A preparation process for high-strength aluminum alloy conductors for long-span applications

Abstract

The present invention relates to a preparation process of high-strength aluminum alloy conductors for long-span applications, specifically including the following steps: Step 1: Melting of aluminum liquid; Step 2: In-furnace refining; Step 3: Online refining; Step 4: Continuous casting; Step 5: Continuous rolling; Step 6: Drawing and aging; By closing the second control valve and opening the first control valve, the nitrogen gas in the regulation shell rapidly rushes into the airbag, dispersing the small amount of chlorine gas in the airbag, and continuously blowing nitrogen gas mixed with chlorine gas into the airbag, increasing the volume and internal air pressure of the airbag. During this process, the nitrogen gas and chlorine gas entering the airbag are evenly mixed, avoiding reducing the efficiency of breaking the connection between aluminum and all non-wetting impurities; The high-temperature gas is blown onto the filtration box through the output end of the air pump to heat it, achieving the effect of preheating the ceramic filter plate inside, ensuring the normal filtration and slag removal of the melt in the later stage.

Description

Technical Field

[0001] The present invention relates to the technical field of aluminum alloy wire preparation, and specifically to a preparation process for high-strength aluminum alloy wire for long-span applications. Background Art

[0002] Aluminum alloy wires have advantages such as light weight and good electrical conductivity, and are widely used as conductors for overhead transmission lines; conventional aluminum wires have poor heat resistance and cannot meet the needs of large-capacity and long-span applications; research shows that adding trace elements such as Zr, Sc, B, and Y can increase the recrystallization temperature of the alloy, thereby significantly improving heat resistance with little impact on conductivity. Most existing preparation methods for heat-resistant aluminum alloy wires are based on technologies such as conventional casting, continuous casting and rolling, or continuous casting and extrusion to obtain alloy ingot blanks. Such technologies have a low cooling rate and limited solid solubility of alloying elements in the aluminum matrix, restricting the further improvement of the comprehensive performance of heat-resistant aluminum alloys. A solution to the above technical problems needs to be proposed;

[0003] For example, in the patent document with the publication number CN109332706B, this device can significantly increase the solid solubility of alloying elements in the aluminum matrix by adopting atomization powder-making technology, reduce segregation, facilitate the formation of more fine and uniform dispersed phases, and improve the comprehensive performance of heat-resistant aluminum alloys; at the same time, the theoretical length of the produced products can be infinitely long, which is very suitable for the production of large-length products such as wires, and this process flow is short, with less equipment investment, low energy consumption, and high product cost performance;

[0004] However, in the process flow of wire preparation, it is necessary to filter the residual waste slag in the melt through a filter box. If the ceramic filter plate in the filter box is not preheated sufficiently, the molten metal cannot pass through the ceramic filter plate, resulting in production failure; secondly, when stirring the melt, aluminum and all non-wetting impurities are prone to bonding, affecting the product quality. Mixing a small amount of chlorine while introducing nitrogen can solve the above problem. However, in the existing device, the mixing of nitrogen and chlorine is not uniform enough, and it is difficult to control the content of chlorine, reducing the efficiency of breaking the bond between aluminum and all non-wetting impurities. Summary of the Invention

[0005] The technical problems solved by this solution are as follows:

[0006] (1) How to solve the problem that if the ceramic filter plate is not preheated sufficiently, the molten metal cannot pass through the ceramic filter plate, resulting in production failure;

[0007] (2) How to solve the problem that in the existing device, the mixing of nitrogen and chlorine is not uniform enough, and it is difficult to control the content of chlorine, reducing the efficiency of breaking the bond between aluminum and all non-wetting impurities.

