Limiting protection device, overhead ground wire hardware and discharge gap heating protection method
Patent Information
- Application Number
- CN202611099073.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-23
- Publication Date
- 2026-10-27
AI Technical Summary
在长期运行过程中，受风振、气温波动及材料时效等因素影响，该螺纹连接结构易产生磨损与松动，进一步加剧电极位置的不可控偏移
本申请提出的限位保护装置安装于架空地线绝缘子，用于防止架空地线绝缘子放电间隙发热，限位保护装置包括基体、第一弹性夹持体和第二弹性夹持体，通过第一弧形部、第二弧形部和第三弧形部在扣合状态下共同围合形成限位容纳腔，且限位容纳腔的内径分别小于或等于上放电杆和下放电杆的外径，从而在扣合后能够与两根放电杆的外壁形成紧密贴合。这种过盈配合式的夹持结构，使得当架空地线绝缘子因长期风振、导线舞动或热胀冷缩等因素导致上放电杆或下放电杆发生轴向窜动、径向偏摆或松脱时，限位容纳腔能够持续约束二者的相对位置，强制维持其间的设计间隔，避免因位移造成的放电间隙异常缩小甚至直接接触，可有效阻断短路电流或持续电弧产生的热通路，从根源上防止放电杆接触点因电阻剧增而引发的发热、烧蚀乃至熔焊现象，显著降低了因间隙失效而导致的线路跳闸或设备损坏风险。
Smart Images
Figure CN122992569A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of discharge gap heating protection technology for overhead ground wire insulators, and more specifically, to a limit protection device, overhead ground wire fittings, and discharge gap heating protection method. Background Technology
[0002] Currently, overhead ground wire insulators with external parallel gaps are widely used in suspended lightning protection wires. This type of ground wire insulator typically consists of insulator elements and discharge gaps installed on them. Its core function is to form an insulating barrier between the ground wire and the tower, thereby reducing energy loss of the ground wire and discharging overvoltage.
[0003] In actual operation, the discharge gap exposed to the atmosphere is subject to long-term exposure to natural factors such as alternating hot and cold temperatures and wind and rain erosion, which can easily lead to loosening and displacement defects of the upper and lower electrodes. From a structural design perspective, the main problems are reflected in the following two aspects: Firstly, the upper electrode is clamped and fixed to the outer circumference of the steel cap using a clamp. However, due to the semi-circular shape and irregular surface of the steel cap, the clamp and the steel cap only form point contact, resulting in uneven distribution of clamping force and poor fastening effect. Once the semi-circular clamp becomes slightly loose, the upper electrode may undergo circumferential displacement around the center of the steel cap, thereby changing the original gap orientation.
[0004] Secondly, the lower electrode is fixed to a single flat steel foot below the insulator via a threaded electrode rod. During long-term operation, this threaded connection structure is prone to wear and loosening due to factors such as wind vibration, temperature fluctuations, and material aging, further exacerbating the uncontrollable displacement of the electrode position.
[0005] Both of the above situations may lead to a reduction in the discharge gap between the upper and lower electrodes, resulting in insufficient spacing and electrode overlap, causing localized heating. In severe cases, continuous discharge and arcing may even occur, significantly increasing the risk to the safe operation of the transmission line.
[0006] Therefore, there is an urgent need for a technical solution that can effectively prevent insufficient spacing and overheating caused by loose discharge gaps, so as to improve the reliability and safety of line operation. Summary of the Invention
[0007] In order to solve at least one of the above-mentioned technical problems, the first aspect of this application proposes a limit protection device.
[0008] The second aspect of this application proposes an overhead ground wire fitting.
[0009] The third aspect of this application proposes a method for protecting against overheating in a discharge gap.
[0010] In view of this, the first aspect of this application proposes a limiting protection device, installed on an overhead ground wire insulator. The overhead ground wire insulator includes an upper electrode, a lower electrode, an upper discharge rod connected to the upper electrode, and a lower discharge rod connected to the lower electrode. The device includes: a base having a first arc-shaped portion; a first elastic clamping body having a second arc-shaped portion at one end, the second arc-shaped portion being connected to one end of the first arc-shaped portion, and a snap-fit portion at the other end of the first elastic clamping body; and a second elastic clamping body having a third arc-shaped portion at one end, the third arc-shaped portion being hinged to the other end of the first arc-shaped portion. The other end of the body is provided with a press-type buckle; the press-type buckle engages with the snap-fit part, so that the first elastic clamping body and the second elastic clamping body are snapped together, and the first arc-shaped part, the second arc-shaped part and the third arc-shaped part together form a limiting cavity for accommodating the upper discharge rod and the lower discharge rod; the inner diameter of the limiting cavity is less than or equal to the outer diameter of the upper discharge rod and the outer diameter of the lower discharge rod, so that the limiting cavity fits against the outer wall of the upper discharge rod and the lower discharge rod in the snapped state, and maintains physical isolation between the upper discharge rod and the lower discharge rod when the upper discharge rod or the lower discharge rod becomes loose.
