A casting device and a degassing and casting method

Abstract

The application discloses a casting device and a degassing and casting method. The casting device comprises a connecting pipe, the connecting pipe comprises a first connecting pipe, a second connecting pipe and a curved pipe, one end of the first connecting pipe is connected to the bottom of a crucible, the other end of the first connecting pipe is connected to the curved pipe, the curved pipe is overlapped on the outer wall of the crucible, one end of the second connecting pipe is connected to the end of the curved pipe which is away from the first connecting pipe, the other end of the second connecting pipe is connected to the bottom of a casting mold, and the end of the second connecting pipe which is connected to the casting mold is provided with a discharge port; a liquid storage pipe is connected to one end of the connecting pipe; and at least one vacuum pump is connected to the liquid storage pipe and the inner cavity of a shell. The application solves the problem that the molten metal pouring casting method causes the cast ingot to contain a large number of micro pores.

Description

Technical Field

[0001] This invention relates to the field of metal degassing and casting technology, and in particular to a casting apparatus and a degassing and casting method. Background Technology

[0002] Copper, aluminum, tin, and their alloys are often used to make various types of wires due to their unique properties and excellent plasticity. Most wires are produced through extrusion and drawing. Existing manufacturing processes mostly involve alloy smelting, casting into ingots, extrusion, and drawing. During the wire drawing process, the presence of pores in the wire often leads to breakage, significantly impacting production efficiency. The presence of pores also causes a large amount of molten droplet splashing during use, increasing wire loss. Furthermore, it restricts the development of wires towards smaller diameters and higher quality to meet the trend of high-quality manufacturing.

[0003] Therefore, the key to solving the problem of porosity in wire lies in eliminating porosity in the ingot. In actual production, it can be found that after degassing and slag removal during the smelting stage, the tilting casting method is generally used. This process reintroduces a large amount of gas into the melt, resulting in a large number of tiny pores still existing in the ingot after the melt solidifies. Summary of the Invention

[0004] Therefore, the present invention provides a casting apparatus and a degassing and casting method, which solves the problem that a large amount of gas is reintroduced into the melt during the molten metal casting process, resulting in the ingot containing a large number of tiny pores.

[0005] To address the aforementioned problems, the present invention provides a casting apparatus, comprising: a base; a housing disposed on the base, forming an inner cavity between the housing and the base, wherein heating elements are evenly distributed along the circumference of the inner cavity; a crucible placed on the base and located within the inner cavity of the housing; a casting mold cavity formed on the base and communicating with the inner cavity of the housing, the casting mold cavity being located on at least one side of the crucible; a casting mold disposed within the casting mold cavity, wherein a casting port is provided between the casting mold and the inner cavity of the housing; and a connecting pipe comprising a first connecting pipe, a second connecting pipe, and a bent pipe, one end of the first connecting pipe being connected to the inner cavity of the housing. At the bottom of the crucible, the other end of the first connecting pipe is connected to the bent pipe, which overlaps the outer wall of the crucible. One end of the second connecting pipe is connected to the end of the bent pipe away from the first connecting pipe, and the other end of the second connecting pipe leads to the bottom of the mold. The end of the second connecting pipe leading to the mold is provided with a discharge port. A liquid storage pipe is provided, with one end of the liquid storage pipe connected to the second connecting pipe. At least one vacuum pump is provided, which connects the liquid storage pipe and the inner cavity of the shell. At least one air inlet pipe and at least one air extraction pipe are provided. The air inlet pipe is used to introduce gas into the inner cavity of the shell, and the air extraction pipe is connected to the vacuum pump and is used to extract the pressure in the inner cavity of the shell.

[0006] Compared with existing technologies, the technical effects achieved by this solution are as follows: A sealed cavity is formed between the base and the shell, improving sealing and preventing air from entering the cavity, thus enhancing degassing. The mold cavity is located on at least one side of the crucible, and the mold is placed within the mold cavity, ensuring that the molten metal in the crucible can smoothly enter the mold. The vacuum pump, through the extraction pipe, creates a negative pressure in the cavity, allowing gas to escape from the molten metal. The first connecting pipe extends to the bottom of the crucible, preventing impurities such as scum from the solution surface from entering the mold, which is unavoidable in the tilting casting method. The combined use of the connecting pipe, the storage pipe, and the vacuum pump ensures that the gas pressure in the connecting pipe and the storage pipe is lower than the gas pressure in the cavity, allowing the molten metal in the crucible to continuously enter the mold through the connecting pipe, preventing the ingot from containing numerous micropores due to a large amount of gas entering the melt during casting.

