Magnesium alloy low-pressure casting system and method based on safety protection device
By combining intelligent safety housing components with explosion-proof sand and magnesium alloy protective gas, the safety risks in the low-pressure casting process of magnesium alloys are solved, achieving efficient and safe casting production, reducing costs and energy consumption, and improving casting quality.
Patent Information
- Application Number
- CN202511556126.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-29
- Publication Date
- 2026-01-27
AI Technical Summary
The low-pressure casting process of magnesium alloys carries the risk of molten metal spillage and deflagration, which is difficult to prevent effectively with existing technologies, affecting production safety and cost efficiency.
The system employs an intelligent safety enclosure assembly in conjunction with specialized explosion-proof sand and magnesium alloy protective gas. By precisely adjusting the sand mold and the enclosure gap, and combining this with an intelligent control system, it achieves safe protection for molten metal.
It improves the safety and production efficiency of low-pressure casting, reduces production costs and energy consumption, and enhances the metallurgical quality of castings.
Smart Images
Figure CN121402601A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of low-pressure casting technology for magnesium alloys, and specifically relates to a low-pressure casting system and method for magnesium alloys based on a safety protection device. Background Technology
[0002] Magnesium alloy low-pressure casting refers to a precision casting process in which molten metal is driven to fill the mold steadily from bottom to top under pressure and solidifies under pressure. Its core lies in achieving high-quality and stable filling of magnesium alloy castings by precisely controlling pressure parameters and filling speed.
[0003] Before pouring in low-pressure casting, a pre-assembled sand mold must be placed on the casting base plate. Then, molten metal from the crucible is injected into the pre-assembled sand mold under pressure, and the solidification process of the casting is completed under anti-gravity conditions. Magnesium alloy low-pressure casting carries a certain risk of molten metal spillage and explosion during filling and solidification. Therefore, the pre-assembled sand mold must be placed in a safety enclosure, and the molten metal must be treated with flux protection to prevent fire and ensure safe production. Summary of the Invention
[0004] Objective: To provide a low-pressure casting system and method for magnesium alloys based on a safety protection device. This system can stabilize casting formation while improving the safety of low-pressure casting. By utilizing the high-precision matching between the intelligent safety housing component and sand molds of different sizes, the gap between the sand mold and the safety housing can be adjusted more precisely. Furthermore, through the synergistic protection of specialized explosion-proof sand and magnesium alloy protective gas, better fire and explosion prevention effects are achieved.
[0005] The fundamental purpose is to significantly reduce the ordering and manufacturing cycle of special safety casings, improve the safety of low-pressure casting, reduce production costs and energy consumption, shorten the casting production cycle, and improve the metallurgical quality of castings. Attached Figure Description
[0006] Figure 1 This is a schematic diagram of a low-pressure casting system for magnesium alloys based on a safety protection device; Figure 2 A side view of a magnesium alloy low-pressure casting system based on a safety protection device; Figure 3 This is a cross-sectional view of a magnesium alloy low-pressure casting system based on a safety protection device. Detailed Implementation
[0007] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.
[0008] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.
[0009] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.
[0010] This invention relates to a production process for magnesium alloy castings, including alloy smelting, low-pressure casting, anti-gravity filling, casting feeding, and casting solidification.
[0011] This invention relates to an intelligent safety protection device for low-pressure casting of magnesium alloys, such as... Figures 1-3 As shown, a safety box with automatically adjustable size, special explosion-proof sand, and magnesium alloy protective gas are used to form an intelligent safety protection device for low-pressure casting of magnesium alloy. The device includes an intelligent safety box component three-dimensional warehouse supply unit 1, a safety box module tooling retrieval unit 2, a robotic arm 3, a safety box combination plate 4, a crane 5, a pouring station 6, an automatic sand removal machine 7, a gas mixing cabinet 8, a sand mold protective gas circuit 9, explosion-proof sand 10, a melting crucible 11, a crucible protective gas circuit 12, a mechanical pump rotor 13, a riser pipe 14, and a safety box component 15.
[0012] A production process and intelligent safety protection method for low-pressure casting of magnesium alloys includes the following steps: Step 1: The magnesium alloy is smelted in the smelting crucible 11. During smelting, the crucible protective gas path 12 is opened, and SF6+CO2 magnesium alloy protective gas is introduced throughout the process to prevent the metal liquid from burning.
[0013] Step 2: Transport the assembled sand mold to the pouring area of the low-pressure casting equipment, open the sand mold protective gas path 9, and continuously supply magnesium alloy protective gas of SF6+CO2 to fill the sand mold cavity with protective gas, and use an oxygen content monitor to ensure that the oxygen content in the sand mold cavity is less than 15%.
[0014] Step 3: Input the structural features and dimensions of a certain type of casing casting into the intelligent safety box spare parts supply unit 1. The software intelligently matches the safety box dimensions and pre-assembles the safety box components. According to the safety standard that the assembled safety box is 10cm away from the outer surface of the sand mold, the operator performs a confirmation operation.
