Horizontal continuous casting control method for copper-clad steel and horizontal continuous casting system for producing copper-clad steel

Abstract

The invention discloses a horizontal continuous casting control method for copper-clad steel and a horizontal continuous casting system for producing the copper-clad steel. The method comprises the steps that the level of molten copper contained in an inner cavity is kept at the level higher than a steel wire in a continuous casting furnace by a first preset height; the advancing of the steel wire is controlled, the steel wire is fed through a connector, enters a casting cavity of the crystallizer through an inner cavity of the melting furnace and then is discharged, and the total time length of the steel wire staying in the furnace from feeding to discharging is controlled so that the steel wire can be heated to a first set temperature when entering the casting cavity of the crystallizer; and the copper liquid in the inner cavity enters the casting cavity through the pouring hole of the crystallizer, so that the copper liquid is crystallized on the surface of the steel wire to form the copper-clad steel wire rod. The solution provided by the invention is beneficial to combination of the copper liquid and the surface of the steel wire, the coating effect of a copper layer on the surface of the steel wire is improved, and the continuous casting quality of the copper-coated steel wire is improved.

Description

Technical Field

[0001] The present disclosure relates to the field of metal continuous casting composite technology, and in particular to a horizontal continuous casting control method for copper-clad steel and a horizontal continuous casting system for producing copper-clad steel, and copper-clad steel wire produced thereby. Background Art

[0002] In the process of producing various steel products, there are two methods to use liquid metal solidification, namely traditional mold casting and continuous casting. Among them, the principle of continuous casting is: molten metal is continuously poured into the crystallizer and continuously pulled out from the other end of the crystallizer, which can obtain materials of any length or specific length.

[0003] Taking copper-clad steel material (also known as copper-clad steel) as an example, it is also called copper-clad steel bimetallic composite material. It is a composite conductor made of copper and steel through a special process. This conductor has the high strength, excellent elasticity, large thermal resistance and high magnetic conductivity of steel, as well as the good electrical conductivity and excellent corrosion resistance of copper. It is widely used in electrical and electronic fields.

[0004] In the production process of copper-clad steel materials, continuous casting, a core production link, is particularly critical to the quality and production efficiency of copper-clad steel products. However, there are multiple factors in the continuous casting production of copper-clad steel that will affect the quality and production efficiency of copper-clad steel products. The existing technology has not yet proposed an efficient and reliable copper-clad steel continuous casting production solution. Therefore, how to achieve high production efficiency, high yield rate and reliable and excellent product quality in the production of copper-clad steel is an urgent problem to be solved. Summary of the invention

[0005] One purpose of the present disclosure is to alleviate or eliminate the above-mentioned defects of the existing copper-clad steel continuous casting production technology, and to propose a horizontal continuous casting control method for copper-clad steel and a horizontal continuous casting system for producing copper-clad steel, as well as copper-clad steel wire produced thereby.

[0006] The present disclosure discloses a method for controlling horizontal continuous casting of copper-clad steel, which is characterized in that the continuous casting furnace comprises a melting furnace, a connector and a crystallizer, the melting furnace is provided with an inner cavity and an inlet and an outlet communicated with the inner cavity, the inlet of the melting furnace is plugged with the connector, the inner cavity is suitable for containing molten copper, the crystallizer is plugged with the outlet of the melting furnace, the part of the crystallizer located in the inner cavity is provided with a casting cavity and a pouring hole communicated with the casting cavity, the inner cavity is communicated with the pouring hole and the casting cavity, wherein the connector is used for feeding steel wire, and the crystallizer is used for discharging copper-clad steel wire;

[0007] The horizontal continuous casting control method comprises:

[0008] Maintaining the level of the molten copper contained in the inner cavity at a level higher than the steel wire in the continuous casting furnace by a first predetermined height, wherein the first predetermined height is not less than 5 centimeters;

[0009] Controlling the movement of the steel wire, feeding from the connector, passing through the inner cavity of the melting furnace into the casting cavity of the crystallizer and then discharging, wherein the total residence time of the steel wire in the furnace from feeding to discharging is controlled so that the steel wire is heated to a first set temperature when entering the casting cavity of the crystallizer, wherein the first set temperature is a temperature greater than the solidification and crystallization point of the copper liquid and is between 1120 and 1220° C., and the total residence time in the furnace is between 30 and 90 seconds;

[0010] The copper liquid in the inner cavity enters the casting cavity through the infusion hole of the crystallizer, so that the copper liquid is crystallized on the surface of the steel wire to form a copper-clad steel wire.

[0011] The technical solution proposed in the present disclosure can solve one of the defects in the prior art. The steel wire is appropriately heated to the first set temperature by the high temperature of the melting furnace, that is, the temperature is increased before entering the crystallizer to cast the copper layer, which is more conducive to the combination of the copper liquid and the steel wire surface, and the coating effect of the copper layer on the steel wire surface is improved, and the continuous casting quality of the copper-clad steel wire is improved. By using the cooperation of the melting furnace and the crystallizer, the high temperature of the melting furnace acts on the copper liquid and the steel wire at the same time, and the heat is fully utilized. In addition, the distance between the preheating and copper layer casting processes is shortened, ensuring that the steel wire enters the casting cavity of the crystallizer immediately after preheating, reducing the heat loss of the steel wire between the two processes. At the same time, proper heating still allows the copper layer to cool quickly after coating to complete the surface crystallization process, and further achieves better results in the energy efficiency of the continuous casting production of copper-clad steel.

[0012] According to some embodiments of the present disclosure, the horizontal continuous casting control method includes preheating the steel wire to a second set temperature via a preheating device before the steel wire enters the connector, and the second set temperature is between 300 and 800°C.

