Composite insulator
By setting a multi-layer sheath and a maze structure on the connection part of the mandrel and the metal component of the composite insulator, the problem of poor moisture resistance is solved, and effective water vapor barrier and long-term and stable operation of the mandrel is achieved.
Patent Information
- Application Number
- CN202420689298.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-03
- Publication Date
- 2025-05-13
- Estimated Expiration
- 2034-04-03
AI Technical Summary
The existing composite insulators have poor moisture resistance and cannot effectively prevent water vapor from invading the core rod, resulting in problems such as rotten rot and string loss during long-term operation.
A composite insulator is designed, and a first sheath layer covers the core rod, and a second sheath layer covers the connection part of the metal member, and a maze structure and groove are provided at the connection part to form a sealing fit to prevent water vapor from invasion.
Through the primary and secondary water blocking mechanisms, the moisture resistance of the composite insulator is significantly improved, and water vapor intrusion is prevented, thereby extending the service life of the core rod.
Smart Images
Figure CN222867342U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of insulators, in particular to a composite insulator. Background Art
[0002] In recent years, drones have found that composite insulators are generally overheated during inspections of power transmission lines, and composite insulators that have been in operation for about 15 years have problems such as core rod decay and string loss. In addition to the characteristics of the core rod and silicone rubber itself, these problems are also related to the structure of the end connection hardware, the umbrella sleeve forming process, and the interface bonding performance between the core rod and the sheath. At present, the existing composite insulator end hardware generally adopts an end face groove structure to increase the sealing effect, but the side sealing effect of the end hardware is poor, the moisture resistance is poor, and it is impossible to avoid water vapor intrusion into the core rod during long-term operation. Utility Model Content
[0003] The main purpose of the utility model is to provide a composite insulator, which can solve the problem that the existing composite insulator has poor moisture resistance and cannot avoid water vapor intrusion into the core rod during long-term operation.
[0004] In order to achieve the above-mentioned purpose, the utility model provides a composite insulator, comprising: a core rod; a first sheath layer, which is coated on the outer periphery of the core rod; an umbrella cover, which is coated on the outer periphery of the first sheath layer, and the umbrella cover comprises a second sheath layer and an umbrella skirt located on the outer periphery of the second sheath layer; and a metal structure, which is sleeved on the end of the core rod, the metal structure comprises a metal component, the metal component comprises a connecting part located at the end of the metal component, a labyrinth structure is arranged on the connecting part, a groove is arranged on the outer peripheral wall of the connecting part, the second sheath layer is coated on the outer periphery of the connecting part, a protrusion matched with the groove is arranged on the second sheath layer, and the protrusion forms a sealing fit with the groove.
[0005] Furthermore, the protrusion and the groove are interference fit.
[0006] Furthermore, there are multiple grooves and protrusions, the multiple grooves are arranged at intervals along the length direction of the core rod, and the multiple protrusions are arranged in a one-to-one correspondence with the multiple grooves.
[0007] Further, the labyrinth structure includes a convex portion and a concave portion, and the second sheath layer can be adapted to both the convex portion and the concave portion and form a sealing fit with the convex portion and the concave portion.
[0008] Furthermore, there are multiple convex portions and multiple concave portions, and the multiple convex portions and the multiple concave portions are arranged alternately.
[0009] Furthermore, the metal structure also includes an annular member, which is sleeved on the outer circumference of the metal component, the end of the second sheath layer is covered on the outer circumference of the maze structure and the annular member, and one end of the annular member away from the maze structure protrudes from the second sheath layer by a preset distance H1.
[0010] Furthermore, the value range of the preset distance H1 is H1>3mm.
[0011] Furthermore, the second sheath layer and the umbrella skirt are integrally formed, and the first sheath layer and the umbrella cover are made of the same material.
[0012] Furthermore, the thickness of the first sheath layer is H2, the total thickness of the first sheath layer and the second sheath layer is H3, and the value range of H2 / H3 is 1 / 3 to 2 / 5.
[0013] Furthermore, the thickness of the first sheath layer ranges from 0.5 mm to 3.0 mm.
[0014] By applying the technical solution of the utility model, the first sheath layer is coated on the outer periphery of the core rod, which can effectively protect the core rod from being corroded by water vapor and form a primary water barrier. A maze structure is provided on the connecting part of the metal component, and a groove is provided on the outer peripheral wall of the connecting part. The second sheath layer is coated on the outer periphery of the connecting part, and the protrusion of the second sheath layer is embedded in the groove to form a sealing fit, which can further prevent water vapor from penetrating into the core rod from the end position of the metal structure, forming a secondary water barrier and enhancing the sealing effect on the end of the core rod, thereby improving the moisture resistance of the composite insulator. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention.
[0016] In the figure:
[0017] Figure 1 A structural schematic diagram of a composite insulator according to an embodiment of the utility model is shown.