[0007] Furthermore, the liquid storage tube includes: a first space and a second space; the first space is connected to one end of the second connecting tube near the curved tube, and the second space is connected to the vacuum pump.

[0008] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: the first space is used to contain the metal solution that enters due to the pressure difference, and the second space is used to prevent the metal solution from entering the vacuum pump, thus avoiding the situation where the metal solution enters the vacuum pump when the vacuum pump is working.

[0009] Furthermore, the connecting pipe includes a sealing device, which is located near the end of the second connecting pipe leading to the mold and is higher than the bottom of the mold cavity.

[0010] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: The sealing device can prevent the metal solution from leaking into the mold during the process of passing through the connecting pipe and the storage pipe due to the pressure difference, thus preventing it from hindering subsequent normal operation. It can also isolate the connecting pipe from the inner cavity of the shell, thereby effectively forming a pressure difference. When there is enough metal solution required in the mold, the sealing device can achieve the effect of a flow limiting switch, preventing excess metal solution from entering the mold through the connecting pipe.

[0011] Furthermore, a valve is provided on the air inlet pipe and the air extraction pipe.

[0012] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: the valve is used to control the entry and exit of gas in the inlet pipe and the extraction pipe, and can also be opened later to introduce inert gas into the inner cavity of the housing for degassing or cooling during the metal casting process; the valve can be opened on the branch line where multiple vacuum pumps are located to control the on and off of each vacuum pump, thereby realizing the difference in gas pressure between the inner cavity of the housing and the connecting pipe.

[0013] Furthermore, the connecting pipe also includes: a sensing device, disposed in the first space near the bottom of the first space;

[0014] The first space and the second space have a connecting port, which is higher than the sensing device. When the molten metal accumulates in the first space and submerges the sensing device, the sensing device receives a signal and shuts down the vacuum pump and the valve.

[0015] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: the first space and the second space have a communication port, and the communication port is set higher than the sensing device to prevent the metal solution from entering the second space, ensuring that the vacuum pump can work correctly. The sensing device opens when the metal solution enters the first space and exerts pressure on the sensing device. When the sensing device opens, the vacuum pump and the valve are closed to prevent too much metal solution from entering the first space and overflowing into the second space, keeping the connecting pipe full of metal solution.

[0016] Furthermore, the base includes a sealing ring, which is disposed around the contact area between the base and the housing and is embedded in the base and / or the housing.

[0017] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: after the sealing ring is attached to the base and the shell, it ensures the sealing of the inner cavity of the shell and ensures the realization of the negative pressure environment in the inner cavity of the shell.

[0018] This invention provides a casting method, implemented by the casting apparatus provided in any of the above embodiments, comprising:

[0019] Step S1: Place a solid metal in the crucible, extract the gas from the inner cavity of the shell using the vacuum pump, start the heating element, and begin metal melting to obtain a molten metal.

[0020] Step S2: Turn on the vacuum pump to draw the molten metal in the crucible into the connecting pipe and the storage pipe; the molten metal in the crucible and the molten metal in the connecting pipe flow into the mold;

[0021] Step S3: Cooling completes the casting process;

[0022] The shell is fitted with the base, and heating elements are evenly distributed in the circumferential direction within the shell cavity.

[0023] Compared with existing technologies, the technical effects achieved by this solution are as follows: Through step S1, on the one hand, by creating a negative pressure within the shell cavity, the solubility of gas in the molten metal can be reduced, thereby reducing the gas content in the molten metal; on the other hand, based on the principle of partial pressure difference, by reducing the surface pressure of the molten metal, the gas dissolved in the molten metal is continuously released from the melt, achieving a significant degassing effect, which is particularly effective for low-melting-point, easily absorbing alloys such as aluminum alloys and Babbitt metals. Furthermore, the generated bubbles, during their ascent, can adsorb non-metallic inclusions and carry them out of the molten metal, thus having a certain impurity removal effect. Under negative pressure conditions, the oxidation tendency of the molten metal can be reduced, resulting in a significant anti-oxidation effect. Through step S2, casting is performed using the siphon principle. The first connecting pipe enters the bottom of the crucible, and the other end of the second connecting pipe leads to the bottom of the mold, avoiding the situation where impurities such as scum on the solution surface are poured into the mold, which is unavoidable in traditional tilting casting methods. It also prevents the problem of gas continuously being drawn into the melt during the tilting casting process.