[0013] According to some embodiments of the present disclosure, controlling the travel of the steel wire includes:

[0014] The steel wire is controlled to be conveyed according to a set feeding strategy, wherein the set feeding strategy is a step-by-step conveying strategy that continuously and alternately conveys the steel wire at a set travel speed so that it travels a set step distance (it can also be understood that the strategy controls the set travel speed and indirectly controls the second set time for driving the steel wire to travel) and then stops conveying for a first set time, wherein the total residence time in the furnace is set according to the temperature difference between the temperature of the steel wire before it enters the connector and the first set temperature, the first set time is set according to the crystallization time of the copper liquid in the casting cavity on the surface of the steel wire, and the set step distance and the set travel speed are set in a mutually associated manner according to the inner cavity length, the total residence time in the furnace and the first set time.

[0015] Among them, it can be understood that the output frequency of the step-by-step conveying strategy is associated with the second set time and the first set time (the latter two determine the duration of a single output cycle), and the overall production speed of the copper-clad steel wire is associated with the total residence time in the furnace and the inner cavity length (the overall production speed can be calculated from the latter two, measured by the length of the copper-clad steel wire).

[0016] According to some embodiments of the present disclosure, the inner cavity length is between 20-40 cm, the total residence time in the furnace is between 40-60 seconds, and the overall production speed determined by the inner cavity length and the total residence time in the furnace is controlled within the range of 320 mm / min-540 mm / min.

[0017] According to some preferred embodiments of the present disclosure, the first predetermined height of the copper liquid contained in the inner cavity is maintained in the range of 10-20 cm, and its temperature is maintained in the range of 1150-1190° C., preferably in the range of 1165-1175° C.

[0018] It should be understood that the molten copper contained in the inner cavity needs to be coated on the surface of the steel wire in the casting cavity through the injection hole. Therefore, by setting the preferred first predetermined height range, the static pressure of the appropriate size that can be generated by the height of the molten copper level is used to ensure that the molten copper flows into the casting cavity through the injection hole at a desired or optimal flow rate under the action of the static pressure and crystallizes on the surface of the steel wire to form a copper-clad steel wire. In other words, the preferred first predetermined height can help the molten copper flow into the casting cavity and fully combine with the steel wire during the first set time period when the steel wire is stopped in the aforementioned step-by-step conveying strategy, thereby achieving better product quality of the copper-clad steel wire and avoiding product defects.

[0019] According to some preferred embodiments of the present disclosure, the horizontal continuous casting control method may further include:

[0020] Based on the desired overall production speed or target production speed, the travel speed of the steel wire and the temperature of the molten copper are adjusted accordingly. Specifically, when the overall production speed is controlled within the range of 320 mm / min to 540 mm / min and the desired overall production speed is increased, the travel speed of the steel wire is synchronously increased, and the temperature of the molten copper is slightly increased (within the range of 1150 to 1190° C.) in association therewith.

[0021] It should be understood that according to the horizontal continuous casting control method of the above-mentioned embodiment of the present disclosure, the continuous casting process of copper-clad steel is realized by implementing a stepping system in the link of pulling out the billet after the furnace. This stepping system provides the time required for the copper coating layer in the continuous casting furnace to solidify and performs the pull / stop cycle of the metal billet. Therefore, a stepping drive device such as a stepping motor is very suitable to serve as the active driving power source and realize the pulling out of the copper-clad steel billet in a stepping manner after the furnace. At the same time, since the front of the continuous casting furnace in the production line of copper-clad steel continuous casting may need to drive the steel to move forward continuously (for example, the uncoiling and straightening in the front process may require continuous power output to ensure the processing effect of its own link), there must be a certain degree of inconsistency in the upstream and downstream power systems in the production line. The horizontal continuous casting control method according to the above-mentioned preferred embodiment of the present disclosure can simultaneously achieve the following two important technical advantages through its specific settings for the continuous casting process: improving the continuous casting quality of copper-clad steel wire, so that the structural characteristics and conductive properties of the produced copper-clad steel wire are particularly suitable for (underground) electrical grounding grids such as those used in industrial facilities, and can also be suitable for the above-ground part of the grounding system or grounding grid or for lightning protection materials such as lightning rods, belts, nets, wires and lightning down conductors; improving the production yield of copper-clad steel wire or reducing or even eliminating the following defects that may occur in the product, such as the breaking and cracking of the steel wire and the copper infiltration caused by the cracking (a large amount of copper infiltrates the steel material), which may be caused by the aforementioned stepping power system for pulling out the billet after the furnace.

[0022] According to some embodiments of the present disclosure, the copper-clad steel wire is used for constructing an electrical grounding grid for industrial facilities, and the wire diameter cross-sectional area of ​​the copper-clad steel wire is in the range of 50-400 square millimeters.

[0023] According to some embodiments of the present disclosure, the horizontal continuous casting control method may further include:

[0024] Obtaining quality information of the copper-clad steel wire at the outlet of the crystallizer;

[0025] Determining that the quality information does not meet the (set) expected condition, regulating at least one of the traveling speed of the steel wire, the cooling medium flow rate of the connector, and the cooling medium flow rate of the crystallizer. Wherein, regulating at least one of the traveling speed of the steel wire, the cooling medium flow rate of the connector, and the cooling medium flow rate of the crystallizer may specifically include:

[0026] Based on the relationship between the current temperature of the copper liquid in the melting furnace and the first set temperature, at least one of the traveling speed of the steel wire and the flow rate of the cooling medium in the connector is regulated.

