figure 3 As shown, it can be understood that the connecting assembly 100 includes a connecting tube 110, two bites 120 and two wedges 130. The bites 120 are used to hold the conductors of the cable. The outer side wall of the bites 120 is provided with a third conical surface. The inner side wall of the wedges 130 is provided with a fourth conical surface. The wedges 130 are fitted on the outer side of the bites 120 and inserted into the inner side of the connecting tube 110. The side of the wedges 130 with the smaller inner diameter faces the center of the connecting tube 110. The third conical surface abuts against the fourth conical surface.

[0037] After the clamp 120 is fitted onto the cable conductor, the wedge cylinder 130 is fitted on top, and finally inserted into the connecting tube 110. Since the smaller inner diameter side of the wedge cylinder 130 faces the center of the connecting tube 110, when the wedge cylinder 130 moves toward the port of the connecting tube 110, the smaller inner diameter part of the wedge cylinder 130 will squeeze the clamp 120 and the connecting tube 110. Because the inner diameter of the connecting tube 110 remains unchanged and the outer diameter of the cable conductor remains unchanged, the pressure between the cable conductor, the clamp 120, the wedge cylinder 130, and the connecting tube 110 increases, thus preventing the wedge cylinder 130 from continuing to move toward the port of the connecting tube 110, effectively preventing the wedge cylinder 130 from coming off, and ensuring a reliable connection of the cable conductor.

[0038] Understandably, the connecting assembly 100 also includes two stop sleeves 140, which are disposed between the stress cone assembly 300 and the bite 120. One end of the stop sleeve 140 abuts against the stress cone assembly 300, and the other end of the stop sleeve 140 abuts against the bite 120 to confine the bite 120 within the connecting tube 110.

[0039] Understandably, the outer side of the housing assembly 500 is provided with an insulating sheath, which serves a protective function.

[0040] In some embodiments, the two cable segments to be spliced ​​are placed at the splicing position, the joint point is determined, and the cable segments are marked. A certain length is left from the marked point towards the end of the cable, and the excess cable is cut off.

[0041] Determine the end positions of the cable's outer sheath and metal sheath, strip the corresponding length of the outer and metal sheaths, and then straighten the cable by heating. Measure a certain length from the cable end, strip the cable insulation layer and insulation shielding layer, exposing a certain length of conductor, and then perform surface treatment on the conductor.

[0042] The two cable sections are divided into cable A and cable B. Sheath assemblies 500 and cone supports 320 are installed on both cable A and cable B respectively. The installation position of the cone 310 is then determined. The surface of the cable insulation layer and the inner and outer surfaces of the cone 310 are cleaned, and silicone oil is applied. The cones 310 are then installed at the corresponding positions on cable A and cable B respectively. Next, the stop sleeve 140 and the clamping device 120 are installed sequentially on the conductor of cable A, and then the wedge cylinder 130 is pressed tightly onto the clamping device 120. The same operation is performed on cable B. After the installation of cable B is completed, cable A and cable B, with the cone 310, stop sleeve 140, clamping device 120, and wedge cylinder 130 installed, are pushed into the insulating cylinder 200 until they are inserted into the connecting tube 110 inside the insulating cylinder 200. Before inserting into the insulating cylinder 200, the end of cable B is threaded through the connecting ring 400.

[0043] Finally, connect the housing assembly 500.

[0044] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A prefabricated intermediate joint for power cables, characterized in that, include: A connecting assembly for electrically connecting two cable segments; An insulating cylinder is fitted onto the outside of the connecting assembly; Two stress cone assemblies are provided at both ends of the insulating cylinder, and the connecting assembly is located between the two stress cone assemblies; A connecting ring is disposed at one end of the insulating cylinder and is fixedly connected to the insulating cylinder. Two protective shell assemblies are provided at both ends of the insulating cylinder, and the protective shell assemblies are fitted onto the outside of the insulating cylinder. The two protective shell assemblies are fixedly connected by the connecting ring to wrap the insulating cylinder inside the protective shell assemblies.

2. The prefabricated intermediate joint for power cables according to claim 1, characterized in that, A positioning ring is provided on the outer side of the insulating cylinder, and the positioning ring is fixedly connected to the insulating cylinder. A connecting bolt is provided between the connecting ring and the positioning ring.

3. The prefabricated intermediate joint for power cables according to claim 2, characterized in that, The outer wall of the connecting ring is provided with an annular relief groove, the connecting bolt is disposed in the relief groove, and the screwing direction of the connecting bolt is from the connecting ring toward the positioning ring, so that the nut of the connecting bolt is located in the relief groove.

4. The prefabricated intermediate joint for power cables according to claim 1, characterized in that, The stress cone assembly includes a cone and a cone support. The cone has a through hole for cable insertion. The outer side wall of the cone has a first conical surface, and the inner side wall of the insulating cylinder has a second conical surface. The cone is inserted into the end of the insulating cylinder, and the cone support is fitted onto the outer side of the cone, with the cone support located away from the insulating cylinder. The cone support is fixedly connected to the insulating cylinder or the connecting ring, such that the first conical surface abuts against the second conical surface.

5. The prefabricated intermediate joint for power cables according to claim 4, characterized in that, The outer side of the cone support is provided with an annular connecting plate, a first screw is provided between the cone support and the connecting plate, and a second screw is provided between the connecting plate and the connecting ring.

6. The prefabricated intermediate joint for power cables according to claim 5, characterized in that, The first screw is fitted with a spring, one end of which abuts against the cone support and the other end of which abuts against the connecting plate. The spring is configured to push the cone support toward the insulating cylinder.

7. The prefabricated intermediate joint for power cables according to claim 1, characterized in that, The connecting ring is a metal connecting ring, and a grounding post is provided on the outside of the protective shell assembly.

8. The prefabricated intermediate joint for power cables according to claim 1, characterized in that, The connecting assembly includes a connecting tube, two biteers, and two wedge-shaped cylinders. The biteers are used to mount the conductors of the cable. The outer side wall of the biteer has a third conical surface, and the inner side wall of the wedge-shaped cylinder has a fourth conical surface. The wedge-shaped cylinder is fitted onto the outer side of the biteer and inserted into the inner side of the connecting tube. The side of the wedge-shaped cylinder with the smaller inner diameter faces the center of the connecting tube, and the third conical surface abuts against the fourth conical surface.

9. The prefabricated intermediate joint for power cables according to claim 8, characterized in that, The connecting assembly further includes two stop sleeves, which are disposed between the stress cone assembly and the bite device. One end of the stop sleeve abuts against the stress cone assembly, and the other end of the stop sleeve abuts against the bite device to confine the bite device within the connecting tube.

10. The prefabricated intermediate joint for power cables according to claim 1, characterized in that, The outer side of the protective housing assembly is provided with an insulating protective layer.

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