Wire hot melting connection method and device

Abstract

The invention discloses a wire hot-melting connection method and device, and relates to the technical field of wire connection, and the method comprises the steps: heating and melting a metal filler in a non-contact manner, pouring the metal filler into a wire gap, and finally cooling to form metallurgical bonding, thereby fundamentally changing the traditional mechanical connection mode, and improving the production efficiency. The defects of high contact resistance and easy heating and oxidation in the traditional crimping method are thoroughly overcome; the formed metallurgical connection body has mechanical strength and conductivity close to those of an original wire, and the long-term operation reliability and stability of a connection point are remarkably improved; according to the device, through cooperation of the heating system and the forming system, an advanced method is materialized into an operable entity, and on-site construction becomes standardized and processized, so that high-quality and high-reliability implementation of the method is guaranteed, dependence on operators is reduced, and uniformity and reliability of construction quality are guaranteed.

Description

Technical Field

[0001] This invention relates to the field of wire splicing technology, and in particular to a method and apparatus for wire thermal fusion splicing. Background Technology

[0002] In power line construction and maintenance, the reliable splicing of metal conductors is directly related to the safe and stable operation of the power grid. For a long time, the industry has mostly used traditional methods such as crimping and mechanical clamp connections for splicing metal conductors in the field. While these methods have been used for many years, their inherent technical models have several unresolved problems: Traditional processes require adapting to wires of different thicknesses, necessitating the preparation of molds, fittings, and specialized tools of various specifications. This not only increases the cost of spare parts management but also slows down the response speed of on-site operations. Moreover, mechanical connections are essentially surface or point contacts, with many microscopic gaps and unevenness between the contact surfaces. The initial contact resistance is already relatively high. During long-term operation, fretting wear and environmental oxidation will continuously damage the contact surfaces, further increasing the contact resistance. This creates a vicious cycle of increased resistance, intensified heating, accelerated oxidation, and further increased resistance, ultimately becoming a hidden danger for overheating faults in the circuit. In addition, the quality of crimping is highly dependent on the skills, experience, and sense of responsibility of the operators. Fluctuations in factors such as pressure, crimping speed, and temperature control can cause hidden problems such as loose connections or overvoltage, making it difficult to guarantee the controllability and consistency of the connection quality and creating uncertain risks for the long-term operation of the line. More importantly, in the context of building a new power system based on new energy sources, the grid connection of new energy sources causes frequent fluctuations in line current. Under such alternating stress, traditional mechanical connection points are more prone to stress relaxation and fatigue loosening, and their dynamic stability can no longer meet the development needs of the future power grid.

[0003] Therefore, there is an urgent need for a new splicing method that can fundamentally change the existing connection methods in order to solve the problems existing in traditional processes. Summary of the Invention

[0004] In view of the problems existing in the above or prior art, the present invention is proposed.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for thermal fusion splicing of wires, comprising the following steps, Prepare the wires to be connected and prepare the metal filler; The ends of the wires are placed into the shaping mold with a gap between them. The metal filler is melted in a heating container by heating to obtain molten metal. The molten metal is poured into the shaping mold to fill the gap between the ends of the wires; After the molten metal cools, a connector is formed that is metallurgically bonded to the end of the wire, thus achieving the connection of the wire.

[0006] As a preferred embodiment of the wire thermal splicing method of the present invention, the method further includes cleaning the end surface of the wire.

[0007] In a preferred embodiment of the wire thermal splicing method of the present invention, the cleaning process includes removing the oxide layer and dirt from the end surface of the wire using mechanical polishing.

[0008] The mechanical grinding cleaning method is simple to operate, low in cost, and easy to implement on site; it can quickly and effectively expose the clean metal surface inside the wire, providing an ideal reaction interface for subsequent metallurgical bonding. In a preferred embodiment of the wire thermal splicing method described in this invention, the heating is performed using non-contact heating.

[0009] By using a non-contact heating method to melt the metal filler, the heating process is energy-concentrated and highly efficient, and the heat source does not come into direct contact with the heated object, thus avoiding problems such as localized overheating and material burn-off that may occur with traditional open flame or contact heating.

[0010] In a preferred embodiment of the wire thermal splicing method of the present invention, the inlet port of the shaping mold is an adjustable port that can adapt to wires of different diameters.

[0011] In a preferred embodiment of the wire thermal splicing method described in this invention, the adjustable port is a quincunx flexible port.