[0018] The above drawings include the following reference numerals:
[0019] 10. core rod; 20. first sheath layer; 30. second sheath layer; 31. protrusion; 40. metal structure; 41. metal component; 42. ring; 50. labyrinth structure; 51. convex part; 52. concave part; 53. connecting part; 60. groove. DETAILED DESCRIPTION
[0020] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0021] like Figure 1As shown, the utility model provides a composite insulator, which includes: a core rod 10; a first sheath layer 20, which is coated on the outer periphery of the core rod 10; an umbrella cover, which is coated on the outer periphery of the first sheath layer 20, and the umbrella cover includes a second sheath layer 30 and an umbrella skirt located on the outer periphery of the second sheath layer 30; and a metal structure 40, which is sleeved on the end of the core rod 10, the metal structure 40 includes a metal component 41, the metal component 41 includes a connecting portion 53 located at the end of the metal component 41, a labyrinth structure 50 is arranged on the connecting portion 53, a groove 60 is arranged on the outer peripheral wall of the connecting portion 53, the second sheath layer 30 is coated on the outer periphery of the connecting portion 53, and a protrusion 31 matched with the groove 60 is arranged on the second sheath layer 30, and the protrusion 31 forms a sealing fit with the groove 60.
[0022] In this embodiment, the outer circumference of the core rod 10 is sequentially coated with a first sheath layer 20 and a second sheath layer 30. The provision of the first sheath layer 20 can effectively protect the core rod 10 from being corroded by water vapor, forming a primary water barrier. A labyrinth structure 50 is provided on the connection portion 53 of the metal component 41, a groove 60 is provided on the outer peripheral wall of the connection portion 53, the second sheath layer 30 is coated on the outer circumference of the connection portion 53, and the protrusion 31 of the second sheath layer 30 is embedded in the groove 60 to form a sealing fit, which can further prevent water vapor from penetrating into the core rod 10 from the end position of the metal structure 40, forming a secondary water barrier, enhancing the sealing effect on the end of the core rod 10, thereby improving the moisture resistance of the composite insulator.
[0023] In one embodiment, the first sheath layer 20 is coated on the outer periphery of the core rod 10 by extrusion molding, with no mold seam on the surface and reliable interface bonding effect, and the umbrella cover is injection molded in sections on the outer periphery of the first sheath layer 20 by an injection machine.
[0024] In one embodiment, the outer peripheral surface of the first sheath layer 20 in contact with the metal structure 40 is polished, and the finish reaches the finish of the umbrella cover surface.
[0025] like Figure 1 As shown, in one embodiment of the present invention, the protrusion 31 and the groove 60 are interference fit.
[0026] Through the above arrangement, the sealing effect can be ensured.
[0027] like Figure 1 As shown, in one embodiment of the present invention, there are multiple grooves 60 and multiple protrusions 31, the multiple grooves 60 are arranged at intervals along the length direction of the core rod 10, and the multiple protrusions 31 are arranged in a one-to-one correspondence with the multiple grooves 60.
[0028] In this embodiment, a plurality of protrusions 31 are arranged in one-to-one correspondence with a plurality of grooves 60, and the protrusions 31 are embedded in the corresponding grooves 60 and form a sealing fit with the grooves 60. Through the above arrangement, the sealing effect on the end of the core rod 10 can be further enhanced.
[0029] like Figure 1 As shown, in one embodiment of the present invention, the labyrinth structure 50 includes a convex portion 51 and a concave portion 52 , and the second sheath layer 30 can be adapted to both the convex portion 51 and the concave portion 52 and form a sealing fit with the convex portion 51 and the concave portion 52 .
[0030] In this embodiment, when the second sheath layer 30 is wrapped around the outer periphery of the connecting portion 53 , both the convex portion 51 and the concave portion 52 of the labyrinth structure 50 can form a sealing fit with the second sheath layer 30 to achieve sealing of the end of the core rod 10 .
[0031] like Figure 1 As shown, in one embodiment of the present invention, there are multiple protrusions 51 and multiple recesses 52, and the multiple protrusions 51 and the multiple recesses 52 are arranged alternately.
[0032] In this embodiment, on the end face of the connecting portion 53, a plurality of protrusions 51 and a plurality of recesses 52 are alternately arranged to form a concave-convex structure. When the second sheath layer 30 is wrapped around the outer periphery of the connecting portion 53, the second sheath layer 30 can form a concave-convex fit with the above-mentioned concave-convex structure, which can not only ensure the connection stability between the metal component 41 and the second sheath layer 30, but also improve the sealing effect on the end of the core rod 10.
[0033] like Figure 1 As shown, in one embodiment of the utility model, the metal structure 40 also includes an annular member 42, which is sleeved on the outer periphery of the metal component 41, and the end of the second sheath layer 30 is covered on the outer periphery of the maze structure 50 and the annular member 42, and the end of the annular member 42 away from the maze structure 50 protrudes from the second sheath layer 30 by a preset distance H1.
[0034] In this embodiment, one end of the annular member 42 away from the labyrinth structure 50 protrudes from the second sheath layer 30 by a preset distance H1. This arrangement facilitates discharge when the composite insulator is applied to a power transmission line.
[0035] In an embodiment of the present invention, the value range of the preset distance H1 is H1>3mm.
[0036] like Figure 1 As shown, in one embodiment of the utility model, the second sheath layer 30 and the umbrella skirt are integrally formed, and the first sheath layer 20 and the umbrella cover are made of the same material.
