Wire drawing process for cable copper conductor of liquid cooling over-charging pile

Abstract

The invention discloses a wire drawing process for a cable copper conductor of a liquid cooling over-charging pile, which comprises a copper wire drawing process, and the copper wire drawing process specifically comprises a wire drawing speed control process and a wire drawing oil concentration control process. A proper amount of antioxidant is added, copper sulfate is used for forming a protective oxidation film and preventing copper materials from being oxidized, ethidene diamine is used as a corrosion inhibitor and retarding the corrosion rate of copper, copper phosphate is used as an antirust agent and forming a protective oxidation film, and a preservative and a surfactant are used, so that the corrosion-resistant coating is prepared. A protective film is formed on the surface of the copper wire, air is isolated, and oxidation of the copper wire is reduced; meanwhile, the antioxidant can reduce friction force on the surface of the copper wire, reduce abrasion, improve wire drawing efficiency and product quality, and avoid the problems that in the copper wire drawing production process, friction is generated between the copper wire and parts such as a mold and a guide wheel, the surface temperature of the copper wire is increased, and oxidation is prone to occurring.

Description

Technical Field

[0001] The present invention relates to the technical field of cable copper conductor production, and in particular to a wire drawing process for a liquid-cooled supercharging pile cable copper conductor. Background Art

[0002] Liquid-cooled supercharging technology is an advanced charging technology that uses liquid cooling technology in charging equipment to enable faster and more efficient charging. Liquid-cooled supercharging technology solves the problem that heat dissipation and high-power charging cannot be achieved at the same time, and speeds up charging. During the charging process, high-power currents generate a lot of heat. If the heat is not dissipated in time, it will damage the battery and the charging pile. Conventional charging piles use air-cooled modules for heat dissipation, which can only take away a limited amount of heat. Liquid-cooled supercharging technology adds a liquid cooling channel between the cable and the charging gun. The coolant or oil-cooled insulating oil in it circulates under the impetus of a power pump, taking away more heat, which means that the power of the charging pile can be further improved. In addition, liquid-cooled supercharging technology is also efficient, stable and safe, and is suitable for various types of batteries, including lithium-ion batteries, nickel-metal hydride batteries, etc.

[0003] The liquid-cooled charging pile has a special liquid circulation channel between the cable and the charging gun. Coolant is added to the channel to dissipate heat. The coolant circulation is driven by a power pump to take away the heat generated during the charging process, so as to increase the cable transmission power and achieve high-power charging.

[0004] Compared with the traditional direct ventilation heat dissipation method, liquid cooling can completely isolate the inside and outside of the module, preventing the internal electronic components from direct contact with external dust, salt spray, water vapor, flammable and explosive gases, etc., and can increase the protection level to IP65, which is safer.

[0005] At present, in the copper wire drawing process for the copper conductor of the liquid-cooled super-charging pile cable, the existing technology does not have a particularly good control effect on the drawing speed, the concentration of the drawing oil, the temperature and pH value, the addition of an appropriate dose of antioxidants, and the pay-off and take-up tension parameters during the copper wire twisting production process, which is not conducive to maintaining the stability of the process and affects the consistency of product quality. For this reason, we need to provide a drawing process for the copper conductor of the liquid-cooled super-charging pile cable. It is usually necessary to comprehensively consider multiple factors such as the copper wire material, product specifications, mold conditions, drawing oil performance, and equipment performance to find a suitable production speed balance point to achieve the best combination of production efficiency, product quality, and stable equipment operation. Summary of the invention

[0006] 1. Technical issues to be resolved

[0007] In view of the shortcomings of the prior art, the present invention provides a wire drawing process for the copper conductor of a liquid-cooled supercharging pile cable, which solves the problems raised in the above background.