[0011] In conjunction with the first aspect, in some feasible ways, the substrate, the first elastic clamping body, and the second elastic clamping body are integrally molded silicone parts.
[0012] In conjunction with the first aspect, in some feasible methods, the snap-fit part is an L-shaped snap-fit part, which includes a long side and a short side that are connected to each other, and the push-button buckle is a strip-shaped push-button buckle, the end of which is used to snap onto the connection between the long side and the short side.
[0013] In conjunction with the first aspect, in some feasible embodiments, the limit protection device further includes: a pressing part disposed on the side of the long side away from the pressing buckle, and the number of pressing parts is multiple, with the multiple pressing parts spaced apart along the extension direction of the long side.
[0014] In conjunction with the first aspect, in some feasible ways, the inner walls of the first arc-shaped portion, the second arc-shaped portion, and the third arc-shaped portion are respectively provided with anti-slip ridges or anti-slip textures.
[0015] In conjunction with the first aspect, in some feasible embodiments, the limit protection device further includes: a first reinforcing rib arranged circumferentially along the outer wall of the second arcuate portion; and a second reinforcing rib arranged circumferentially along the outer wall of the third arcuate portion.
[0016] In conjunction with the first aspect, in some feasible embodiments, the limiting protection device further includes: a limiting boss disposed on the inner wall of the limiting receiving cavity, the limiting boss protruding radially inward from the inner wall of the limiting receiving cavity.
[0017] In conjunction with the first aspect, in some feasible embodiments, the limiting protection device further includes: a sealing structure disposed at the ports at both axial ends of the limiting receiving cavity; the sealing structure includes an elastic sealing lip that extends from the inner wall of the limiting receiving cavity toward the axial direction of the limiting receiving cavity and elastically abuts against the outer walls of the upper discharge rod and the lower discharge rod in the engaged state to form an annular seal at the ports of the limiting receiving cavity.
[0018] The second aspect of this application proposes an overhead ground wire fitting, including: a limit protection device as described in any of the above technical solutions.
[0019] A third aspect of this application proposes a method for protecting against overheating in a discharge gap, employing a limit protection device as described in any of the above technical solutions, comprising the following steps: The limit protection device is sleeved on the upper discharge rod and the lower discharge rod, so that the upper discharge rod and the lower discharge rod are respectively placed on the second arc-shaped part of the first elastic clamping body; Adjust the axial position of the limit protection device on the upper and lower discharge rods, and adjust the distance between the upper and lower discharge rods so that the limit protection device is located between the upper and lower discharge rods; The locking and limiting protection device engages with the snap-on buckle and the locking part, and the limiting cavity fits against the outer walls of the upper and lower discharge rods, maintaining physical isolation between them when the upper or lower discharge rod becomes loose.
[0020] Compared with related technologies, this application has the following technical advantages: The limiting protection device proposed in this application is installed on an overhead ground wire insulator to prevent the discharge gap of the overhead ground wire insulator from heating up. The limiting protection device includes a base, a first elastic clamping body and a second elastic clamping body. The first arc-shaped part, the second arc-shaped part and the third arc-shaped part together form a limiting cavity when they are engaged. The inner diameter of the limiting cavity is less than or equal to the outer diameter of the upper discharge rod and the lower discharge rod, respectively, so that it can fit tightly with the outer wall of the two discharge rods after being engaged. This interference fit clamping structure ensures that when the overhead ground wire insulator experiences axial movement, radial sway, or loosening of the upper or lower discharge rod due to long-term wind vibration, conductor galloping, or thermal expansion and contraction, the limiting cavity can continuously constrain the relative position of the two, forcibly maintaining the designed gap between them. This prevents abnormal shrinkage of the discharge gap or even direct contact caused by displacement, effectively blocking the thermal path generated by short-circuit current or continuous arc. It fundamentally prevents heating, burning, and even welding phenomena caused by a surge in resistance at the discharge rod contact point, significantly reducing the risk of line tripping or equipment damage due to gap failure.