[0027] The present disclosure also provides a horizontal continuous casting system for producing copper-clad steel, wherein the horizontal continuous casting system comprises:

[0028] A continuous casting furnace, comprising a melting furnace, a connector and a crystallizer, wherein the melting furnace is provided with an inner cavity and an inlet and an outlet communicated with the inner cavity, wherein the inner cavity is suitable for containing molten copper, wherein the melting furnace has a rotating mechanism, and the rotating mechanism is configured to be able to operably rotate the melting furnace, so that the level of the molten copper contained therein is raised or lowered by tilting the inner cavity, and the level of the molten copper can be maintained at a level higher than a first predetermined height of a steel wire in the continuous casting furnace, wherein the first predetermined height is not less than 5 cm;

[0029] A connector, inserted into the inlet of the melting furnace and used for feeding the steel wire;

[0030] A crystallizer is inserted at the outlet of the melting furnace, wherein the portion of the crystallizer located in the inner cavity is provided with a casting cavity and a pouring hole connected to the casting cavity, the inner cavity is connected to both the pouring hole and the casting cavity, and the molten copper in the inner cavity can enter the casting cavity through the pouring hole of the crystallizer, so that the molten copper is crystallized on the surface of the steel wire to form a copper-clad steel wire to realize the discharge of the copper-clad steel wire;

[0031] A steel wire conveying device, wherein the steel wire conveying device is configured to control the movement of the steel wire, which is fed by the connector, passes through the inner cavity of the melting furnace, enters the casting cavity of the crystallizer, and then is discharged, wherein the total residence time of the steel wire in the furnace from feeding to discharging is controlled so that the steel wire is heated to a first set temperature when entering the casting cavity of the crystallizer, wherein the first set temperature is a temperature greater than the solidification and crystallization point of the copper liquid and is between 1120 and 1220°C, and the total residence time in the furnace is between 30 and 90 seconds.

[0032] According to some embodiments of the present disclosure, the horizontal continuous casting system further comprises:

[0033] A preheating device is arranged before the connector and is configured to preheat the steel wire to a second set temperature between 300 and 800°C.

[0034] According to some embodiments of the present disclosure, the steel wire conveying device includes a controller and a conveying component controlled by the controller, wherein the controller is configured with a set feeding strategy and is capable of controlling the conveying component to execute the set feeding strategy to convey the steel wire;

[0035] Among them, the set feeding strategy is a step-by-step conveying strategy that continuously and alternately conveys the steel wire at a set travel speed so that it travels a set step distance and then stops conveying for a first set time period, wherein the total residence time in the furnace is set according to the temperature difference between the temperature of the steel wire before it enters the connector and the first set temperature, the first set time period is set according to the crystallization time of the copper liquid in the casting cavity on the surface of the steel wire, and the set step distance and the set travel speed are set in a mutually associated manner according to the inner cavity length, the total residence time in the furnace and the first set time period.

[0036] According to some embodiments of the present disclosure, the inner cavity length is between 20-40 cm, the total residence time in the furnace is between 40-60 seconds, and the overall production speed determined by the inner cavity length and the total residence time in the furnace is controlled within the range of 320 mm / min-540 mm / min.

[0037] According to some embodiments of the present disclosure, the rotating mechanism is configured to operably rotate the melting furnace so that the level of the molten copper contained therein is maintained at a first predetermined height higher than the steel wire in the continuous casting furnace by tilting the inner cavity, and the melting furnace is configured to maintain the temperature of the molten copper contained therein within a range of 1150 to 1190°C, preferably within a range of 1165 to 1175°C.

[0038] According to some embodiments of the present disclosure, the conveying assembly includes a front-end pushing mechanism arranged in front of the connector and a rear-end pulling mechanism arranged behind the crystallizer, wherein the rear-end pulling mechanism includes a step-by-step second drive and a second transmission assembly, and is configured to enable the discharge of the copper-clad steel wire to be carried out according to a step-by-step conveying strategy, and the front-end pushing mechanism includes a continuous first drive and a first transmission assembly, wherein the first transmission assembly allows slippage between the first drive and the steel wire so that the first drive drives the steel wire to move in cooperation with the second drive.

[0039] According to some embodiments of the present disclosure, the copper-clad steel wire is used for constructing an electrical grounding grid for industrial facilities, and the wire diameter cross-sectional area of ​​the copper-clad steel wire is in the range of 50-400 square millimeters.

[0040] The present disclosure also provides a copper-clad steel wire produced by the horizontal continuous casting control method of the copper-clad steel described above or by the horizontal continuous casting system for producing copper-clad steel described above, wherein the copper-clad steel wire is composed of the following three parts from the inside to the outside in the radial direction: a steel core, a copper-steel transition layer and an outer copper clad layer;

[0041] Wherein, the content of other elements in the copper-steel transition layer except for the mixed copper and iron elements can be ignored, and the thickness of the copper-steel transition layer is in the range of 2-15 microns.

[0042] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present disclosure.

[0043] The positive and progressive effects of this disclosure are:

[0044] The horizontal continuous casting control method for copper-clad steel and the horizontal continuous casting system for producing copper-clad steel according to the present disclosure, as well as the copper-clad steel wire produced thereby, can, at least to a certain extent, combine the high production efficiency and high yield rate of the copper-clad steel wire with the reliable and excellent performance of the product itself. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a schematic structural diagram of a continuous casting furnace used in a horizontal continuous casting control method for copper-clad steel according to an embodiment of the present disclosure.

[0046] Figure 2 The composition level of the copper-steel transition zone of the copper-clad steel wire produced by the horizontal continuous casting control method of copper-clad steel according to a further preferred embodiment of the present disclosure is shown through scanning electron microscope analysis.

[0047] Description of reference numerals:

[0048] 31. Melting furnace; 311. Inner cavity; 32. Crystallizer; 321. Casting cavity; 322. Pouring hole; 33. Connector; 4. Preheating device; 8. Steel wire; 10. Liquid copper DETAILED DESCRIPTION

[0049] The preferred embodiments of the present disclosure are further described in detail below in conjunction with the drawings in the specification. The following description is exemplary and not limiting of the present disclosure. Any other similar situations also fall within the protection scope of the present disclosure.

[0050] In the following detailed description, directional terms, such as "left", "right", "up", "down", "front", "back", etc., are used with reference to the directions described in the drawings. The components of the embodiments of the present disclosure can be placed in a variety of different directions, and the directional terms are used for illustrative purposes rather than limiting.

