Cable intermediate joint and installation method thereof

Abstract

The invention discloses a cable intermediate joint. The cable intermediate joint comprises two butted cables, a cable intermediate joint arranged between the two butted cables and an explosion-proof box, insulating layers at the tail ends of the two butted cables are spiral until cable cores are formed, the cable cores at the tail ends of the two cables are crimped by using a connecting pipe, and a semi-conductive self-adhesive tape is wound outside the connecting pipe; the semi-conductive self-adhesive tape is filled from the lap joint of one cable to the tail end of the other cable until the semi-conductive self-adhesive tape is flush with the cylindrical surfaces of the insulating layers of the two cables; the explosion-proof box is arranged outside the cable intermediate joint, the explosion-proof box is provided with at least two glue pouring ports, and waterproof sealant is poured from one glue pouring port to fill the whole cable gap, so that the waterproof performance of the cable is greatly improved, the installation is simple, and the stability and safety of cable operation are improved.

Description

Technical Field

[0001] The invention relates to the technical field of cable accessory manufacturing, in particular to a cable intermediate joint and an installation method thereof. Background Art

[0002] In power transmission lines, when the cold shrink intermediate joints on the market are constructed, the insulation fracture is perpendicular to the cable core, and the distance from the cable core to the outside of the cable insulation layer is short. Once the cable core is flooded, water or water vapor can easily penetrate into the cold shrink intermediate joint body along the insulation section, causing creepage breakdown inside the intermediate joint body. At the same time, the three-core cold shrink intermediate joints on the market do not have water-blocking structures and waterproof materials in the three phases of the cable. Water will flow from one end of the cable through the intermediate joint to the other end of the intermediate joint, causing water to penetrate the entire cable, increasing the safety risks of the entire cable. The cable intermediate joint is often the most prone to problems among all circuit structures. It is usually made on site or assembled on site. Due to the limitations of on-site conditions, the quality of the joint cannot be well controlled, which in turn affects the safe operation of the busbar. Summary of the invention

[0003] The invention discloses a cable intermediate joint, aiming to provide a safe, reliable and easy-to-construct intermediate joint type to ensure the long-term safe and stable operation of a power transmission system.

[0004] To achieve the above-mentioned purpose, the present invention proposes a cable intermediate joint, characterized in that it includes two butt-jointed cables, a cable intermediate joint and an explosion-proof box arranged in the two butt-jointed cables; the cable insulation layers at the ends of the two butt-jointed cables are spirally shaped until the cable core is formed, the cable cores at the ends of the two cables are crimped with a connecting tube, a semi-conductive self-adhesive tape is wrapped around the outside of the connecting tube, the semi-conductive self-adhesive tape is filled from the overlap of one of the cables to the end of the other cable until it is flush with the cylindrical surface of the cable insulation layers of the two cables; the explosion-proof box is arranged outside the cable intermediate joint, and at least two glue injection ports are opened on the explosion-proof box, and waterproof sealant is injected from one of the glue injection ports to fill the entire cable gap.

[0005] Preferably, a cold shrinkage middle joint body is shrunk outside the semi-conductive self-adhesive tape, and two ends of the cold shrinkage middle joint body extend to cover the two cables respectively.

[0006] Preferably, the cold shrinkable intermediate joint body includes an intermediate joint inner shielding tube, an intermediate joint insulation layer, an intermediate joint outer shielding layer and an intermediate joint stress cone. The intermediate joint inner shielding tube is wrapped around the outer layer of the semi-conductive self-adhesive tape and overlaps with a portion of the cable insulation layer. The intermediate joint outer shielding layer is wrapped around the cable insulation layer and the outside of the intermediate joint inner shielding tube. The intermediate joint stress cone is located between the cable and the intermediate joint outer shielding layer, and wraps around the cable insulation layer and the cable outer semi-conductive layer.

[0007] Preferably, sealing layers are provided at both ends of the cold shrink intermediate joint body, the sealing layers include the sealant and a waterproof tape, and the waterproof tape is wrapped around the sealant.

[0008] Preferably, an insulating tube is shrunk on the waterproof belt, and two ends of the insulating tube are overlapped with the middle joint body and the cable respectively.