[0021] In practical applications, this limit protection device effectively avoids discharge gap reduction and electrode overlap problems caused by loose ground wire insulators, significantly reducing manual troubleshooting time and improving the operational safety of transmission lines. Simultaneously, the device effectively prevents overheating or arcing of the discharge gap after insulator loosening, resulting in a significant efficiency improvement for daily operation and maintenance of transmission lines.
[0022] Additional aspects and advantages of this application will become apparent in the following description or may be learned by practice of this application. Attached Figure Description
[0023] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 One of the structural schematic diagrams of the limiting protection device in one embodiment of this application is shown; Figure 2 A second schematic diagram of the structure of the limit protection device in one embodiment of this application is shown; Figure 3 The third schematic diagram of the limit protection device in one embodiment of this application is shown; Figure 4 A schematic diagram showing the installation state of the limit protection device in one embodiment of this application is illustrated; Figure 5 A schematic diagram of the overhead grounding wire fitting in one embodiment of this application is shown; Figure 6 A schematic flowchart of a discharge gap overheating protection method according to one embodiment of this application is shown.
[0024] in, Figures 1 to 5 The correspondence between the reference numerals and component names in the attached drawings is as follows: 100 Limit protection device, 110 Upper discharge rod, 112 Lower discharge rod, 120 Base, 122 First arc-shaped part, 130 First elastic clamping body, 132 Second arc-shaped part, 134 Snap-fit part, 136 Pressing part, 140 Second elastic clamping body, 142 Third arc-shaped part, 146 Press-type buckle, 150 Sealing structure, 200 Overhead ground wire hardware, 210 First U-shaped hanging ring, 212 Extension ring, 214 Second U-shaped hanging ring, 216 Connecting plate, 218 Parallel scraper, 220 Overhead ground wire insulator, 222 Hanging plate, 224 Ground wire tension clamp, 226 Equipment clamp. Detailed Implementation
[0025] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.
[0026] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.
[0027] The following reference Figures 1 to 6 This application describes a limit protection device, an overhead ground wire fitting, and a method for preventing overheating of a discharge gap according to some embodiments.
[0028] like Figure 1 , Figure 4 and Figure 5 As shown, the first aspect of this application proposes a limiting protection device 100, installed on an overhead ground wire insulator 220. The overhead ground wire insulator 220 includes an upper electrode, a lower electrode, an upper discharge rod 110 connected to the upper electrode, and a lower discharge rod 112 connected to the lower electrode. The device includes: a base 120 with a first arcuate portion 122; a first elastic clamping body 130 with a second arcuate portion 132 at one end, the second arcuate portion 132 being connected to one end of the first arcuate portion 122, and a snap-fit portion 134 at the other end; and a second elastic clamping body 140 with a third arcuate portion 142 at one end, the third arcuate portion 142 being hinged to the other end of the first arcuate portion 122. The other end is provided with a press-type buckle 146; the press-type buckle 146 engages with the snap-fit part 134, so that the first elastic clamping body 130 and the second elastic clamping body 140 are snapped together, and the first arc-shaped part 122, the second arc-shaped part 132 and the third arc-shaped part 142 together form a limiting cavity for accommodating the upper discharge rod 110 and the lower discharge rod 112; the inner diameter of the limiting cavity is less than or equal to the outer diameter of the upper discharge rod 110 and the outer diameter of the lower discharge rod 112, so that the limiting cavity fits against the outer wall of the upper discharge rod 110 and the lower discharge rod 112 in the snapped state, and maintains physical isolation between the upper discharge rod 110 and the lower discharge rod 112 when the upper discharge rod 110 or the lower discharge rod 112 becomes loose.