[0024] Furthermore, a ceramic rod is provided at the top of the shell, and the ceramic rod extends into the crucible; step S1 includes:

[0025] Step S11: Place the solid metal into the crucible;

[0026] Step S12: Connect the housing to the base;

[0027] Step S13: Turn on the vacuum pump to reduce the pressure inside the housing cavity;

[0028] Step S14: Activate the heating element to raise the temperature inside the shell cavity and begin metal melting, while simultaneously rotating the ceramic rod;

[0029] Step S15: The inner cavity of the shell is under negative pressure, and the air bubbles inside the metal solution continuously escape from the metal solution under the action of the pressure difference;

[0030] Step S16: The ceramic rod is removed from the metal solution, kept warm, and the bubbles inside the metal solution are allowed to disappear to complete the degassing process and obtain the metal solution.

[0031] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: the metal solid is completely melted to obtain a metal solution through step S1. The arrangement of the heating elements makes the heating process more stable and reliable. The ceramic rod stirs the metal solution, which is beneficial to metal melting and also helps to accelerate the discharge of gas. Before melting, a vacuum pump is used to maintain a negative pressure state, so that the air bubbles inside the metal solution continuously escape from the metal solution under the action of the pressure difference. The process of the ceramic rod being pulled away will also remove impurities from the metal solution, thus purifying the metal solution. After the holding time, most of the air bubbles inside the metal solution disappear, thereby preventing defects such as porosity from appearing in the ingot after casting.

[0032] Furthermore, the liquid storage tube includes: a first space, a second space, and a sensing device, wherein the sensing device is located in the first space near the bottom of the first space; the connecting tube includes: a sealing device, wherein the sealing device is located near the end of the connecting tube leading to the mold;

[0033] Step S1 includes: in S1, a vacuum pump extracts gas from the inner cavity of the housing to a first pressure value P1;

[0034] Step S2 includes:

[0035] Step S21: The vacuum pump extracts the gas in the connecting pipe and the liquid storage pipe until the pressure value in the connecting pipe and the liquid storage pipe is less than the first pressure value P1;

[0036] Step S22: The sensing device detects that the metal solution in the first space has submerged the sensing device. The sensing device triggers and controls the sealing device to open, and the metal solution enters the mold from the crucible through the connecting pipe.

[0037] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: the pressure value in the connecting pipe and the liquid storage pipe is less than the first pressure value P1, the metal solution is drawn from the crucible to the liquid storage pipe and the connecting pipe; the sensing device triggers and controls the sealing device to open, the metal solution enters the mold from the crucible through the connecting pipe, and through these steps, the metal solution can smoothly and continuously enter the mold from the crucible through the connecting pipe, thereby achieving uninterrupted casting and preventing the problem of casting speed being too fast or too slow.

[0038] Furthermore, the housing is provided with an air inlet pipe for introducing gas, an exhaust pipe for discharging gas, and a cooling layer for introducing cooling water.

[0039] Step S3 includes:

[0040] Step S31: Introduce cooling gas into the housing through the intake pipe and open the exhaust pipe;

[0041] Step S32: Cooling water is introduced into the cooling layer, and the temperature inside the shell cavity is allowed to decrease.

[0042] Step S33: Lift the shell, then lift the mold and flip it over so that the finished product inside the mold can be removed from the mold.

[0043] Compared with existing technologies, the technical effects achieved by this solution are as follows: cooling gas is introduced into the inner cavity of the shell, the exhaust pipe is opened, and water is simultaneously circulated through the cooling layer of the shell to accelerate the cooling of the inner cavity and improve production efficiency. Once the temperature inside the shell has dropped to a suitable level, the shell is lifted, and then the mold is lifted and flipped to complete the ingot demolding, obtaining the finished ingot. This step improves the stability of the finished ingot.

[0044] By adopting the technical solution of the present invention, the following technical effects can be achieved:

[0045] (1) The vacuum pump creates a negative pressure in the inner cavity of the shell through the suction pipe, allowing gas to escape from the molten metal. The combined use of the connecting pipe, the liquid storage pipe, and the vacuum pump ensures that the gas pressure in the connecting pipe and the liquid storage pipe is lower than the gas pressure in the inner cavity of the shell. This allows the molten metal in the crucible to continuously enter the mold through the connecting pipe under the siphon principle, preventing gas from re-entering the melt during casting and resulting in very few pores in the ingot.

[0046] (2) The first connecting pipe enters the bottom of the crucible, avoiding the situation where impurities such as scum on the surface of the solution are poured into the mold, which is unavoidable in the traditional pouring casting method.

[0047] (3) By using the vacuum pump to evacuate the inner cavity of the housing through the evacuation port, a negative pressure is formed in the inner cavity of the housing, which can reduce the solubility of gas in the molten metal, thereby reducing the gas content in the molten metal.