[0037] In this embodiment, the second sheath layer 30 and the shed are integrally formed, and the second sheath layer 30 and the first sheath layer 20 are made of the same material, so that the cross-linking between the two is the cross-linking between the same substances, and the cross-linking speed is fast and the cross-linking is strong. Through the above arrangement, compared with the prior art of directly injecting the sheath and shed on the core rod surface in sections, on the one hand, the problem of weak interface bonding at the shed connection position can be avoided, and on the other hand, it can effectively ensure that the core rod surface is not corroded by water vapor, and can also solve the problem of low reliability caused by the shed and sheath bonding through room temperature vulcanized silicone rubber in the prior art, so that the composite insulator will not break the core rod in high temperature and high humidity areas, and can effectively ensure the long-term stable operation of the composite insulator.
[0038] like Figure 1 As shown, in one embodiment of the present invention, the thickness of the first sheath layer 20 is H2, the total thickness of the first sheath layer 20 and the second sheath layer 30 is H3, and the value range of H2 / H3 is 1 / 3 to 2 / 5.
[0039] In this embodiment, the thickness of the first sheath layer 20 is relatively thin. If the first sheath layer 20 and the surface of the core rod 10 are not effectively cross-linked and bulging occurs, it is more obvious and easy to observe. The interface bonding effect between the core rod 10 and the first sheath layer 20 can be intuitively judged during the extrusion molding process. At the same time, it can also reduce the manufacturing cost.
[0040] like Figure 1 As shown, in one embodiment of the present invention, the thickness of the first sheath layer 20 ranges from 0.5 mm to 3.0 mm.
[0041] Through the above arrangement, the core rod 10 can be protected from being corroded by water vapor and the manufacturing cost can be reduced.
[0042] Preferably, the thickness of the first sheath layer 20 is 1.5 mm.
[0043] The sheath and shed of existing composite insulators are generally formed in two ways, one is the extrusion shed process and the other is the injection molding process. For products produced by the extrusion shed process, the sheath and shed are bonded by room temperature vulcanized silicone rubber. The electromechanical properties of room temperature vulcanized silicone rubber are far inferior to those of high temperature vulcanized silicone rubber. Under the influence of harsh environments, room temperature vulcanized silicone rubber is prone to aging and failure, resulting in the separation of the shed and the sheath, which cannot effectively guarantee the service life of the shed after shed and the overall protection performance of the core rod. If the sheath and the matching shed are formed by high temperature injection molding after extrusion, the production efficiency is low and industrial mass production cannot be achieved. Therefore, composite insulator products produced by the extrusion shed process are not used in high temperature and high humidity areas. Although the products produced by injection molding are integrally molded, due to the length limitation of the hot plate of the existing injection machine in the industry, composite insulators with a length of more than 2.4m must be injected in sections, resulting in multiple shed locations on a composite insulator. Since the effective cross-linking conditions of the epoxy resin core rod and silicone rubber are relatively harsh, the shed location of the composite insulator injected in sections becomes a weak point of interface bonding, and the shed location is easily punctured during the operation of the product. In addition, the section injection process involves the connection of the shed skirts between sections.
[0044] At present, the connection of shed skirts usually adopts the connection method of connecting shed skirts. The segmented injection products need to be coated with coupling agent, preheated and injected in segments. The shed skirt position is at the end of the injection mold, which makes the process control difficult. In addition, the interface effect of the composite insulator after injection cannot be directly identified and detected by naked eyes or visual recognition technology. Destructive dissection is required to fully determine it. It is impossible to achieve 100% detection in the evaluation of interface bonding effect. The product process quality control is difficult, and there is a problem of poor local bonding leading to reduced product service life. In addition, although the composite insulator products produced by injection molding are integrally formed, due to the length limit of the hot plate of the existing injection machine in the industry, composite insulators with a length of more than 2.4m must be injected in segments, and the segmented injection process involves the connection of shed skirts between segments. At present, the shed skirt connection usually adopts the umbrella connection method. The segmented injection products need to be coated with coupling agent, preheated and injection molded in segments, resulting in multiple umbrella connection parts on a composite insulator. Since the effective cross-linking conditions between the epoxy resin core rod and the silicone rubber are relatively harsh, the umbrella connection part of the segmented injection composite insulator becomes a weak point of interface bonding. During the operation of the product, the umbrella connection part is easily punctured.
[0045] The manufacturing process of the composite insulator of the present application is as follows:
[0046] First, a silane coupling agent is coated on the outer circumference of the entire core rod 10, and then a first sheath layer 20 is extruded on the outer circumference of the core rod 10 by an extruder. The first sheath layer 20 undergoes a cross-linking reaction with the outer circumference of the core rod 10 through the silane coupling agent, so that the first sheath layer 20 is tightly attached to the outer circumference of the core rod 10. The first sheath layer 20 is extruded once and is a whole without any film seams. When performing segmented injection molding of the umbrella cover, there is no need to perform the tedious steps of segmented preheating and segmented application of the silane coupling agent. Segmented injection molding can be directly performed on the outer circumference of the first sheath layer 20, which is more convenient to operate and can improve production efficiency. Since the second sheath layer 30 and the shed are an integrated structure, and the second sheath layer 30 and the first sheath layer 20 are made of the same material, the cross-linking between the two is cross-linking of the same material, so the cross-linking speed is fast and the cross-linking is strong, so that the overall structure of the composite insulator is relatively stable, thereby improving the internal insulation performance of the composite insulator. At the same time, compared with the prior art of directly injecting the sheath and shed in sections on the surface of the core rod 10, the problem of weak interface bonding at the shed connection position can be avoided.