[0029] The limiting protection device 100 proposed in this application is installed on the overhead ground wire insulator 220. The limiting protection device 100 includes a base 120, a first elastic clamping body 130 and a second elastic clamping body 140. The first arc-shaped part 122, the second arc-shaped part 132 and the third arc-shaped part 142 together form a limiting cavity when they are engaged. The inner diameter of the limiting cavity is less than or equal to the outer diameter of the upper discharge rod 110 and the lower discharge rod 112, respectively, so that it can fit tightly with the outer wall of the two discharge rods after being engaged. This interference fit clamping structure ensures that when the overhead ground wire insulator 220 experiences axial movement, radial sway, or loosening of the upper discharge rod 110 or lower discharge rod 112 due to long-term wind vibration, conductor galloping, or thermal expansion and contraction, the limiting cavity can continuously constrain the relative position of the two, forcibly maintaining the designed gap between them. This prevents abnormal shrinkage of the discharge gap or even direct contact caused by displacement, effectively blocking the thermal path generated by short-circuit current or continuous arc. It fundamentally prevents the discharge rod contact point from heating, burning, or even welding caused by a surge in resistance, significantly reducing the risk of line tripping or equipment damage due to gap failure.
[0030] The first elastic clamp 130 and the second elastic clamp 140 are assembled by a quick-locking method using a press-type buckle 146 and a locking part 134. Furthermore, the connection between the second arc-shaped part 132 and one end of the first arc-shaped part 122, and the hinge connection between the third arc-shaped part 142 and the other end of the first arc-shaped part 122, form an openable cylindrical structure. This allows for direct on-site installation on existing lines without disassembling or modifying the original upper discharge rod 110, lower discharge rod 112, or electrode structure, avoiding drilling, welding, or bonding operations and preserving the original electrical parameters and mechanical layout of the discharge gap. Simultaneously, the press-type buckle 146 facilitates opening and repeated locking by maintenance personnel, providing operational convenience for daily inspections, gap measurements, and subsequent maintenance, demonstrating excellent engineering adaptability and maintainability.
[0031] Through the combined effect of the aforementioned physical limiting and rapid installation functions, this protection device effectively solves the problem of gap drift caused by mechanical loosening during long-term operation of traditional discharge gaps, reduces the frequency of unplanned power outages, and improves the operational safety and stability of transmission lines under adverse weather conditions and complex terrain.
[0032] In some embodiments provided in this application, the substrate 120, the first elastic clamping body 130, and the second elastic clamping body 140 are integrally molded silicone parts.
[0033] In this embodiment, the substrate 120, the first elastic clamping body 130, and the second elastic clamping body 140 are integrally molded silicone parts. The silicone material possesses both excellent elasticity and flexibility, allowing the limiting and receiving cavity to fit tightly against the outer walls of the upper discharge rod 110 and the lower discharge rod 112, while preventing damage to the rod surface due to excessive rigidity. Furthermore, silicone itself is an insulating material, which will not interfere with the original electric field distribution of the discharge gap, and it possesses resistance to high and low temperatures, ultraviolet radiation, and ozone aging, making it suitable for harsh climatic conditions.
[0034] The unibody structure eliminates the mechanical clearances, wear, and corrosion risks associated with traditional hinged or connected parts, improving reliability and weather resistance for long-term outdoor operation. Furthermore, the integrated injection molding process simplifies the production and assembly process, reduces manufacturing costs, lightens the device's weight, and facilitates quick installation and disassembly by a single person on-site.
[0035] like Figure 1 As shown, in some embodiments provided in this application, the snap-fit portion 134 is an L-shaped snap-fit portion, which includes a long side portion and a short side portion connected to each other, and the push-button buckle 146 is a strip-shaped push-button buckle, the end of which is used to snap onto the connection between the long side portion and the short side portion.
[0036] In this embodiment, the latching part 134 is an L-shaped latching part, and the press-type buckle 146 is a strip-shaped press-type buckle. The long side and short side of the L-shaped latching part form a corner limit. After the end of the strip-shaped press-type buckle is inserted into the connection, it is subject to dual longitudinal and lateral constraints, effectively resisting the impact forces caused by line wind vibration and galloping, preventing the buckle from slipping and coming off, ensuring that the limiting cavity always tightly clamps the upper discharge rod 110 and the lower discharge rod 112, maintaining the continuous reliability of physical isolation, and significantly improving the vibration resistance and anti-disengagement capability of the buckled state.
[0037] like Figure 2 and Figure 3 As shown, in some embodiments provided in this application, the limiting protection device 100 further includes: a pressing part 136, which is disposed on the side of the long side away from the pressing buckle 146. There are multiple pressing parts 136, and the multiple pressing parts 136 are spaced apart along the extension direction of the long side.
