Cable centering device and high-voltage cable oil charging terminal
By designing the central device of the cable, the problem of the internal stress cone position of the internal stress cone in the high -pressure cable fuel supply terminal is solved, and the uniformity of the field strength and the stability of the product are achieved, and faults and losses are avoided.
Patent Information
- Application Number
- CN202323651875.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-30
- Publication Date
- 2025-01-24
- Estimated Expiration
- 2033-12-30
AI Technical Summary
The internal stress cone position of the high-voltage cable oil-filled terminal cannot be completely centered, resulting in field strength distortion, severe temperature rise, accelerate product aging, and ultimately leading to failure.
A cable centering device is designed, including a centering inner sleeve, a centering block, and a centering outer jacket. Through the interference fit of these components and the design of the buffer layer, the centering of the cable within the stress cone is ensured.
Effectively avoid the strength of the stress cone position, improve the stability of the product, extend the service life of the product, and avoid losses caused by faults.
Smart Images
Figure CN222395437U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of power cables, in particular to a cable centering device and a high-voltage cable oil-filled terminal. Background Art
[0002] With the continuous development of society and urbanization, my country's electricity consumption continues to increase. Long-distance power transmission adopts overhead lines. After entering the city, large-capacity electricity is input into the city center through high-voltage AC land cables. Power cable lines include cables and cable accessories. Cable accessories are the weak link of cable lines, so the installation reliability of cable accessories is particularly important. Oil-filled terminals are cable accessories. They are installed at the end of the cable to ensure the electrical connection between the cable and the power grid or other electrical equipment, and maintain insulation until the connection point. High-voltage oil-filled power cable terminal products are currently the main product form of high-voltage power cable terminals. In particular, in the ultra-high voltage cable terminal product system, almost all outdoor cable terminals are oil-filled cable terminal products. At present, the oil-filled terminal is filled with insulating medium to form a high-voltage cable oil-filled terminal.
[0003] A stress cone is usually installed in the oil-filled terminal of the high-voltage cable. At present, the position with the highest field strength inside the oil-filled terminal of the high-voltage cable is the stress cone position. Due to the creep of the cable during operation and the high height of the high-voltage insulating sleeve, the cable at the stress cone position inside the insulating sleeve cannot be completely guaranteed to be centered, which may cause distortion of the internal field strength. Under long-term operation of high cables and high loads, this position is prone to severe temperature rise, which accelerates product aging and ultimately causes product failure and causes losses. Utility Model Content
[0004] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide a cable centering device and a high-voltage cable oil-filled terminal, which mainly solve the problem of centering the cable at the stress cone position inside the high-voltage cable oil-filled terminal, ensure the centering degree of the cable at the stress cone position, effectively improve the product stability and avoid strong distortion in the field, which may lead to product failure.
[0005] On the one hand, the utility model provides a cable centering device, which is installed between a cable and a stress cone and is used to keep the cable centered in the stress cone. The cable centering device includes a centering inner sleeve; a centering block, which is sleeved on the centering inner sleeve, and the centering block and the centering inner sleeve form an interference fit;
[0006] A centering outer sleeve is sleeved on the centering block, and the centering outer sleeve and the centering block form an interference fit.
[0007] It can be seen from the above scheme that the centering device is sequentially sleeved on the cable in the stress cone of the oil-filled terminal, and includes a centering outer sleeve, a centering block and a centering inner sleeve from the outside to the inside, and the centering outer sleeve is transitionally matched with the stress cone.
[0008] A buffer layer is arranged between the cable and the central inner sleeve, and the buffer layer is a buffer sleeve formed by wrapping and winding a tape. It can be seen that the buffer layer is used to prevent the inner wall of the central inner sleeve from scratching the outer shielding layer of the cable.
[0009] The center inner sleeve includes two symmetrically arranged semi-cylinders, and the inner diameter of the center inner sleeve is larger than the outer diameter of the cable. It can be seen that the center inner sleeve is used to be sleeved on the outer wall of the buffer layer. Since the outer diameter of the buffer layer cannot be guaranteed to be completely consistent, the center inner sleeve is arranged in two semi-cylinders to reduce installation errors.
[0010] The centering sleeve includes an annular flange and a cylinder coaxially arranged on the annular flange. The diameter of the annular flange is larger than the diameter of the cylinder. The inner diameter of the cylinder forms an interference fit with the outer diameter of the centering block. The annular flange is provided with a sealing ring groove and a mounting hole. It can be seen that the cylinder of the centering sleeve is sleeved on the centering block, the annular flange is used to realize the installation and fixation of the centering sleeve, the sealing ring groove is used to install the sealing ring, and the mounting hole is used to insert the connector to fix the centering sleeve.