[0047] In addition, after the extrusion of the first sheath layer 20 is completed, the interface bonding effect between the first sheath layer 20 and the core rod 10 can be detected by visual recognition technology. If the interface bonding of the first sheath layer 20 after extrusion molding is poor, the first sheath layer 20 at the corresponding position will bulge 31 on the surface of the core rod 10. The defect detection rate is 100%, which can effectively ensure the effective bonding between the core rod 10 and the first sheath layer 20, replace the traditional injection link dissection (destructive test) process, reduce the waste of raw materials (core rod 10, compound rubber, etc.) in the manufacturing link, reduce the production cost, and create opportunities for winning a broader market.
[0048] It should be noted that when the umbrella cover is segmentedly injection-molded on the outer peripheral surface of the first sheath layer 20 by using an injection molding machine, the injection molding conditions are high temperature and high pressure. During the entire vulcanization and cross-linking stage, there is a pressure of at least 200 bar to squeeze the umbrella cover on the outer peripheral surface of the first sheath layer 20, and the first sheath layer 20 and the second sheath layer 30 are cross-linked with high-temperature vulcanized silicone rubber. The chain initiation between the silicone rubber and the silicone rubber is completed by a peroxide initiator, and then the effective cross-linking between the silicon oxygen chains is completed, that is, the umbrella cover after injection molding is completely bonded to the first sheath layer 20.
[0049] In one embodiment, the raw materials for forming the first sheath layer 20 and the umbrella cover are both high-temperature vulcanized silicone rubber materials. The first sheath layer 20 and the umbrella cover made of silicone rubber materials have the advantages of stable chemical properties, good high temperature resistance, good anti-aging performance, and good insulation performance.
[0050] In one embodiment of the present invention, the step of extruding the first sheath layer 20 on the outer circumference of the entire core rod 10 by using an extruder includes: adding a peroxide initiator to the material forming the first sheath layer 20 .
[0051] In this embodiment, the raw materials for forming the first sheath layer 20 and the second sheath layer 30 are both high-temperature vulcanized silicone rubber materials. The chain initiation between the silicone rubber and the silicone rubber is completed by a peroxide initiator, and then the effective cross-linking between the silicon oxygen chains is completed, which can ensure the interface bonding reliability between the first sheath layer 20 and the second sheath layer 30, reduce the probability of poor interface bonding, and thus provide guarantee for the long-term stable operation of the composite insulator on the transmission line.
[0052] In one embodiment of the present invention, the step of using an injection machine to segmentally inject the umbrella cover on the outer peripheral surface of the first jacket layer 20 includes adding a peroxide initiator to the material forming the second jacket layer 30 .
[0053] In this embodiment, the raw materials for forming the first sheath layer 20 and the second sheath layer 30 are both high-temperature vulcanized silicone rubber materials. The chain initiation between the silicone rubber and the silicone rubber is completed by a peroxide initiator, and then the effective cross-linking between the silicon oxygen chains is completed, which can ensure the interface bonding reliability between the first sheath layer 20 and the second sheath layer 30, reduce the probability of poor interface bonding, and thus provide guarantee for the long-term stable operation of the composite insulator on the transmission line.
[0054] In one embodiment of the utility model, before the step of extruding the first sheath layer 20 on the outer circumference of the entire core rod 10 by using an extruder, the step includes: preheating the core rod 10 coated with a silane coupling agent, and the preheating temperature is 70° C. to 110° C. Before extruding the first sheath layer 20, the core rod 10 is preheated to keep the surface of the core rod 10 dry, and at the same time, it can prevent the first sheath layer 20 from forming pores due to moisture.
[0055] In one embodiment of the utility model, during the process of segmented injection molding of the umbrella cover on the outer peripheral surface of the first sheath layer 20 by using an injection machine, the injection molding is performed by a multi-stage continuous injection method. During the process of segmented injection molding of the umbrella cover on the outer peripheral surface of the first sheath layer 20, the injection molding is performed by a multi-stage continuous injection method, that is, during the segmented injection molding process, there is no need for preheating and brushing of silane coupling agent, and each segment of the injection molding process can be performed continuously. The injection molding process is optimized to "first segment injection, continuous second segment injection until the last segment injection" by the traditional first segment brushing of silane coupling agent, first segment put into an oven for preheating, first segment taken out and put into the injection machine for injection, and the cycle is repeated until the last segment injection is completed, which eliminates the need for the reciprocating turnover and transportation of semi-finished products from the oven to the injection machine, which can reduce manufacturing costs and improve economic benefits.
[0056] In one embodiment of the utility model, before the step of using an injection machine to perform segmented injection molding of the umbrella cover on the outer peripheral surface of the first jacket layer 20, the step includes: detecting the interface between the first jacket layer 20 and the core rod 10 by a visual recognition detection device. The interface between the first jacket layer 20 and the core rod 10 is detected by a visual recognition detection device, and after the detection is qualified, the umbrella cover is multi-stage injection molding is performed, which can ensure the interface bonding reliability of the composite insulator, thereby ensuring the long-term stable operation of the composite insulator on the transmission line.
