Automatic demolding device for metal lithium ingot

Abstract

This utility model discloses an automatic demolding device for lithium metal ingots, relating to the technical field of lithium metal processing equipment. Its purpose is to reduce the shrinkage cavities inside the ingot caused by the cooling and solidification process between the molten lithium and the mold. The proposed technical solution includes a hollow ingot mold base, a spiral cooling coil fitted at the lower end of the mold base, a spiral ceramic heating rod fitted at the upper end of the mold base, and a temperature sensor installed on the side wall of the mold base. The cooling coil is connected to the control system via an electric regulating valve, the ceramic heating rod is connected to the control system via a solid-state relay, and the temperature sensor is also connected to the control system. This utility model can monitor and precisely control the mold temperature in real time, meeting the temperature requirements of lithium metal ingots at different stages, significantly reducing shrinkage cavities in the lithium ingots, and ensuring the quality of the lithium ingots.

Description

Technical Field

[0001] This utility model relates to the technical field of lithium metal processing equipment, specifically to an automatic demolding device for lithium metal ingots. Background Technology

[0002] In the casting and production of lithium metal-related products, numerous technical challenges urgently need to be addressed, severely impacting product quality and production efficiency. For example, during the casting process, a significant temperature difference exists between the molten lithium and the mold. When the high-temperature molten lithium is injected into the relatively low-temperature mold, the lithium expands and contracts during solidification due to thermal expansion. This contraction leads to shrinkage cavities within the ingot, reducing its density and affecting the product's mechanical and physical properties. It may even pose safety hazards such as leaks during use.

[0003] Patent CN209792578U discloses a demolding optimization device for metal casting molds, including a support frame, a casting mold mounted on the support frame, and a heating device circumferentially disposed outside the casting mold. The casting mold includes a circular pipe for casting and shaping, with a forming cavity formed within the inner diameter of the circular pipe, and a demolding layer uniformly coated on the forming cavity. This invention achieves rapid demolding after metal casting by combining a demolding agent and heating, saving demolding time, improving demolding effect, and demonstrating strong overall practicality and reliability. Although this solution includes a heating device that heats the mold through combustion, because it only includes a heating structure, when the mold temperature is too high, the molten metal cannot cool down quickly, leading to shrinkage cavities in the metal during demolding due to excessive temperature differences. Utility Model Content

[0004] The purpose of this invention is to provide an automatic demolding device for lithium ingots, so as to reduce the phenomenon of shrinkage cavities inside the ingots that occur during the cooling and solidification process between the lithium liquid and the mold.

[0005] The technical solution of this utility model to solve the above-mentioned technical problems is as follows:

[0006] An automatic demolding device for lithium metal ingots includes a hollow ingot mold base, a spiral cooling coil fitted at the lower end of the ingot mold base, a spiral ceramic heating rod fitted at the upper end of the ingot mold base, a temperature sensor installed on the side wall of the ingot mold base, the cooling coil being connected to the control system via an electric regulating valve, the ceramic heating rod being connected to the control system via a solid-state relay, and the temperature sensor being connected to the control system.

[0007] Preferably, both the cooling coil and the ceramic heating rod are spiral-shaped.

[0008] Preferably, an aerogel insulation layer is provided between the cooling coil and the ceramic heating rod.

[0009] Preferably, a support plate for demolding lithium metal ingots is provided at the bottom of the ingot mold base.

[0010] Preferably, a hydraulic straight rod and multiple hydraulic auxiliary rods are provided between the pallet and the hydraulic ejection mechanism. The hydraulic straight rod is connected to the center of the pallet, and the multiple hydraulic auxiliary rods are arranged in a circumferential array on the side of the straight rod.

[0011] Preferably, a pressure sensor is embedded inside the hydraulic rod, and the pressure sensor is communicatively connected to the control system.

[0012] Preferably, the inner surface of the ingot mold substrate is provided with a boron nitride composite coating or a graphene composite coating.