[0015] Step 4: Safety case module tooling retrieval unit 2 retrieves the required safety case accessories according to the instructions issued by the intelligent safety case spare parts supply unit 1. Step 5: Assemble the safety condom assembly onto the safety condom assembly plate 4 using robotic arm 3; Step 6: Use crane 5 to transport the assembled safety box to the pouring station 6, and fix the assembled safety box with the assembled sand mold; Step 7: Use the automatic sand removal machine 7 to fill the gap between the safety box and the sand mold with special explosion-proof sand 10. The special explosion-proof sand is a 1:1 mixture of large sand with a particle size of 10mm and 50 / 100 mesh Piper sand.
[0016] Step 8: Start the low-pressure casting equipment at casting station 6. Use the mechanical pump rotor 13 to inject the molten magnesium alloy liquid in the melting crucible 11 into the sand mold under anti-gravity conditions through the riser pipe 14. After the molten metal in the sand mold comes into contact with the limit signal line, adjust the speed of the mechanical pump to make the casting in the sand mold feed under gravity conditions. Keep it for a certain time to make it completely solidify, and the casting preparation is completed.
[0017] The variable safety condom spare parts automated storage and supply unit 1 has prepared safety condom components of different sizes and shapes, which can be used to build basic units of safety condoms of different sizes.
[0018] The present invention provides an intelligent safety protection device for low-pressure casting of magnesium alloys, which adopts a safety box with intelligently adjustable size, and the special explosion-proof sand and magnesium alloy protective gas work together to protect the process, which can significantly improve the safety factor of the low-pressure casting production process of magnesium alloys.
[0019] Example One feasible implementation involves a production process for a certain type of magnesium alloy casing casting, including alloy melting, low-pressure casting, anti-gravity filling, casting feeding, and casting solidification. Simultaneously, this invention relates to an intelligent safety protection device for low-pressure casting of magnesium alloys. This device employs a safety housing with automatically adjustable dimensions, and comprises specialized explosion-proof sand and magnesium alloy protective gas. The device includes an intelligent safety housing component automated storage and retrieval unit 1, a safety housing module tooling retrieval unit 2, a robotic arm 3, a safety housing combination plate 4, a crane 5, a casting station 6, an automatic sand removal machine 7, a gas mixing cabinet 8, a sand mold protective gas path 9, explosion-proof sand 10, a melting crucible 11, a crucible protective gas path 12, a mechanical pump rotor 13, a riser pipe 14, and a safety housing component 15.
[0020] Step 1: The material for a certain type of magnesium alloy casing casting is ZM6 alloy, with a composition of Mg-Nd-Zn-Zr. First, the protective gas passage 12 of the crucible is opened, and a mixture of SF6 and CO2 with a volume ratio of 1:99 is continuously introduced to provide flame-retardant treatment to the surface of the molten metal throughout the process. Then, pure Mg ingots are melted in the melting crucible 11. After the pure Mg ingots have melted, Mg-Nd master alloy, pure Zn ingots, and Mg-Zr master alloy are added. After all the metal in the melting crucible 11 has melted, refining and slag removal operations are performed. Subsequently, chemical composition testing is conducted. After confirming that the chemical composition meets the requirements of ZM6 alloy, the casting is allowed to stand for 20 minutes in preparation for pouring.
[0021] Step 2: Assemble the upper sand mold, middle sand mold, lower sand mold, and various types of cores for a certain type of magnesium alloy casing casting. Then, transport the assembled sand mold to the pouring area of the low-pressure casting equipment, open the sand mold protective gas passage 9, and continuously introduce magnesium alloy protective gas with a volume ratio of 1:99 of SF6+CO2 to fill the sand mold cavity. Use an oxygen content monitor to detect the oxygen content. If the oxygen content exceeds 15%, increase the gas flow rate to ensure that the oxygen content in the sand mold cavity is below 15%.
[0022] Step 3: Input the structural features and dimensions of a certain type of casing casting into the intelligent safety box spare parts supply unit 1. The software intelligently matches the safety box dimensions and pre-assembles the safety box components. According to the safety standard that the assembled safety box is 10cm away from the outer surface of the sand mold, the operator performs a confirmation operation.
[0023] Step 4: Safety case module tooling retrieval unit 2 retrieves the required safety case components according to the instructions issued by the intelligent safety case spare parts supply unit 1. Step 5: The robotic arm 3 assembles the safety condom assembly on the safety condom combination plate 4 according to a predetermined program. Safety condom assemblies of fixed height and different lengths are combined and locked using a locking structure. Step 6: Use crane 5 to transport the assembled safety box to the pouring station 6, and fix the assembled safety box with the assembled sand mold; Step 7: Using the automatic sand removal machine 7, fill the gap between the safety box and the sand mold with a 1:1 mixture of 10mm large-particle sand and 50 / 100 mesh Piper sand according to a fixed procedure. Step 8: Heat the riser tube 14 to 700℃ and keep it at that temperature for 30 minutes before pouring. The temperature of the riser tube should not be lower than 700℃ throughout the pouring process.