[0012] By adopting a plum blossom-shaped elastic port as the inlet of the forming mold, a single forming mold can adapt to the splicing requirements of various wires with different diameters, reducing the types and quantities of spare parts that need to be carried on site, and lowering inventory management costs and complexity. Furthermore, the coordinated deformation of the elastic petals can adaptively clamp wires of different diameters, providing uniform radial pressure to ensure that the wires are axially aligned and securely fixed during splicing, while protecting the outer layer of the wires from damage and achieving good sealing performance to prevent aluminum liquid leakage.

[0013] In a preferred embodiment of the wire thermal splicing method of the present invention, the cooling is performed by natural cooling, and the cooling time is determined according to the nominal cross-section of the wire and the amount of metal filler.

[0014] In a preferred embodiment of the wire thermal fusion splicing method of the present invention, the amount of metal filler is determined according to the nominal cross-sectional area of ​​the wire and the splicing length.

[0015] The amount of metal filler used is determined by the nominal cross-sectional area of ​​the conductor and the splice length, providing standardized and quantitative management for splicing conductors of different specifications. This greatly reduces reliance on operator experience and ensures the consistency and reliability of splice quality for each connection. It avoids incomplete filling due to insufficient filler and also prevents waste and overflow due to excessive filler.

[0016] The beneficial effects of this plan are: This invention fundamentally revolutionizes traditional mechanical connection methods by non-contact heating and melting of metal filler and pouring it into the gap between wires, followed by cooling to form a metallurgical bond. It completely solves the defects of high contact resistance and easy heat generation and oxidation in traditional crimping methods. The resulting metallurgical connector has mechanical strength and conductivity close to that of the original wires, significantly improving the long-term operational reliability and stability of the connector.

[0017] Another object of the present invention is to provide a wire thermal fusion splicing device, comprising, A heating system for heating metal filler to a molten state, the heating system comprising a high-frequency generator, a coil connected to the high-frequency generator, and a heating container disposed within the coil; A forming system for constraining the ends of the wires to be spliced ​​and containing molten metal, the forming system including a shaping mold.

[0018] As a preferred embodiment of the wire hot-melt splicing device of the present invention, the shaping mold includes a main body, adjustable ports disposed at both ends of the main body for clamping the wire, and a pouring port disposed on one side of the main body for injecting molten metal.

[0019] The main body, adjustable port, and gating gate form a closed and controllable molding environment. The adjustable port is used to securely clamp wires of different diameters, while the gating gate provides a directional and controllable injection channel for the molten metal, ensuring that the molten metal can be accurately poured into and fill the cavity, and fully combine with the end of the wire.

[0020] The beneficial effects of this plan are: This invention materializes an advanced method into an operable entity through the synergy of a heating system and a molding system, making on-site construction standardized and streamlined. This ensures the high-quality and high-reliability implementation of the method, reduces dependence on individual operators, and guarantees the uniformity and reliability of construction quality. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a flowchart illustrating a method for thermally fused splicing of wires.

[0023] Figure 2 This is a schematic diagram of the heating system of a wire thermal fusion splicing device.

[0024] Figure 3 This is a schematic diagram of a heating system (without a heating container) for a wire thermal fusion splicing device.

[0025] Figure 4 This is a schematic diagram of a forming system for a wire hot-melt splicing device.

[0026] Among them, 1. High-frequency generator; 11. Lithium battery; 111. Connecting board; 12. Power module; 13. Water-cooled fan; 2. Coil; 21. Heating container; 31. Main body; 32. Adjustable port; 33. Pour port. Detailed Implementation

[0027] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0028] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0029] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places throughout this specification does not necessarily refer to the same embodiment, nor is it a single embodiment or an embodiment selectively excluded from other embodiments.

[0030] Reference Figures 1-4 This embodiment provides a method for thermally fused splicing of wires, which includes the following steps: Prepare the wires to be connected and prepare the metal filler; in this embodiment, aluminum is used as the metal filler.

[0031] The ends of the wires are placed into the shaping mold with a gap between them; in this embodiment, the gap is 1-2.5mm. The metal filler is melted in a heating container by heating to obtain molten metal liquid. In this embodiment, a graphite crucible is used as the heating container. The molten metal is poured into the shaping mold to fill the gap between the ends of the wires; After the molten metal cools, a connector is formed that is metallurgically bonded to the end of the wire, thus achieving the connection of the wire.

[0032] Reference Figures 1-4 As one embodiment of the present invention, It also includes cleaning the end surfaces of the wire.

[0033] Furthermore, the cleaning process includes using mechanical polishing to remove the oxide layer and dirt from the end surface of the wire.

[0034] In this embodiment, the main focus is on steel-reinforced aluminum stranded wire without cable sheathing, so stripping is not required; the surface is sanded with sandpaper before splicing.

[0035] Reference Figures 1-4 As one embodiment of the present invention, The heating method is non-contact heating.