[0008] The object of the present invention can be achieved by the following technical solutions: A preparation process for high-strength aluminum alloy conductors for long-span applications, specifically including the following steps:

[0009] Step 1: Add aluminum ingots with a purity greater than 99.70% to the melting furnace and melt them at 670 - 710 °C;

[0010] Step 2: Transfer the molten aluminum in the melting furnace to the holding furnace of the heat preservation device. Sequentially add Al-Fe alloy, Al-Si alloy, Al-Cu alloy, Al-Re alloy, and Al-B alloy within the range of 750 - 760 °C. After fully stirring and mixing evenly, take samples for analysis, stir, perform degassing and slag removal treatment on the melt in the holding furnace, skim off the surface scum, perform static treatment, and then take samples for analysis again; after the slag removal meets the requirements, add Mg ingots and AL-Ti alloy;

[0011] Step 3: Release the melt at a temperature of 760 - 770 °C in the holding furnace. Release the melt from the holding furnace through a launder, and perform on-line degassing and on-line filtration on the melt in the launder; continuously and uninterruptedly feed titanium boron wire at the heating part of the filter box for on-line grain refinement;

[0012] Step 4: Pour the melt refined on-line into a wheel-type crystallizer for continuous casting to form a billet;

[0013] Step 5: When the billet enters the continuous rolling mill, control the temperature of the billet entering the rolling to reach 520 - 530 °C, heat the ingot billet through a frequency multiplier heater, and control the temperature of the ingot billet entering the frequency multiplier heater at 450 - 470 °C; after reaching the temperature of 520 - 530 °C, enter the rolling mill for rolling, and the rolling exit temperature is 300 - 350 °C;

[0014] Step 6: The obtained aluminum rod is drawn through a high-speed aluminum alloy wire drawing machine, and the drawing speed does not exceed 12 m / s, and single wires with a wire diameter of 4.10 mm are obtained through an aging process.

[0015] A further technical improvement of the present invention lies in: In step 2, when adding Mg ingots and AL-Ti alloy, the temperature should not be too high, as too high a temperature will increase the oxidation loss of Mg, and too low an addition temperature will affect the control of the casting temperature; generally control it at about 750 °C, and press the Mg ingots into the bottom of the furnace with a rake for addition; after the Mg ingots melt, add nitrogen for refining and blowing; during degassing, rotate and spray nitrogen into the aluminum and aluminum alloy melt through the L-shaped pipe of the heat preservation device, shear the gas into bubbles to saturate the molten metal, and as the bubbles rise to the surface of the molten aluminum, the dissolved hydrogen is released from the molten metal. Add a small amount of chlorine to nitrogen to break the connection between aluminum and all non-wetting impurities, so that the rising gas bubbles combine with the impurities and float to the surface of the molten aluminum, and the content of chlorine is less than or equal to 0.5%.

[0016] A further technical improvement of the present invention lies in that: in step three, a 40ppi ceramic filter plate is installed inside the filter box.

[0017] A further technical improvement of the present invention lies in that: in step four, at this time, it is crucial to control the casting temperature. Before casting, an automatic temperature control device is adopted to control the casting temperature at 695 - 710 °C; due to the poor fluidity of the melt, the flow rates of the casting cooling water and the emulsion during rolling should be 25% - 30% less than those during the production of 1-series aluminum rods, so as to reduce the cooling rate of the molten aluminum on the crystallization wheel and the cooling rate of the billet during the rolling process.

[0018] A further technical improvement of the present invention lies in that: in step five, the obtained aluminum rod adopts a quenching process. High-pressure quenching water is used to cool and clean the surface of the aluminum rod, so that the temperature of the aluminum rod is reduced to 100 - 130 °C; at the same time, a compressed air device is added at the end of the quenching water, and compressed air is used to blow dry the moisture on the surface of the aluminum rod to avoid the aluminum rod from getting wet and oxidized; finally, the temperature of the aluminum rod is controlled to 50 - 80 °C.

[0019] A further technical improvement of the present invention lies in that: in step five, since the aluminum rod billet is much harder than the billet, therefore, during the rolling process, the pressure and friction generated by the contact between the billet and the rolling rolls are greater. In order to ensure good lubrication of the rolling rolls and the billet by the emulsion, it is necessary to increase the concentration of the emulsion. Due to the differences in equipment, the control during the production process of each manufacturer is also different, and the concentration during the production of this aluminum rod is more than 2.5 times that of the 1-series aluminum rod.

[0020] A further technical improvement of the present invention lies in that: in step six, the aging temperature is 150 °C - 158 °C, the heating-up duration is 50 min - 70 min, and the heat preservation duration is 360 min - 420 min.