[0013] This utility model has the following beneficial effects:

[0014] In this invention, a spiral cooling coil is provided at the lower end of the ingot mold base, and a spiral ceramic heating rod is provided at the upper end. A temperature sensor is located on the side wall and is connected to the control system. This allows for real-time monitoring and precise control of the mold temperature, meeting the temperature requirements of lithium ingots at different stages, significantly reducing shrinkage cavities in lithium ingots, and ensuring the quality of lithium ingots.

[0015] After casting, the lithium metal ingot can be smoothly removed from the mold using hydraulic ejection force, achieving automatic demolding, improving production efficiency, and reducing the difficulty and labor intensity of manual operation.

[0016] An aerogel insulation layer is installed between the cooling coil and the ceramic heating rod, which can effectively reduce heat loss and energy consumption, while ensuring the stability of the temperature inside the mold, which is beneficial to the molding of lithium metal ingots.

[0017] A hydraulic straight rod and multiple circumferentially arrayed hydraulic auxiliary rods are installed between the pallet and the hydraulic ejection mechanism, which can make the ejection force evenly distributed, ensuring that the lithium metal ingot is subjected to uniform force during demolding and avoiding damage to the ingot due to excessive local force.

[0018] The hydraulic rod is equipped with a pressure sensor that can monitor pressure changes in real time during the ejection process. When the pressure is abnormal, it can promptly feed back to the control system so that corresponding measures can be taken to prevent damage to the mold or ingot due to excessive pressure, and to ensure the safety and reliability of the demolding process.

[0019] The boron nitride or graphene composite coating applied to the inner surface of the ingot mold matrix has good lubricity and chemical stability, which can reduce the adhesion of metallic lithium to the inner surface of the mold, further improve the demolding effect, and extend the service life of the mold.

[0020] The spiral structure of the cooling coil and ceramic heating rod increases the contact area with the mold, improves heat exchange efficiency, and makes cooling or heating more uniform and rapid, which helps to improve the quality and production efficiency of lithium metal ingots. Attached Figure Description

[0021] Figures 1 to 3 This is a three-dimensional structural diagram of the present invention;

[0022] Figure 4 This is a cross-sectional view of the present invention;

[0023] Figure 5 This is a schematic diagram of the structure of the ingot mold base;

[0024] Figures 1 to 5 The reference numerals in the attached figures represent: 1-casting mold base, 2-cooling coil, 3-ceramic heating rod, 4-temperature sensor, 5-plate, 6-aerogel insulation layer, 7-pressure sensor, 8-hydraulic rod, 9-hydraulic auxiliary rod. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0026] In this utility model, the terms "longitudinal," "lateral," "vertical," "upper," "lower," "front," "rear," "left," "right," "top," and "bottom," etc., indicate the orientation or positional relationship based on the appendix. Figure 2 The orientation or positional relationship shown is for the purpose of describing the present invention only, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0027] Please refer to Figure 1-5 The present embodiment relates to an automatic demolding device for lithium metal ingots, in which each part works in concert to achieve automatic demolding of lithium metal ingots and reduce shrinkage cavities.

[0028] This device includes a hollow ingot mold base 1. A cooling coil 2 is fitted onto the lower end of the ingot mold base 1, and a ceramic heating rod 3 is fitted onto the upper end. A temperature sensor 4 is embedded in the side wall of the ingot mold base 1. The cooling coil 2 is connected to the control system via an electric regulating valve, and the ceramic heating rod 3 is connected to the control system via a solid-state relay. The temperature sensor 4 is also connected to the control system. The ingot mold base 1 is the core component of the entire device, and its interior has a hollow cylindrical structure. This hollow cylindrical structure provides space for the injection and molding of molten lithium metal. The ingot mold base 1 is made of high-strength, high-temperature resistant, and lithium corrosion-resistant materials, such as titanium alloy TC4 or 316L stainless steel. These two materials can maintain structural stability and integrity under the high-temperature environment of molten lithium metal, and are not easily deformed or damaged, thus ensuring the smooth progress of the ingot casting process. The dimensions of the ingot mold base 1 are determined according to actual production needs to meet the production requirements of lithium metal ingots of different specifications.

