Aluminum alloy storage box bottom hot flanging temperature control device and control method

Abstract

The invention provides an aluminum alloy storage box bottom hot flanging temperature control device and method, and relates to the technical field of metal forming, the device comprises a flanging forming mechanism, a heating device, a temperature sensor and a control system; the flanging forming mechanism conducts flanging machining on the box bottom, the heating device is arranged in the flanging forming mechanism and heats the machining face of the box bottom, one end of the temperature sensor is connected with the compression spring, and the other end of the temperature sensor makes contact with the bottom face of the box bottom. The elastic force of the compression spring enables the temperature sensor to abut against the box bottom all the time, and the control system is electrically connected with the flanging forming mechanism, the heating device and the temperature sensor. According to the accurate control device and control method for the hot flanging temperature of the bottom of the aluminum alloy storage box, hot forming of local flanging of the bottom of the box is achieved through the heated mold, and the problem that cracking is prone to occurring during normal-temperature flanging forming is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of metal forming, and in particular, to a temperature control device and method for hot flanging of the bottom of an aluminum alloy storage tank. Background Art

[0002] As a high-strength and lightweight material, aluminum alloy is widely used in fields such as aerospace, rail transit, and the automotive industry. However, aluminum alloy has poor plasticity at room temperature and is difficult to form. Especially when performing local feature plastic forming on a formed aluminum alloy curved part, cracking is extremely likely to occur. Taking the bottom of the aluminum alloy storage tank of a launch vehicle as an example, the poor plasticity of aluminum alloy at room temperature combined with work hardening after drawing deformation results in reduced plasticity, and cracking defects are likely to occur during flanging at room temperature, causing part scrap.

[0003] Hot forming is an effective method to improve the plasticity and deformation ability of aluminum alloy. The traditional hot forming method is to place the blank in a heating furnace and heat it to a set temperature, and then transfer it to a mold to complete the forming. However, the diameter of the bottom part of the aluminum alloy storage tank exceeds 3 meters and the height exceeds 1 meter, making the overall heating difficult and inefficient.

[0004] To solve the above problems, the current technology uses a heating mold to locally heat the part where plastic deformation needs to occur through heat transfer. After the part temperature reaches the set temperature, the flanging operation is carried out. However, when aluminum alloy is formed at high temperature, the temperature and tissue properties change rapidly, and the interaction relationship between component deformation, tissue phase transformation, and mechanical properties is complex, making it difficult to control the tissue properties during the hot deformation process. If the temperature is too low during the heating process, the insufficient plastic improvement effect will lead to flanging cracking, and if the temperature is too high, it will lead to weakening of the performance at the flanging part of the part, not meeting the service performance. The existing temperature control method for hot flanging of the bottom is to arrange temperature sensors at the flanging position on the inner surface of the bottom. Due to interference with the punch, the temperature sensors need to be removed to perform the flanging action after the temperature reaches the set temperature. This method can only ensure precise temperature control of the part before flanging, and cannot realize the actual temperature measurement and temperature control of the deformation position during the flanging forming process. Therefore, how to achieve precise control of the local heating temperature of the bottom part is crucial, and it is urgent to solve the problem that the existing technology cannot achieve precise temperature control during the local hot flanging process of the bottom part. Summary of the Invention

[0005] Aiming at the defects in the prior art, the purpose of the present invention is to provide a temperature control device and method for hot flanging of the bottom of an aluminum alloy storage tank.

[0006] According to a temperature control device for hot flanging of the bottom of an aluminum alloy storage tank provided by the present invention, it includes: a flanging forming mechanism, a heating device, a temperature sensor, and a control system; The flanging forming mechanism performs flanging on the bottom of the box. The heating device is arranged in the flanging forming mechanism to heat the processing surface of the bottom of the box. One end of the temperature sensor is connected to the compression spring, and the other end contacts the bottom surface of the box. During the flanging process, the elastic force of the compression spring keeps the temperature sensor in tight contact with the bottom of the box all the time. The control system is electrically connected to the flanging forming mechanism, the heating device and the temperature sensor respectively.

[0007] Preferably, the flanging forming mechanism includes a female die, a male die and a hydraulic cylinder. The male die uses a positioning boss to center the pre-opened hole of the bottom of the box to the center of the female die, and the hydraulic cylinder drives the male die to perform flanging processing.

[0008] Preferably, the heating device is arranged in the female die and heats the bottom of the box through heat transfer.

[0009] Preferably, it further includes a temperature sensor guide plate; The temperature sensor is located in the temperature sensor guide plate, and the temperature sensor guide plate limits the elastic displacement of the temperature sensor.

[0010] Preferably, it further includes a thermometer, and the thermometer is electrically connected between the temperature sensor and the control system.

[0011] Preferably, the heating device is a heating resistor, a heating coil or an electromagnetic heater.