[0051] Before describing the horizontal continuous casting control method of the copper-clad steel of the preferred embodiment of the present disclosure, the production process of the copper-clad steel is described first. After the steel is cut by the cutting mechanism, the processed steel wire enters the straightening mechanism for straightening, and after straightening, enters the polishing mechanism for polishing. After polishing, it is preheated by the preheating device and then enters the continuous casting furnace. The processed steel wire is coated with a copper layer in the continuous casting furnace, and the copper-clad steel wire is pulled out of the continuous casting furnace, and then the copper-clad steel wire is cooled by the cooling device, and the copper-clad steel process is completed.

[0052] refer to Figure 1 As shown, the continuous casting furnace includes a melting furnace 31 and a crystallizer 32. The melting furnace 31 is provided with an inner cavity 311 and an inlet and an outlet connected to the inner cavity 311. The inlet of the melting furnace 31 is plugged with a connector 33. The inner cavity 311 is suitable for accommodating molten copper 10. The crystallizer 32 is plugged at the outlet of the melting furnace 31. The part of the crystallizer 32 located in the inner cavity 311 is provided with a casting cavity 321 and a pouring hole 322. The inner cavity 311 is connected with the casting cavity 321 through the pouring hole 322, so that the steel wire 8 entering the inner cavity 311 through the connector 33 is passed through the casting cavity 321, and the copper liquid 10 enters the casting cavity 321 through the pouring hole 322 and is cast on the surface of the steel wire 8 to form a copper-clad steel wire.

[0053] Specifically, still refer to Figure 1 As shown, a method for controlling horizontal continuous casting of copper-clad steel according to an embodiment of the present disclosure includes:

[0054] The level of the copper liquid 10 contained in the inner cavity 311 is maintained at a level higher than the steel wire 8 in the continuous casting furnace by a first predetermined height, wherein the first predetermined height is not less than 5 cm;

[0055] Controlling the movement of the steel wire 8, feeding from the connector 33, passing through the inner cavity 311 of the melting furnace 31 and entering the casting cavity 321 of the crystallizer 32 and then discharging, wherein the total residence time of the steel wire 8 in the furnace from feeding to discharging is controlled so that the steel wire 8 is heated to a first set temperature when entering the casting cavity 321 of the crystallizer 32, wherein the first set temperature is a temperature greater than the solidification crystallization point of the copper liquid 10 and is between 1120 and 1220°C, and the total residence time in the furnace is between 30 and 90 seconds;

[0056] The copper liquid 10 in the inner cavity 311 enters the casting cavity 321 through the injection hole 322 of the crystallizer 32 , so that the copper liquid 10 is crystallized on the surface of the steel wire 8 to form a copper-clad steel wire.

[0057] The solution provided by the above-mentioned embodiment can appropriately heat the steel wire 8 to the first set temperature through the high temperature of the melting furnace 31, that is, to increase the temperature before entering the crystallizer 32 for copper coating, so as to be more conducive to the combination of the copper liquid 10 with the surface of the steel wire 8, improve the coating effect of the copper layer on the surface of the steel wire 8, and improve the continuous casting quality of the copper-clad steel wire. The cooperation between the melting furnace 31 and the crystallizer 32 allows the high temperature of the melting furnace 31 to act on the copper liquid 10 while also acting on the steel wire 8, so that the heat is fully utilized, and the distance between the two processes of preheating and copper casting is shortened, so as to ensure that the steel wire 8 immediately enters the casting cavity 321 of the crystallizer 32 as soon as possible after preheating, and reduce the heat loss of the steel wire 8 between the two processes. At the same time, proper heating still allows the copper layer to cool quickly after coating to complete the surface crystallization process, and further achieves better results in the energy efficiency of the continuous casting production of copper-clad steel.

[0058] According to some preferred embodiments of the present disclosure, the horizontal continuous casting control method includes preheating the steel wire 8 to a second set temperature via a preheating device 4 before the steel wire 8 enters the connector 33, and the second set temperature is between 300 and 800°C.

[0059] More specifically, before controlling the steel wire 8 to enter the inner cavity 311 of the melting furnace 31 from the inlet of the melting furnace 31 and preheating the steel wire 8 to a set temperature through the melting furnace 31, the following steps are further included:

[0060] Controlling the steel wire 8 to enter the preheating device 4 for initial preheating to a second set temperature;

[0061] The control steel wire 8 enters the connector 33 from the preheating device 4 .

[0062] In this embodiment, before the driving device drives the steel wire 8 to enter the melting furnace 31, the steel wire 8 first passes through the preheating device 4 to preheat the steel wire 8 for the first time, and then enters the inner cavity 311 of the melting furnace 31 for secondary heating. The steel wire 8 is heated to the second set temperature in the first preheating, and the steel wire 8 is heated to the first set temperature after the second preheating. The steel wire 8 is gradually heated during movement, which can extend the temperature increase path of the steel wire 8. When the traveling speed of the steel wire 8 is kept constant, the preheating temperature of the steel wire 8 reaches the requirement, ensuring the copper casting quality of the steel wire 8. At the same time, multiple preheating can keep the steel wire 8 at a certain traveling speed, avoiding the steel wire 8 from staying in one process for a long time for preheating to reach the preheating temperature requirement.