[0057] In one embodiment of the utility model, the first sheath layer 20 is made of silicone rubber material, and the silicone rubber material is extruded at high temperature on the outer peripheral surface of the entire core rod 10 by an extruder to form the first sheath layer 20. The core rod 10 is made of epoxy resin material, and the coupling agent coated on the outer peripheral surface of the core rod 10 is a silane coupling agent. The extrusion process of the first sheath layer 20 is carried out at high temperature and normal pressure. During the cross-linking process between the core rod 10 and the silicone rubber, the silicone rubber undergoes a cross-linking reaction with the surface of the core rod 10 through the silane coupling agent. The reaction process is that the siloxane chain and the epoxy resin chain are chemically cross-linked, so that the first sheath layer 20 is tightly attached to the surface of the core rod 10. If the silicone rubber and the epoxy resin are not effectively cross-linked, the silicone rubber at the corresponding part is self-contained after high-temperature molding, and obvious bulging will occur. In this way, when the first sheath layer 20 is extruded, the poorly bonded part can be detected by a visual recognition detection device, and the defect rate detection rate is 100%, which solves the industry problem that the interface bonding effect of the composite insulator in the prior art can only be detected by dissection (destructive test).
[0058] As can be seen from the above, the core rod 10 of the present application adopts a dual protection mode, namely a first sheath layer 20 and a second sheath layer 30. The sheath of the first sheath layer 20 is formed by integral high-temperature extrusion, has no mold seam on the surface and has a reliable interface bonding effect, effectively protecting the core rod 10 from being corroded by water vapor. The second sheath layer 30 and the shed are integrally injection molded. When the second sheath layer 30 and the core rod 10 with the first sheath layer 20 are injected, the interface is silicone rubber and silicone rubber. The crosslinking between the two is high-temperature and high-pressure crosslinking of the same material, with a fast crosslinking speed and strong crosslinking. In addition, the second sheath layer 30 and the shed are integrally molded by high temperature and high pressure, which can effectively ensure the long-term stable operation of the composite insulator product.
[0059] In one embodiment of the utility model, in the process of using an extruder to extrude the silicone rubber material at high temperature onto the outer peripheral surface of the entire core rod 10, the temperature of the front drying channel of the extruder is maintained at 450°C to 550°C, and the temperature of the rear drying channel of the extruder is maintained at 250°C to 360°C. The structure of the extruder is an extruder head, a front drying channel and a rear drying channel. The core rod 10 is uniformly extruded from the extruder head by the silicone rubber material. The extruded product is a first sheath layer 20 of fixed size wrapped on the surface of the core rod 10; the extruded product passes through the high temperature section of the front drying channel to quickly complete the surface vulcanization and shaping, so as to prevent the product from softening and deforming after entering the rear drying channel; and then passes through the rear drying channel to complete the effective cross-linking of the core rod 10 and the silicone rubber material.
[0060] In one embodiment, before the step of coating the coupling agent on the outer circumference of the entire core rod, the step includes: grinding and cleaning the core rod and then putting it in a plastic bag for protection to prevent the core rod from being contaminated by dust, debris, etc.
[0061] In the prior art, the specific operation steps of using an injection molding machine to mold a composite insulator sleeve are as follows:
[0062] 1) After the core rod is polished and cleaned, it is covered with a plastic bag for protection;
[0063] 2) End crimping fittings;
[0064] 3) Determine the number of injection sections of the composite insulator based on the product length, the size of the hot plate of the injection machine, etc.;
[0065] 4) Apply silane coupling agent to the injection site;
[0066] 5) The injection site is placed in an oven for preheating at a temperature of 70°C to 110°C;
[0067] 6) Injection molding is performed on the injection site;
[0068] 7) Grind and clean the excess glue at the connecting part to ensure it is clean, and repeat steps 3 to 6 until the entire composite insulator is injection molded. Use existing technology to mold the composite insulator sleeve, and the interface bonding effect between the core rod and the sheath at different sections and the bonding effect at the connecting part must be confirmed by dissection.
[0069] In one embodiment, the manufacturing steps of the composite insulator of the present application are as follows:
[0070] 1) After the core rod is polished and cleaned, it is covered with a plastic bag for protection;
[0071] 2) Apply silane coupling agent to the outer surface of the entire core rod;
[0072] 3) Preheat the entire mandrel to a temperature of 70°C to 110°C;
[0073] 4) using an extruder to extrude a first sheath layer 20 on the outer circumference of the entire mandrel, with a thickness of 0.5 mm to 3.0 mm, and the temperature of the front drying channel of the extruder meets 450° C. to 550° C., and the temperature of the rear drying channel meets 250° C. to 360° C.;
[0074] 5) After the first sheath layer 20 is extruded, the mandrel 10 is rotated 360° and the interface bonding is fully inspected by a visual recognition inspection device;
[0075] 6) After the full inspection is completed, the core rod with the first sheath layer 20 is protected by 10 plastic bags;
[0076] 7) crimping the metal structure 40 at the end of the mandrel 10;
[0077] 8) The umbrella cover is injection molded in sections on the outer peripheral surface of the first sheath layer 20 by using an injection molding machine.