[0029] Temperature sensor 4 is embedded in the side wall of the ingot mold base 1. Temperature sensor 4 employs a high-precision thermocouple or resistance temperature detector (RTD) sensor, capable of measuring the temperature of the ingot mold base 1 accurately and in real time, and transmitting the temperature signal to the control system. Based on the received temperature signal, the control system precisely controls the operating status of the ceramic heating rod 3 and the cooling coil 2. For example, when temperature sensor 4 detects that the mold temperature is lower than the set value, the control system increases the heating power of the ceramic heating rod 3 to raise the mold temperature; when temperature sensor 4 detects that the mold temperature is higher than the set value, the control system accelerates the flow rate of the cooling medium to enhance the cooling effect, thereby ensuring that the lithium metal ingot solidifies and forms within a suitable temperature range.

[0030] Cooling coil 2 is fitted at the lower end of the ingot mold base 1. Cooling coil 2 is made of a metal material with good thermal conductivity, such as copper, which can quickly dissipate heat from the ingot mold base 1. A cooling medium, commonly water or cooling oil, circulates inside the cooling coil 2. The cooling medium circulates within the cooling coil 2, carrying away heat from the ingot mold base 1 through heat exchange, allowing the lithium metal ingot to cool and solidify rapidly within the mold. The flow rate and velocity of the cooling medium can be adjusted according to the specifications of the lithium metal ingot and the production process requirements. The control system, based on feedback from the temperature sensor 4, sends a signal to the electric regulating valve controlling the cooling coil 2, thereby adjusting the flow rate of the cooling medium within the cooling coil 2.

[0031] A ceramic heating rod 3 is fitted onto the upper end of the ingot mold base 1. The ceramic heating rod 3 has advantages such as high temperature resistance and uniform heating, enabling it to preheat the mold before the molten lithium is poured in, ensuring the mold reaches a suitable temperature and preventing rapid or uneven solidification of the molten lithium due to excessive temperature difference with the mold. The heating power of the ceramic heating rod 3 is selected based on the size of the ingot mold base 1 and the preheating requirements. During preheating, the control system calculates the required heating power using a PID algorithm and sends a pulse width modulation (PWM) signal to the solid-state relay (SSR) controlling the ceramic heating rod 3, adjusting the energizing time of the ceramic heating rod 3 to regulate the heating temperature.

[0032] In this embodiment, the structure of the ceramic heating rod 3 positioned above and the cooling coil 2 positioned below creates a vertical temperature gradient of "heating above and cooling below," causing the molten lithium metal to solidify gradually from the bottom upwards. This directional solidification reduces defects such as shrinkage porosity and gas bubbles, and improves the density and chemical homogeneity of the ingot.

[0033] Both the cooling coil 2 and the ceramic heating rod 3 have a spiral shape. To further increase the contact area, the cooling coil 2 and the ceramic heating rod 3 are designed in a spiral shape. On one hand, the spiral design of the cooling coil 2 increases the contact area between the cooling coil 2 and the ingot mold base 1, thereby improving cooling efficiency; on the other hand, the spiral design of the ceramic heating rod 3 also increases the contact area between the ceramic heating rod 3 and the ingot mold base 1, thereby improving heating efficiency.

[0034] An aerogel insulation layer 6 is provided between the cooling coil 2 and the ceramic heating rod 3. The aerogel insulation layer 6 has an extremely low thermal conductivity, effectively reducing heat transfer between the cooling coil 2 and the ceramic heating rod 3, thus improving energy efficiency. The thickness of the aerogel insulation layer 6 can be adjusted according to actual needs. By setting the aerogel insulation layer 6, the temperature inside the ingot mold substrate 1 can be made more uniform and stable, which is beneficial to the uniform solidification of the lithium ingot and also reduces production costs.