[0012] Preferably, the control system includes a programmable logic controller PLC, a signal input module, a communication module, a signal output module and a touch screen. The signal input module, the communication module, the signal output module and the touch screen are electrically connected to the programmable logic controller PLC respectively.

[0013] A method for controlling the temperature of hot flanging of the bottom of an aluminum alloy storage tank provided by the present invention includes: Step S1: Determine the sizes of the male and female dies and the specifications of the heating device according to the flanging size and profile on the bottom of the box; Step S2: Place the bottom of the box into the flanging forming mechanism, connect the male die to the hydraulic cylinder, use the positioning boss to make the bottom hole of the box at the center of the male and female dies, and make the lower surface of the box fit tightly with the female die; Step S3: Turn on the heating device to heat the female die, and heat the flanging position of the bottom of the box to the target temperature range through heat transfer; Step S4: The male die descends to the end of forming within a preset time. During the forming process, the power-on time of the heating device is adjusted in real time to keep the temperature of the flanging position of the bottom of the box within the target temperature range; Step S5: Turn off the heating device to complete the flanging processing.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The precise temperature control device and control method for hot flanging at the bottom of the aluminum alloy storage tank of the present invention use a heated mold to achieve local hot flanging and forming at the bottom of the tank, avoiding the problem of easy cracking during cold flanging and forming. 2. The precise temperature control device and control method for hot flanging at the bottom of the aluminum alloy storage tank of the present invention use a temperature sensor to measure the temperature at the flanging position of the bottom of the tank in real time, and transmit the temperature signal to the control system for feedback adjustment to achieve precise temperature control, avoiding the problems of cracking or performance weakening of the bottom of the tank caused by too low or too high temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Other features, objects, and advantages of the present invention will become more apparent by reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 It is a schematic diagram of the precise temperature control device for hot flanging at the bottom of the aluminum alloy storage tank in the present invention; Figure 2 It is a schematic diagram of the hot flanging and forming process at the bottom of the aluminum alloy storage tank in the present invention.

[0016] Description of the reference numerals: Female die 1, bottom of the tank 2, temperature sensor guide plate 3, male die 4, hydraulic cylinder 5, positioning boss 6, temperature sensor 7, compression spring 8, heating device 9, thermometer 10, control system 11. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several changes and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0018] Embodiment 1 As Figure 1 - Figure 2 shown: This embodiment provides a precise temperature control device for hot flanging at the bottom of an aluminum alloy storage tank, including a female die 1, a bottom of the tank 2, a temperature sensor guide plate 3, a male die 4, a hydraulic cylinder 5, a temperature sensor 7, a compression spring 8, a heating device 9, a thermometer 10, and a control system 11. The bottom of the tank 2 is installed between the male die 4 and the female die 1. The male die 4 is connected to the hydraulic cylinder 5, and the male die 4 is driven by the hydraulic cylinder 5 to move towards the female die 1 to perform flanging processing on the bottom of the tank 2. A heating device 9 is installed inside the female die 1. The temperature sensor 7 is in contact with the bottom of the tank 2. The heating device 9, the temperature sensor 7, the hydraulic cylinder 5, and the control system 11 are all electrically connected.

[0019] The bottom of the box 2 is fitted with the positioning boss 6 on the punch 4 through the pre-opened holes at the bottom of the box, and is precisely aligned with the die 1 by relying on the hydraulic cylinder 5. A displacement sensor is provided on the punch 4.

[0020] One end of the temperature sensor 7 is connected to the compression spring 8, and the other end is in contact with the bottom surface of the bottom of the box 2. During the flanging process, the elastic force of the compression spring 8 keeps the temperature sensor 7 always in tight contact with the bottom of the box 2. The temperature sensor guide plate limits the temperature sensor, and the temperature sensor 7 does not shift during the flanging process.

[0021] In a preferred embodiment, a thermometer 10 is provided on the temperature sensor circuit.

[0022] The heating device 9 is a thermal resistor, a heating coil or an electromagnetic heater, and the heating temperature can reach above 200 °C.

[0023] In this embodiment, the control system 11 includes a programmable logic controller PLC, a signal input module, a communication module, a signal output module and a touch screen. The signal input module, the communication module, the signal output module and the touch screen are electrically connected to the programmable logic controller PLC respectively. The hydraulic cylinder 5 and the heating device 9 are electrically connected to the signal output module respectively. The temperature sensor 7 and the displacement sensor are electrically connected to the signal input module.

[0024] The purpose of this embodiment is to improve the structure, and the control process of the control system 11 is the prior art.

[0025] The device for precisely controlling the temperature of the hot flanging of the bottom of the aluminum alloy storage tank in this embodiment uses the heating device 9 to heat the die 1. The bottom of the box 2 is placed on the heated die 1 and heated by heat transfer. Under the action of the temperature sensor guide plate 3 and the compression spring 8, the temperature sensor 7 can always be in contact with the bottom of the box 2 during the forming process, and the temperature signal is fed back to the control system 11. Through the coordinated control of the heating device 9 and the temperature sensor 7, temperature closed-loop control is achieved, solving the problem that the temperature of the local heating flanging of the bottom of the box cannot be precisely controlled, and avoiding the problems of cracking or performance weakening of the bottom of the box caused by too low or too high temperature.