[0021] A further technical improvement of the present invention lies in that: in step two, the heat preservation device includes a heat preservation furnace and a blowing mechanism arranged on one side thereof. The L-shaped pipe is fixedly inserted at the bottom of the side of the heat preservation furnace close to the blowing mechanism, and the input end of the L-shaped pipe is fixedly communicated with a metal hose.

[0022] A further technical improvement of the present invention lies in that: in step two, the blowing mechanism includes a regulation shell. A pressure control unit for adjusting the air pressure in the L-shaped pipe is arranged inside the regulation shell. An air inlet pipe for introducing nitrogen is communicated with the side of the regulation shell. A first connecting pipe is communicated with the regulation shell below the air inlet pipe. A first control valve is fixedly installed in the middle of the first connecting pipe, and the output end of the first connecting pipe is fixedly communicated with an airbag. A second connecting pipe is communicated with the bottom of the side of the regulation shell, and the second connecting pipe is communicated with the airbag.

[0023] A further technical improvement of the present invention lies in: in step two, a blowing pipe is connected to the top of the regulating shell, a second control valve is fixedly installed in the middle of the blowing pipe, and the output end of the blowing pipe faces the upper part of the heat preservation furnace.

[0024] A further technical improvement of the present invention lies in: in step two, an adjusting pipe is connected to the end of the first connecting pipe close to the airbag, and a third control valve is fixedly installed in the middle of the adjusting pipe; when degassing the melt is required, the second control valve is closed and the first control valve is opened, so that the nitrogen gas in the regulating shell quickly rushes into the airbag, dispersing a small amount of chlorine gas in the airbag, and continuously blowing nitrogen gas mixed with chlorine gas into the airbag, increasing the volume and the internal air pressure in the airbag. During this process, the nitrogen gas and chlorine gas entering the airbag are evenly mixed, avoiding reducing the efficiency of breaking the bond between aluminum and all non-wetting impurities; when the chlorine content reaches 0.5% of the mixed gas content, at this time, when nitrogen gas is further filled into the airbag, the plug is pushed open, so that the mixed gas is injected into the melt in the heat preservation furnace through the exhaust pipe and the L-shaped pipe, ensuring that the chlorine content in the gas of the mixed gas filled into the melt is less than or equal to 0.5%.

[0025] A further technical improvement of the present invention lies in: in step two, the pressure control unit includes a partition plate fixedly connected to the inner wall of the regulating shell, the partition plate is located below the input end of the first connecting pipe, and a limiting frame is fixedly installed at the bottom of the partition plate. A push rod is movably inserted on the limiting frame. One end of the push rod is fixedly installed with a plug corresponding to the output end of the second connecting pipe. A thrust spring is elastically arranged between the plug and the limiting frame. The bottom of the regulating shell is communicated with the input end of the metal hose through an exhaust pipe.

[0026] A further technical improvement of the present invention lies in: in step two, an air suction pipe is arranged behind the heat preservation furnace, the input end of the air suction pipe faces the upper part of the heat preservation furnace, an air pump is arranged below the heat preservation furnace, the input end of the air pump is communicated with the output end of the air suction pipe, and the position of the output end of the air pump corresponds to the position of the filter box; while blowing air for refining the melt, by turning on the air pump, the air pump cooperates with the air suction pipe to draw away the high-temperature air above the melt, and at the same time cooperates with the output end of the air pump to blow the high-temperature gas to the filter box to heat it, achieving the effect of preheating the ceramic filter plate inside it and ensuring the normal filtration and slag removal of the melt in the later stage.

[0027] A further technical improvement of the present invention lies in: in step two, a flow channel is fixedly arranged at the top of the side of the heat preservation furnace away from the L-shaped pipe.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] When the present invention is in use, when degassing the melt is required, the second control valve is closed and the first control valve is opened, so that nitrogen in the regulation shell quickly rushes into the airbag, dispersing a small amount of chlorine gas in the airbag, and continuously blowing nitrogen mixed with chlorine gas into the airbag, increasing the volume and internal air pressure in the airbag. During this process, the nitrogen and chlorine gas entering the airbag are evenly mixed, avoiding reducing the efficiency of breaking the bond between aluminum and all non-wetting impurities; when the chlorine content reaches 0.5% of the mixed gas content, at this time, when nitrogen is filled into the airbag again, the plug is pushed open, so that the mixed gas is injected into the melt in the holding furnace through the exhaust pipe and the L-shaped pipe, ensuring that the chlorine content in the gas of the mixed gas filled into the melt is less than or equal to 0.5%.