[0035] A support plate 5 for demolding lithium metal ingots is provided at the bottom of the ingot mold base 1. The bottom of the support plate 5 is connected to a hydraulic ejection mechanism. The support plate 5 has a circular structure that matches the ingot mold base 1, with a diameter slightly smaller than the inner diameter of the ingot mold base 1 to allow it to be smoothly placed at the bottom of the mold. The support plate 5 is made of a high-strength, wear-resistant material that does not chemically react with lithium metal, such as stainless steel. The function of the support plate 5 is to eject the lithium metal ingot upwards through the hydraulic ejection mechanism after it has solidified, thus separating the ingot from the mold. Due to the tensile properties of lithium liquid, there is no leakage of lithium liquid between the ingot mold base 1 and the support plate 5. The bottom of the support plate 5 is connected to the hydraulic ejection mechanism. The hydraulic ejection mechanism is the power source for the entire demolding device; it provides a sufficiently large ejection force to smoothly remove the lithium metal ingot from the mold. The hydraulic ejection mechanism mainly consists of a hydraulic pump, a hydraulic cylinder, and hydraulic oil pipes. The hydraulic pump draws hydraulic oil from the oil tank and delivers it to the hydraulic cylinder through the hydraulic oil pipe. The hydraulic cylinder generates linear motion under the action of the hydraulic oil, thereby pushing the pallet 5 to move upward.

[0036] A hydraulic straight rod 8 and multiple hydraulic auxiliary rods 9 are respectively installed between the pallet 5 and the hydraulic ejection mechanism. The hydraulic straight rod 8 is connected to the center of the pallet 5, and the multiple hydraulic auxiliary rods 9 are arranged in a circular array on the side of the straight rod 8. To ensure that the pallet 5 is subjected to uniform force during the lifting process, the hydraulic straight rod 8 and the hydraulic auxiliary rods 9 are installed between the pallet 5 and the hydraulic ejection mechanism. The hydraulic straight rod 8 and the multiple hydraulic auxiliary rods 9 push the pallet 5 through the lifting action of the hydraulic cylinder. The hydraulic straight rod 8 is connected to the center of the pallet 5, and its main function is to directly transmit the ejection force generated by the hydraulic ejection mechanism to the pallet 5, ensuring that the pallet 5 can move upward smoothly and evenly. The hydraulic straight rod 8 is made of high-strength alloy steel, which has sufficient rigidity and strength to withstand large ejection forces without deformation. The multiple hydraulic auxiliary rods 9 are arranged in a circular array on the side of the hydraulic straight rod 8. Their function is to assist the hydraulic straight rod 8 in its work, enhance the uniformity of force on the pallet 5 during the ejection process, and prevent the pallet 5 from tilting or swaying during the ascent. The number of hydraulic auxiliary rods 9 can be selected according to the size of the pallet 5 and the required jacking force.

[0037] A pressure sensor 7 is embedded inside the hydraulic rod 8, and the pressure sensor 7 is communicatively connected to the control system. To monitor the ejection resistance value of the support plate 5 in real time and prevent sudden changes in ejection resistance from affecting the lithium ingot, a pressure sensor 7 is embedded inside the hydraulic rod 8. The pressure sensor 7 is a high-precision strain gauge pressure sensor, capable of monitoring the pressure borne by the hydraulic rod 8 in real time and transmitting the pressure signal to the control system. Based on the received pressure signal, the control system adjusts the working state of the hydraulic ejection mechanism to ensure that the ejection force is evenly distributed on the support plate 5, avoiding damage to the lithium ingot during demolding due to uneven ejection force. For example, when the pressure value detected by the pressure sensor 7 is >1.5MPa, the control system automatically adjusts the flow rate and pressure of the hydraulic pump, and the hydraulic cylinder immediately executes a retraction-re-ejection strategy, retracting 3mm, pausing for 2 seconds, and then ejecting again. Simultaneously, the control system controls the ceramic heating rod 3 to heat the temperature to 120℃ to reduce the yield strength of the lithium ingot within the ingot mold matrix 1.

[0038] The inner surface of the ingot mold substrate 1 is coated with a boron nitride composite coating or a graphene composite coating. To reduce the contact area between molten lithium and the ingot mold substrate 1, a boron nitride composite coating or a graphene composite coating is applied to the inner surface of the ingot mold substrate 1. The boron nitride or graphene composite coating materials have the characteristic of withstanding high temperatures up to 800℃. Using laser engraving technology with a friction coefficient <0.2, the composite coating is uniformly applied to the inner surface of the ingot mold substrate 1. The shape of the composite coating is a micron-level honeycomb groove with a depth of 50-100μm. The boron nitride composite coating has excellent lubrication properties and chemical stability, which can reduce the friction between the molten lithium metal and the inner surface of the mold, preventing the lithium metal from sticking to the inner surface of the mold during solidification, thus facilitating the demolding of the lithium ingot. The graphene composite coating also has good lubrication properties and thermal conductivity, which can improve the fluidity and solidification uniformity of the molten lithium metal within the mold.

