Waterproof and explosion-proof high-voltage cable intermediate joint

Abstract

The invention discloses a waterproof explosion-proof high-voltage cable intermediate joint which comprises a conductor connecting pipe, an inner shielding pipe, an insulating prefabricated joint, a reinforcing layer and an outer protective shell which are arranged from inside to outside, the two sides of the conductor connecting pipe are connected with conductors of two sections of cables, the inner shielding pipe is arranged outside the conductor connecting pipe, the insulating prefabricated joint is arranged outside the inner shielding pipe in a sleeving mode, and the reinforcing layer is arranged outside the outer protective shell. Waterproof stress gaskets are arranged between the two ends of the inner shielding pipe and the insulating prefabricated joints; an insulating prefabricated part outer wrapping tape is arranged between the insulating prefabricated connector and the reinforcing layer, the reinforcing layer is sleeved with the outer protective shell, and an anti-corrosion layer is arranged outside the outer protective shell; wherein the reinforcing layer adopts a composite copper shell, copper shells are arranged on the two sides, and a light compressible material is arranged in the center. The waterproof stress gasket and the composite copper shell of the reinforcing layer are matched with each other, so that high-temperature electric arcs can be effectively eliminated, and the possibility of explosion accidents at the position of the middle connector is reduced.

Description

Technical Field

[0001] The invention relates to a waterproof and explosion-proof high-voltage cable intermediate joint, belonging to the technical field of cable preparation. Background Art

[0002] With the acceleration of urbanization and the growing demand for clean energy, the power transmission network is constantly expanding, and the application of high-voltage cables is becoming more and more widespread. In long-distance transmission lines, it is inevitable to use multiple intermediate joints to connect cables in different sections to achieve the continuity and integrity of the entire line. The intermediate connector of the cable is the weak link in the cable line. In engineering practice, about 70% of cable line accidents come from the intermediate joint part, and the factors causing the failure of the intermediate joint are the arc fault at the joint as the main cause. How to solve the arc fault problem of the intermediate joint has become an important problem that needs to be solved in power transmission projects. Summary of the invention

[0003] In order to solve the problems in the above background technology, the present invention provides a waterproof and explosion-proof high-voltage cable intermediate joint.

[0004] The technical solution for achieving the purpose of the present invention is: a waterproof and explosion-proof high-voltage cable intermediate joint, comprising a conductor connecting tube, an inner shielding tube, an insulating prefabricated joint, a reinforcement layer and an outer protective shell arranged from the inside to the outside, wherein the two sides of the conductor connecting tube are connected to the conductors of the two sections of the cable, the inner shielding tube is arranged outside the conductor connecting tube, the insulating prefabricated joint is sleeved on the outside of the inner shielding tube, and waterproof stress gaskets are arranged between the two ends of the inner shielding tube and the insulating prefabricated joint; an insulating prefabricated outer wrapping tape is arranged between the insulating prefabricated joint and the reinforcement layer, the outer protective shell is sleeved on the outside of the reinforcement layer, and an anti-corrosion layer is arranged on the outside of the outer protective shell; wherein the reinforcement layer adopts a composite copper shell.

[0005] In the above structure, the waterproof stress gasket arranged between the two ends of the inner shielding tube and the insulating prefabricated joint can effectively prevent the arc leakage of the inner shielding tube, and the waterproof stress gasket itself has a good equalizing electric field effect, which reduces the possibility of high-temperature arc causing the insulating material to decompose and produce high-pressure decomposition gas and plasma mixture from the source of the arc generation; its reinforcement layer adopts a composite copper shell, and when the waterproof stress gasket has arc overflow, it can eliminate the arc to a certain extent, further reducing the probability of high-temperature arc generation. The cooperation between the two can effectively eliminate the arc, thereby preventing the insulating material from decomposing and producing high-pressure decomposition gas.

[0006] Furthermore, in order to make the reinforcement layer have a buffering function, the reinforcement layer is a three-layer structure, with copper shells on both sides and a lightweight compressible material in the center. At this time, the lightweight compressible material in the middle of the reinforcement layer can play a role in heat dissipation and space buffering when high-pressure cracking gas appears, the possibility of explosion is greatly reduced, and the safety of the middle joint position is greatly improved.