[0030] When the present invention is in use, while blowing air for refining the melt, by turning on the air pump, the air pump cooperates with the suction pipe to draw away the high-temperature air above the melt, and at the same time, the high-temperature gas is blown against the filter box through the output end of the air pump to heat it, achieving the effect of preheating the ceramic filter plate inside it, ensuring the normal filtration and slag removal of the melt in the later stage. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] For the convenience of those skilled in the art to understand, the present invention will be further described below with reference to the accompanying drawings.

[0032] Figure 1 Schematic diagram of the wire preparation process flow of the present invention;

[0033] Figure 2 Schematic diagram of the structure of the heat preservation device of the present invention;

[0034] Figure 3 Schematic diagram of the structure of the air blowing mechanism of the present invention;

[0035] Figure 4 For the present invention Figure 3 Enlarged view of the structure at A in the present invention.

[0036] In the figure: 1. Air blowing mechanism; 2. Metal hose; 3. L-shaped pipe; 4. Air pump; 5. Holding furnace; 6. Suction pipe; 101. Regulation shell; 102. First control valve; 103. Inlet pipe; 104. Adjusting pipe; 105. First connecting pipe; 106. Airbag; 107. Second connecting pipe; 108. Pressure control unit; 109. Blowing pipe; 110. Second control valve; 1081. Partition board; 1082. Limit frame; 1083. Plug; 1084. Exhaust pipe; 1085. Push rod. DETAILED DESCRIPTION OF THE INVENTION

[0037] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts belong to the scope of protection of the present invention.

[0038] Please refer to Figures 1-4 as shown, a preparation process of high-strength aluminum alloy wire for long-span use specifically includes the following steps:

[0039] Step 1: Add aluminum ingots with a purity greater than 99.70% into the melting furnace and melt at 670 - 710 °C;

[0040] Step 2: Transfer the aluminum liquid in the melting furnace to the holding furnace 5 of the heat preservation device, and sequentially add Al-Fe alloy, Al-Si alloy, Al-Cu alloy, Al-Re alloy, and Al-B alloy within the range of 750 - 760 °C. After fully stirring evenly, take samples for analysis, stir, perform degassing and slag removal treatment on the melt in the holding furnace 5, skim off the surface scum, perform static treatment, and then take samples for analysis; after the slag removal meets the requirements, add Mg ingots and AL-Ti alloy;

[0041] Step 3: Discharge at a temperature of 760 - 770 °C in the holding furnace 5. Discharge the melt from the holding furnace 5 through the launder, and perform on-line degassing and on-line filtration on the melt in the launder; continuously and uninterruptedly feed titanium-boron wire at the heating part of the filtration box to refine the grains on-line;

[0042] Step 4: Pour the melt refined on-line into a wheel-type crystallizer for continuous casting to form a billet;

[0043] Step 5: When the billet enters the continuous rolling mill, control the temperature of entering the rolling to reach 520 - 530 °C, heat the ingot billet through a frequency multiplier heater, and control the temperature of the ingot billet entering the frequency multiplier heater to be 450 - 470 °C; after reaching the temperature of 520 - 530 °C, enter the rolling mill for rolling, and the rolling exit temperature is 300 - 350 °C;

[0044] Step 6: The obtained aluminum rod is drawn through a high-speed aluminum alloy wire drawing machine, and the drawing speed does not exceed 12 m / s, and single wires with a wire diameter of 4.10 mm are obtained through the aging process.

[0045] Please refer to Figures 1-3As shown in the figure, in the above step 2, when adding Mg ingots and Al-Ti alloy, the temperature should not be too high. If the temperature is too high, the oxidation and burning loss of Mg will increase. If the addition temperature is too low, it will affect the control of the casting temperature. Generally, it is controlled at about 750°C. Use a rake to press the Mg ingots into the bottom of the furnace for addition. After the Mg ingots are melted, add nitrogen for refining and blowing. During degassing, nitrogen is sprayed into the aluminum and aluminum alloy melt in a rotating manner through the L-shaped pipe 3 of the heat preservation device, and the gas is sheared into bubbles to saturate the molten metal. As the bubbles rise to the surface of the molten aluminum, the dissolved hydrogen is released from the molten metal. Add a small amount of chlorine to the nitrogen to break the connection between aluminum and all non-wetting impurities, so that the rising gas bubbles combine with the impurities and float to the surface of the molten aluminum. The content of chlorine is less than or equal to 0.5%.