[0009] The present invention also provides a method for installing a cable intermediate joint, comprising the following steps:

[0010] S1: Straighten two cables, perform conventional treatment on the cable sheath and shielding layer, make the insulation layer at the ends of the two cables into a spiral shape according to a certain size, obtain a spiral shape, and expose the cable core conductor;

[0011] S2: Crimping the cable cores at the ends of the two cables with a connecting tube;

[0012] S3: A semi-conductive self-adhesive tape is wrapped around the outside of the connecting tube, and the semi-conductive self-adhesive tape fills the overlap from one of the cables to the end of the other cable until it is flush with the cylindrical surfaces of the insulation layers of the two cables;

[0013] S4: Install copper mesh, copper shielded ground wire and armored ground wire outside the middle joint body. After the shielding and grounding are completed, install an explosion-proof box on the outside of the middle joint of the cable. After sealing at both ends of the explosion-proof box, pour waterproof sealant into the glue filling port until the cable gap is filled. After it is full, seal it and wrap flame-retardant tape around the outside of the glue filling port.

[0014] The beneficial effects of the present invention are:

[0015] By setting the insulation layer of the connecting cable into a spiral shape, the distance from the cable core to the outside of the cable insulation layer is greatly extended. At the same time, the outside is wrapped by a semi-conductive self-adhesive tape, and the continuous and stable interface pressure provided by the external cold-shrink intermediate joint body can make the semi-conductive self-adhesive tape filling the step layer tightly and stably arranged on the outside of the step layer insulation. The formed multi-layer sealing ring-like structure can effectively prevent moisture or water from entering the inside of the intermediate joint and prevent the intermediate joint from being punctured, thereby ensuring reliable power transmission and power transmission safety; an explosion-proof box is installed on the outside of the cable intermediate joint, and waterproof sealant is poured. After the waterproof sealant is cured, the gap in the cable is completely filled, which not only enhances the waterproof effect of the outside of the intermediate joint, but also prevents water from flowing from the cable at one end of the intermediate joint to the other end of the cable, avoiding water from penetrating the entire cable as a whole, and completely blocking the flow of water in the cable, which is safer and more reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0017] Figure 1 It is a structural schematic diagram of the cable of the present invention;

[0018] Figure 2 is a cross-sectional view of the cable of the present invention;

[0019] Figure 3 It is a structural schematic diagram of the cold shrinkage intermediate joint body of the present invention;

[0020] Figure 4 The figure is a schematic diagram of the structure of a cable intermediate joint according to an embodiment of the present invention.

[0021] In the above drawings: 11, cable; 111, cable copper shielding layer; 112, cable outer semi-conductive layer; 113, cable insulation layer; 114, cable core; 12, 13, connecting tube; 14, semi-conductive self-adhesive tape; 15, cold shrink intermediate joint body; 151, intermediate joint inner shielding tube; 152, intermediate joint insulation layer; 153, intermediate joint stress cone; 154, intermediate joint outer shielding layer; 16, sealing layer; 161, sealant; 162, waterproof tape; 17, armored ground wire; 18, inner sheath; 19, outer sheath; 20, explosion-proof box; 21, glue filling port.

[0022] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0024] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture (as shown in the accompanying drawings), rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific manner. Therefore, it cannot be understood as a limitation on the present invention. If the specific posture changes, the directional indication will also change accordingly.

[0025] like Figure 1 As shown, the present invention provides a cable intermediate joint, comprising two butt-jointed cables 11, a cable intermediate joint and an explosion-proof box 20 arranged in the two butt-jointed cables; the cable insulation layer 113 at the ends of the two butt-jointed cables 11 is spirally formed until the cable core 114 forms 12, the cable core 114 at the ends of the two cables 11 are crimped with a connecting tube 13, the outer surface of the connecting tube 13 is wrapped with a semi-conductive self-adhesive tape 14, the semi-conductive self-adhesive tape 14 is overlapped from one of the cables 12 and filled to 12 at the end of the other cable until it is flush with the cylindrical surface of the cable insulation layer 113 of the two cables; the explosion-proof box 20 is arranged outside the cable intermediate joint, and at least two glue injection ports 21 are opened on the explosion-proof box 20, and the waterproof sealant 3 is injected from one glue injection port 21 to fill the entire cable gap.