[0038] In this embodiment, the limit protection device 100 also includes a plurality of pressing parts 136. The plurality of pressing parts 136 are spaced apart along the long side, providing maintenance personnel with multiple points of force application. Appropriate pressing points can be selected according to operating habits or space constraints, effectively improving the convenience of one-handed locking and unlocking and reducing the risk of misoperation.
[0039] The pressing part 136 is located on the side of the long side away from the buckle. When force is applied, it acts directly on the long side, avoiding the force from being transmitted to the end of the buckle and causing deformation, thus ensuring the stability of the snap-fit position. The spaced arrangement of pressing force reduces local fatigue and extends the service life of the device.
[0040] In some embodiments provided in this application, the inner walls of the first arc-shaped portion 122, the second arc-shaped portion 132 and the third arc-shaped portion 142 are respectively provided with anti-slip ridges or anti-slip textures.
[0041] In this embodiment, anti-slip ridges or anti-slip textures are provided on the inner walls of the three arc-shaped parts, which can increase the static friction between the discharge rod and the outer wall of the discharge rod. This effectively prevents the axial movement and radial rotation of the discharge rod caused by line vibration, wire dancing or thermal expansion and contraction, and ensures that the limiting cavity always maintains a tight hold on the upper discharge rod 110 and the lower discharge rod 112 in the locked state. This maintains the design accuracy of the discharge gap for a long time and avoids electrical faults caused by gap drift.
[0042] Meanwhile, the anti-slip structure can disperse local stress on the contact surface, prevent the silicone from sticking or creeping with the smooth rod due to long-term static contact, reduce the adhesion resistance during disassembly, and facilitate daily inspection and disassembly; the micro-protrusions can also compensate for the fitting gap caused by manufacturing tolerances or slight wear, and enhance the adaptability of the device to different rod diameter tolerances.
[0043] In some embodiments provided in this application, the limiting protection device 100 further includes: a first reinforcing rib disposed circumferentially along the outer wall of the second arcuate portion 132; and a second reinforcing rib disposed circumferentially along the outer wall of the third arcuate portion 142.
[0044] In this embodiment, the limiting protection device 100 further includes a first reinforcing rib and a second reinforcing rib.
[0045] The first and second reinforcing ribs are respectively arranged circumferentially along the outer wall of the second arc-shaped portion 132 and the third arc-shaped portion 142, which significantly enhances the structural rigidity of the arc-shaped portion of the elastic clamping body, prevents radial expansion deformation when clamped for a long time or subjected to vibration load, ensures the dimensional accuracy of the limiting cavity and the continuous stability of the holding force, and maintains reliable clamping of the discharge rod.
[0046] The circumferential reinforcing ribs can also effectively disperse the stress concentration caused by opening and closing operations and external impacts, reduce the risk of fatigue cracking at the root of the arc-shaped part, improve the device's anti-aging and anti-creep capabilities in harsh outdoor environments, extend the overall service life, and reduce the frequency of maintenance and replacement.
[0047] In some embodiments provided in this application, the limiting protection device 100 further includes: a limiting boss disposed on the inner wall of the limiting receiving cavity, the limiting boss protruding radially inward from the inner wall of the limiting receiving cavity.
[0048] In this embodiment, the limiting protection device 100 also includes a limiting boss. The limiting boss protrudes radially inward from the inner wall of the limiting receiving cavity, forming an axial stop engagement with the ends of the upper discharge rod 110 and the lower discharge rod 112. This effectively restrains axial movement caused by wind vibration or thermal expansion and contraction, prevents the rod from coming out or extending into the gap area, and ensures that the upper discharge rod 110 and the lower discharge rod 112 maintain the designed safe distance. This compensates for the shortcomings of simple radial clamping on axial limiting and achieves double locking.
[0049] The limiting boss is integrally molded with the silicone body, requiring no additional parts and reducing assembly complexity. Its protrusion height can be optimized according to the rod's tolerances, ensuring effective limiting while preventing excessive compression and damage to the rod. The boss also serves as an installation positioning mark, assisting maintenance personnel in quickly determining the engagement position and improving on-site operational efficiency.
[0050] like Figure 3 and Figure 4 As shown, in some embodiments provided in this application, the limiting protection device 100 further includes: a sealing structure 150 disposed at the ports at both axial ends of the limiting accommodating cavity; the sealing structure 150 includes an elastic sealing lip, which extends from the inner wall of the limiting accommodating cavity toward the axial direction of the limiting accommodating cavity, and elastically abuts against the outer walls of the upper discharge rod 110 and the lower discharge rod 112 in the engaged state to form an annular seal at the port of the limiting accommodating cavity.