[0046] Please refer to Figure 1 As shown in the figure, in the above step 3, a 40ppi ceramic filter plate is installed inside the filter box.

[0047] Please refer to Figures 1-3 As shown in the figure, in the above step 4, at this time, the key is to control the casting temperature. Before casting, use an automatic temperature control device to control the casting temperature at 695 - 710°C. Since the fluidity of the melt is poor, the flow rate of the casting cooling water and the emulsion during rolling should be 25% - 30% less than that when producing 1-series aluminum rods, so as to reduce the cooling rate of the aluminum water on the crystallizing wheel and the cooling rate of the billet during the rolling process.

[0048] Please refer to Figure 1 As shown in the figure, in the above step 5, the obtained aluminum rod adopts a quenching process. Use quenching water with a relatively high pressure to cool and clean the surface of the aluminum rod, so that the temperature of the aluminum rod drops to 100 - 130°C. At the same time, add a compressed air device at the end of the quenching water to blow dry the moisture on the surface of the aluminum rod with compressed air to avoid damp oxidation of the aluminum rod. Finally, the temperature of the aluminum rod is controlled at 50 - 80°C.

[0049] Please refer to Figure 1 As shown in the figure, in the above step 5, since the aluminum rod billet is much harder than the billet, therefore, during the rolling process, the pressure and friction generated by the contact between the billet and the rolling rolls are greater. In order to ensure good lubrication of the rolling rolls and the billet by the emulsion, it is necessary to increase the concentration of the emulsion. Due to the differences in equipment, the control during the production process of each manufacturer is also different. The concentration when producing this aluminum rod is more than 2.5 times that of producing 1-series aluminum rods.

[0050] Please refer to Figure 1 As shown in the figure, in the above step 6, the aging temperature is 150°C - 158°C, the heating-up time is 50min - 70min, and the heat preservation time is 360min - 420min.

[0051] Please refer to Figures 2-4As shown, in the above step two, the heat preservation device includes a heat preservation furnace 5 and a blowing mechanism 1 arranged on one side thereof. An L-shaped pipe 3 is fixedly inserted at the bottom of the side of the heat preservation furnace 5 close to the blowing mechanism 1, and a metal hose 2 is fixedly connected to the input end of the L-shaped pipe 3.

[0052] Please refer to Figure 2 and Figure 3 As shown, in the above step two, the blowing mechanism 1 includes a regulating shell 101. A pressure control unit 108 for regulating the air pressure in the L-shaped pipe 3 is arranged inside the regulating shell 101. An air inlet pipe 103 for introducing nitrogen is connected to the side of the regulating shell 101. A first connecting pipe 105 is connected to the regulating shell 101 below the air inlet pipe 103. A first control valve 102 is fixedly installed in the middle of the first connecting pipe 105, and the output end of the first connecting pipe 105 is fixedly connected to an airbag 106. A second connecting pipe 107 is connected to the bottom of the side of the regulating shell 101, and the second connecting pipe 107 is connected to the airbag 106.

[0053] Please refer to Figure 2 and Figure 3 As shown, in the above step two, a blowing pipe 109 is connected to the top of the regulating shell 101. A second control valve 110 is fixedly installed in the middle of the blowing pipe 109, and the output end of the blowing pipe 109 faces above the heat preservation furnace 5.

[0054] Please refer to Figure 3 As shown, in the above step two, an adjusting pipe 104 is connected to the end of the first connecting pipe 105 close to the airbag 106. A third control valve is fixedly installed in the middle of the adjusting pipe 104; when degassing the melt is required, the second control valve 110 is closed and the first control valve 102 is opened, so that the nitrogen in the regulating shell 101 quickly rushes into the airbag 106, dispersing a small amount of chlorine gas in the airbag 106. Nitrogen mixed with chlorine gas is continuously blown into the airbag 106, increasing the volume and the internal air pressure of the airbag 106. During this process, the nitrogen and chlorine gas entering the airbag 106 are evenly mixed, avoiding reducing the efficiency of breaking the connection between aluminum and all non-wetting impurities; when the chlorine content reaches 0.5% of the mixed gas content, at this time, when nitrogen is filled into the airbag 106 again, the plug 1083 is pushed open, so that the mixed gas is injected into the melt in the heat preservation furnace 5 through the exhaust pipe 1084 and the L-shaped pipe 3, ensuring that the chlorine content in the gas of the mixed gas filled into the melt is less than or equal to 0.5%.