[0011] The outer wall of the centering block is provided with a plurality of exhaust grooves, which are arranged in a circumferential array on the outer wall of the centering block along the axial direction of the centering block. The centering block is formed as a whole by stacking a plurality of circular ring blocks. The outer wall of the circular ring block is arranged in an arc surface, and the edge of the centering block along the axial section is wavy. It can be seen that the vertical groove is used to achieve exhaust, which is convenient for subsequent disassembly. The wavy edge of the centering block is used to reduce the contact area between the outer wall of the centering block and the inner wall of the centering jacket, and prevent the outer wall of the centering block from rubbing too much with the inner wall of the cylinder of the centering jacket, thereby reducing the difficulty of installation.
[0012] The centering block is made of silicone rubber, and its Shore hardness is between Shore A50 and 55, and the centering inner sleeve is made of nylon plastic. It can be seen that the centering block is arranged between the centering outer sleeve and the centering inner sleeve, and the centering block is too deformed to affect the installation effect, and the inner wall of the centering inner sleeve is arranged to be smooth.
[0013] On the other hand, the utility model also provides a high-voltage cable oil-filled terminal, which also includes the coaxially arranged stress cone, insulating sleeve, upper seal, lower seal and grounding sleeve, the cable includes a cable core and a cable outer shielding layer covered on the cable core, the cable core is provided with a corrugated tube at the bottom of the cable outer shielding layer, the cable centering device is arranged between the stress cone and the cable outer shielding layer, the insulating sleeve is sleeved on the stress cone, and there is a set gap between the outer wall of the stress cone and the inner wall of the insulating sleeve, the upper seal is arranged at the top of the insulating sleeve, the lower seal is arranged at the bottom of the insulating sleeve, the grounding sleeve is arranged at the bottom of the lower seal, and the insulating sleeve is filled with insulating oil.
[0014] It can be seen from the above scheme that the oil-filled terminal sleeve is arranged at the end of the cable, and the centering device is arranged in the stress cone, so as to realize the centering of the cable in the stress cone, avoiding the distortion of the internal field strength due to the centering problem of the stress cone, and finally causing the failure. There is a set gap between the insulating sleeve and the outer wall of the stress cone to ensure the circulation of the insulating oil so that the insulating oil is evenly distributed.
[0015] The stress cone includes a stress cone portion and a stress cone shed integrally arranged at the bottom of the stress cone portion, a concave cavity is formed between the stress cone shed and the cable outer shielding layer, the cable centering device is arranged in the concave cavity, the annular flange is connected to the lower sealing member through the connector in the mounting hole, and the cylinder forms a transition fit with the stress cone shed. It can be seen that the annular flange is connected to the lower sealing member to achieve the sealing of the centering device, further ensuring the sealing performance of the oil-filled terminal.
[0016] The lower end of the centering device is provided with a step positioning sleeve, which is formed by wrapping and winding a strip material, and is arranged on the corrugated tube, and the diameter of the step positioning sleeve is smaller than the inner diameter of the centering outer sleeve. It can be seen that the step positioning sleeve is installed at the lower end of the centering device to prevent the centering inner sleeve and the centering block from sliding down after installation, resulting in failure of centering. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 is a schematic diagram of the structure of the cable centering device;
[0018] Figure 2 It is a schematic diagram of the structure of the oil filling terminal;
[0019] Figure 3 yes Figure 2 Schematic diagram of the local structure at A in the middle;
[0020] Figure 4 It is a schematic diagram of the structure of the central inner sleeve;
[0021] Figure 5 It is a schematic diagram of the structure of the center block;
[0022] Figure 6 It is a schematic diagram of the structure of the center jacket. DETAILED DESCRIPTION
[0023] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.
[0024] like Figures 1 to 6 As shown, the utility model provides a cable centering device, which is installed between the cable 100 and the stress cone 6, and is used to keep the cable 100 centered in the stress cone 6. The cable centering device includes a centering inner sleeve 1; a centering block 2, which is sleeved on the centering inner sleeve 1, and the centering block 2 forms an interference fit with the centering inner sleeve 1; and a centering outer sleeve 3, which is sleeved on the centering block 2, and the centering outer sleeve 3 forms an interference fit with the centering block 2.
[0025] A buffer layer is arranged between the cable 100 and the centering inner sleeve 1. The buffer layer is a buffer sleeve 4 formed by wrapping and winding a strip. The centering inner sleeve 1 includes two symmetrically arranged semi-cylinders 11. The inner diameter of the centering inner sleeve 1 is larger than the outer diameter of the cable 100. The centering outer sleeve 3 includes an annular flange 31 and a cylinder 32 integrally and coaxially arranged on the annular flange 31. The diameter of the annular flange 31 is larger than the diameter of the cylinder 32. The inner diameter of the cylinder 32 forms an interference fit with the outer diameter of the centering block 2. The annular flange 31 is provided with a sealing ring groove 311 and a mounting hole 312.