[0026] In this embodiment, if Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, by setting the cable insulation layer 113 of the connecting cable 11 into a spiral shape to obtain 12, the outside is wrapped by a semi-conductive self-adhesive tape 14, and the continuous and stable interface pressure provided by the external cold-shrink intermediate joint body 15 can make the semi-conductive self-adhesive tape 14 filling the step layer tightly and stably arranged on the outside of the spiral insulation layer. The formed multi-layer sealing ring-like structure can effectively prevent moisture or water from entering the inside of the intermediate joint and prevent the intermediate joint from being punctured, thereby ensuring reliable power transmission and power transmission safety. An explosion-proof box 20 is installed on the outside of the cable intermediate joint, and a waterproof sealant 3 is poured. After the waterproof sealant 3 is cured, the gap in the cable is completely filled, thereby completely blocking the flow of water in the cable, thereby enhancing the waterproof effect and being safer and more reliable.

[0027] In actual implementation, the diameters of the two cables 11 and the cable cores 114 are the same.

[0028] In actual implementation, the type of the semi-conductive self-adhesive tape 14 is selected according to the on-site application and is not specifically limited here.

[0029] In actual implementation, the explosion-proof box 20 is made of one of SMC glass fiber reinforced plastic composite materials, stainless steel, aluminum alloy, aluminum-magnesium alloy and cast iron.

[0030] In actual implementation, the cable intermediate joint is preferably used in a three-phase cable.

[0031] In one embodiment, if Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, a cold shrinkage middle joint body 15 is shrunk outside the semi-conductive self-adhesive tape 14, and both ends of the cold shrinkage middle joint body 15 extend to cover the two cables 11 respectively. The cold shrinkage middle joint body 15 can provide a sufficiently stable interface pressure to make the semi-conductive self-adhesive tape 14 tighter and improve the safety of the structure.

[0032] In actual implementation, the size of the cold shrink intermediate joint body 15 is selected according to the specific cable and is not specifically limited here.

[0033] In one embodiment, the cold shrinkable intermediate joint body 15 includes an intermediate joint inner shielding tube 151, an intermediate joint insulation layer 152 and an intermediate joint stress cone 153. The intermediate joint inner shielding tube 151 is wrapped in the outer layer of the semi-conductive self-adhesive tape 14 and overlaps with part of the cable insulation layer 113. The intermediate joint insulation layer 152 is wrapped around the cable insulation layer 113 and the outside of the intermediate joint inner shielding tube 151. The intermediate joint stress cone 153 is located between the cable and the intermediate joint insulation layer 152, and wraps the cable insulation layer 113 and the cable outer semi-conductive layer 112.

[0034] In this embodiment, if Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the intermediate joint inner shielding tube 151, the intermediate joint insulating layer 152 and the intermediate joint stress cone 153 in the cold shrink intermediate joint body 15 are tightly fitted 12 and the semi-conductive self-adhesive tape 14, forming a multi-layer sealing ring-like structure, which is simpler and more effective to prevent water and moisture from entering the interior and prevent the intermediate joint from being punctured, thereby ensuring reliable power transmission and power transmission safety.

[0035] In actual implementation, the material of the middle joint insulating layer 152 is silicone rubber.

[0036] In one embodiment, sealing layers 16 are provided at both ends of the cold shrink intermediate joint body 15 . The sealing layer 16 includes a sealant 161 and a waterproof tape 162 . The waterproof tape 162 is wrapped around the sealant 161 .

[0037] In this embodiment, if Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, sealing layers 16 are provided at both ends of the cold shrink intermediate joint body 15. The waterproof property of the cable mother is improved through the double protection of the sealant 161 and the waterproof tape 162. This structure improves the operating stability and safety of the cable system as a whole.

[0038] In actual implementation, the material of the sealant 161 is not specifically limited, and is preferably polyurethane, epoxy, silicone, etc.

[0039] In one embodiment, an insulating tube is shrunk onto the waterproof tape 162 , and two ends of the insulating tube are overlapped with the middle joint body 15 and the cable 11 respectively.

[0040] In this embodiment, if Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, an insulating tube is shrunk on the waterproof tape 162, which improves the insulation performance of the overall cable structure and ensures the safety of power transmission.

[0041] In actual implementation, the material of the insulating tube is preferably a cold-shrink insulating tube or a heat-shrink insulating tube.