[0055] Please refer to Figure 3 and Figure 4As shown in the figure, in the above step two, the pressure control unit 108 includes a partition plate 1081 fixedly connected to the inner wall of the regulation housing 101. The partition plate 1081 is located below the input end of the first connecting pipe 105, and a limiting frame 1082 is fixedly installed at the bottom of the partition plate 1081. A push rod 1085 is movably inserted on the limiting frame 1082. One end of the push rod 1085 is fixedly installed with a plug 1083 corresponding to the output end of the second connecting pipe 107. A thrust spring is elastically arranged between the plug 1083 and the limiting frame 1082. The bottom of the regulation housing 101 is communicated with the input end of the metal hose 2 through an exhaust pipe 1084.

[0056] Please refer to Figure 2 As shown in the figure, in the above step two, an air suction pipe 6 is arranged behind the heat preservation furnace 5. The input end of the air suction pipe 6 faces the upper part of the heat preservation furnace 5. An air pump 4 is arranged below the heat preservation furnace 5. The input end of the air pump 4 is communicated with the output end of the air suction pipe 6, and the position of the output end of the air pump 4 corresponds to the position of the filter box; while blowing air for refining the melt, by turning on the air pump 4, the air pump 4 cooperates with the air suction pipe 6 to suck away the high-temperature air above the melt, and at the same time, cooperates with the output end of the air pump 4 to blow the high-temperature gas to the filter box to heat it, so as to preheat the ceramic filter plate inside it, ensuring the normal filtering and slag removal of the melt in the later stage.

[0057] Please refer to Figure 2 As shown in the figure, in the above step two, a flow channel is fixedly arranged at the top of the side of the heat preservation furnace 5 far away from the L-shaped pipe 3.

[0058] Working principle: When the present invention is in use, first, before the magnesium ingots in the melt in the heat preservation furnace 5 melt, close the first control valve 102 and open the third control valve. First, dry the air in the airbag 106 through the regulating pipe 104, and then inject a small amount of chlorine gas into it, and promptly close the third control valve; when the magnesium ingots melt, turn on the external blowing device and the second control valve 110, and inject nitrogen gas into the regulating shell 101 through the air inlet pipe 103. At this time, the nitrogen gas will be blown out from the output end of the blowing pipe 109 towards the upper part of the heat preservation furnace 5 to refine and blow the melt; when degassing the melt is required, close the second control valve 110 and open the first control valve 102, so that the nitrogen gas in the regulating shell 101 quickly rushes into the airbag 106, dispersing the small amount of chlorine gas in the airbag 106, and continue to blow nitrogen gas mixed with chlorine gas into the airbag 106, increasing the volume and the internal air pressure in the airbag 106. During this process, the nitrogen gas and chlorine gas entering the airbag 106 are evenly mixed to avoid reducing the efficiency of breaking the connection between aluminum and all non-wetting impurities; when the chlorine content reaches 0.5% of the mixed gas content, at this time, fill the airbag 106 with nitrogen gas again, then push open the plug 1083, so that the mixed gas enters the melt in the heat preservation furnace 5 through the exhaust pipe 1084 and the L-shaped pipe 3, ensuring that the chlorine content in the gas of the mixed gas filled into the melt is less than or equal to 0.5%; while refining and blowing the melt, turn on the air pump 4, so that the air pump 4 cooperates with the suction pipe 6 to suck away the high-temperature air above the melt, and at the same time cooperate with the output end of the air pump 4 to blow the high-temperature gas to the filter box to heat it, achieving the effect of preheating the ceramic filter plate inside it and ensuring the normal filtering and slag removal of the melt in the later stage.