[0036] In this embodiment, electromagnetic induction heating is employed using a high-frequency generator. The high-frequency generator is the core component of the electromagnetic thermal fusion splicing device for wires. Its working principle is based on electromagnetic induction and resonance technology. Low-voltage DC power is provided by a battery, which is rectified and filtered before being input to a high-frequency inverter module. The inverter module uses an IGBT or MOSFET full-bridge circuit to convert DC power into high-frequency AC power. The output power is precisely controlled by PWM pulse width modulation technology. The high-frequency current is delivered to the high-frequency electromagnetic tube. After the high-frequency AC power is applied to the spiral coil wound inside the electromagnetic tube, a strong alternating magnetic field is generated in the wire splicing area. Eddy currents are formed in the wires in the alternating magnetic field due to electromagnetic induction. The eddy current resistance effect is directly converted into heat, which rapidly heats the aluminum or copper powder in the graphite crucible, causing it to melt. The aluminum material is then poured into a mold that fixes the wires to form a metallurgical bond.

[0037] In this embodiment, the high-frequency generator operates in the range of 20kHz to 200kHz and has an output power range of 2-7kW. The heating temperature can be measured using a handheld infrared thermometer, while the melting state needs to be determined manually. Sodium fluoroaluminate is added to the aluminum material to prevent oxidation. The 2-7kW power of the high-frequency generator heats the graphite crucible. The steady-state equilibrium temperature that the high-frequency generator can reach when operating at its maximum continuous output power of 7kW is limited to below the severe volatilization temperature of aluminum, 1200℃, thus providing a physical basis for preventing vaporization.

[0038] Reference Figures 1-4 As one embodiment of the present invention, The inlet port of the shaping mold is an adjustable port, which can accommodate wires of different diameters; Furthermore, the adjustable port is a quincunx flexible port.

[0039] To enable splicing of wires with various diameters, the forming mold adopts a plum blossom-shaped adjustable tube design. By adjusting the tube diameter, it can adapt to different wire diameters and ensure that the molten metal is evenly distributed at the splice. At the same time, the electromagnetic tube has a built-in water-cooled fan to cope with the heat generated by the high-frequency current and ensure stable operation of the equipment.

[0040] In this embodiment, an LC resonant circuit is introduced. By cooperating with the resonant capacitor and the inductor of the solenoid, the energy transmission efficiency is improved and soft switching operation is achieved, reducing switching losses. The control module uses phase-locked loop (PLL) technology to track load changes in real time and adjust the output frequency to maintain the optimal resonant state, ensuring that the graphite crucible is in the best heating efficiency.

[0041] Reference Figures 1-4 As one embodiment of the present invention, The cooling process employs natural cooling, and the cooling time is determined based on the nominal cross-section of the conductor and the amount of metal filler used; the specific relationship is shown in Table 1: Table 1 Relationship between cooling time and nominal cross-section of the conductor and amount of aluminum used

[0042] The amount of metal filler used is determined based on the nominal cross-sectional area and splice length of the conductor. In this embodiment, aluminum is used as the metal filler, and its amount and heating parameters are based on the cross-sectional area of ​​the conductor and the minimum volume of molten aluminum required to achieve complete coverage and metallurgical bonding.

[0043] The selection of aluminum material usage is based on the fact that the aluminum material usage M is directly proportional to the cross-sectional area S of the conductor and the splice length L. It can be approximately estimated by the formula M=ρ*V=ρ*S*L*k, where ρ is the density of aluminum, V is the volume of the splice area, and k is a process coefficient (usually 1.2~1.5) considering the mold cavity, fillet transition, etc. The empirical data established through experiments are shown in Table 2: Table 2 Aluminum Material Usage and Heating Parameters

[0044] This embodiment is for an aluminum conductor with a nominal cross-section of 70mm², and the conductor specifications are: nominal cross-section of 70mm², diameter of approximately 10.0mm; First, use sandpaper to polish the exposed conductor until it has a metallic luster; Insert the two wires into the plum blossom-shaped adjustable tube opening of the shaping mold, adjust the tube opening to fit tightly with the wires, and keep a gap of 1.0-2.0mm between the ends of the two wires in the center of the tube cavity; Weigh 50g of high-purity aluminum material and place it in a graphite crucible. Add 3g of sodium fluoroaluminate to the aluminum material and stir until well mixed. Place the graphite crucible into the high-frequency electromagnetic tube coil; Start the high-frequency generator, set the output power to 5.2kW and the operating frequency to 90kHz; Monitored by an infrared thermometer, the aluminum material is heated for 3-4 minutes until it reaches and stabilizes at a molten state of 670℃±10℃. Quickly inject the molten aluminum into the shaping tube and allow it to fill naturally. Allow the joint to cool naturally in still air for 6-8 minutes until the temperature is below 60°C, then the mold can be removed.