[0008] (II) Technical solution

[0009] To achieve the above object, the present invention provides the following technical solution: A wire drawing process for a liquid-cooled supercharging pile cable copper conductor, comprising a copper wire drawing process, wherein the copper wire drawing process specifically comprises a wire drawing speed control process, and controls the concentration, temperature and pH value of the wire drawing oil, and specifically comprises the following method steps:

[0010] Step 1: Use a wire drawing unit to draw a single wire from a copper conductor material, use the copper conductor material as a wire to pay off the wire, and draw it into a copper single wire through a wire drawing unit that draws a round core;

[0011] Step 2: Arrange the several copper single wires obtained in step 1 around the round core wire and twist them into a conductor blank by a twisting machine, so that the arc surface of each copper single wire faces the round core wire, and then pre-twist the copper single wire, rotate the copper single wire around its own wire axis, and ensure that the small arc surface of the copper single wire faces the core wire. Finally, each copper single wire and the core wire are combined at a forming and twisting die, and twisted to form a copper conductor blank;

[0012] Step 3: If a double-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 15-19%; the wire drawing oil temperature is 35-45°C; and the wire drawing oil pH value is 8.5-9.5; If a multi-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 4-8%; the wire drawing oil temperature is 35-45°C; and the wire drawing oil pH value is 8.5-9.5;

[0013] Step 4: Place the copper conductor blank in an annealing furnace and heat it to 300-330°C for 6-10 hours, then allow it to cool naturally to room temperature to become a copper conductor semi-finished product;

[0014] Step 5: Wrap the inner insulation layer, protective layer and insulating sheath on the outside of the copper wire semi-finished product. If it passes the electrical test, it is a copper wire conductor.

[0015] Preferably, the diameter of the copper single wire is 0.20-1.8 mm, the speed of the wire drawing unit is controlled at 22-26 m / s, and the wire drawing unit can adopt a double-head wire drawing machine or a multi-head wire drawing machine.

[0016] Preferably, the copper single wire rotates around its own axis at an angle of 180° to 360°, and the pre-twisting direction is opposite to the rotation direction of the stranded wire.

[0017] Preferably, in step 2, the twisted pitch ratio of the outermost layer of twisted wires is 8:20, the twisted pitch ratios of each layer of twisted wires gradually increase from the outside to the inside, and the difference in twisted pitch ratios between two adjacent layers is 3:8.

[0018] Preferably, in the step 2, the copper conductor with a specification of 186 / 0.20AS (1*30+6*26) and a threading method of 2*6&8+2*7 / 1+6 has a pay-off tension of 15N±5N and a take-up tension of 30N±5N for each busbar when bundled; and a pay-off tension of 35N±5N and a take-up tension of 100N±5N for each axis of the busbar when re-twisted.

[0019] Preferably, in the step 4, the conductor blank is placed in a preheated annealing furnace and heated to 310-330° C., maintained for 2-3 hours, then heated to 340-370° C., maintained for 2 hours, and then the conductor blank that has been heated is cooled to a temperature of 250-270° C. at a rate of 12-20° C. per 0.1 hour, and maintained for 2-3 hours. Finally, the conductor blank is taken out of the annealing furnace and allowed to stand and cool naturally to room temperature to obtain a copper conductor semi-finished product.

[0020] Preferably, in step 4, by adding a suitable amount of antioxidant to the original annealing solution ratio, a protective film is formed on the surface of the copper wire to isolate the air and reduce oxidation of the copper wire; at the same time, the antioxidant also reduces the friction on the surface of the copper wire, reduces wear, and improves wire drawing efficiency and product quality.

[0021] Preferably, the antioxidant comprises the following raw materials in the following weight proportions: 1% to 10% sulfate compounds, 0.5% to 5% organic amine compounds, 0.1% to 2% phosphate compounds, and 0.1% to 1% preservative and surfactant mixture.

[0022] Preferably, the sulfate compound is preferably copper sulfate, the organic amine compound is preferably ethylenediamine, and the phosphate compound is preferably copper phosphate.

[0023] Preferably, when a double-head wire drawing machine is used, the daily amount of antioxidant added is 150 ml / day in winter (January-May and October-December) and 300 ml / day in summer (June-September); when a multi-head wire drawing machine is used, the daily amount of antioxidant added is 400 ml.

[0024] (III) Beneficial effects

[0025] Compared with the prior art, the present invention provides a wire drawing process for the copper conductor of a liquid-cooled supercharging pile cable, which has the following beneficial effects:

[0026] 1. The wire drawing process of the copper conductor of the liquid-cooled super charging pile cable is that when a double-head wire drawing machine is used to produce 1.8mm copper wire, the best wire drawing speed is 23-26m / s. When a multi-head wire drawing machine is used to produce 0.20mm copper wire, the best wire drawing speed needs to be controlled at 22-26m / s.