[0042] The present invention also provides a method for installing a cable intermediate joint, comprising the following steps:

[0043] S1: Straighten two cables 11, perform conventional processing on the sheath and shielding layer of the cables 11, make the cable insulation layer 113 at the ends of the two cables 11 into a spiral shape according to a certain size, obtain 12, and expose the cable core 114 conductor;

[0044] S2: crimping the cable cores 114 at the ends of the two cables 11 with the connecting tube 13;

[0045] S3: A semi-conductive self-adhesive tape 14 is wrapped around the connecting tube 13, and the semi-conductive self-adhesive tape 14 is overlapped from one of the cables 12 to the end 12 of the other cable until it is flush with the cylindrical surfaces of the cable insulation layers 113 of the two cables;

[0046] S4: Install the inner sheath 18, the outer sheath 19 and the armored ground wire 17 and other structures outside the intermediate joint body 15. After the shielding and grounding treatment is completed, install the explosion-proof box 20 on the outside of the cable intermediate joint. After the two ends of the explosion-proof box 20 are sealed, the waterproof sealant 3 is poured into the glue filling port 21 until the cable gap is filled. After it is full, it is sealed and the flame retardant tape is wrapped around the outside of the glue filling port 21.

[0047] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A cable intermediate joint for connecting two cables, characterized in that: The invention comprises two butted cables, a cable intermediate joint and an explosion-proof box arranged in the two butted cables; the cable insulation layers at the ends of the two butted cables are spirally shaped until the cable core is formed, the cable cores at the ends of the two cables are crimped by a connecting tube, a semi-conductive self-adhesive tape is wrapped around the outside of the connecting tube, the semi-conductive self-adhesive tape is filled from the overlap of one of the cables to the end of the other cable until it is flush with the cylindrical surfaces of the cable insulation layers of the two cables; the explosion-proof box is arranged outside the cable intermediate joint, and at least two glue injection ports are opened on the explosion-proof box, and waterproof sealant is injected from one of the glue injection ports to fill the entire cable gap.

2. The cable intermediate joint according to claim 1, characterized in that: A cold shrinkage middle joint body is shrunk outside the semi-conductive self-adhesive tape, and two ends of the cold shrinkage middle joint body extend to cover the two cables respectively.

3. The cable intermediate joint according to claim 2, characterized in that: The cold shrinkable intermediate joint body includes an intermediate joint inner shielding tube, an intermediate joint insulation layer, an intermediate joint outer shielding layer and an intermediate joint stress cone. The intermediate joint inner shielding tube is wrapped around the outer layer of the semi-conductive self-adhesive tape and overlaps with a portion of the cable insulation layer. The intermediate joint outer shielding layer is wrapped around the cable insulation layer and the outside of the intermediate joint inner shielding tube. The intermediate joint stress cone is located between the cable and the intermediate joint outer shielding layer, and wraps around the cable insulation layer and the cable outer semi-conductive layer.

4. The cable intermediate joint according to claim 1, characterized in that: Sealing layers are arranged at both ends of the cold shrinkage intermediate joint body. The sealing layers include the sealant and a waterproof tape. The waterproof tape is wrapped around the sealant.

5. The cable intermediate joint according to claim 4, characterized in that: An insulating tube is shrunk on the waterproof belt, and two ends of the insulating tube are overlapped with the middle joint body and the cable respectively.

6. A method for installing a cable intermediate joint, comprising the following steps: S1: Straighten two cables, perform conventional treatment on the cable sheath and shielding layer, make the insulation layer at the ends of the two cables into a spiral shape according to a certain size, obtain a spiral shape, and expose the cable core conductor; S2: Crimping the cable cores at the ends of the two cables with a connecting tube; S3: A semi-conductive self-adhesive tape is wrapped around the outside of the connecting tube, and the semi-conductive self-adhesive tape fills the overlap from one of the cables to the end of the other cable until it is flush with the cylindrical surfaces of the insulation layers of the two cables; S4: Install the copper shielding net, copper shielding ground wire and armored ground wire outside the middle joint body. After the shielding and grounding treatment is completed, install the explosion-proof box on the outside of the middle joint of the cable. After sealing at both ends of the explosion-proof box, pour waterproof sealant into the glue filling port until the cable gap is filled. After it is full, seal it and wrap the flame retardant tape around the outside of the glue filling port.

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