[0063] According to the horizontal continuous casting control method of the above embodiment of the present disclosure, the steel wire 8 is preheated to the first set temperature by the high temperature of the melting furnace 31, that is, the temperature is increased before entering the crystallizer 32 to cast the copper layer, which is more conducive to the combination of the copper liquid 10 with the surface of the steel wire 8, and the coating effect of the copper layer on the surface of the steel wire 8 is improved, and the continuous casting quality of the copper-clad steel wire is improved. By using the cooperation of the melting furnace 31 and the crystallizer 32, the high temperature of the melting furnace 31 acts on the copper liquid 10 and the steel wire 8 at the same time, and the heat is fully utilized, and the distance between the two processes of preheating and copper layer casting is shortened, ensuring that the steel wire 8 immediately enters the casting cavity 321 of the crystallizer 32 at the first time after preheating, reducing the heat loss of the steel wire 8 between the two processes. The copper liquid 10 directly enters the casting cavity 321 of the crystallizer 32 in the inner cavity 311 of the melting furnace 31, that is, the processes of melting copper, preheating the steel wire 8 and casting the copper layer are integrated into one through the continuous casting furnace, and the horizontal continuous casting control is more compact and integrated.

[0064] Moreover, the continuous casting furnace is based on the horizontal continuous casting process. The inlet and outlet of the melting furnace 31 are arranged relative to each other in the horizontal direction, and a crystallizer 32 is arranged at the outlet. The vertical lowest liquid level of the copper liquid 10 is located at the bottom of the melting furnace 31, and the vertical highest liquid level of the copper liquid 10 is above the crystallizer 32.

[0065] According to some preferred embodiments of the present disclosure, controlling the travel of the steel wire 8 includes:

[0066] The steel wire 8 is controlled to be conveyed according to a set feeding strategy, wherein the set feeding strategy is a step-by-step conveying strategy that continuously and alternately conveys the steel wire at a set travel speed so that it travels a set step distance and then stops conveying for a first set time, wherein the total residence time in the furnace is set according to the temperature difference between the temperature of the steel wire 8 before it enters the connector 33 and the first set temperature, the first set time is set according to the crystallization time of the copper liquid 10 on the surface of the steel wire 8 in the casting cavity 321, and the set step distance and the set travel speed are set in a mutually associated manner according to the length of the inner cavity 311, the total residence time in the furnace, and the first set time.

[0067] Among them, it can be understood that the output frequency of the step-by-step conveying strategy is associated with the second set time and the first set time (the latter two determine the duration of a single output cycle), and the overall production speed of the copper-clad steel wire can be calculated based on the total residence time in the furnace and the length of the inner cavity 311. The overall production speed is measured by the length of the copper-clad steel wire produced per unit time, and its unit is, for example, millimeters / minute used as follows.

[0068] According to some preferred embodiments of the present disclosure, the length of the inner cavity 311 is between 20 and 40 centimeters, the total residence time in the furnace is between 40 and 60 seconds, and the overall production speed determined by the length of the inner cavity 311 and the total residence time in the furnace is controlled within the range of 320 mm / min to 540 mm / min.

[0069] According to some further preferred embodiments of the present disclosure, the first predetermined height of the copper liquid 10 contained in the inner cavity 311 is maintained in the range of 10-20 cm, and its temperature is maintained in the range of 1150-1190° C., preferably in the range of 1165-1175° C.

[0070] According to a further preferred embodiment of the present disclosure, the horizontal continuous casting control method may further include:

[0071] Based on the desired overall production speed or target production speed, the travel speed of the steel wire and the temperature of the molten copper are adjusted accordingly. Specifically, when the overall production speed is controlled within the range of 320 mm / min to 540 mm / min and the desired overall production speed is increased, the travel speed of the steel wire is synchronously increased, and the temperature of the molten copper is slightly increased (within the range of 1150 to 1190° C.) in association therewith.

[0072] The horizontal continuous casting control method according to the above-mentioned preferred embodiment of the present disclosure can simultaneously achieve the following two important technical advantages through its specific settings for the continuous casting process: improving the continuous casting quality of copper-clad steel wire, so that the structural characteristics and conductive properties of the produced copper-clad steel wire are particularly suitable for (underground) electrical grounding networks such as those used in industrial facilities; improving the production yield of copper-clad steel wire or reducing or even eliminating the following defects that may occur in the product, such as the steel wire 8 being broken or cracked, and copper infiltration (a large amount of copper infiltrates the steel material) caused by cracking, which may be caused by the aforementioned stepping power system for pulling out the billet after the furnace.

[0073] The copper-clad steel wire produced by the horizontal continuous casting control method of copper-clad steel according to the above further preferred embodiment of the present disclosure is composed of the following three parts from the inside to the outside in the radial direction: a steel core, a copper-steel transition layer and an outer copper cladding layer; wherein, the content of other elements in the copper-steel transition layer (i.e., the copper-steel interpenetration layer) except for the mixed copper and iron elements is negligible, and the thickness of the copper-steel transition layer is in the range of 2-15 microns.

[0074] and, Figure 2 The composition level of the copper-steel transition zone of the copper-clad steel wire produced by this preferred method is specifically shown by scanning electron microscopy analysis, and it has the following characteristics:

[0075] (1) The transition zone of copper and steel basically contains only copper and iron elements but no nickel elements (the transition zone of the copper-steel composite formed by the electroplating process contains a large amount of nickel elements), and actually forms an interpenetration layer in which copper and steel molecules are intertwined with each other;

[0076] (2) The copper-steel transition layer contains relatively high proportions of copper and iron elements, and the thickness of the transition layer reaches about 20 microns. The thickness of this transition zone exceeds the thickness of the transition zone of the copper-clad steel wire produced by the production method of the prior art;

[0077] (3) The copper-clad steel wire has a relatively high hardness after rolling, and the Vickers hardness can reach about 130 or above.

[0078] The above characteristics (1)-(3) further make the copper-clad steel wire product have a strong bonding force between copper and steel, and it is not easy to cause copper layer peeling or copper-steel separation when subjected to external forces (such as bending). At the same time, this allows the copper-clad steel wire to be subsequently rolled and drawn to reduce the diameter of the product, and in this process, the copper layer and the steel layer can be deformed synchronously, especially due to the aforementioned better copper-steel bonding force. At the same time, the copper-clad steel wire product can also withstand the impact of high power frequency current without defects such as blistering and peeling, which is beneficial to the long-term reliability in industrial grounding applications.