[0039] In actual production, the ceramic heating rod 3 is first activated to preheat the ingot mold base 1. The temperature sensor 4 monitors the mold temperature in real time and feeds the temperature signal back to the control system. Once the mold temperature reaches the set value, molten lithium metal is injected into the ingot mold base 1. During the solidification of the molten lithium metal, the cooling coil 2 starts working, and the cooling medium circulates within the coil, carrying away heat from the mold and allowing the lithium ingot to gradually cool and solidify. The temperature sensor 4 continuously monitors the mold temperature, and the control system adjusts the flow rate and velocity of the cooling medium according to temperature changes to ensure that the lithium ingot solidifies under a suitable temperature gradient. During the casting period, the ceramic heating rod 3 operates at full power to heat the temperature to 220°C, a process that takes approximately 10 seconds. During the feeding period, the cooling coil 2 is closed, maintaining the ingot mold base 1 at 200°C. Once the lithium ingot has completely solidified, the hydraulic ejection mechanism begins operation. The hydraulic pump delivers hydraulic oil to the hydraulic cylinder, which pushes the hydraulic rod 8 and hydraulic auxiliary rod 9 upwards, thereby causing the support plate 5 to eject the lithium ingot from the mold. During ejection, the pressure sensor 7 monitors the pressure on the hydraulic rod 8 in real time. The control system adjusts the operating state of the hydraulic ejection mechanism based on the pressure signal to ensure a smooth and stable ejection process. Finally, the lithium ingot is successfully demolded, completing the entire production process.

[0040] In this specific embodiment, the communication connection methods between the temperature sensor, pressure sensor, and control system include, but are not limited to, 4G, 5G, WiFi, and Bluetooth connections.

[0041] Through the coordinated work of the above components, the automatic demolding device for lithium metal ingots in this embodiment can achieve efficient and stable production of lithium metal ingots, improve product quality and production efficiency, and reduce production costs.

[0042] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An automatic demolding device for lithium metal ingots, comprising a hollow ingot mold base (1), characterized in that, The lower end of the ingot mold base (1) is fitted with a cooling coil (2), the upper end of the ingot mold base (1) is fitted with a ceramic heating rod (3), a temperature sensor (4) is embedded in the side wall of the ingot mold base (1), the cooling coil (2) is connected to the control system through an electric regulating valve, the ceramic heating rod (3) is connected to the control system through a solid-state relay, and the temperature sensor (4) is connected to the control system.

2. The automatic demolding device for lithium ingots according to claim 1, characterized in that, Both the cooling coil (2) and the ceramic heating rod (3) are spiral-shaped.

3. The automatic demolding device for lithium ingots according to claim 1, characterized in that, An aerogel insulation layer (6) is provided between the cooling coil (2) and the ceramic heating rod (3).

4. The automatic demolding device for lithium ingots according to claim 1, characterized in that, The bottom of the ingot mold base (1) is provided with a support plate (5) for demolding lithium metal ingots, and the bottom of the support plate (5) is connected to a hydraulic ejection mechanism.

5. The automatic demolding device for lithium ingots according to claim 4, characterized in that, A hydraulic straight rod (8) and multiple hydraulic auxiliary rods (9) are respectively provided between the pallet (5) and the hydraulic ejection mechanism. The hydraulic straight rod (8) is connected to the center of the pallet (5), and the multiple hydraulic auxiliary rods (9) are arranged in a circumferential array on the side of the straight rod (8).

6. The automatic demolding device for lithium ingots according to claim 5, characterized in that, A pressure sensor (7) is embedded inside the hydraulic rod (8), and the pressure sensor (7) is communicatively connected to the control system.

7. The automatic demolding device for lithium ingots according to any one of claims 1 to 6, characterized in that, The inner surface of the ingot mold substrate (1) is provided with a boron nitride composite coating or a graphene composite coating.

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