[0051] In this embodiment, the limiting protection device 100 further includes a sealing structure 150, which includes an elastic sealing lip. The sealing structure 150 has elastic sealing lips at both axial ends of the limiting receiving cavity. After engagement, the sealing lips elastically abut against the outer walls of the upper discharge rod 110 and the lower discharge rod 112 to form an annular seal, effectively preventing external environmental media such as rainwater, moisture, salt spray, and dust from intruding into the cavity. This avoids the accumulation of contaminants between the discharge rod and the clamping body, thereby preventing a decrease in insulation performance or abnormal partial discharge due to contamination. Simultaneously, the elastic abutment of the sealing lip and the anti-slip protrusion work synergistically, isolating the external environment without significantly increasing engagement resistance, ensuring smooth installation.
[0052] The elastic sealing lip extends from the inner wall towards the axis, adaptively conforming to the outer wall of the discharge rod with different diameter tolerances within a certain range. Even if the rod has slight ellipticity or surface unevenness, the sealing lip can achieve a reliable fit through local elastic deformation, compensating for gaps caused by manufacturing errors or long-term wear. This sealing structure 150 takes effect simultaneously with the snap-fit action, requiring no additional steps and not increasing installation complexity; moreover, the sealing lip is integrally molded with the silicone body, minimizing the risk of aging and detachment, and continuously providing a stable protective barrier during long-term outdoor operation, effectively ensuring the cleanliness and dryness of the internal environment of the limiting and receiving cavity.
[0053] like Figure 5 As shown, the second aspect of this application proposes an overhead ground wire fitting 200, including: a limit protection device 100 as described in any of the above embodiments.
[0054] The overhead ground wire fitting 200 provided in this application includes the limit protection device 100 in any of the above embodiments, and therefore has all the beneficial effects of the limit protection device 100, which will not be repeated here.
[0055] like Figure 5 As shown, in practical applications, the overhead ground wire hardware 200 also includes a first U-shaped hanging ring 210, an extension ring 212, a second U-shaped hanging ring 214, a connecting plate 216, a parallel scraper 218, an overhead ground wire insulator 220, a hanging plate 222, a ground wire tension clamp 224, and an equipment clamp 226. All components are connected by bolts. Furthermore, a limit protection device 100 is installed on the overhead ground wire insulator 220.
[0056] like Figure 6 As shown, the third aspect of this application proposes a method for protecting against overheating in a discharge gap, employing a limiting protection device as described in any of the above embodiments, comprising the following steps: S302: The limit protection device is sleeved on the upper discharge rod and the lower discharge rod, so that the upper discharge rod and the lower discharge rod are respectively placed on the second arc-shaped part of the first elastic clamping body; S304: Adjust the axial position of the limit protection device on the upper and lower discharge rods, and adjust the distance between the upper and lower discharge rods so that the limit protection device is located between the upper and lower discharge rods; S306: The snap-fit limit protection device makes the push-type buckle engage with the snap-fit part, and the limit receiving cavity fits against the outer wall of the upper and lower discharge rods, and maintains physical isolation between the two when the upper or lower discharge rod becomes loose.
[0057] The discharge gap overheating protection method provided in this application achieves rapid and effective protection against discharge gap overheating through three steps: sleeve installation, axial adjustment, and fastening. In the sleeve installation step, the upper and lower discharge rods are placed on the second arc-shaped part of the first elastic clamp, using the arc shape to initially constrain the rod posture and provide a reference for subsequent precise adjustment. In the adjustment step, the axial position of the device on the rod can be flexibly changed before fastening, and the distance between the upper and lower discharge rods is adjusted accordingly to ensure that the limit protection device is accurately installed at the appropriate position between the upper and lower discharge rods, balancing the electrical distance and mechanical protection requirements of the discharge gap design. The fastening step uses a press-type buckle and an L-shaped locking part to lock in place in one go. The operation is efficient and convenient, requiring no special tools and can be completed by a single person on-site. The entire process is simple and smooth, significantly reducing installation difficulty and time costs, and is particularly suitable for field operations on transmission lines, significantly improving construction efficiency and personnel safety.