[0027] 2. The wire drawing process of the copper conductor of the liquid-cooled super-charging pile cable effectively controls the wire drawing oil concentration, wire drawing oil temperature and wire drawing oil pH value of the double-head wire drawing machine and the multi-head wire drawing machine to effectively avoid the problem that when the concentration is too high, the viscosity of the wire drawing oil may increase, the resistance in the wire drawing process may increase, the wire drawing energy consumption may increase, the surface quality of the product may be affected, and there may be problems such as unevenness. When the concentration is too low, the lubrication effect is not good, which may easily cause greater friction between the copper wire and the mold and other components, resulting in scratches, heating and even wire breakage on the copper wire surface; the cooling effect is insufficient and the heat generated by friction cannot be effectively taken away. If the temperature is too high, the wire drawing oil will oxidize and volatilize, affecting the wire drawing quality; if the temperature is too low, the viscosity of the wire drawing oil will increase, affecting the wire drawing efficiency. Good control of the pH value is conducive to inhibiting the production of bacteria. If the pH value is too high, the alkalinity of the wire drawing oil will increase, affecting the wire drawing efficiency; if the pH value is too low, the acidity of the wire drawing oil will increase, affecting the wire drawing quality.

[0028] 3. The wire drawing process of the copper conductor of the liquid-cooled super-charging pile cable reasonably adjusts the pay-off and take-up tension according to the material, wire diameter, twisting structure and other factors of the copper wire to avoid different pay-off tensions affecting: A. Twisting uniformity: If the pay-off tension is unstable, the pay-off speeds of each copper wire will be inconsistent, resulting in uneven twisting. B. Conductor deformation: Too much pay-off tension may cause the copper wire to be overstretched and deformed; too little tension may cause the copper wire to be loose and the twisting to be loose. C. Product quality: It will affect the roundness, tightness and other quality indicators of the conductor after twisting. Different take-up tensions will affect: A. Appearance quality: Too much take-up tension will cause the stranded wire to be overstretched, the wire diameter will become smaller, and there will be problems such as strand jumping and burrs; too little take-up tension may cause the stranded wire to be loose and the wire arrangement to be uneven. B. Electrical performance: The take-up tension will affect the electrical properties of the stranded wire, such as resistance and inductance. Too much take-up tension may cause the copper wire to deform, resulting in increased resistance; too little take-up tension may make the structure of the stranded conductor unstable, affecting performance such as inductance.

[0029] 4. The wire drawing process of the copper conductor of the liquid-cooled super charging pile cable increases the appropriate amount of antioxidant, uses copper sulfate, which is usually used to form a protective oxide film to prevent oxidation of copper materials, uses ethylenediamine, which is often used as a corrosion inhibitor to slow down the corrosion rate of copper, and uses copper phosphate, which can be used as a rust inhibitor to form a protective oxide film. Preservatives and surfactants are used to improve the adhesion and corrosion resistance of the coating, and form a protective film on the surface of the copper wire to isolate the air and reduce the oxidation of the copper wire. At the same time, the antioxidant can also reduce the friction on the surface of the copper wire, reduce wear, improve wire drawing efficiency and product quality, and avoid friction between the copper wire and components such as molds and guide wheels during the copper wire drawing production process, which causes the surface temperature of the copper wire to rise and easily cause oxidation. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. 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 these drawings without creative labor. Among them:

[0031] Figure 1 This is a table view of copper wire quality parameters of copper wires of different lengths at the same drawing speed of the present invention.

[0032] Figure 2 This is a copper wire mass fraction parameter diagram of a 1.8 mm long copper wire of the present invention at the concentration, temperature and pH value of the drawing oil.

[0033] Figure 3 This is a copper wire mass fraction parameter diagram of a 0.20 mm long copper wire of the present invention at the concentration, temperature and pH value of the drawing oil. DETAILED DESCRIPTION

[0034] The following will be combined with 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.