[0045] After the connection is completed in this way, the DC resistance of the connection point is not higher than the DC resistance of the original conductor of the same length, and the tensile strength of the connection point is not less than 95% of the nominal tensile strength of the original conductor.

[0046] Reference Figures 1-4 The present invention also provides a wire thermal fusion splicing device, comprising, A heating system for heating metal filler to a molten state, the heating system including a high-frequency generator 1, a coil 2 connected to the high-frequency generator 1, and a heating container 21 disposed within the coil 2; The high-frequency generator 1 includes a power module 12, a lithium battery 11, and a water-cooled fan 13. The power module 12 internally supplies 48V to 12V to the circuit. The lithium battery 11 is a standard 6S 10000mAh 25C Grignard battery, consisting of two batteries connected in series. The lithium battery 11 has an external charging interface via a connecting plate 111. The water-cooled fan 13 is a portable 12V-120A radiator with a 36A water pump from Yingbo. The heating container 21 is independent and can be placed inside during use.

[0047] A forming system for constraining the ends of the wires to be spliced ​​and containing molten metal, the forming system including a shaping mold.

[0048] Furthermore, the shaping mold includes a main body 31, adjustable ports 32 disposed at both ends of the main body 31 for clamping wires, and a pouring port 33 disposed on one side of the main body 31 for injecting molten metal. The adjustable ports 32 are quincunx-shaped elastic ports.

[0049] The high-frequency generator 1 has a large power consumption during use, and the equipment is used in an outdoor high-altitude environment. Therefore, it needs to be powered by a lithium battery 11 with a high discharge rate. Since the device generates a lot of heat during operation, ordinary air cooling is insufficient to meet the heat dissipation requirements of the device. Therefore, liquid cooling is required. Furthermore, since the device is used outdoors, the liquid coolant needs to meet the requirements for recycling.

[0050] The spliced ​​wires obtained using this device and method have improved mechanical strength because the aluminum liquid fully fills the gaps between the wires, forming a metallurgical bond; the splice and the wires have more complete contact, with a larger contact area, significantly reducing contact resistance and avoiding the risk of overheating; the plum blossom-shaped shaping mold can adapt to various wire diameters, reducing the types of spare parts; the electromagnetic heating process has a high degree of automation, reducing reliance on operator skills; liquid cooling ensures stable operation of the equipment in outdoor high-altitude environments, with good environmental adaptability.

[0051] Importantly, the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for thermally fused splicing of wires, characterized in that: Includes the following steps, Prepare the wires to be connected and prepare the metal filler; The ends of the wires are placed into the shaping mold with a gap between them. The metal filler is melted in a heating container by heating to obtain molten metal liquid; The molten metal is poured into the shaping mold to fill the gap between the ends of the wires; After the molten metal cools, a connector is formed that is metallurgically bonded to the end of the wire, thus achieving the connection of the wire.

2. The wire thermal fusion splicing method as described in claim 1, characterized in that: It also includes cleaning the end surfaces of the wire.

3. The wire thermal fusion splicing method as described in claim 2, characterized in that: The cleaning process includes using mechanical polishing to remove the oxide layer and dirt from the end surface of the wire.

4. The wire thermal fusion splicing method as described in claim 1, characterized in that: The heating method is non-contact heating.

5. The wire thermal fusion splicing method as described in claim 1, characterized in that: The inlet port of the shaping mold is an adjustable port.

6. The wire thermal fusion splicing method as described in claim 5, characterized in that: The adjustable port is a quincunx flexible port.

7. The wire thermal fusion splicing method as described in claim 1, characterized in that: The cooling is achieved through natural cooling, and the cooling time is determined based on the nominal cross-section of the conductor and the amount of metal filler used.

8. The wire thermal fusion splicing method as described in claim 1, characterized in that: The amount of metal filler used is determined based on the nominal cross-sectional area and splice length of the conductor.

9. A wire thermal fusion splicing device, characterized in that: include, A heating system for heating metal filler to a molten state, the heating system comprising a high-frequency generator (1), a coil (2) connected to the high-frequency generator (1), and a heating container (21) disposed within the coil (2). A forming system for constraining the ends of the wires to be spliced ​​and containing molten metal, the forming system including a shaping mold.

10. The wire thermal fusion splicing device as described in claim 9, characterized in that: The molding die includes a main body (31), adjustable ports (32) at both ends of the main body (31) for clamping wires, and a pouring port (33) on one side of the main body (31) for injecting molten metal.

Images