[0007] The conductor connecting tube is made of copper-aluminum alloy, which is smaller in hardness and easier to crimp than pure copper crimping tubes. Copper-aluminum alloy has better conductivity than aluminum alloy crimping tubes on the market, is less likely to cause electrochemical corrosion during long-term contact with the conductor, has a more stable interface, and makes the power transmission process safer.

[0008] In order to achieve the above purpose, the copper-aluminum alloy of the conductor connecting tube is coated with tin or silver on its surface; its composition is 95% copper and 5% aluminum.

[0009] The copper shells on both sides of the composite copper shell structure of the reinforcement layer are copper-based composite materials, and the central lightweight compressible material is conductive foam. The copper-based composite material has good electrical conductivity and thermal conductivity. In addition to being able to conduct charge and quickly eliminate the arc when a high-temperature arc occurs, it has better anti-puncture and wear resistance than pure copper materials.

[0010] Specifically, the doping elements in the copper-based composite materials are molybdenum, chromium and titanium. These components interact with the copper base to form a dense oxide film on the surface of the copper-based composite materials, which is beneficial to improve the ability of the copper-based material to resist arc erosion when encountering an arc.

[0011] The connection of the reinforcement layer is sealed with a sealing ring, and the connection between the reinforcement layer and the metal sheath of the cable is sealed with a lead sleeve; the two sections of the insulating prefabricated joint are coated with sealant, and the connection of the outer protective shell is sealed with a sealing ring and then waterproof glue is injected inside. In this way, when a waterproof stress gasket is included in the intermediate joint structure, at least five layers of sealing structure can be obtained, which prevents moisture in the external environment from directly entering the interior of the joint, thereby reducing the air humidity at the intermediate joint and reducing the probability of high-temperature arc generation.

[0012] The anti-corrosion layer is KNM22 marine anti-corrosion coating, which can not only prevent fouling and corrosion by acid, alkali, chloride ions, etc., but also effectively reduce microbial corrosion. At the same time, the coating has good mechanical strength, does not crack or fall off when immersed in seawater, and has good adhesion to the surface of the underlying material.

[0013] The outer protective shell is made of non-magnetic stainless steel, which has better corrosion resistance in the harsh environment of the ocean, better bonding ability with KNM22 marine anti-corrosion coating than ordinary stainless steel, and better adaptability in highly volatile environments such as ocean currents.

[0014] In order to improve the electric field equalization capability of the waterproof stress gasket and enhance its arc erosion resistance, the waterproof stress gasket is designed to be rectangular, with arc-shaped corners at both ends and a metal woven mesh coated on the outside. In order to further enhance the electric field equalization capability, the short side cross-section can be a spindle cone shape.

[0015] By adopting the above technical solution, the present invention has the following beneficial effects:

[0016] (1) The waterproof stress gaskets provided between the two ends of the inner shielding tube and the insulating prefabricated joints of the present application can effectively prevent arc leakage of the inner shielding tube and the waterproof stress gasket itself has a good electric field homogenization effect, which reduces the possibility of high-temperature arcs causing the insulating material to decompose and produce high-pressure decomposition gas and plasma mixture from the source of the arc generation; its reinforcement layer adopts a composite copper shell, and when the waterproof stress gasket has arc overflow, it can eliminate the arc to a certain extent, further reducing the probability of high-temperature arc generation. The cooperation between the two can effectively eliminate the arc, thereby preventing the insulating material from decomposing and producing high-pressure decomposition gas.

[0017] (2) The reinforcement layer of the present application adopts a three-layer structure. The lightweight compressible material in the middle of the reinforcement layer can play a role in heat dissipation and space buffering when high-pressure cracking gas appears. The possibility of explosion is greatly reduced, and the safety of the middle joint position is greatly improved.

[0018] (3) The conductor connection tube of the present application is made of a copper-aluminum alloy that is easy to crimp and has good electrical conductivity. The possibility of electrochemical corrosion during long-term contact with the conductor is lower, the interface is more stable, and the power transmission process is safer.

[0019] (4) The reinforcing layer copper shell of the present application adopts a copper-based composite material, in which the central lightweight material is a compressible conductive foam, which has better conductivity and thermal conductivity than general structures and materials, and can effectively conduct charge when a high-temperature arc occurs. Compared with the traditional pure copper vacuum structure, it has better anti-puncture and anti-wear capabilities, and can be used in the middle structure of the cable to facilitate explosion-proof.