[0026] A plurality of exhaust grooves 21 are arranged on the outer wall of the centering block 2. The exhaust grooves 21 are arranged in a circular array on the outer wall of the centering block 2 along the axial direction of the centering block 2 to facilitate exhaust and later installation. The centering block 2 is integrally formed by stacking a plurality of circular ring blocks 22. The outer wall of the circular ring block 22 is arranged in an arc surface. The edge of the centering block 2 along the axial section is wavy, which reduces the contact area between the outer wall of the centering block 2 and the inner wall of the centering sleeve 3.
[0027] In this embodiment, a through hole is provided on the central axis of the centering outer sleeve 3, the centering outer sleeve 3 is made of aluminum alloy, the thickness of the cylinder 32 is not less than 5 mm, the length of the centering block is guaranteed to be between 120 mm and 150 mm, the centering block 2 is arranged in a circular ring and is made of silicone rubber, the Shore hardness of the centering block 2 is between Shore A50 and 55 degrees, the centering inner sleeve 1 is a cylindrical structure and is made of nylon plastic. The inner diameter of the centering inner sleeve 1 is larger than the outer diameter of the cable outer shielding layer 110, the gap between the inner wall of the centering inner sleeve 1 and the outer wall of the cable outer shielding layer 110 is 8 to 10 mm, the thickness of the centering inner sleeve 1 is not less than 5 mm, and the inner surface of the centering inner sleeve 1 is required to be smooth and without sharp corners to avoid damage to the cable after installation.
[0028] On the other hand, the utility model provides a high-voltage cable oil-filled terminal, which also includes the coaxially arranged stress cone 6, insulating sleeve 7, upper seal 8, lower seal 9 and grounding sleeve 10, the cable 100 includes a cable core and a cable outer shielding layer 110 coated on the cable core, the cable core is provided with a corrugated tube 120 at the bottom of the cable outer shielding layer 110, the cable centering device is arranged between the stress cone 6 and the cable outer shielding layer 110, the insulating sleeve 7 is sleeved on the stress cone 6, and there is a set gap between the outer wall of the stress cone 6 and the inner wall of the insulating sleeve 7, the upper seal 8 is arranged at the top of the insulating sleeve 7, the lower seal 9 is arranged at the bottom of the insulating sleeve 7, the grounding sleeve 10 is arranged at the bottom of the lower seal 9, and the insulating sleeve 7 is filled with insulating oil 11. In this embodiment, the upper seal 8 and the lower seal 9 realize the sealing of the end of the insulating sleeve 7, the grounding sleeve 10 is used for grounding, and the corrugated tube 120 is a tube body formed by spiral bending of aluminum wire.
[0029] The stress cone 6 includes a stress cone portion 61 and a stress cone shed 62 integrally arranged at the bottom of the stress cone portion 61. The stress cone 6 is provided with a concave cavity 63 inside the stress cone shed 62. The cable centering device is arranged in the concave cavity 63. The annular flange 31 is connected to the lower seal 9 through a connector in the mounting hole 312. The cylinder 32 forms a transition fit with the stress cone shed 62. In this embodiment, the upper part of the cylinder 32 extends into the concave cavity 63, and the outer wall of the cylinder 32 forms a transition fit with the stress cone shed 62, so that the cable centering device can achieve flexible sealing and fixing of the stress cone 6. The annular flange 21 is fixed to the lower seal 9 to achieve the position limitation of the cable centering device.
[0030] The working process of the utility model is as follows: the buffer sleeve 4 adapted to the inner wall diameter of the center inner sleeve 1 is formed by winding a tape on the outer wall of the cable outer shielding layer 110, the step positioning sleeve 5 is formed by winding a tape on the cable corrugated tube 120 at the bottom of the cable outer shielding layer 110, the two semi-cylinders 11 of the center inner sleeve 1 are respectively sleeved on the buffer layer 4, the two semi-cylinders 11 are fixed with adhesive tape so that the center inner sleeve 1 is tightly matched with the buffer layer 4, the annular flange 31 of the center outer sleeve 3 is facing downward, and it is sleeved from the end of the cable 100 downward, and the outer wall and inner wall of the center block 2 are smeared. Insulating lubricating oil, then push the centering block 2 into the gap between the centering inner sleeve 1 and the centering outer sleeve 3, push the stress cone 6 downward from the top of the cable 100 until the stress cone portion 61 contacts the top of the centering outer sleeve 3, and at the same time, the stress cone skirt 62 forms a transition fit with the outer wall of the semi-cylinder 11, install an insulating sleeve 7 on the outside of the cable 100 and the stress cone 6, and install the upper seal 8 and the lower seal 9 at both ends of the cable 100, respectively, fix the annular flange 31 with the lower seal 9, and fill the insulating sleeve 7 with insulating oil. The cable centering device of the utility model realizes the centering of the stress cone sleeve on the cable, and the high-voltage cable oil-filled terminal of the utility model solves the electrical insulation problem of the cable end, and at the same time ensures that the stress cone position inside the insulating sleeve of the cable is guaranteed to be centered during the operation of the cable, so that the performance of the high-voltage cable outdoor terminal is more reliable.