[0058] After engagement, the limiting cavity fits tightly against the outer wall of the discharge rod. Thanks to the combined effect of the device's structural rigidity and anti-slip protrusions and limiting bosses, even under long-term exposure to alternating loads from wind vibration, galloping, or thermal expansion and contraction, it continuously constrains the relative positions of the upper and lower discharge rods. If either rod shows signs of loosening, it forcibly maintains physical isolation between them, fundamentally blocking abnormal heating and arc erosion pathways caused by gap contact or excessive proximity. Simultaneously, this protection method completely preserves the original electrical structure and parameters of the discharge gap, and installation and disassembly do not damage the rod surface. Regular inspections, including visual checks of the device's condition and manual opening and closing tests, can quickly determine if there are any potential hazards in the gap.
[0059] like Figures 1 to 5 As shown in the specific embodiment, this application provides a limit protection device 100, installed on the overhead ground wire insulator 220, which can prevent the discharge gap of the overhead ground wire insulator 220 from overheating. Without changing the original structure of the discharge gap, it can effectively avoid overheating faults caused by insufficient gap distance or electrode overlap, thereby improving the safety of line operation and having practical application value for the operation and maintenance of transmission lines.
[0060] Analysis of the causes of discharge gap heating indicates that existing methods are insufficient to address wear and loosening caused by equipment aging, quality defects, or long-term operation. Loosening can easily lead to insufficient gap distance or electrode overlap. Furthermore, traditional fastening structures cannot withstand long-term environmental and mechanical vibrations, thus the risk of loosening objectively exists.
[0061] The technical solution adopted in this application is as follows: by physically isolating the discharge gap, its normal discharge function is not affected, and problems such as insufficient gap or overlap caused by loosening are effectively prevented. This method fills the gap in the current lack of targeted prevention and control measures and has clear rationality and practicality.
[0062] Specifically, the lower electrode is fixed to a single flat steel foot, and the upper electrode is fixed by a clamp at the end of a slotted iron cap. The gap between the upper and lower electrodes is adjusted by rotating the clamp at the end of the slotted iron cap during line construction and installation. To prevent fatigue loosening of the clamp and discharge gap rod bolts due to wind swaying, vibration, etc., a limit protection device 100 is installed on the discharge gap rod. This device acts as a physical isolation device, ensuring that even if the gap rod loosens, the discharge gap distance will not be insufficient. The discharge gap rod corresponds to the upper discharge rod 110 and the lower discharge rod 112.
[0063] The material for this limiting device needs to possess properties such as insulation, wear resistance, and resistance to aging. Tests show that while glass fiber reinforced plastic (GFRP) has high hardness, good insulation, and some wear resistance, its cost is high, and its flexibility and adhesion when in contact with metal parts are poor, making it prone to slippage and detachment. In contrast, silicone has better flexibility and adhesion, effectively solving the slippage and detachment problem. Therefore, silicone was ultimately selected as the material for the limiting protection device 100 in this design.
[0064] The limit protection device 100 is made of silicone and uses a hinge structure to securely cover and fix the discharge gap rod. The snap-fit design facilitates quick installation and removal, ensuring reliable fixation while also providing operational flexibility and convenience. This allows workers to safely and smoothly complete installation and maintenance work on the tower. This device effectively ensures the safe and stable operation of the insulator discharge gap assembly, providing reliable protection for the overhead ground wire.
[0065] This application, by setting a limit protection device 100, effectively avoids problems such as insufficient discharge gap spacing and electrode overlap caused by loose ground wire insulators in practical applications, while eliminating the resulting risks of overheating or sparking. This device significantly reduces the time required for manual tower repairs, substantially improving the operational safety and maintenance efficiency of transmission lines.
[0066] This limit protection device is easy to install and inexpensive, and provides reliable limit protection for the discharge gap rod of the ground wire insulator in ultra-high voltage transmission lines, making it highly valuable for widespread application. As of December 2025, more than 2,000 of these devices have been installed on over 500 towers maintained by the State Grid Hebei Ultra-High Voltage Branch, achieving limited-scale application.
[0067] In terms of indirect economic benefits, compared with the traditional manual tower-climbing repair method, using this device can save approximately 2 days of time for troubleshooting discharge gap overheating during each maintenance. Based on an average transmission load of 1000MW for a 500kV line and a grid-crossing power loss cost of 0.07 yuan / kWh, a single maintenance can reduce power loss by approximately 3.36 million yuan. When carrying the device, place it in a dedicated work bag to avoid heavy pressure and bending. When working on the tower, take out the device and fix it in a suitable position in the discharge gap. Press the buckle firmly until it is fully locked, and the main body of the device can effectively ensure the discharge gap distance.