[0020] (5) The copper-based composite material of the present application is doped with molybdenum, chromium and titanium, and a dense oxide film can be formed on its surface, which has better arc erosion resistance when encountering an arc.

[0021] (6) The structure of the present application has a multi-layer waterproof sealing function, which can effectively prevent water vapor from entering the cable interface, reduce air humidity, and reduce the probability of high-temperature arc generation.

[0022] (7) The anti-corrosion layer of the present application adopts KNM22 marine anti-corrosion coating, which has high mechanical strength, good corrosion resistance in the marine environment, can also reduce microbial corrosion, and has a longer service life in the marine environment.

[0023] (8) The outer protective shell of the present application is made of non-magnetic stainless steel, which has better bonding ability with KNM22 marine anti-corrosion coating than ordinary stainless steel and better adaptability in highly volatile environments such as ocean currents.

[0024] (9) The waterproof stress gasket of the present application is designed to be rectangular, with arc-shaped corners at both ends and a metal woven mesh coated on the outside, and has strong electric field equalization ability and arc erosion resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments and in conjunction with the accompanying drawings, wherein

[0026] Figure 1 It is a schematic diagram of the structure of the present invention.

[0027] Figure 2 This is a simplified diagram of the reinforcing layer structure of the present invention.

[0028] The reference numerals in the accompanying drawings are:

[0029] Conductor connecting tube 1, inner shielding tube 2, insulating prefabricated joint 3, reinforcement layer 4, copper shell 41, buffer layer 42, outer protective shell 5, waterproof stress gasket 6, prefabricated component outer wrapping tape 7, anti-corrosion layer 8. DETAILED DESCRIPTION

[0030] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0031] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0032] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0034] In the description of the embodiments of the present invention, it should be understood that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is conventionally placed when used, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0035] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. The present invention is further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the scope of protection of the present invention.

[0036] (Example 1)

[0037] See Figure 1 and Figure 2 A waterproof and explosion-proof high-voltage cable intermediate joint, comprising a conductor connecting tube 1, an inner shielding tube 2, an insulating prefabricated joint 3, a reinforcement layer 4 and an outer protective shell 5 arranged from the inside to the outside, wherein the conductor connecting tube 1 is connected to the conductors of the two sections of the cable on both sides, the inner shielding tube 2 is arranged outside the conductor connecting tube 1, the insulating prefabricated joint 3 is sleeved on the outside of the inner shielding tube 2, and a waterproof stress gasket 6 is arranged between the two ends of the inner shielding tube 2 and the insulating prefabricated joint 3; an insulating prefabricated outer wrapping tape 7 is arranged between the insulating prefabricated joint 3 and the reinforcement layer 4, the outer protective shell sleeve 5 is arranged outside the reinforcement layer 4, and an anti-corrosion layer 8 is arranged outside the outer protective shell 5; wherein the reinforcement layer 4 adopts a three-layer composite copper shell structure, with copper shells 41 on both sides and a buffer layer 42 in the center, and the buffer layer 42 is made of lightweight compressible material, wherein the conductor connecting tube 1 is made of copper-aluminum alloy.

[0038] During the assembly process, the outer protective layer of the conductor is cut off, and then the insulating prefabricated joint 3 and the copper shell of the cable are respectively inserted into the long end of the cable, and then the surface of the cable conductor is polished, and the debris is cleaned and the conductor is crimped with the conductor connecting tube 1. After crimping, it is inserted into the inner shielding tube 2 and waterproof stress gaskets 6 are added at both ends of the inner shielding tube 2. Then the insulating prefabricated joint 3 is installed. After the installation is completed, sealant is applied to both ends of the insulating prefabricated part 3. After the sealant is dried, the prefabricated part outer tape 7 is covered on its surface, and then the reinforcement layer 4 is installed on the outside. After the installation is completed, the two ends of the reinforcement layer 4 are lead sealed; then the outer protective shell 5 is arranged on the outside, and the two ends are sealed. All joints of the outer protective shell 5 are sealed with sealing rings, and then waterproof glue is injected. After the glue is cured, the glue injection port cover is covered, and finally anti-corrosion paint is sprayed on its surface.