[0024] Step 9: Start the low-pressure casting equipment at casting station 6. Under the condition of nonlinear layered filling speed of 1-13 kg / s, use the mechanical pump rotor 13 to inject the molten magnesium alloy liquid in the melting crucible 11 into the sand mold under the condition of anti-gravity through the riser pipe 14. After the molten metal in the sand mold contacts the limit signal line, the low-pressure casting machine adjusts the mechanical pump speed to 700-800 r / min according to the predetermined program, holds the pressure for 700s, so that the casting in the sand mold is fed and held for a certain period of time to allow it to solidify completely. The casting preparation is completed.
[0025] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A low-pressure casting system for magnesium alloys based on a safety protection device, characterized in that: The system includes: platform; The cranes are installed at both ends of the platform's width. The pouring station is located on one side of the platform along its length. The automatic sand removal machine and gas mixing cabinet are located next to the platform and close to the pouring station. One end of the sand mold protective gas circuit is connected to the gas mixing cabinet, and the other end is connected to the casting station and the sand mold to be cast in the casting station. The sand mold to be poured is set up at the pouring station, and the safety box is set up around the sand mold; Explosion-proof sand is filled between the sand mold to be poured and the safety housing; The safety condom box combination plate is located on the other side of the platform's length direction; The safety box assembly supply unit and the safety box assembly retrieval unit are located next to the platform and close to the safety box assembly plate; The safety box assembly retrieval unit selects the safety box assembly from the safety box assembly supply unit using a robotic arm, assembles the safety box into a safety box on the safety box assembly plate, and then lifts it to the pouring station by a crane.
2. The system according to claim 1, characterized in that: The safety box assembly supply unit stores safety box assemblies of different sizes and shapes, forming a safety box that matches the sand mold.
3. The system according to claim 1, characterized in that: The system also includes a smelting crucible and a crucible protection gas path.
4. The system according to claim 1, characterized in that: The system also includes a mechanical pump rotor and a riser pipe.
5. A low-pressure casting method for magnesium alloys based on a safety protection device, implemented using the device according to any one of claims 1-4, characterized in that, Includes the following steps: Step 1: Melt ZM6 alloy liquid; Step 2: Assemble the upper sand mold, middle sand mold, lower sand mold, and various types of cores for the magnesium alloy casing casting, and then transport the assembled sand mold to the pouring station; Step 3: Input the sand mold structure features and dimensions into the safety box assembly supply unit. The safety box assembly supply unit selects the safety box assembly and performs pre-assembly on the display. After the operator confirms, proceed to the next step. Step 4: The safety case assembly retrieval unit selects the confirmed safety case assembly from the safety case assembly supply unit and assembles it into a safety case on the safety case assembly plate. Step 5: Use a crane to move the safety housing to the pouring position and place it around the sand mold; Step Six: Use an automatic sand removal machine to fill sand between the safety housing and the sand mold; Step 7: Pour the sand mold.
6. The method according to claim 5, characterized in that: ZM6 alloy has the composition Mg-Nd-Zn-Zr; During smelting, the protective gas path of the crucible is first opened and a mixture of SF6 and CO2 with a volume ratio of 1:99 is continuously introduced to prevent the molten surface from burning. Then, pure Mg ingots are melted in the smelting crucible. After the pure Mg ingots are melted, Mg-Nd master alloy, pure Zn ingots and Mg-Zr master alloy are added. After all the metal in the melting crucible has melted, refining and slag removal are carried out. Then, chemical composition testing is performed. Once the chemical composition requirements of ZM6 alloy are met, the mixture is left to stand for 20 minutes before casting.
7. The method according to claim 5, characterized in that: In step two, after the sand mold is transported to the casting station, magnesium alloy protective gas with a volume ratio of 1:99 (SF6 + CO2) is continuously introduced into the sand mold to fill the mold cavity until the oxygen content in the mold cavity is less than 15%.
8. The method according to claim 5, characterized in that: In step three, the distance between the outer surface of the sand mold and the safety box is 10cm ± 1cm.
9. The method according to claim 5, characterized in that: In step six, large-particle sand with a particle size of 10 mm is mixed with 50 / 100 mesh Piper sand at a ratio of 1:
1.
10. The method according to claim 5, characterized in that: In step seven, during casting, under the condition of nonlinear layered filling speed of 1~13kg / s, the molten magnesium alloy liquid in the melting crucible is injected into the sand mold through the riser pipe under the condition of anti-gravity using the rotor of the mechanical pump. After the molten metal in the sand mold contacts the limit signal line, the low-pressure casting machine adjusts the speed of the mechanical pump to 700r~800r / min according to the predetermined program, and holds the pressure for 700s, so that the casting in the sand mold is fed.