[0079] For example, according to some preferred embodiments of the present disclosure, the copper-clad steel wire, especially the copper-clad steel product having the above characteristics (1)-(3), can be used for building an electrical grounding grid for industrial facilities, and the wire diameter cross-sectional area of ​​the copper-clad steel wire is preferably in the range of 50-400 square millimeters, or the diameter of the steel wire 8 is in the range of 10-50 millimeters, and optionally, for a wider range of underground electrical grounding grids for industrial facilities, the diameter of the steel wire 8 is preferably in the range of 12-18 millimeters.

[0080] A number of specific embodiments for further controlling the quality of the copper-clad steel wire rod based on the above-mentioned horizontal continuous casting control method embodiment will be further introduced below.

[0081] According to a further preferred specific embodiment of the present disclosure, the method for controlling horizontal continuous casting of copper-clad steel further includes:

[0082] Obtaining quality information of the copper-clad steel wire at the outlet of the crystallizer 32;

[0083] It is determined that the quality information does not satisfy the desired condition, and at least one of the travel speed of the steel wire 8, the flow rate of the cooling medium of the connector 33, and the flow rate of the cooling medium of the crystallizer 32 is adjusted.

[0084] In this embodiment, in the step of obtaining the quality information of the copper-clad steel wire output at the outlet of the crystallizer 32, a device for obtaining the quality information is installed at the outlet of the crystallizer 32 to ensure that the crystallizer 32 immediately obtains the quality information when outputting the copper-clad steel wire, so as to timely adjust the various devices of the copper-clad steel production line to ensure production accuracy and quality.

[0085] The quality information does not meet the expected conditions, that is, the quality of the copper-clad steel wire does not meet the standard, which can be understood as follows: 1. The copper layer thickness does not meet the set thickness requirements, such as the overall thickness of the copper layer does not meet the set thickness, or the local thickness of the copper layer does not meet the set thickness; 2. The crystallization quality of the copper layer does not meet the set requirements, such as uneven crystallization of the copper layer, cracks, slag inclusions, exposed steel, etc. Among them, the copper layer thickness and the copper layer crystallization are interrelated and independent of each other. Uneven copper layer thickness will lead to exposed steel, and poor copper layer crystallization quality will also lead to exposed steel.

[0086] The quality of the copper-clad steel wire is affected by various processing devices such as the melting furnace 31, the crystallizer 32, the preheating device 4 and the driving device. When it is determined that the quality of the copper-clad steel wire does not meet the standards, the melting furnace 31, the crystallizer 32, the preheating device 4 and the driving device are checked and adjusted to quickly adjust the quality of the copper-clad steel wire and ensure that the quality of the copper-clad steel wire meets the production requirements.

[0087] According to some embodiments of the present disclosure, in the horizontal continuous casting control method, if it is determined that the quality information does not meet the expected conditions, for example, it is determined that the copper layer thickness does not reach the set thickness or the copper layer crystallizes to produce at least one of the defects of cracks, slag inclusions, and exposed steel, then the travel speed of the steel wire is regulated, the steel wire feed position is adjusted, and the steel wire travel is stabilized to reduce irregular jitter of the steel wire).

[0088] The following is a description of an embodiment of a horizontal continuous casting system for producing copper-clad steel provided by the present disclosure. The horizontal continuous casting system for producing copper-clad steel described below and the better technical effects that can be achieved are understood and referenced in correspondence with the embodiment contents of the horizontal continuous casting control method for copper-clad steel described above.

[0089] Still reference Figure 1 As shown, the present disclosure also provides a horizontal continuous casting system for producing copper-clad steel, comprising:

[0090] A continuous casting furnace, comprising a melting furnace 31, a connector 33 and a crystallizer 32, wherein the melting furnace 31 is provided with an inner cavity 311 and an inlet and an outlet communicated with the inner cavity 311, wherein the inner cavity 311 is suitable for containing molten copper 10, wherein the melting furnace 31 has a rotating mechanism, and the rotating mechanism is configured to be able to operably rotate the melting furnace 31, so that the level of the molten copper 10 contained therein is raised or lowered by tilting the inner cavity 311, and the level of the molten copper 10 can be maintained at a level higher than a first predetermined height of a steel wire 8 in the continuous casting furnace, wherein the first predetermined height is not less than 5 cm;

[0091] A connector 33, inserted into the inlet of the melting furnace 31 and used for feeding the steel wire 8;

[0092] A crystallizer 32 is inserted at the outlet of the melting furnace 31. The portion of the crystallizer 32 located in the inner cavity 311 is provided with a casting cavity 321 and a pouring hole 322 communicating with the casting cavity 321. The inner cavity 311 is communicated with the pouring hole 322 and the casting cavity 321. The molten copper 10 in the inner cavity 311 can enter the casting cavity 321 through the pouring hole 322 of the crystallizer 32, so that the molten copper 10 crystallizes on the surface of the steel wire 8 to form a copper-clad steel wire to realize the discharge of the copper-clad steel wire.

[0093] A steel wire 8 conveying device, wherein the steel wire 8 conveying device is configured to control the movement of the steel wire 8, which is fed by the connector 33, passes through the inner cavity 311 of the melting furnace 31, and enters the casting cavity 321 of the crystallizer 32 and then is discharged, wherein the total residence time of the steel wire 8 in the furnace from feeding to discharging is controlled so that the steel wire 8 is heated to a first set temperature when entering the casting cavity 321 of the crystallizer 32, wherein the first set temperature is a temperature greater than the solidification and crystallization point of the copper liquid 10 and is between 1120 and 1220°C, and the total residence time in the furnace is between 30 and 90 seconds.