[0048] (4) On the other hand, based on the principle of partial pressure difference, by reducing the surface pressure of the molten metal, the gas dissolved in the molten metal is continuously released from the melt, which plays a significant role in degassing. This is particularly effective for low-melting-point alloys that are prone to gas absorption, such as aluminum alloys and Babbitt alloys. Furthermore, the generated bubbles can adsorb non-metallic inclusions and carry them out of the molten metal during their upward movement, thus having a certain impurity removal effect. Under negative pressure conditions, it can reduce the oxidation tendency of the molten metal and has a significant anti-oxidation effect. Attached Figure Description

[0049] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 This is a schematic diagram of a casting device provided in the first embodiment of the present invention.

[0051] Figure 2 for Figure 1 A schematic diagram of the connecting pipe.

[0052] Figure 3 for Figure 1 A schematic diagram of the structure of the central liquid storage pipe.

[0053] Figure 4 for Figure 1 A schematic diagram of the structure of the middle shell and the base.

[0054] Figure 5 for Figure 4 A schematic diagram of the structure of the ceramic rod.

[0055] Figure 6 for Figure 1 A schematic diagram of the structure of the casting mold.

[0056] Figure 7 This is a schematic flowchart of a casting method provided in the second embodiment of the present invention.

[0057] Explanation of reference numerals in the attached figures:

[0058] 100 - A casting apparatus; 110 - Shell; 111 - Cooling layer; 112 - Inner cavity of the shell; 113 - Mold cavity; 114 - Mold; 115 - Air inlet pipe; 116 - Air extraction pipe; 117 - Exhaust pipe; 120 - Base; 121 - Crucible; 130 - Connecting pipe; 131 - Liquid sealer; 132 - First connecting pipe; 133 - Second connecting pipe; 134 - Bend pipe; 140 - Liquid storage pipe; 141 - First space; 142 - Second Space; 143-Sensing device; 144-Connecting port; 150-Vacuum pump; 151-Oxygen partial pressure gauge; 152-Vacuum gauge; 160-Valve; 170-Sealing ring; 180-Ceramic rod; 190-High temperature resistant glass; 210-First motor; 211-Second motor; 220-Insulation material; 230-Refractory material; 240-Ceramic material; 250-Storage tray; 260-Lifting hole; 270-Temperature sensor; 280-Heating element. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] [First Embodiment]

[0061] See Figure 1-6The first embodiment of the present invention provides a casting device 100, comprising: a base 120; a shell 110 disposed on the base 120, forming an inner cavity 112 between the shell 110 and the base 120, wherein heating elements 280 are evenly distributed along the circumferential direction in the inner cavity 112; a crucible 121 placed on the base 120 and located in the inner cavity 112; a casting mold cavity 113 formed in the base 120 and communicating with the inner cavity 112, the casting mold cavity 113 being disposed on at least one side of the crucible 121; a casting mold 114 disposed in the casting mold cavity 113, wherein a casting port is provided between the casting mold 114 and the inner cavity 112; and a connecting pipe 130, comprising a first connecting pipe 132, a second connecting pipe 133, and a bent pipe 1. 34. One end of the first connecting pipe 132 leads to the bottom of the crucible 121, and the other end of the first connecting pipe 132 is connected to the bent pipe 134, which overlaps the outer wall of the crucible 121. One end of the second connecting pipe 133 is connected to the end of the bent pipe 134 away from the first connecting pipe 132, and the other end of the second connecting pipe 133 leads to the bottom of the mold 114. The end of the second connecting pipe 133 leading to the mold 114 is provided with a discharge port. A liquid storage pipe 140 is connected to the connecting pipe 130 at one end. A vacuum pump 150 is connected to the liquid storage pipe 140 and the inner cavity 112 of the shell. An air inlet pipe 115 and an air extraction pipe 116 are connected. The air inlet pipe 115 is used to introduce gas into the inner cavity 112 of the shell, and the air extraction pipe 116 is connected to the vacuum pump 150 and is used to extract the pressure in the inner cavity 112 of the shell.