[0031] Finally, it should be emphasized that the above is not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A cable centering device, installed between the cable (100) and the stress cone (6), for keeping the cable (100) centered in the stress cone (6), characterized in that: The cable centering device comprises a centering inner sleeve (1); A centering block (2), wherein the centering block (2) is sleeved on the centering inner sleeve (1), and the centering block (2) and the centering inner sleeve (1) form an interference fit; A centering jacket (3), wherein the centering jacket (3) is sleeved on the centering block (2), and the centering jacket (3) and the centering block (2) form an interference fit.
2. The cable centering device according to claim 1, characterized in that: A buffer layer is provided between the cable (100) and the central inner sleeve (1), and the buffer layer is a buffer sleeve (4) formed by wrapping and winding a tape.
3. The cable centering device according to claim 2, characterized in that: The central inner sleeve (1) comprises two semi-cylinders (11) which are symmetrically arranged, and the inner diameter of the central inner sleeve (1) is greater than the outer diameter of the cable (100).
4. The cable centering device according to claim 3, characterized in that: The centering sleeve (3) comprises an annular flange (31) and a cylinder (32) integrally and coaxially arranged on the annular flange (31); the diameter of the annular flange (31) is greater than the diameter of the cylinder (32); the inner diameter of the cylinder (32) forms an interference fit with the outer diameter of the centering block (2); and the annular flange (31) is provided with a sealing ring groove (311) and a mounting hole (312).
5. The cable centering device according to claim 4, characterized in that: A plurality of exhaust grooves (21) are arranged on the outer wall of the centering block (2), and the exhaust grooves (21) are arranged in a circular array on the outer wall of the centering block (2) along the axial direction of the centering block (2). The centering block (2) is integrally formed by stacking a plurality of circular ring blocks (22), and the outer wall of the circular ring block (22) is arranged in an arc surface. The edge of the centering block (2) along the axial section is wavy.
6. The cable centering device according to claim 5, characterized in that: The centering block (2) is made of silicone rubber, and the Shore hardness of the centering block (2) is between Shore A50 and 55 degrees. The centering inner sleeve (1) is made of nylon plastic.
7. A high voltage cable oil-filled terminal comprising the cable centering device according to any one of claims 4 to 6, characterized in that: The high-voltage cable oil-filled terminal also includes the coaxially arranged stress cone (6), the insulating sleeve (7), the upper seal (8), the lower seal (9) and the grounding sleeve (10); the cable (100) includes a cable core and a cable outer shielding layer (110) coated on the cable core; the cable core is provided with a corrugated tube (120) at the bottom of the cable outer shielding layer (110); the cable centering device is arranged between the stress cone (6) and the cable outer shielding layer (110); the insulating sleeve (7) is sleeved on the stress cone (6); there is a set gap between the outer wall of the stress cone (6) and the inner wall of the insulating sleeve (7); the upper seal (8) is arranged at the top end of the insulating sleeve (7); the lower seal (9) is arranged at the bottom of the insulating sleeve (7); the grounding sleeve (10) is arranged at the bottom of the lower seal (9); and the insulating sleeve (7) is filled with insulating oil (11).
8. The high voltage cable oil-filled terminal according to claim 7, characterized in that: The stress cone (6) comprises a stress cone portion (61) and a stress cone shed (62) integrally arranged at the bottom of the stress cone portion (61); the cable centering device is arranged between the stress cone shed (62) and the cable (100); the annular flange (31) is connected to the lower sealing member (9) via a connecting member in the mounting hole (312); and the cylinder (32) and the stress cone shed (62) form a transition fit.
9. The high voltage cable oil-filled terminal according to claim 7, characterized in that: A step positioning sleeve (5) is provided at the lower end of the centering device. The step positioning sleeve (5) is formed by wrapping and winding a strip. The step positioning sleeve (5) is provided on the corrugated tube (120). The diameter of the step positioning sleeve (5) is smaller than the inner diameter of the centering outer sleeve (3).