Induction heating system for superhard aluminum

Abstract

The utility model relates to the technical field of induction heating systems, in particular to an induction heating system for super-duralumin, which comprises a preheating device, an induction heating device, two conveying components and a support table, and the two conveying components are arranged on two sides of the preheating device; the preheating device comprises a mounting base, an induction coil is arranged in the mounting base, a steel cylinder used for heating a bar is arranged in the induction coil, a heat insulation layer is arranged between the induction coil and the steel cylinder, the steel cylinder is a seamless steel cylinder, the steel cylinder is heated through the induction coil, the temperature of the steel cylinder is rapidly increased, and the bar is heated through the heat insulation layer. A high-temperature environment is formed in the inner cavity, and heat is conducted to the bar in the steel cylinder to preheat the bar, so that the material surface temperature difference during heating is reduced, the thermal stress is reduced, the risk of stress corrosion cracking is reduced, and the preheated bar is directly conveyed into the induction heating device through the conveying assembly to be subjected to gradient heating.

Description

Technical Field

[0001] The utility model relates to the technical field of induction heating systems, in particular to an induction heating system for super-hard aluminum. Background Art

[0002] Induction heating has become a common heating method in the aluminum alloy extrusion process because of its fast heating speed and ability to achieve gradient heating. However, super-hard aluminum alloys are prone to form non-precipitation zones during the heating process, causing intergranular corrosion and stress corrosion cracking, especially in the low-temperature range. Super-hard aluminum alloys are hard and prone to cracking; while in the high-temperature range, the hardness of aluminum alloys decreases and the risk of cracking decreases. Therefore, slow heating should be used for super-hard aluminum alloys in the low-temperature range to reduce the temperature difference on the material surface during heating, reduce thermal stress, and reduce the risk of stress corrosion cracking.

[0003] The existing method of heating super-hard aluminum at low temperature is generally to use a resistance furnace. The resistance furnace is a method of slow heating using hot air convection. Heating aluminum materials with a resistance furnace can reduce thermal stress and reduce the risk of stress corrosion cracking. For example, Chinese patent announcement No. CN213147402U discloses "a resistance furnace for producing aluminum silicate ceramic fibers". The door is opened by a handle, and the material is placed inside the shell. Multiple sets of heating elements are turned on to heat the material inside the shell, thereby reducing the pollution of the equipment to the environment and improving the convenience of adjusting the temperature inside the equipment.

[0004] However, the resistance furnace is large in size and requires a large space, which increases the site area and increases the cost of use. In addition, the heating speed of the resistance furnace is too slow to meet the requirements. The resistance furnace cannot achieve gradient heating and cannot meet the requirements of high-quality extrusion process. Therefore, designing a super-hard aluminum heating system with adjustable heating speed, gradient heating, high temperature uniformity and stability is the technical problem to be solved by the utility model. Utility Model Content

[0005] The utility model aims to solve the shortcomings of the prior art, such as large resistance furnace volume, increased site area, increased use cost, inability to achieve gradient heating, etc., and proposes an induction heating system for super-hard aluminum.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] An induction heating system for super-hard aluminum is designed, comprising a preheating device, an induction heating device, two conveying components and a support table, wherein the preheating device, the induction heating device and the two conveying components are all arranged on the support table, and the two conveying components are arranged on both sides of the preheating device;

[0008] The preheating device comprises a mounting seat, an induction coil is arranged in the mounting seat, a steel cylinder for heating the rod is arranged in the induction coil, a heat insulation layer is arranged between the induction coil and the steel cylinder, and the steel cylinder is a seamless steel cylinder.

[0009] Furthermore, the induction heating device comprises a multi-layer coil, and the multi-layer coil is externally connected to an IGBT variable frequency power supply.

[0010] Furthermore, the conveying assembly includes a mounting frame and a first guide wheel, and a motor that cooperates with the first guide wheel is fixedly arranged on one side of the mounting frame.

[0011] Furthermore, a threaded column is threadedly connected to the mounting frame, a connecting frame is provided at the lower end of the threaded column, and a second guide wheel is rotatably provided below the connecting frame.

[0012] Furthermore, guide grooves are provided on both sides of the mounting frame, and guide blocks matching with the guide grooves are fixedly provided on both sides of the connecting frame.

[0013] Furthermore, the first guide wheel and the second guide wheel are both provided with guide grooves matching with the rods.