[0035] Embodiment 1:

[0036] A wire drawing process for a liquid-cooled supercharging pile cable copper conductor includes a copper wire drawing process, wherein the copper wire drawing process specifically includes a wire drawing speed control process, and controls the concentration, temperature, and pH value of the wire drawing oil, and specifically includes the following method steps:

[0037] Step 1, using a wire drawing unit to draw a single wire from a copper conductor material, using the copper conductor material as a wire pay-off, and drawing it into a copper single wire through a wire drawing unit that draws a round core; the diameter of the copper single wire is 0.20 mm, the speed of the wire drawing unit is controlled at 22 m / s, and the wire drawing unit can use a double-head wire drawing machine or a multi-head wire drawing machine;

[0038] Step 2: Arrange the several copper single wires obtained in step 1 around the round core wire and twist them into a conductor blank through a twisting machine, so that the arc surface of each copper single wire faces the round core wire, and then pre-twist the copper single wire. The copper single wire rotates around its own axis at an angle of 180°. The pre-twisting direction is opposite to the rotation direction of the twisted wire, ensuring that the small arc surface of the copper single wire faces the core wire. Finally, each copper single wire and the core wire are merged at the forming and wiring die, and twisted to form a copper conductor blank; the twisted pitch diameter ratio of the outermost layer of the stranded wire is The ratio of the stranding pitch diameter of each layer of stranded wire is 8:20, and the ratio of the stranding pitch diameter of each layer of stranded wire increases gradually from the outside to the inside, and the difference in the ratio of the stranding pitch diameter between two adjacent layers is 3:8; the copper conductor with the specification of 186 / 0.20AS (1*30+6*26) and the threading method of 2*6&8+2*7 / 1+6, when bundled and twisted, the tension of the pay-off of each busbar is 15N±5N, and the tension of the take-up is 30N±5N; when re-twisting, the tension of the pay-off of each axis of the busbar is 35N±5N, and the tension of the take-up is 100N±5N;

[0039] Step 3: If a double-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 15%, the wire drawing oil temperature is 35°C, and the wire drawing oil pH value is 8.5; if a multi-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 4%, the wire drawing oil temperature is 35°C, and the wire drawing oil pH value is 8.5;

[0040] Step 4: Place the copper wire blank in an annealing furnace and heat it to 300°C for 6 hours, then let it stand and cool naturally to room temperature to become a copper wire semi-finished product; specifically, place the wire blank in a preheated annealing furnace and heat it to 310°C, hold it for 2 hours, then heat it to 340°C, hold it for 2 hours, then cool the wire blank that has been heated to 250°C at a rate of 12°C per 0.1 hour, hold it for 2 hours, and finally take the wire blank out of the annealing furnace and let it stand and cool naturally to room temperature to obtain a copper wire semi-finished product; by adding a suitable amount of antioxidant to the original annealing solution, a protective film can be formed on the surface of the copper wire to isolate air, reducing the oxidation of the copper wire; at the same time, the antioxidant can also reduce the friction of the copper wire surface, reduce wear, and improve the wire drawing efficiency and product quality; the antioxidant includes the following raw materials in weight proportion: 1% sulfate compound, 0.5% organic amine compound, 0.1% phosphate compound, and 0.1% preservative and surfactant mixture; the sulfate compound is preferably copper sulfate, the organic amine compound is preferably ethylenediamine, and the phosphate compound is preferably copper phosphate; if a double-head wire drawing machine is used, the daily antioxidant addition amount is 150ml / day in winter (January-May and October-December) and 300ml / day in summer (June-September); if a multi-head wire drawing machine is used, the daily antioxidant addition amount is 400ml;

[0041] Step 5: Wrap the inner insulation layer, protective layer and insulating sheath on the outside of the copper wire semi-finished product. If it passes the electrical test, it is a copper wire conductor.

[0042] Embodiment 2:

[0043] A wire drawing process for a liquid-cooled supercharging pile cable copper conductor includes a copper wire drawing process, wherein the copper wire drawing process specifically includes a wire drawing speed control process, and controls the concentration, temperature, and pH value of the wire drawing oil, and specifically includes the following method steps:

[0044] Step 1, using a wire drawing unit to draw a single wire from a copper conductor material, using the copper conductor material as a wire pay-off, and drawing it into a copper single wire through a wire drawing unit that draws a round core; the diameter of the copper single wire is 1 mm, the speed of the wire drawing unit is controlled at 23 m / s, and the wire drawing unit can use a double-head wire drawing machine or a multi-head wire drawing machine;