[0062] In this embodiment, a sealed inner cavity 112 is formed between the base 120 and the shell 110, achieving a seal to prevent air from entering the inner cavity 112, thereby improving the degassing effect. A mold cavity 113 is formed on at least one side of the crucible 121, and a mold 114 is disposed within the mold cavity 113, ensuring that the molten metal in the crucible 121 can smoothly enter the mold 114. A vacuum pump 150, through a suction pipe 116, creates a negative pressure state in the inner cavity 112, allowing gas to escape from the molten metal. The first connecting pipe 130... The connecting pipe 132 extends to the bottom of the crucible 121, avoiding the situation where impurities such as scum on the surface of the solution are poured into the mold 114, which is unavoidable in the traditional pouring casting method. The combined use of the connecting pipe 130, the liquid storage pipe 140 and the vacuum pump 150 ensures that the gas pressure in the connecting pipe 130 and the liquid storage pipe 140 is lower than the gas pressure in the inner cavity 112 of the shell. This allows the molten metal in the crucible 121 to continuously enter the mold 114 through the connecting pipe 130, avoiding the problem of a large amount of gas entering the melt during the casting process, which would result in the ingot containing a large number of tiny pores.

[0063] Preferably, multiple vacuum pumps 150 can be used to adapt to the different negative pressure levels required by various alloys. A mechanical vacuum pump 150 can be used first to establish a preliminary negative pressure, and then a diffusion vacuum pump 150 can be used to further adjust the negative pressure so that the device can meet the melting environment of various alloys. There can be multiple heating elements 280 evenly distributed around the inner cavity 112 of the shell to fully heat the inner cavity 112 of the shell, thereby realizing the melting of solid metals. There is at least one inlet pipe 115 and one exhaust pipe 116. Multiple inlet pipes 115 and multiple exhaust pipes 116 improve the efficiency of the negative pressure process. In case one or more inlet pipes 115 or exhaust pipes 116 are damaged, there are backup inlet pipes 115 or exhaust pipes 116 to ensure the stability of the negative pressure environment.

[0064] In one specific embodiment, a casting apparatus 100 further includes: an oxygen partial pressure gauge 151, a vacuum gauge 152, and a temperature sensor 270. The oxygen partial pressure gauge 151 and the vacuum gauge 152 are connected to the inner cavity of the housing to detect the pressure value of the inner cavity 112. The temperature sensor 270 is connected to the inner cavity of the housing to detect the temperature value of the inner cavity 112, so as to facilitate the adjustment of the temperature of the heating element 280 and thereby regulate the temperature of the inner cavity 112, so that the temperature of the inner cavity 112 can adapt to the different melting temperatures of various metals.

[0065] Preferably, the housing 110 is further provided with heat insulation material 220, which is arranged around the inner wall of the housing 110 to prevent the heat dissipation during the metal smelting process from affecting the housing 110.

[0066] Preferably, the base further includes: refractory material 230 and ceramic material 240. The refractory material 230 is disposed between the mold cavity 113 and the mold 114. The refractory material 230 is used to prevent the heat dissipation during the metal smelting process from affecting the base 120. The ceramic material 240 has a certain strength and is resistant to high temperature and is used to place the crucible 121.

[0067] Preferably, the top of the housing 110 is also provided with a high-temperature resistant glass 190 and a lifting hole 260. The high-temperature resistant glass 190 is used to observe the working conditions inside the housing 110. The top edge of the housing 110 is provided with multiple lifting holes 260. When it is necessary to lift the housing 110, a fixing device can be inserted into the lifting hole 260 to lift the housing 110. The setting of multiple lifting holes 260 makes the lifting of the housing 110 more stable and less likely to cause the housing 110 to tip over or slip during lifting.

[0068] In one specific embodiment, the liquid storage tube 140 includes, for example, a first space 141 and a second space 142; the first space 141 is connected to one end of the second connecting tube 133 near the bent tube 134, and the second space 142 is connected to the vacuum pump 150.

[0069] Specifically, the first space 141 is used to contain the metal solution that enters due to the pressure difference. The first space 141 and the second space 142 have a communication port 144 at the top to ensure that the vacuum pump 150 can work correctly and also to prevent the metal solution from entering the second space 142, thereby affecting the vacuum pump 150 and causing the vacuum pump 150 to malfunction.

[0070] In one specific embodiment, the connecting pipe 130 includes, for example, a sealing device 131, which is located near the end of the second connecting pipe 133 leading to the mold 114 and is higher than the bottom of the mold cavity 113 relative to the bottom of the mold 114.

[0071] Specifically, the sealing device 131 can prevent the molten metal from leaking into the mold 114 during the process of the molten metal flowing through the connecting pipe 130 and the storage pipe 140 due to the pressure difference, thereby hindering the subsequent normal operation. It can also isolate the connecting pipe 130 from the inner cavity 112 of the housing, thereby effectively forming a pressure difference. When there is enough molten metal in the mold 114, the sealing device 131 can achieve the effect of a flow limiting switch, preventing excess molten metal from entering the mold 114 through the connecting pipe 130.

[0072] In one specific embodiment, valve 160 is provided on air inlet pipe 115 and air extraction pipe 116.