[0026] Embodiment 2 This embodiment provides a method for precisely controlling the temperature of a device for precisely controlling the temperature of the hot flanging of the bottom of an aluminum alloy storage tank, including the following steps: Step S1, determine the size of the die 1, the size of the punch 4 and the specification of the heating device 9 according to the flanging size and profile on the bottom of the box 2; Step S2, place the bottom of the box 2 into the flanging forming mechanism. The punch 4 is connected to the hydraulic cylinder 5. Use the positioning boss 6 on the punch 4 to cooperate with the bottom hole on the bottom of the box 2 to make the bottom hole of the bottom of the box 2 concentric with the punch 4 and the die 1, and the lower surface of the bottom of the box 2 is closely attached to the die 1; Step S3: Install the heating device 9 in the female die 1 and start heating the female die 1. Heat the flanging position of the bottom of the box 2 to the target temperature of 175°C through heat transfer. Step S4: The punch 4 descends to the end of forming within 10 s. During the descent of the punch 4, the temperature sensor 7 remains in contact with the flanging position of the bottom of the box 2 for most of the stroke and separates until the flanging is in place. According to the temperature feedback by the temperature sensor 7, the power-on time of the heating device 9 is adjusted in real time to keep the temperature of the flanging position of the bottom of the box 2 within the range of 175 ± 5°C. Step S5: Turn off the heating device 9, open the die and take out the part of the bottom of the box 2 with flanging completed.

[0027] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0028] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined arbitrarily with each other.

Claims

1. A temperature control device for hot flanging of an aluminum alloy tank bottom, characterized in that: include: Flanging forming mechanism, heating device, temperature sensor and control system; The flanging forming mechanism performs flanging processing on the bottom of the box, and the heating device is arranged in the flanging forming mechanism to heat the processed surface of the bottom of the box. One end of the temperature sensor is connected to the compression spring, and the other end is in contact with the bottom surface of the bottom of the box. During the flanging process, the elastic force of the compression spring keeps the temperature sensor in close contact with the bottom of the box at all times. The control system is electrically connected to the flanging forming mechanism, the heating device and the temperature sensor respectively.

2. The aluminum alloy tank bottom hot flanging temperature control device according to claim 1 is characterized in that: The flanging forming mechanism comprises a die, a punch and a hydraulic cylinder. The punch uses a positioning boss to center the pre-opening of the box bottom to the center of the die, and the hydraulic cylinder drives the punch to perform flanging processing.

3. The aluminum alloy tank bottom hot flanging temperature control device according to claim 2 is characterized in that: The heating device is arranged in the concave mold to heat the box bottom through heat transfer.

4. The aluminum alloy tank bottom hot flanging temperature control device according to claim 1, characterized in that: Also included is a temperature sensor guide plate; The temperature sensor is located in a temperature sensor guide plate, and the temperature sensor guide plate limits the elastic displacement of the temperature sensor.

5. The aluminum alloy tank bottom hot flanging temperature control device according to claim 1, characterized in that: A temperature meter is also included, and the temperature meter is electrically connected between the temperature sensor and the control system.

6. The aluminum alloy tank bottom hot flanging temperature control device according to claim 1, characterized in that: The heating device is a heating resistor, a heating coil or an electromagnetic heater.

7. The aluminum alloy tank bottom hot flanging temperature control device according to claim 1, characterized in that: The control system includes a programmable logic controller (PLC), a signal input module, a communication module, a signal output module and a touch screen. The signal input module, the communication module, the signal output module and the touch screen are electrically connected to the programmable logic controller (PLC) respectively.

8. A method for controlling the temperature of the bottom of an aluminum alloy tank by hot flanging, based on the temperature control device for the bottom of an aluminum alloy tank by hot flanging according to any one of claims 1 to 7, characterized in that: include: Step S1: Determine the size of the male and female dies and the specifications of the heating device according to the size of the flange on the bottom of the box and the profile; Step S2: placing the box bottom into the flanging forming mechanism, connecting the male die to the hydraulic cylinder, using the positioning boss to make the bottom hole of the box bottom be in the center of the male and female dies, and the lower surface of the box bottom fits tightly with the female die; Step S3: Turn on the heating device to heat the concave mold, and heat the bottom flange position of the box to a target temperature range through heat transfer; Step S4: the punch moves downward within a preset time until the forming is completed, and the power-on time of the heating device is adjusted in real time during the forming process to keep the temperature at the bottom flange position of the box within the target temperature range; Step S5: Turn off the heating device to complete the flanging process.

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