[0045] Step 2: Arrange the several copper single wires obtained in step 1 around the round core wire and twist them into a conductor blank by a twisting machine, so that the arc surface of each copper single wire faces the round core wire, and then pre-twist the copper single wire. The copper single wire rotates around its own axis at an angle of 230°. The pre-twisting direction is opposite to the rotation direction of the twisted wire, ensuring that the small arc surface of the copper single wire faces the core wire. Finally, each copper single wire and the core wire are merged at the forming and wiring die, and twisted to form a copper conductor blank; the twisted pitch ratio of the outermost layer of the stranded wire is The ratio of the stranding pitch diameter of each layer of stranded wire is 8:20, and the ratio of the stranding pitch diameter of each layer of stranded wire increases gradually from the outside to the inside, and the difference in the ratio of the stranding pitch diameter between two adjacent layers is 3:8; the copper conductor with the specification of 186 / 0.20AS (1*30+6*26) and the threading method of 2*6&8+2*7 / 1+6, when bundled and twisted, the tension of the pay-off of each busbar is 15N±5N, and the tension of the take-up is 30N±5N; when re-twisting, the tension of the pay-off of each axis of the busbar is 35N±5N, and the tension of the take-up is 100N±5N;

[0046] Step 3: If a double-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 16%, the wire drawing oil temperature is 40°C, and the wire drawing oil pH value is 9; if a multi-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 5%, the wire drawing oil temperature is 40°C, and the wire drawing oil pH value is 9;

[0047] Step 4: Place the copper conductor blank in an annealing furnace and heat it to 310°C for 7 hours, then let it stand and cool naturally to room temperature to become a semi-finished copper conductor; specifically, place the conductor blank in a preheated annealing furnace and heat it to 315°C, hold it for 2.5 hours, then heat it to 350°C, hold it for 2 hours, then cool the heated conductor blank to 260°C at a rate of 15°C per 0.1 hour, hold it for 2.5 hours, finally take the conductor blank out of the annealing furnace and let it stand and cool naturally to room temperature to obtain a semi-finished copper conductor; by adding an appropriate amount of antioxidant to the original annealing solution, a protective layer can be formed on the surface of the copper wire. The film can isolate the air and reduce the oxidation of the copper wire; at the same time, the antioxidant can also reduce the friction on the surface of the copper wire, reduce wear, and improve the wire drawing efficiency and product quality; the antioxidant comprises the following raw materials in weight proportion: 5% sulfate compound, 1% organic amine compound, 1% phosphate compound, and 0.5% preservative and surfactant mixture; the sulfate compound preferably uses copper sulfate, the organic amine compound preferably uses ethylenediamine, and the phosphate compound preferably uses copper phosphate; if a double-head wire drawing machine is used, the daily antioxidant addition amount is 150ml / day in winter (January-May and October-December) and 300ml / day in summer (June-September); if a multi-head wire drawing machine is used, the daily antioxidant addition amount is 400ml;

[0048] Step 5: Wrap the inner insulation layer, protective layer and insulating sheath on the outside of the copper wire semi-finished product. If it passes the electrical test, it is a copper wire conductor.

[0049] Embodiment three:

[0050] A wire drawing process for a liquid-cooled supercharging pile cable copper conductor includes a copper wire drawing process, wherein the copper wire drawing process specifically includes a wire drawing speed control process, and controls the concentration, temperature, and pH value of the wire drawing oil, and specifically includes the following method steps:

[0051] Step 1, using a wire drawing unit to draw a single wire from a copper conductor material, using the copper conductor material as a wire pay-off, and drawing it into a copper single wire through a wire drawing unit that draws a round core; the diameter of the copper single wire is 1.7 mm, the speed of the wire drawing unit is controlled at 25 m / s, and the wire drawing unit can use a double-head wire drawing machine or a multi-head wire drawing machine;

[0052] Step 2: Arrange the several copper single wires obtained in step 1 around the round core wire and twist them into a conductor blank through a twisting machine, so that the arc surface of each copper single wire faces the round core wire, and then pre-twist the copper single wire. The copper single wire rotates around its own axis at an angle of 300°. The pre-twisting direction is opposite to the rotation direction of the twisted wire, ensuring that the small arc surface of the copper single wire faces the core wire. Finally, each copper single wire and the core wire are combined at the forming and wiring die, and twisted to form a copper conductor blank; the twisted pitch diameter ratio of the outermost layer of the stranded wire is The ratio of the stranding pitch diameter of each layer of stranded wire is 8:20, and the ratio of the stranding pitch diameter of each layer of stranded wire increases gradually from the outside to the inside, and the difference in the ratio of the stranding pitch diameter between two adjacent layers is 3:8; the copper conductor with the specification of 186 / 0.20AS (1*30+6*26) and the threading method of 2*6&8+2*7 / 1+6, when bundled and twisted, the tension of the pay-off of each busbar is 15N±5N, and the tension of the take-up is 30N±5N; when re-twisting, the tension of the pay-off of each axis of the busbar is 35N±5N, and the tension of the take-up is 100N±5N;