[0073] Specifically, valve 160 is used to control the entry and exit of gas in inlet pipe 115 and exhaust pipe 116. It can also be used to open valve 160 in inlet pipe 115 to introduce inert gas into inner cavity 112 of housing for degassing or cooling during metal casting process. Valve 160 can be opened on branch lines of multiple vacuum pumps 150 to control the working relationship of each branch line, thereby achieving the difference in gas pressure between inner cavity 112 of housing and connecting pipe 130.

[0074] In one specific embodiment, the liquid storage tube 140 may further include, for example, a sensing device 143 disposed at the bottom of the first space 141; wherein, there is a communication port 144 between the first space 141 and the second space 142, the communication port 144 being higher than the sensing device 143, the sensing device 143 operating under pressure and shutting off the vacuum pump 150 and the valve 160.

[0075] Furthermore, the first space 141 and the second space 142 have a communication port 144. The communication port 144 is positioned higher than the sensing device 143 to prevent the molten metal from entering the second space 142 and to ensure that the vacuum pump 150 can work correctly. The sensing device 143 opens when the molten metal enters the first space 141 and exerts pressure on the sensing device 143. When the sensing device 143 opens, the vacuum pump 150 and the valve 160 are closed to prevent too much molten metal from entering the first space 141 and overflowing into the second space 142, thus keeping the connecting pipe 130 filled with molten metal.

[0076] In one specific embodiment, the base 120 includes, for example, a sealing ring 170, which is disposed around the mating area between the base 120 and the housing 110 and is embedded in the base 120 and / or the housing 110.

[0077] Specifically, after the sealing ring 170 is attached to the base 120 and the housing 110, it ensures the sealing of the inner cavity 112 of the housing and ensures the realization of the negative pressure environment in the inner cavity of the housing 110.

[0078] Preferably, multiple sealing rings 170 can be set. Setting multiple sealing rings 170 can improve the sealing performance of the inner cavity 112 of the housing and ensure the realization of the negative pressure environment in the inner cavity 112 of the housing.

[0079] [Second Embodiment]

[0080] See Figure 7 The second embodiment of the present invention also relates to a casting method using the above-mentioned casting apparatus, specifically including the following steps:

[0081] Step S1: Place solid metal into crucible 121, vacuum pump 150 extracts pressure from inner cavity 112 of the shell, start heating element, and begin metal melting;

[0082] Step S2: Turn on the vacuum pump 150 to pump the molten metal in the crucible 121 into the connecting pipe 130 and the storage pipe 140; the molten metal in the crucible 121 and the molten metal in the connecting pipe 130 flow into the mold 114;

[0083] Step S3: Cooling completes the casting process;

[0084] The housing 110 is fitted with the base 120, and heating elements 280 are evenly distributed in the circumferential direction in the inner cavity 112 of the housing.

[0085] Specifically, the weighed metal raw materials are placed into the crucible 121, and the solid materials to be added during the smelting process are placed into the storage tray 250 on the top of the shell 110. The shell 110 is then lifted and placed on the base 120, and all pipes and gas lines are connected. The mechanical vacuum pump 150 is started to draw the pressure inside the bell jar to the required pressure range for the corresponding metal type. Then, the mechanical vacuum pump 150 is turned off, and the diffusion vacuum pump 150 is started to draw the pressure inside the shell 112 to the required second pressure value P0 for the corresponding metal type. The diffusion vacuum pump 150 is then turned off, the power is turned on, and the heating rod is energized for heating. The temperature is controlled according to the smelting process. When stirring of the melt is required, the first motor 210 on the top of the shell 110 is started, and the ceramic rod 180 is immersed in the melt. The second motor 21 on the top of the shell 110 is then started. 1. The ceramic rod 180 starts rotating to stir the melt. After a period of time, the second motor 211 is turned off to stop stirring. The melt is then allowed to stand and be kept at a certain temperature for a period of time, depending on the type of metal. After the holding period, casting begins. The vacuum pump 150 is turned on to pump the molten metal in the crucible 121 into the connecting pipe 130 and the storage pipe 140. The molten metal in the crucible 121 and the connecting pipe 130 flows into the mold 114. After casting is completed, cooling water is circulated through the cooling layer 111 of the shell 110. When the temperature reading reaches 400°C, nitrogen gas is introduced. The water and nitrogen gas circulation accelerates the solidification of the melt and the cooling of the shell 110. When the temperature reading is between 50-80°C, the shell 110 is lifted, the connecting pipe 130 and the storage pipe 140 are disassembled, and the mold 114 is lifted and flipped in the air. The ingot falls automatically, yielding the finished ingot.