[0014] The utility model proposes an induction heating system for super-hard aluminum, which has the following beneficial effects:

[0015] In the utility model, the steel cylinder is heated by an induction coil, so that the temperature of the steel cylinder itself rises rapidly, the inner cavity forms a high temperature environment, and the heat is transferred to the rod in the steel cylinder to preheat it, thereby reducing the temperature difference of the material surface during heating, reducing thermal stress, and reducing the risk of stress corrosion cracking. By setting a conveying component, the preheated rod is directly conveyed to the induction heating device for gradient heating, the heating speed is adjustable, and the temperature uniformity and stability are high;

[0016] Secondly, in the utility model, the first guide wheel cooperates with the motor to support the conveying of the rod, and a threaded column and a second guide wheel are provided. The threaded column is rotated to control the second guide wheel to move down and contact the rod, thereby limiting the position of the rod to prevent it from slipping during the conveying process, and the position of the second guide wheel can be adjusted so that the conveying assembly can convey rods of different diameters, thereby improving the scope of application. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of an induction heating system for super-hard aluminum proposed by the utility model;

[0018] Figure 2 It is a structural schematic diagram of the mounting seat of the utility model;

[0019] Figure 3 This is a schematic diagram of the structure of the first guide wheel of the utility model;

[0020] Figure 4 It is a schematic diagram of the enlarged structure of area A of the utility model.

[0021] In the figure: 1. preheating device; 11. mounting seat; 12. induction coil; 13. steel cylinder; 14. thermal insulation layer; 2. induction heating device; 21. multi-layer coil; 3. conveying assembly; 31. mounting frame; 311. first guide wheel; 312. motor; 32. threaded column; 33. connecting frame; 34. second guide wheel; 35. guide block; 36. guide groove; 4. support table. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0023] Reference Figure 1-4 , an induction heating system for super-hard aluminum, comprising a preheating device 1, an induction heating device 2, two conveying components 3 and a support table 4, wherein the preheating device 1, the induction heating device 2 and the two conveying components 3 are all arranged on the support table 4, and the two conveying components 3 are arranged on both sides of the preheating device 1;

[0024] The preheating device 1 includes a mounting base 11, in which an induction coil 12 is arranged, in which a steel cylinder 13 for heating the rod is arranged, and between the induction coil 12 and the steel cylinder 13, a heat insulating layer 14 is arranged. The steel cylinder 13 is a seamless steel cylinder. Conventional induction furnaces also have steel sleeves, but this steel sleeve has seams. Its function is to protect the coil and the heat insulating layer from being scratched. It cannot be directly heated by the electromagnetic field and only plays a protective role. In some embodiments, a furnace door can be installed at the inlet and outlet of the steel cylinder 13 to ensure higher thermal efficiency.

[0025] In the utility model, the seamless steel cylinder is heated by the induction coil 12, so that the temperature of the steel cylinder 13 itself rises rapidly. In addition, since the efficiency is low when induction heating is performed on materials with good conductivity and low resistivity (copper, aluminum), while the efficiency is high when induction heating is performed on high resistivity materials such as steel and nickel, the electrical efficiency of induction heating of the steel cylinder 13 is higher than that of direct induction heating of aluminum rods. The induction coil 12 is protected from high temperature by the provision of the heat insulation layer 14, a high temperature environment is formed in the inner cavity of the steel cylinder 13, and heat is transferred to the rods in the steel cylinder 13 through heat transfer (conduction, convection, radiation) to preheat them, thereby reducing the temperature difference of the material surface during heating, reducing thermal stress, and reducing the risk of stress corrosion cracking. After the preheating is completed, the rods are transported to the induction heating device 2 through the conveying assembly 3 for gradient heating, so that the heating speed is adjustable, and the temperature uniformity and stability are high. The induction coil 12 is formed by winding a hollow copper tube.

[0026] Furthermore, in this embodiment, the induction heating device 2 includes a multi-layer coil 21, and the multi-layer coil 21 is externally connected to an IGBT variable frequency power supply. The electromagnetic field of the multi-layer coil 21 directly generates induced eddy currents in the aluminum rod for heating. The coil formed by multi-layer winding improves the heating efficiency. The coil is divided into zones and each zone is independently controlled to achieve temperature gradient heating of the rod blank. An IGBT variable frequency power supply is used to make the currents in each zone have the same frequency and phase to avoid temperature changes at the junctions of the zones. The IGBT variable frequency power supply can achieve stepless voltage regulation and smooth power output.

[0027] Furthermore, in this embodiment, the conveying assembly 3 includes a mounting frame 31 and a first guide wheel 311. A motor 312 that cooperates with the first guide wheel 311 is fixedly provided on one side of the mounting frame 31. The first guide wheel 311 cooperates with the motor 312 to support the conveying of the rods.