[0053] Step 3: If a double-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 18%, the wire drawing oil temperature is 44°C, and the wire drawing oil pH value is 9.3; if a multi-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 7%, the wire drawing oil temperature is 44°C, and the wire drawing oil pH value is 9.3;

[0054] Step 4: Place the copper wire blank in an annealing furnace and heat it to 328°C for 9 hours, then let it stand and cool naturally to room temperature to become a copper wire semi-finished product; specifically, place the wire blank in a preheated annealing furnace and heat it to 328°C, keep it for 2.8 hours, then heat it to 360°C, keep it for 2 hours, then cool the wire blank that has been heated to 360°C at a rate of 18°C ​​per 0.1 hour, keep it for 2.8 hours, finally take out the wire blank from the annealing furnace and let it stand and cool naturally to room temperature to obtain a copper wire semi-finished product; by adding a suitable amount of antioxidant to the original annealing solution ratio, a protective film can be formed on the surface of the copper wire to isolate the air and reduce the oxidation of the copper wire; at the same time, the antioxidant can also The invention can reduce the friction force on the surface of the copper wire, reduce wear, and improve the wire drawing efficiency and product quality; the antioxidant comprises the following raw materials in weight proportion: 9% of sulfate compounds, 4% of organic amine compounds, 1.8% of phosphate compounds, and 0.8% of a mixture of preservatives and surfactants; the sulfate compound preferably uses copper sulfate, the organic amine compound preferably uses ethylenediamine, and the phosphate compound preferably uses copper phosphate; if a double-head wire drawing machine is used, the daily antioxidant addition amount is 150 ml / day in winter (January to May and October to December) and 300 ml / day in summer (June to September); if a multi-head wire drawing machine is used, the daily antioxidant addition amount is 400 ml;

[0055] Step 5: Wrap the inner insulation layer, protective layer and insulating sheath on the outside of the copper wire semi-finished product. If it passes the electrical test, it is a copper wire conductor.

[0056] Embodiment 4:

[0057] A wire drawing process for a liquid-cooled supercharging pile cable copper conductor includes a copper wire drawing process, wherein the copper wire drawing process specifically includes a wire drawing speed control process, and controls the concentration, temperature, and pH value of the wire drawing oil, and specifically includes the following method steps:

[0058] Step 1, using a wire drawing unit to draw a single wire from a copper conductor material, using the copper conductor material as a wire pay-off, and drawing it into a copper single wire through a wire drawing unit that draws a round core; the diameter of the copper single wire is 1.8 mm, the speed of the wire drawing unit is controlled at 26 m / s, and the wire drawing unit can use a double-head wire drawing machine or a multi-head wire drawing machine;

[0059] Step 2: Arrange the several copper single wires obtained in step 1 around the round core wire and twist them into a conductor blank through a twisting machine, so that the arc surface of each copper single wire faces the round core wire, and then pre-twist the copper single wire. The copper single wire rotates around its own axis at an angle of 360°. The pre-twisting direction is opposite to the rotation direction of the twisted wire, ensuring that the small arc surface of the copper single wire faces the core wire. Finally, each copper single wire and the core wire are merged at the forming and wiring die, and twisted to form a copper conductor blank; the twisted pitch diameter ratio of the outermost layer of the stranded wire is The ratio of the stranding pitch diameter of each layer of stranded wire is 8:20, and the ratio of the stranding pitch diameter of each layer of stranded wire increases gradually from the outside to the inside, and the difference in the ratio of the stranding pitch diameter between two adjacent layers is 3:8; the copper conductor with the specification of 186 / 0.20AS (1*30+6*26) and the threading method of 2*6&8+2*7 / 1+6, when bundled and twisted, the tension of the pay-off of each busbar is 15N±5N, and the tension of the take-up is 30N±5N; when re-twisting, the tension of the pay-off of each axis of the busbar is 35N±5N, and the tension of the take-up is 100N±5N;