[0086] Furthermore, the liquid storage tube 140 includes: a first space 141, a second space 142 and a sensing device 143, the sensing device 143 being located in the first space 141 near the bottom of the first space 141; the connecting tube 130 includes: a sealing device 131, the sealing device 131 being located near the end of the connecting tube 130 leading to the mold 114.

[0087] Step S1 includes: drawing gas from the inner cavity 112 of the housing to a first pressure value P1 by vacuum pump 150, where P1 = P0;

[0088] Step S2 includes:

[0089] Step S21: Vacuum pump 150 extracts gas from connecting pipe 130 and liquid storage pipe 140 until the pressure value in connecting pipe 130 and liquid storage pipe 140 is less than the first pressure value P1.

[0090] Step S22: The sensing device 143 senses that the metal solution in the first space 141 has submerged the sensing device 143. The sensing device 143 triggers and controls the sealing device 131 to open. The metal solution enters the mold 114 from the crucible 121 through the connecting pipe 130.

[0091] Specifically, the magnitude of the first pressure value P1 is determined by the type of metal. The pressure values ​​in the connecting pipe 130 and the storage pipe 140 are less than the first pressure value P1. The metal solution in the crucible 121 enters the storage pipe 140. The metal solution in the storage pipe 140 submerges the sensing device 143, generating pressure on the sensing device 143. The sensing device 143 triggers and controls the sealing device 131 to open, and the metal solution enters the mold 114 from the crucible 121 through the connecting pipe 130.

[0092] Furthermore, a ceramic rod 180 is provided at the top of the shell 110, and the ceramic rod 180 extends into the crucible 121; step S1 includes:

[0093] Step S11: Place the solid metal into crucible 121;

[0094] Step S12: Connect the housing 110 to the base 120;

[0095] Step S13: Turn on vacuum pump 150 to reduce the pressure in the inner cavity 112 of the housing;

[0096] Step S14: Start the heating element 280 to raise the temperature of the inner cavity 112 of the shell and start metal melting, while rotating the ceramic rod 180.

[0097] Step S15: The inner cavity 112 of the shell is under negative pressure. Under the action of the pressure difference, the air bubbles inside the metal solution continuously escape from the metal solution.

[0098] Step S16: The ceramic rod is removed from the molten metal at 180°, kept warm, and the bubbles inside the molten metal disappear to complete the degassing process and obtain the molten metal.

[0099] Specifically, in step S1, the solid metal is completely melted to obtain a molten metal. The arrangement of the heating elements 280 makes the heating process more stable and reliable. Before melting, the pressure in the inner cavity 112 of the shell is brought up to the first pressure value P1 by the vacuum pump 150. This causes the air bubbles inside the molten metal to continuously escape from the molten metal under the action of the pressure difference. The ceramic rod 180 is rotated to stir the molten metal. After stirring, the ceramic rod 180 is removed from the molten metal. Stirring is beneficial to both metal melting and gas discharge. During the removal process, impurities in the molten metal are also removed, which purifies the molten metal. After the holding time, most of the air bubbles inside the molten metal disappear, thereby preventing defects such as pores from appearing in the ingot after casting, which could cause local stress concentration and become the source of cracks that cause the parts to break.

[0100] Furthermore, the housing 110 is provided with an air inlet pipe 115 for introducing gas into the housing cavity 112 and an exhaust pipe 117 for discharging gas, and the housing 110 is provided with a cooling layer 111 for introducing cooling water.

[0101] Step S3 includes:

[0102] Step S31: Cooling gas is introduced into the housing 110 through the intake pipe 115, and the exhaust pipe 117 is opened;

[0103] Step S32: Cooling water is introduced into the cooling layer 111, and the internal temperature of the shell 110 is waited for to decrease;

[0104] Step S33: Lift the shell 110, then lift the mold 114 and flip it so that the finished product inside the mold 114 can be removed from the mold 114.