[0078] The composite insulator of the present utility model is described below in conjunction with specific embodiments.
[0079] Embodiment 1:
[0080] The manufacturing steps of composite insulators are as follows:
[0081] 1) The mandrel 10 is 3.5 m long and is in one piece. It is cleaned with anhydrous ethanol and then covered with a plastic bag for protection;
[0082] 2) Applying coupling agent to the outer surface of the entire core rod 10;
[0083] 3) using an extruder to extrude a first sheath layer 20 on the outer circumference of the entire core rod 10, with a thickness of 1.5 mm, the temperature of the front drying channel of the extruder is 520° C., and the temperature of the rear drying channel is 350° C.; 4) using a visual recognition detection device to detect the first sheath layer 20 to confirm whether there is bulging;
[0084] 5) Protect the first sheath layer that has passed the test with 20 sets of plastic bags;
[0085] 6) crimping the metal structure 40 onto the outer periphery of the mandrel 10 by a crimping machine;
[0086] 7) Use a 1100t injection molding machine to mold the umbrella cover in two stages (no need for preheating or coupling agent application);
[0087] 8) After the first stage of injection is completed, the second stage of injection is completed continuously to complete the molding of the entire composite insulator;
[0088] 9) Performance test: The composite insulator of Example 1 was subjected to a dry power frequency test in accordance with GB / T19519-2014 "Definition, test methods and acceptance criteria for suspension and tension composite insulators for overhead line insulators with nominal voltage higher than 1000V AC systems" (this test is a destructive test and the samples after the test can only be scrapped). The test process was divided into 3 sections, each section was 1m long, and 3 points were tested in each section. The test results were 0K, 0.1K, 0K, 0.1K, 0K, 0.2K, 0K, 0K.
[0089] Comparative Example 1:
[0090] The composite insulator of Comparative Example 1 is obtained by the following steps:
[0091] 1) The mandrel is 3.5m long and there are 2 of them. They are cleaned with anhydrous ethanol and protected with a plastic bag.
[0092] 2) Use a 1100t injection molding machine to mold the shed in two stages;
[0093] 3) Apply coupling agent to 1 / 2 length of the mandrel, dry naturally and put it into an oven for preheating;
[0094] 4) When the temperature reaches 70℃~110℃, start injection;
[0095] 5) After one injection is completed, one tube is randomly selected for dissection to confirm the interface bonding condition;
[0096] 6) For the remaining one, grind off the excess glue at the connecting position of the umbrella, and then clean it with anhydrous ethanol;
[0097] 7) Apply coupling agent to the remaining parts, dry naturally and put them in an oven for preheating;
[0098] 8) When the temperature reaches the range of 70℃~110℃, the injection is completed.
[0099] 9) Performance test: The composite insulator of comparative example 1 was subjected to a dry power frequency test in accordance with GB / T19519-2014 "Definition, test methods and acceptance criteria for suspension and tension composite insulators for overhead line insulators with a nominal voltage higher than 1000V for AC systems". The test was divided into 3 sections, each section was 1m long, and 3 points were tested in each section. The test results were 0K, 0.8K, 0.2K, 2.0K, 0.3K, 0.2K, 0.6K, 4.0K, and 0K.
[0100] Embodiment 2:
[0101] The manufacturing steps of the composite insulator of the present application are as follows:
[0102] 1) The mandrel 10 is 6.5 m long and is in one piece. It is cleaned with anhydrous ethanol and then covered with a plastic bag for protection;
[0103] 2) Applying coupling agent to the outer surface of the entire core rod 10;
[0104] 3) The first sheath layer 20 is extruded on the outer circumference of the entire core rod 10 by an extruder, with a thickness of 1.5 mm. The temperature of the front drying channel of the equipment is 520° C., and the temperature of the rear drying channel is 350° C.
[0105] 4) Inspect the first sheath layer 20 by visual recognition detection equipment to confirm whether there is bulging;
[0106] 5) Protect the first sheath layer that has passed the test with 20 sets of plastic bags;
[0107] 6) crimping the metal structure 40 onto the outer periphery of the mandrel 10 by a crimping machine;
[0108] 7) Use a 1100t injection molding machine to mold the umbrella cover in 4 stages (no need for preheating or coupling agent application);
[0109] 8) After the first section is injected, the second, third and fourth sections are injected successively to complete the molding of the entire composite insulator.
[0110] 9) Performance test: The composite insulator of Example 2 was subjected to a dry power frequency test in accordance with GB / T19519-2014 "Definition, test methods and acceptance criteria for suspension and tension composite insulators for overhead line insulators with a nominal voltage higher than 1000V AC systems". The test process was divided into 5 sections, each section was 1m long, and 3 points were tested in each section. The test results were 0K, 0K, 0K, 0.2K, 0.1K, 0K, 0.1K, 0K, 0.3K, 0K, 0K, 0K, 0.2K, 0K.
[0111] Comparative Example 2:
[0112] The composite insulator of Comparative Example 2 is obtained by the following steps:
[0113] 1) The mandrel is 6.5m long and there are 2 of them. They are cleaned with anhydrous ethanol and protected with a plastic bag.