[0060] Step 3: If a double-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 19%; the wire drawing oil temperature is 45°C; and the wire drawing oil pH value is 9.5; If a multi-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 8%; the wire drawing oil temperature is 45°C; and the wire drawing oil pH value is 9.5;

[0061] Step 4: Place the copper wire blank in an annealing furnace and heat it to 330°C, keep it for 10 hours, and then let it stand and cool naturally to room temperature to become a copper wire semi-finished product; specifically, place the wire blank in a preheated annealing furnace and heat it to 330°C, keep it for 3 hours, then heat it to 370°C, keep it for 2 hours, then cool the wire blank that has been heated to 270°C at a rate of 20°C per 0.1 hour, keep it for 3 hours, and finally take the wire blank out of the annealing furnace and let it stand and cool naturally to room temperature to obtain a copper wire semi-finished product; by adding a suitable amount of antioxidant to the original annealing solution, a protective film can be formed on the surface of the copper wire to isolate the air and reduce The antioxidant can also reduce the friction of the copper wire surface, reduce wear, and improve the wire drawing efficiency and product quality. The antioxidant comprises the following raw materials in weight proportion: 10% sulfate compound, 5% organic amine compound, 2% phosphate compound, and 1% preservative and surfactant mixture. The sulfate compound preferably uses copper sulfate, the organic amine compound preferably uses ethylenediamine, and the phosphate compound preferably uses copper phosphate. If a double-head wire drawing machine is used, the daily antioxidant addition amount is 150 ml / day in winter (January to May and October to December) and 300 ml / day in summer (June to September). If a multi-head wire drawing machine is used, the daily antioxidant addition amount is 400 ml.

[0062] Step 5: Wrap the inner insulation layer, protective layer and insulating sheath on the outside of the copper wire semi-finished product. If it passes the electrical test, it is a copper wire conductor.

[0063] Experimental Example 1:

[0064] Based on the first, second, third and fourth embodiments, the wire drawing speed was adjusted, and the rest was the same. Referring to the method of the above embodiment, the quality of the copper wire obtained in the above experimental example was compared with that of the embodiment. The results are as follows: Figure 1 See Figure 1 It can be found that after adjusting the wire drawing speed, the best wire drawing speed of the double-head large drawing machine when producing 1.8mm copper wire is 23-26m / s, and the best wire drawing speed of the multi-head wire drawing machine when producing 0.20mm copper wire needs to be controlled at 22-26m / s.

[0065] Experimental Example 2:

[0066] On the basis of Examples 1, 2 and 3, the concentration, temperature and pH value of the wire drawing oil were changed, and the rest were the same. Referring to the method of the above embodiment, the quality of the copper wire obtained in the above experimental example was compared with that of the embodiment. The results are as follows: Figure 2 , 3 See Figure 2 , 3It can be found that after changing the concentration, temperature and pH value of the wire drawing oil, if a double-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 19%; the wire drawing oil temperature is 45°C; and the wire drawing oil pH value is 9.5, which is the best; if a multi-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 8%; the wire drawing oil temperature is 45°C; and the wire drawing oil pH value is 9.5, which is the best.

[0067] Judgment criteria: By comparing the copper wire conductors obtained in Examples 1, 2, 3, and 4 with those obtained in Experimental Examples 1 and 2, the wire drawing quality of the copper conductors can be judged.