[0094] According to a preferred embodiment of the present disclosure, the horizontal continuous casting system further comprises:

[0095] The preheating device 4 is arranged before the connector 33 and is configured to preheat the steel wire 8 to a second set temperature, wherein the second set temperature is between 300 and 800°C.

[0096] According to a preferred embodiment of the present disclosure, the steel wire 8 conveying device includes a controller and a conveying component controlled by the controller, wherein the controller is configured with a set feeding strategy and is capable of controlling the conveying component to execute the set feeding strategy to convey the steel wire 8;

[0097] Among them, the set feeding strategy is a step-by-step conveying strategy that continuously and alternately conveys the steel wire at a set travel speed so that it travels a set step distance and then stops conveying for a first set time. Among them, the total residence time in the furnace is set according to the temperature difference between the temperature of the steel wire 8 before it enters the connector 33 and the first set temperature, the first set time is set according to the crystallization time of the copper liquid 10 on the surface of the steel wire 8 in the casting cavity 321, and the set step distance and the set travel speed are set in a mutually associated manner according to the length of the inner cavity 311, the total residence time in the furnace, and the first set time.

[0098] According to a preferred embodiment of the present disclosure, the length of the inner cavity 311 is between 20-40 cm, the total residence time in the furnace is between 40-60 seconds, and the overall production speed determined by the length of the inner cavity 311 and the total residence time in the furnace is controlled within the range of 320 mm / min-540 mm / min.

[0099] According to a preferred embodiment of the present disclosure, the rotating mechanism is configured to operably rotate the melting furnace 31, so that the level of the molten copper 10 contained therein is maintained at a first predetermined height higher than the steel wire 8 in the continuous casting furnace by tilting the inner cavity 311, and the melting furnace 31 is configured to maintain the temperature of the molten copper 10 contained therein within a range of 1150 to 1190°C, preferably within a range of 1165 to 1175°C.

[0100] According to a preferred embodiment of the present disclosure, the conveying assembly includes a front-end pushing mechanism arranged in front of the connector 33 and a rear-end pulling mechanism arranged behind the crystallizer 32, wherein the rear-end pulling mechanism includes a step-by-step second drive and a second transmission assembly, and is configured to enable the discharge of the copper-clad steel wire to be carried out according to a step-by-step conveying strategy, and the front-end pushing mechanism includes a continuous first drive and a first transmission assembly, wherein the first transmission assembly allows slippage with the steel wire 8 so that the first drive drives the steel wire 8 to move in a manner that cooperates with the second drive.

[0101] According to a preferred embodiment of the present disclosure, the copper-clad steel wire is used for building an electrical grounding grid for industrial facilities, and the diameter of the steel wire 8 is in the range of 10-50 mm.

[0102] The horizontal continuous casting system for producing copper-clad steel according to the above preferred embodiment of the present disclosure can also produce copper-clad steel with the above reference Figure 2 The properties or characteristics of the copper-clad steel wire are described, and the relevant contents will not be repeated here.

[0103] Although the specific embodiments of the present disclosure are described above, those skilled in the art should understand that these are only examples, and the protection scope of the present disclosure is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present disclosure, but these changes and modifications fall within the protection scope of the present disclosure.

Claims

1. A method for controlling horizontal continuous casting of copper-clad steel, characterized in that: The continuous casting furnace comprises a melting furnace, a connector and a crystallizer, wherein the melting furnace is provided with an inner cavity and an inlet and an outlet communicated with the inner cavity, the connector is inserted at the inlet of the melting furnace, the inner cavity is suitable for containing molten copper, the crystallizer is inserted at the outlet of the melting furnace, the part of the crystallizer located in the inner cavity is provided with a casting cavity and a pouring hole communicated with the casting cavity, the inner cavity is communicated with the pouring hole and the casting cavity, wherein the connector is used for feeding steel wire, and the crystallizer is used for discharging copper-clad steel wire; The horizontal continuous casting control method comprises: Maintaining the level of the molten copper contained in the inner cavity at a level higher than the steel wire in the continuous casting furnace by a first predetermined height, wherein the first predetermined height is not less than 5 centimeters; Controlling the movement of the steel wire, feeding from the connector, passing through the inner cavity of the melting furnace into the casting cavity of the crystallizer and then discharging, wherein the total residence time of the steel wire in the furnace from feeding to discharging is controlled so that the steel wire is heated to a first set temperature when entering the casting cavity of the crystallizer, wherein the first set temperature is a temperature greater than the solidification and crystallization point of the copper liquid and is between 1120 and 1220° C., and the total residence time in the furnace is between 30 and 90 seconds; The copper liquid in the inner cavity enters the casting cavity through the infusion hole of the crystallizer, so that the copper liquid is crystallized on the surface of the steel wire to form a copper-clad steel wire.

2. The method for controlling horizontal continuous casting of copper-clad steel according to claim 1, characterized in that: The horizontal continuous casting control method includes preheating the steel wire to a second set temperature via a preheating device before the steel wire enters the connector, and the second set temperature is between 300 and 800°C.

3. The method for controlling horizontal continuous casting of copper-clad steel according to claim 1 or 2, characterized in that: Controlling the movement of the steel wire includes: The steel wire is controlled to be conveyed according to a set feeding strategy, wherein the set feeding strategy is a step-by-step conveying strategy that continuously and alternately conveys the steel wire at a set travel speed so that the steel wire travels a set step distance and then stops conveying for a first set time period, wherein the total residence time in the furnace is set according to the temperature difference between the temperature of the steel wire before it enters the connector and the first set temperature, the first set time period is set according to the crystallization time of the copper liquid in the casting cavity on the surface of the steel wire, and the set step distance and the set travel speed are set in a mutually associated manner according to the inner cavity length, the total residence time in the furnace, and the first set time period.

4. The method for controlling horizontal continuous casting of copper-clad steel according to claim 3, characterized in that: The inner cavity length is between 20-40 cm, the total residence time in the furnace is between 40-60 seconds, and the overall production speed determined by the inner cavity length and the total residence time in the furnace is controlled within the range of 320 mm / min-540 mm / min.