[0114] 2) Use a 1100t injection molding machine to mold the shed in 4 stages;
[0115] 3) Coat the first section of the mandrel to be injected with coupling agent, dry it naturally and put it into an oven for preheating;
[0116] 4) When the temperature reaches 70℃~110℃, start injection;
[0117] 5) After the first injection, one tube was randomly selected for dissection to confirm the interface bonding condition;
[0118] 6) For the remaining one, grind off the excess glue at the connecting position of the umbrella, and then clean it with anhydrous ethanol;
[0119] 7) Complete the second stage of coupling agent coating, dry naturally and then put into an oven for preheating;
[0120] 8) When the temperature reaches the range of 70℃~110℃, the injection is completed;
[0121] 9) Repeat steps 7 and 8 to complete the injection of the third and fourth segments;
[0122] 10) Performance test: The composite insulator of comparative example 2 was subjected to a dry power frequency test in accordance with GB / T19519-2014 "Definition, test methods and acceptance criteria for suspension and tension composite insulators for overhead line insulators with a nominal voltage higher than 1000V for AC systems". The test process was divided into 5 sections, each section was 1m long, and 3 points were tested in each section. The test results were 0.1K, 0.6K, 0.9K, 0K, 4.3K, 0K, 0.9K, 0.5K, 0K, 1.6K, 0.8K, 0K, 0K, 0K, 0.2K.
[0123] Embodiment 3:
[0124] The manufacturing steps of composite insulators are as follows:
[0125] 1) The mandrel 10 is 10.3 m long and is in one piece. It is cleaned with anhydrous ethanol and then covered with a plastic bag for protection;
[0126] 2) Applying coupling agent to the outer surface of the entire core rod 10;
[0127] 3) using an extruder to extrude a first sheath layer 20 on the outer circumference of the entire mandrel 10, with a thickness of 1.5 mm, the temperature of the front drying channel of the extruder being 520° C., and the temperature of the rear drying channel being 350° C.;
[0128] 4) Inspect the first sheath layer 20 by visual recognition detection equipment to confirm whether there is bulging;
[0129] 5) Protect the first sheath layer that has passed the test with 20 sets of plastic bags;
[0130] 6) crimping the metal structure 40 onto the outer periphery of the mandrel 10 by a crimping machine;
[0131] 7) Use a 1100t injection molding machine to mold the umbrella cover in 6 stages (no need for preheating or coupling agent application);
[0132] 8) After the injection of the first section is completed, the injection of the second section, the third section, the fourth section, the fifth section, and the sixth section are completed successively to complete the molding of the entire composite insulator.
[0133] 9) Performance test: The composite insulator of Example 3 was subjected to a dry power frequency test in accordance with GB / T19519-2014 "Definition, test methods and acceptance criteria for suspension and tension composite insulators for overhead line insulators with a nominal voltage higher than 1000V AC systems". The test process was divided into 8 sections, each section was 1m long, and 3 points were tested in each section. The test results were 0.2K, 0K, 0K, 0.3K, 0K, 0.2K, 0K, 0K, 0K, 0K, 0K, 0.1K, 0K, 0K, 0.2K, 0K, 0K, 0.1K, 0K, 0.1K, 0K, 0K, 0.3K.
[0134] Comparative Example 3:
[0135] The composite insulator of Comparative Example 3 is obtained by the following steps:
[0136] 1) The mandrel is 10.3m long and there are 2 of them. They are cleaned with anhydrous ethanol and protected with a plastic bag.
[0137] 2) Use a 1100t injection molding machine to mold the shed in 6 sections;
[0138] 3) Coat the first section of the mandrel to be injected with coupling agent, dry it naturally and put it into an oven for preheating;
[0139] 4) When the temperature reaches 70℃~110℃, start injection;
[0140] 5) After the first injection, one tube was randomly selected for dissection to confirm the interface bonding condition;
[0141] 6) For the remaining one, grind off the excess glue at the connecting position of the umbrella, and then clean it with anhydrous ethanol;
[0142] 7) Complete the second stage of coupling agent coating, dry naturally and then put into an oven for preheating;
[0143] 8) When the temperature reaches the range of 70℃~110℃, the injection is completed;
[0144] 9) Repeat steps 7 and 8 to complete the injection of the third, fourth, fifth, and sixth segments;
[0145] 10) Performance test: The composite insulator of comparative example 3 was subjected to a dry power frequency test in accordance with GB / T19519-2014 "Definition, test methods and acceptance criteria for suspension and tension composite insulators for overhead line insulators with a nominal voltage higher than 1000V for AC systems". The test was divided into 8 sections, each section was 1m long, and 3 points were tested in each section. The test results were 0K, 0.5K, 0K, 0.3K, 1.2K, 0K, 0K, 3.0K, 0K, 0.9K, 0.8K, 0.9K, 0K, 1.0K, 0K, 3.8K, 0.6K, 0K, 0K, 0K, 1.2K, 0K, 2.5K, 0K.