[0039] In order to improve the overall performance of the middle joint, so that the reinforcement layer can have an explosion buffering function on the basis of alleviating the high-voltage arc, and prevent the middle joint from exploding as a whole when the arc fails to be eliminated, the parts in the above structure are further arranged, wherein the copper shells 41 on both sides of the composite copper shell structure of the reinforcement layer 4 are copper-based composite materials, and the central lightweight compressible material 42 is conductive foam.

[0040] In order to prevent excessive corrosion of the intermediate joint or erosion of the internal structure caused by the surface layer falling off due to the marine working environment, the anti-corrosion layer 8 is KNM22 marine anti-corrosion paint; the outer protective shell 5 is made of non-magnetic stainless steel.

[0041] Under the same conditions, in order to make the waterproof stress gasket 6 obtain better electric field equalization ability, the waterproof stress gasket 6 is made of conductive metal composite material, its structure is rectangular, the corners at both ends are arc-shaped, and the outside is covered with a metal woven mesh.

[0042] Taking into account the corrosion resistance of the connecting tube, it is necessary to reduce the potential difference between the connecting tube and the cable conductor while ensuring its conductivity, so its composition is adjusted. Specifically, the conductor connecting tube 1 is made of a copper-aluminum alloy composition, specifically 95% copper and 5% aluminum, and its surface is coated with tin or silver.

[0043] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A waterproof and explosion-proof high-voltage cable intermediate joint, characterized in that: The invention comprises a conductor connection tube (1), an inner shielding tube (2), an insulating prefabricated joint (3), a reinforcement layer (4) and an outer protective shell (5) which are arranged from the inside to the outside. The two sides of the conductor connection tube (1) are connected to the conductors of two sections of the cable. The inner shielding tube (2) is arranged outside the conductor connection tube (1). The insulating prefabricated joint (3) is sleeved outside the inner shielding tube (2). A waterproof stress gasket (6) is arranged between the two ends of the inner shielding tube (2) and the insulating prefabricated joint (3). An insulating prefabricated outer wrapping tape (7) is arranged between the insulating prefabricated joint (3) and the reinforcement layer (4). The outer protective shell (5) is arranged outside the reinforcement layer (4). An anti-corrosion layer (8) is arranged outside the outer protective shell (5). The reinforcement layer (4) adopts a composite copper shell.

2. A waterproof and explosion-proof high-voltage cable intermediate joint according to claim 1, characterized in that: The reinforcement layer (4) adopts a three-layer structure, with copper shells (41) on both sides and a buffer layer (42) in the center, and the buffer layer (42) adopts a light compressible material.

3. The waterproof and explosion-proof high-voltage cable intermediate joint according to claim 1, characterized in that: The conductor connecting tube (1) is made of copper-aluminum alloy.

4. The waterproof and explosion-proof high-voltage cable intermediate joint according to claim 1, characterized in that: The copper shells (41) on both sides of the composite copper shell structure of the reinforcement layer (4) are copper-based composite materials, and the central lightweight compressible material (42) is conductive foam.

5. The waterproof and explosion-proof high-voltage cable intermediate joint according to claim 1, characterized in that: The connection of the reinforcement layer (4) is sealed with a sealing ring, and the connection between the reinforcement layer (4) and the metal sheath of the cable is sealed with a lead sleeve; the two sections of the insulating prefabricated joint (3) are coated with sealing glue, and the connection of the outer protective shell (5) is sealed with a sealing ring and then waterproof glue is injected into the interior.

6. The waterproof and explosion-proof high-voltage cable intermediate joint according to claim 1, characterized in that: The anti-corrosion layer (8) is KNM22 marine anti-corrosion paint.

7. The waterproof and explosion-proof high-voltage cable intermediate joint according to claim 1, characterized in that: The outer protective shell (5) is made of non-magnetic stainless steel.

8. The waterproof and explosion-proof high-voltage cable intermediate joint according to claim 1, characterized in that: The waterproof stress gasket (5) is made of a conductive metal composite material.

9. The waterproof and explosion-proof high-voltage cable intermediate joint according to claim 1, characterized in that: The conductor connecting tube (1) is made of copper-aluminum alloy, and its surface is coated with tin or silver.

10. The waterproof and explosion-proof high-voltage cable intermediate joint according to claim 8, characterized in that: The waterproof stress gasket (5) is rectangular, with arc-shaped corners at both ends and is covered with a metal woven mesh on the outside.

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