[0105] Specifically, cooling gas is introduced into the inner cavity 112 of the shell, the exhaust pipe 117 is opened, and water is simultaneously circulated through the cooling layer 111 of the shell 110 to accelerate the cooling of the inner cavity 112 and improve production efficiency. Once the temperature inside the shell 110 has dropped to a suitable level, the shell 110 is lifted, and then the mold 114 is lifted and flipped to complete the ingot demolding, obtaining the finished ingot. This step improves the stability of the finished ingot.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A casting apparatus, characterized in that, include: Base; A housing is disposed on the base, and an inner cavity is formed between the housing and the base. Heating elements are evenly distributed in the inner cavity along the circumferential direction. The crucible is placed on the base and located inside the shell cavity; A casting mold cavity is formed in the base and communicates with the inner cavity of the shell. The casting mold cavity is located on at least one side of the crucible. A casting mold is disposed within the casting mold cavity, and a casting port is provided between the casting mold and the inner cavity of the shell; The connecting pipe includes a first connecting pipe, a second connecting pipe, and a curved pipe. One end of the first connecting pipe leads to the bottom of the crucible, and the other end of the first connecting pipe is connected to the curved pipe, which overlaps the outer wall of the crucible. One end of the second connecting pipe is connected to the end of the curved pipe away from the first connecting pipe, and the other end of the second connecting pipe leads to the bottom of the mold. The end of the second connecting pipe leading to the mold is provided with a discharge port. A liquid storage tube, one end of which is connected to the second connecting tube; At least one vacuum pump, the vacuum pump being connected to the liquid storage pipe and the inner cavity of the housing; At least one air inlet pipe and at least one air extraction pipe, the air inlet pipe being used to introduce gas into the inner cavity of the housing, and the air extraction pipe being connected to the vacuum pump for extracting pressure from the inner cavity of the housing; The liquid storage tube includes: a first space and a second space; The first space connects to one end of the second connecting pipe near the curved pipe, and the second space connects to the vacuum pump; the connecting pipe includes: A sealing device is located near the end of the second connecting pipe leading to the mold, and is higher than the bottom of the mold cavity; A valve is provided on the air inlet pipe and the air extraction pipe; The liquid storage tube further includes: a sensing device, which is located in the first space near the bottom of the first space; The first space and the second space have a connecting port, which is higher than the sensing device. When the molten metal accumulates in the first space and submerges the sensing device, the sensing device receives a signal and shuts down the vacuum pump and the valve.

2. The casting apparatus according to claim 1, characterized in that, The base includes: A sealing ring is provided around the contact area between the base and the housing, and is embedded in the base and / or the housing.

3. A casting method, implemented by the casting apparatus according to any one of claims 1-2, characterized in that, include: Step S1: Place a solid metal in the crucible, extract the gas from the inner cavity of the shell using the vacuum pump, start the heating element, and begin metal melting to obtain a molten metal. Step S2: Turn on the vacuum pump to draw the molten metal in the crucible into the connecting pipe and the storage pipe; the molten metal in the crucible and the molten metal in the connecting pipe flow into the mold; Step S3: Cooling completes the casting process; The shell is fitted with the base, and heating elements are evenly distributed in the circumferential direction within the shell cavity.

4. The casting method according to claim 3, characterized in that, A ceramic rod is provided at the top of the shell, and the ceramic rod extends into the crucible; step S1 includes: Step S11: Place the solid metal into the crucible; Step S12: Connect the housing to the base; Step S13: Turn on the vacuum pump to reduce the pressure inside the housing cavity; Step S14: Activate the heating element to raise the temperature inside the shell cavity and begin metal melting, while simultaneously rotating the ceramic rod; Step S15: The inner cavity of the shell is under negative pressure, and the air bubbles inside the metal solution continuously escape from the metal solution under the action of the pressure difference; Step S16: The ceramic rod is removed from the metal solution, kept warm, and the bubbles inside the metal solution are allowed to disappear to complete the degassing process and obtain the metal solution.

5. The casting method according to claim 3, characterized in that, The liquid storage tube includes: a first space, a second space, and a sensing device, wherein the sensing device is located in the first space near the bottom of the first space; the connecting tube includes: a sealing device, wherein the sealing device is located near the end of the connecting tube leading to the mold. Step S1 includes: extracting gas from the inner cavity of the housing to a first pressure value P1 using a vacuum pump; Step S2 includes: Step S21: The vacuum pump extracts the gas in the connecting pipe and the liquid storage pipe until the pressure value in the connecting pipe and the liquid storage pipe is less than the first pressure value P1; Step S22: The sensing device detects that the metal solution in the first space has submerged the sensing device. The sensing device triggers and controls the sealing device to open, and the metal solution enters the mold from the crucible through the connecting pipe.

6. The casting method according to claim 3, characterized in that, The housing is provided with an air inlet pipe for introducing gas, an exhaust pipe for discharging gas, and a cooling layer for introducing cooling water. Step S3 includes: Step S31: Introduce cooling gas into the housing through the intake pipe and open the exhaust pipe; Step S32: Cooling water is introduced into the cooling layer, and the temperature inside the shell cavity is allowed to decrease. Step S33: Lift the shell, then lift the mold and flip it over so that the finished product inside the mold can be removed from the mold.

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