[0028] It should be noted that, in the present embodiment, a threaded column 32 is threadedly connected to the mounting frame 31, a connecting frame 33 is provided at the lower end of the threaded column 32, a second guide wheel 34 is rotatably provided below the connecting frame 33, and the second guide wheel 34 contacts with the rod to limit the position, thereby facilitating the transportation of the rod and preventing it from slipping during transportation, and the position of the second guide wheel 34 can be adjusted so that the conveying assembly 3 can convey rods of different diameters, thereby improving the scope of application. In some embodiments, the upper end of the threaded column 32 is connected to a control device, such as a servo motor, or can be a hand wheel.

[0029] In addition, in some embodiments, guide grooves are provided on both sides of the mounting frame 31, and guide blocks 35 that cooperate with the guide grooves are fixedly provided on both sides of the connecting frame 33. The guide blocks 35 cooperate with the guide grooves to share the force applied to the connecting frame 33, thereby preventing the threaded column 32 from being bent due to excessive force.

[0030] In more detail, in some embodiments, the first guide wheel 311 and the second guide wheel 34 are both provided with guide grooves 36 that match the rods. The guide grooves 36 restrict the rods to prevent them from being deviated during transportation and unable to be transported to the preheating device 1 or the induction heating device 2.

[0031] Working mode: When working, the seamless steel cylinder is heated by the induction coil 12, so that the temperature of the steel cylinder 13 itself rises rapidly. In addition, since the efficiency of induction heating is low for materials with good conductivity and low resistivity (copper, aluminum), and the efficiency of induction heating is high for materials with high resistivity such as steel and nickel, the electrical efficiency of induction heating of the steel cylinder 13 is higher than that of direct induction heating of the aluminum rod. By setting the heat insulation layer 14 to prevent the induction coil 12 from being affected by high temperature, the inner cavity of the steel cylinder 13 forms a high temperature environment, and the heat is transferred to the inner cavity of the steel cylinder 13 by heat transfer (conduction, convection, radiation). The rods guided into the steel cylinder 13 are preheated, thereby reducing the temperature difference on the material surface during heating, reducing thermal stress, and reducing the risk of stress corrosion cracking. After the preheating is completed, the rods are conveyed to the induction heating device 2 for gradient heating through the conveying assembly 3. The first guide wheel 311 cooperates with the motor 312 to support and convey the rods, and the second guide wheel 34 contacts the rods to limit the position, which facilitates the conveying of the rods and prevents them from slipping during the conveying process. The position of the second guide wheel 34 can be adjusted so that the conveying assembly 3 can convey rods of different diameters.

[0032] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An induction heating system for super-hard aluminum, comprising a preheating device (1), an induction heating device (2), two conveying components (3) and a support platform (4), wherein the preheating device (1), the induction heating device (2) and the two conveying components (3) are all arranged on the support platform (4), characterized in that: The two conveying assemblies (3) are arranged on both sides of the preheating device (1); The preheating device (1) comprises a mounting seat (11), an induction coil (12) is arranged inside the mounting seat (11), a steel cylinder (13) for heating the rod is arranged inside the induction coil (12), a heat insulation layer (14) is arranged between the induction coil (12) and the steel cylinder (13), and the steel cylinder (13) is a seamless steel cylinder.

2. The induction heating system for superduralumin according to claim 1, characterized in that: The induction heating device (2) comprises a multi-layer coil (21), and the multi-layer coil (21) is externally connected to an IGBT variable frequency power supply.

3. The induction heating system for super-duralumin according to claim 1, characterized in that: The conveying assembly (3) comprises a mounting frame (31) and a first guide wheel (311); a motor (312) matching with the first guide wheel (311) is fixedly arranged on one side of the mounting frame (31).

4. The induction heating system for super-duralumin according to claim 3, characterized in that: A threaded column (32) is threadedly connected to the mounting frame (31), a connecting frame (33) is provided at the lower end of the threaded column (32), and a second guide wheel (34) is rotatably provided below the connecting frame (33).

5. The induction heating system for super-duralumin according to claim 4, characterized in that: Both sides of the mounting frame (31) are provided with guide grooves, and both sides of the connecting frame (33) are fixedly provided with guide blocks (35) matching with the guide grooves.

6. The induction heating system for super-duralumin according to claim 5, characterized in that: The first guide wheel (311) and the second guide wheel (34) are both provided with guide grooves (36) matching with the rods.

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