[0068] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A wire drawing process for a liquid-cooled supercharging pile cable copper conductor, comprising a copper wire drawing process, wherein the copper wire drawing process specifically comprises a wire drawing speed control process, and controls the concentration, temperature and pH value of the wire drawing oil, and is characterized in that: The specific steps include the following: Step 1: Use a wire drawing unit to draw a single wire from a copper conductor material, use the copper conductor material as a wire to pay off the wire, and draw it into a copper single wire through a wire drawing unit that draws a round core; Step 2: Arrange the several copper single wires obtained in step 1 around the round core wire and twist them into a conductor blank by a twisting machine, so that the arc surface of each copper single wire faces the round core wire, and then pre-twist the copper single wire, rotate the copper single wire around its own wire axis, and ensure that the small arc surface of the copper single wire faces the core wire. Finally, each copper single wire and the core wire are combined at a forming and twisting die, and twisted to form a copper conductor blank; Step 3: If a double-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 15-19%; the wire drawing oil temperature is 35-45°C; and the wire drawing oil pH value is 8.5-9.5; If a multi-head wire drawing machine is used for wire drawing, the wire drawing oil concentration is 4-8%; the wire drawing oil temperature is 35-45°C; and the wire drawing oil pH value is 8.5-9.5; Step 4: Place the copper conductor blank in an annealing furnace and heat it to 300-330°C for 6-10 hours, then allow it to cool naturally to room temperature to become a copper conductor semi-finished product; Step 5: Wrap the inner insulation layer, protective layer and insulating sheath on the outside of the copper wire semi-finished product. If it passes the electrical test, it is a copper wire conductor.

2. The wire drawing process of the copper conductor of the liquid-cooled supercharging pile cable according to claim 1 is characterized in that: The diameter of the copper single wire is 0.20-1.8 mm, the speed of the wire drawing unit is controlled at 22-26 m / s, and the wire drawing unit can adopt a double-head wire drawing machine or a multi-head wire drawing machine.

3. The wire drawing process of the copper conductor of the liquid-cooled supercharging pile cable according to claim 1 is characterized in that: The copper single wire rotates around its own wire axis at an angle of 180° to 360°, and the pre-twisting direction is opposite to the rotation direction of the stranded wire.

4. The wire drawing process of the copper conductor of the liquid-cooled supercharging pile cable according to claim 1 is characterized in that: In the step 2, the twisted pitch diameter ratio of the outermost layer of twisted wire is 8:20, the twisted pitch diameter ratio of each layer of twisted wire gradually increases from the outside to the inside, and the difference in twisted pitch diameter ratio between two adjacent layers is 3:

8.

5. The wire drawing process of the copper conductor of the liquid-cooled supercharging pile cable according to claim 1, characterized in that: In the step 2, the copper conductor with a specification of 186 / 0.20AS (1*30+6*26) and a threading method of 2*6&8+2*7 / 1+6 is twisted, and the pay-off tension of each busbar is 15N±5N, and the take-up tension is 30N±5N; when re-twisting, the pay-off tension of each busbar is 35N±5N, and the take-up tension is 100N±5N.

6. The wire drawing process of the copper conductor of the liquid-cooled supercharging pile cable according to claim 1, characterized in that: In the step 4, specifically, the conductor blank is placed in a preheated annealing furnace and heated to 310-330° C., maintained for 2-3 hours, then heated to 340-370° C., maintained for 2 hours, and then the heated conductor blank is cooled to 250-270° C. at a rate of 12-20° C. per 0.1 hour, and maintained for 2-3 hours. Finally, the conductor blank is taken out of the annealing furnace and allowed to stand and naturally cool to room temperature to obtain a copper conductor semi-finished product.

7. The wire drawing process of the copper conductor of the liquid-cooled supercharging pile cable according to claim 1, characterized in that: In the step 4, by adding a suitable amount of antioxidant to the original annealing solution, a protective film is formed on the surface of the copper wire to isolate the air and reduce the oxidation of the copper wire; at the same time, the antioxidant also reduces the friction on the surface of the copper wire, reduces wear, and improves wire drawing efficiency and product quality.

8. The wire drawing process of the copper conductor of the liquid-cooled supercharging pile cable according to claim 7, characterized in that: The antioxidant comprises the following raw materials in proportion by weight: 1% to 10% of sulfate compounds, 0.5% to 5% of organic amine compounds, 0.1% to 2% of phosphate compounds, and 0.1% to 1% of a mixture of preservatives and surfactants.

9. The wire drawing process of the copper conductor of the liquid-cooled supercharging pile cable according to claim 8, characterized in that: The sulfate compound is preferably copper sulfate, the organic amine compound is preferably ethylenediamine, and the phosphate compound is preferably copper phosphate.

10. The wire drawing process of the copper conductor of the liquid-cooled supercharging pile cable according to claim 8, characterized in that: If a double-head wire drawing machine is used, the daily amount of antioxidant added is 150 ml / day in winter (January-May and October-December) and 300 ml / day in summer (June-September); if a multi-head wire drawing machine is used, the daily amount of antioxidant added is 400 ml.

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