5. The method for controlling horizontal continuous casting of copper-clad steel according to claim 4, characterized in that: The first predetermined height of the copper liquid contained in the inner cavity is maintained in the range of 10-20 cm, and the temperature thereof is maintained in the range of 1150-1190° C., preferably in the range of 1165-1175° C.

6. The method for controlling horizontal continuous casting of copper-clad steel according to claim 5, characterized in that: The copper-clad steel wire is used for constructing an electrical grounding grid for industrial facilities, and the wire diameter cross-sectional area of ​​the copper-clad steel wire is in the range of 50-400 square millimeters.

7. A horizontal continuous casting system for producing copper-clad steel, characterized in that: The horizontal continuous casting system comprises: A continuous casting furnace, comprising a melting furnace, a connector and a crystallizer, wherein the melting furnace is provided with an inner cavity and an inlet and an outlet communicated with the inner cavity, wherein the inner cavity is suitable for containing molten copper, wherein the melting furnace has a rotating mechanism, and the rotating mechanism is configured to be able to operably rotate the melting furnace, so that the level of the molten copper contained therein is raised or lowered by tilting the inner cavity, and the level of the molten copper can be maintained at a level higher than a first predetermined height of a steel wire in the continuous casting furnace, wherein the first predetermined height is not less than 5 cm; A connector, inserted into the inlet of the melting furnace and used for feeding the steel wire; A crystallizer is inserted at the outlet of the melting furnace, wherein the portion of the crystallizer located in the inner cavity is provided with a casting cavity and a pouring hole connected to the casting cavity, the inner cavity is connected to both the pouring hole and the casting cavity, and the molten copper in the inner cavity can enter the casting cavity through the pouring hole of the crystallizer, so that the molten copper is crystallized on the surface of the steel wire to form a copper-clad steel wire to realize the discharge of the copper-clad steel wire; A steel wire conveying device, wherein the steel wire conveying device is configured to control the movement of the steel wire, which is fed by the connector, passes through the inner cavity of the melting furnace, enters the casting cavity of the crystallizer, and then is discharged, wherein the total residence time of the steel wire in the furnace from feeding to discharging is controlled so that the steel wire is heated to a first set temperature when entering the casting cavity of the crystallizer, wherein the first set temperature is a temperature greater than the solidification and crystallization point of the copper liquid and is between 1120 and 1220°C, and the total residence time in the furnace is between 30 and 90 seconds.

8. The horizontal continuous casting system for producing copper-clad steel according to claim 7, characterized in that: The horizontal continuous casting system also includes: A preheating device is arranged before the connector and is configured to preheat the steel wire to a second set temperature between 300 and 800°C.

9. The horizontal continuous casting system for producing copper-clad steel according to claim 7 or 8, characterized in that: The steel wire conveying device comprises a controller and a conveying component controlled by the controller, wherein the controller is configured with a set feeding strategy and can control the conveying component to execute the set feeding strategy to convey the steel wire; Among them, the set feeding strategy is a step-by-step conveying strategy that continuously and alternately conveys the steel wire at a set travel speed so that it travels a set step distance and then stops conveying for a first set time period, wherein the total residence time in the furnace is set according to the temperature difference between the temperature of the steel wire before it enters the connector and the first set temperature, the first set time period is set according to the crystallization time of the copper liquid in the casting cavity on the surface of the steel wire, and the set step distance and the set travel speed are set in a mutually associated manner according to the inner cavity length, the total residence time in the furnace and the first set time period.

10. The horizontal continuous casting system for producing copper-clad steel according to claim 9, characterized in that: The inner cavity length is between 20-40 cm, the total residence time in the furnace is between 40-60 seconds, and the overall production speed determined by the inner cavity length and the total residence time in the furnace is controlled within the range of 320 mm / min-540 mm / min.

11. The horizontal continuous casting system for producing copper-clad steel according to claim 10, characterized in that: The rotating mechanism is configured to operably rotate the melting furnace so that the level of the molten copper contained therein is maintained within a range of 10-20 cm by tilting the inner cavity at a first predetermined height higher than the steel wire in the continuous casting furnace, and the melting furnace is configured to maintain the temperature of the molten copper contained therein within a range of 1150-1190° C., preferably within a range of 1165-1175° C.

12. The horizontal continuous casting system for producing copper-clad steel according to claim 9, characterized in that: The conveying assembly includes a front-end pushing mechanism arranged in front of the connector and a rear-end pulling mechanism arranged behind the crystallizer, wherein the rear-end pulling mechanism includes a step-by-step second driver and a second transmission assembly, and is configured to enable the discharge of the copper-clad steel wire to be carried out according to a step-by-step conveying strategy, and the front-end pushing mechanism includes a continuous first driver and a first transmission assembly, wherein the first transmission assembly allows slippage between the first driver and the steel wire so that the first driver drives the steel wire to move in cooperation with the second driver.

13. The horizontal continuous casting system for producing copper-clad steel according to claim 12, characterized in that: The copper-clad steel wire is used for constructing an electrical grounding grid for industrial facilities, and the wire diameter cross-sectional area of ​​the copper-clad steel wire is in the range of 50-400 square millimeters.

14. A copper-clad steel wire produced by a horizontal continuous casting control method for copper-clad steel according to any one of claims 1 to 6 or a copper-clad steel wire produced by a horizontal continuous casting system for producing copper-clad steel according to any one of claims 7 to 13, characterized in that: The copper-clad steel wire is composed of the following three parts from inside to outside in the radial direction: a steel core, a copper-steel transition layer and an outer copper clad layer; Wherein, the content of other elements in the copper-steel transition layer except for the mixed copper and iron elements can be ignored, and the thickness of the copper-steel transition layer is in the range of 2-15 microns.

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