[0146] The composite insulators of the above-mentioned embodiment 1, embodiment 2, embodiment 3, comparative example 1, comparative example 2 and comparative example 3 were subjected to dry power frequency test, and the test results are shown in Table 1:
[0147] Table 1
[0148] Test points Example 1 Comparative Example 1 Example 2 Comparative Example 2 Example 3 Comparative Example 3 1 0 0 0 0.1 0.2 0 2 0.1 0.8 0 0.6 0 0.5 3 0 0.2 0 0.9 0 0 4 0 2 0.2 0 0.3 0.3 5 0.1 0.3 0.1 4.3 0 1.2 6 0 0.2 0 0 0.2 0 7 0.2 0.6 0.1 0.9 0 0 8 0 4 0.1 0.5 0 3 9 0 0 0 0 0 0 10 0.3 1.6 0 0.9 11 0 0.8 0 0.8 12 0 0 0.1 0.9 13 0 0 0 0 14 0.2 0 0 1 15 0 0.2 0.2 0 16 0 3.8 17 0 0.6 18 0.1 0 19 0 0 20 0.1 0 21 0 1.2 22 0 0 23 0 2.5 24 0.3 0 average value 0.04 0.90 0.07 0.66 0.06 0.70 Standard Deviation 0.07 1.32 0.10 1.12 0.10 1.04
[0149] From the above data analysis, it can be seen that: compared with the comparative example, the average temperature rise of the composite insulators of different lengths in the dry power frequency test of the embodiment is 0.04K~0.07K, and the temperature rise values at different points are compared, and the standard deviation is 0.07~0.10, while the average temperature rise of the composite insulators in the dry power frequency test of the comparative example is 0.66K~0.90K, and the standard deviation is 1.04~1.32. From the above, it can be seen that the temperature rise value of the composite insulator dry power frequency test result of the present application is smaller, and the uniformity of the interface bonding of the composite insulator is better.
[0150] From the above description, it can be seen that the above-mentioned embodiments of the utility model achieve the following technical effects: the first sheath layer is coated on the outer periphery of the core rod, which can effectively protect the core rod from being corroded by water vapor, forming a primary water barrier, a maze structure is arranged on the connecting part of the metal component, and a groove is arranged on the outer peripheral wall of the connecting part, and the second sheath layer is coated on the outer periphery of the connecting part, and the protrusion of the second sheath layer is embedded in the groove to form a sealing fit, which can further prevent water vapor from penetrating into the core rod from the end position of the metal structure, forming a secondary water barrier, enhancing the sealing effect on the end of the core rod, thereby improving the moisture resistance of the composite insulator.
[0151] Obviously, the embodiments described above are only some embodiments of the utility model, not all embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.
[0152] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.
[0153] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A composite insulator, characterized in that: include: A mandrel (10); A first sheath layer (20) covering the outer circumference of the core rod (10); An umbrella cover, covering the outer periphery of the first jacket layer (20), the umbrella cover comprising a second jacket layer (30) and an umbrella skirt located on the outer periphery of the second jacket layer (30); as well as A metal structure (40) is sleeved on the end of the core rod (10), the metal structure (40) includes a metal component (41), the metal component (41) includes a connecting portion (53) located at the end of the metal component (41), a labyrinth structure (50) is arranged on the connecting portion (53), a groove (60) is arranged on the outer peripheral wall of the connecting portion (53), the second sheath layer (30) is coated on the outer periphery of the connecting portion (53), a protrusion (31) adapted to the groove (60) is arranged on the second sheath layer (30), and the protrusion (31) and the groove (60) form a sealing fit.
2. The composite insulator according to claim 1, characterized in that: The protrusion (31) and the groove (60) are interference fit.
3. The composite insulator according to claim 1, characterized in that: There are a plurality of the grooves (60) and protrusions (31), the plurality of grooves (60) are arranged at intervals along the length direction of the core rod (10), and the plurality of protrusions (31) are arranged in one-to-one correspondence with the plurality of grooves (60).
4. The composite insulator according to claim 1, characterized in that: The labyrinth structure (50) comprises a convex portion (51) and a concave portion (52), and the second sheath layer (30) is adaptable to both the convex portion (51) and the concave portion (52), and forms a sealing fit with the convex portion (51) and the concave portion (52).
5. The composite insulator according to claim 4, characterized in that: There are a plurality of the convex portions (51) and a plurality of the concave portions (52), and the plurality of the convex portions (51) and the plurality of the concave portions (52) are arranged alternately.
6. The composite insulator according to claim 1, characterized in that: The metal structure (40) further comprises an annular member (42), wherein the annular member (42) is sleeved on the outer circumference of the metal component (41), an end of the second sheath layer (30) is wrapped around the outer circumference of the labyrinth structure (50) and the annular member (42), and an end of the annular member (42) away from the labyrinth structure (50) protrudes from the second sheath layer (30) by a preset distance H1.
7. The composite insulator according to claim 6, characterized in that: The value range of the preset distance H1 is H1>3mm.
8. The composite insulator according to claim 1, characterized in that: The second sheath layer (30) and the umbrella skirt are integrally formed, and the first sheath layer (20) and the umbrella cover are made of the same material.
9. The composite insulator according to claim 1, characterized in that: The thickness of the first sheath layer (20) is H2, the total thickness of the first sheath layer (20) and the second sheath layer (30) is H3, and the value range of H2 / H3 is 1 / 3 to 2 / 5.
10. The composite insulator according to claim 1, characterized in that: The thickness of the first sheath layer (20) ranges from 0.5 mm to 3.0 mm.