[0068] In this application, the term "multiple" refers to two or more unless otherwise expressly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0069] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0070] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A limit protection device, installed on an overhead ground wire insulator, the overhead ground wire insulator comprising an upper electrode, a lower electrode, an upper discharge rod connected to the upper electrode, and a lower discharge rod connected to the lower electrode, characterized in that, include: The base has a first arc-shaped portion; The first elastic clamping body has a second arc-shaped portion at one end, the second arc-shaped portion is connected to one end of the first arc-shaped portion, and a snap-fit portion at the other end of the first elastic clamping body. The second elastic clamping body has a third arc-shaped part at one end, which is hinged to the other end of the first arc-shaped part, and the other end of the second elastic clamping body has a press-type buckle. The press-type buckle engages with the snap-fit part, causing the first elastic clamping body and the second elastic clamping body to snap together. The first arc-shaped part, the second arc-shaped part, and the third arc-shaped part together form a limiting cavity for accommodating the upper discharge rod and the lower discharge rod. The inner diameter of the limiting cavity is less than or equal to the outer diameter of the upper discharge rod and the outer diameter of the lower discharge rod, respectively, so that the limiting cavity fits against the outer walls of the upper discharge rod and the lower discharge rod in the snap-fit state, and maintains physical isolation between the upper discharge rod and the lower discharge rod when the upper discharge rod or the lower discharge rod becomes loose.
2. The limit protection device according to claim 1, characterized in that, The substrate, the first elastic clamping body, and the second elastic clamping body are integrally molded silicone parts.
3. The limit protection device according to claim 1, characterized in that, The latching part is an L-shaped latching part, which includes a long side and a short side that are connected to each other. The push-button buckle is a strip-shaped push-button buckle, and the end of the strip-shaped push-button buckle is used to latch onto the connection between the long side and the short side.
4. The limit protection device according to claim 3, characterized in that, Also includes: A pressing part is provided on the side of the long side that is away from the pressing buckle. There are multiple pressing parts, and the multiple pressing parts are spaced apart along the extension direction of the long side.
5. The limit protection device according to claim 1, characterized in that, The inner walls of the first arc-shaped portion, the second arc-shaped portion, and the third arc-shaped portion are respectively provided with anti-slip ridges or anti-slip textures.
6. The limit protection device according to claim 1, characterized in that, Also includes: The first reinforcing rib is provided circumferentially along the outer wall of the second arc-shaped portion; The second reinforcing rib is provided circumferentially along the outer wall of the third arc-shaped portion.
7. The limit protection device according to claim 1, characterized in that, Also includes: A limiting boss is disposed on the inner wall of the limiting receiving cavity, and the limiting boss protrudes radially inward from the inner wall of the limiting receiving cavity.
8. The limit protection device according to claim 1, characterized in that, Also includes: A sealing structure is provided at the ports at both axial ends of the limiting and receiving cavity; The sealing structure includes an elastic sealing lip that extends from the inner wall of the limiting cavity toward the axis of the limiting cavity and elastically abuts against the outer walls of the upper discharge rod and the lower discharge rod in the engaged state to form an annular seal at the port of the limiting cavity.
9. An overhead grounding wire fitting, characterized in that, include: The limiting protection device as described in any one of claims 1 to 8.
10. A method for protecting against overheating in a discharge gap, characterized in that, The limit protection device as described in any one of claims 1 to 8 includes the following steps: The limiting protection device is sleeved on the upper discharge rod and the lower discharge rod, so that the upper discharge rod and the lower discharge rod are respectively placed on the second arc-shaped part of the first elastic clamping body; Adjust the axial position of the limiting protection device on the upper discharge rod and the lower discharge rod, and adjust the distance between the upper discharge rod and the lower discharge rod so that the limiting protection device is located between the upper discharge rod and the lower discharge rod; The limiting protection device is fastened so that the press-type buckle engages with the locking part, the limiting receiving cavity fits against the outer wall of the upper discharge rod and the lower discharge rod, and maintains physical isolation between the two when the upper discharge rod or the lower discharge rod becomes loose.