[0059] To further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following will, in combination with the accompanying drawings and preferred embodiments, describe in detail the specific implementation manners, structures, features and their effects of the present invention as follows.

[0060] The above is only a preferred embodiment of the present invention, and does not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the above-disclosed technical content to be equivalent change equivalent embodiments within the scope of the technical solution of the present invention. However, any brief modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A preparation process for high-strength aluminum alloy conductors for long-span applications, characterized in that: Specifically, it includes the following steps: Step 1: Add aluminum ingots with a purity greater than 99.70% into the melting furnace and melt them at 670 - 710 °C; Step 2: Transfer the molten aluminum in the melting furnace to the holding furnace of the heat preservation device, and successively add Al-Fe alloy, Al-Si alloy, Al-Cu alloy, Al-Re alloy, and Al-B alloy within the range of 750 - 760 °C. After fully stirring and mixing evenly, take samples for analysis, stir, perform degassing and slag removal treatment on the melt in the holding furnace, skim off the surface floating slag, perform static treatment, and then take samples for analysis again; after the slag removal meets the requirements, add Mg ingots and AL-Ti alloy; Step 3: Discharge at a temperature of 760 - 770 °C in the holding furnace. Discharge the melt from the holding furnace through a launder, and perform on-line degassing and on-line filtration on the melt in the launder; continuously and uninterruptedly feed titanium boride wire at the heating part of the filter box for on-line grain refinement; Step 4: Pour the melt refined on-line into a wheel-shaped mold for continuous casting to form a billet; Step 5: When the billet enters the continuous rolling mill, control the temperature of the billet entering the rolling to reach 520 - 530 °C, heat the billet through a frequency multiplier heater, and control the temperature of the billet entering the frequency multiplier heater to be 450 - 470 °C; after reaching the temperature of 520 - 530 °C, enter the rolling mill for rolling, and the rolling exit temperature is 300 - 350 °C; Step 6: The obtained aluminum rod is drawn through a high-speed aluminum alloy wire drawing machine, and the drawing speed does not exceed 12 m / s, and single wires with a wire diameter of 4.10 mm are obtained through the aging process; In Step 2, when adding Mg ingots and AL-Ti alloy, control the temperature at 750 °C, use a rake to press the Mg ingots into the bottom of the furnace for addition; after the Mg ingots melt, add nitrogen for refining blowing; during degassing, rotate and spray nitrogen into the aluminum and aluminum alloy melt through the L-shaped pipe of the heat preservation device to shear the gas into bubbles to saturate the molten metal. As the bubbles rise to the surface of the molten aluminum, the dissolved hydrogen is released from the molten metal. Add a small amount of chlorine to the nitrogen to break the connection between aluminum and all non-wetting impurities, so that the rising gas bubbles combine with the impurities and float to the surface of the molten aluminum, and the content of chlorine is not higher than 0.5%.

2. A preparation process for high-strength aluminum alloy conductors for long-span applications according to claim 1, characterized in that, in Step 3, a 40ppi ceramic filter plate is installed inside the filter box.

3. A preparation process for high-strength aluminum alloy conductors for long-span applications according to claim 1, characterized in that, in Step 4, at this time, it is necessary to focus on controlling the casting temperature. Before casting, use an automatic temperature control device to control the casting temperature at 695 - 710 °C.

4. A preparation process for high-strength aluminum alloy conductors for long-span applications according to claim 1, characterized in that, In Step 5, the obtained aluminum rod adopts a quenching process. High-pressure quenching water is used to cool and clean the surface of the aluminum rod, reducing the temperature of the aluminum rod to 100 - 130°C. Meanwhile, a compressed air device is added at the end of the quenching water to blow dry the moisture on the surface of the aluminum rod with compressed air, and finally the temperature of the aluminum rod is controlled to 50 - 80°C.

5. The preparation process of a high-strength aluminum alloy wire for large-span use according to claim 1, characterized in that in Step 5, since the hardness of the aluminum rod billet is greater than that of the billet, the concentration of the emulsion is 2.5 times that for producing 1-series aluminum rods.

6. The preparation process of a high-strength aluminum alloy wire for large-span use according to claim 1, characterized in that in Step 6, the aging temperature is 150°C - 158°C, the heating-up time is 50 min - 70 min, and the heat preservation time is 360 min - 420 min.

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