A dynamic temperature control method for a casting mold and an impeller casting system

Abstract

The present application relates to the technical field of casting, in particular to a dynamic temperature control method for a casting mold and an impeller casting system. The dynamic temperature control method for the casting mold comprises the following steps: when pouring metal melt based on the forming cavity of the mold, a plurality of forming intervals are sequentially divided from the position where the metal melt first contacts to the position where the metal melt ends to contact, each forming interval has at least one cooling interval; obtaining melt information of the metal melt located in the forming interval; obtaining the temperature difference between the temperature of the metal melt and the temperature of the mold in the forming interval; based on the melt information and the temperature difference, obtaining the heat released by the mold temperature in the forming interval to reach the preset cooling temperature; obtaining medium information of the cooling medium in the cooling interval; based on the heat and the medium information, obtaining the medium flow of the cooling medium to regulate the metal melt temperature in the forming interval. The casting can be real-time temperature field regulated by the mold during the pouring forming process, and the casting quality is improved.

Description

Technical Field

[0001] This invention relates to the field of casting technology, and more specifically, to a dynamic temperature control method for casting molds and an impeller casting system. Background Technology

[0002] Marine propellers, industrial pump impellers, and similar products share similar structural features: a central cylinder surrounded by a uniform matrix of variable-section blades. Figure 11 As shown. Currently, small impeller products typically use weld bead molds, while medium and large impeller products usually use sand molds or metal molds. These products are mostly used in corrosive environments such as seawater and acids / alkalis, and are usually made of corrosion-resistant steel or copper alloys. Due to the solidification characteristics of the materials themselves, sequential solidification needs to be achieved through heat conduction in the mold during the liquid-to-solid forming process to ensure a dense final product. However, because the cross-sectional thickness of these products in the blade area is small, theoretically, the mold needs to have a low cooling rate during liquid metal filling and a high cooling rate during liquid metal solidification to achieve complete forming. Existing traditional molds can only force the sequential solidification temperature field by embedding chills or artificially increasing process compensation allowances. They cannot achieve precise control of mold temperature and dynamic temperature adjustment. The production process is cumbersome, the production efficiency is low, there are many human factors affecting the process, and the material consumption is high, resulting in many product defects, high rework rates, and low product quality stability, which restricts the improvement of product quality and is not suitable for large-scale automated industrial production.

[0003] In order to overcome the shortcomings of the prior art, this invention provides a metal casting mold for matrix blade structures with adjustable cooling speed. This effectively solves the problem of inaccurate temperature control and dynamic temperature adjustment in the casting molds of marine propellers and industrial pump impellers during use, and enables large-scale automated industrial production. Summary of the Invention

[0004] To address the problems of mold deformation caused by excessively high molten metal temperature during casting, the inability to control the temperature field of the molten metal in real time according to the pouring situation, resulting in poor casting density and reduced casting quality, this invention provides a dynamic temperature control method for casting molds and an impeller casting system.

[0005] In a first aspect, the present invention provides a method for dynamic temperature control of casting molds, comprising the following steps:

[0006] When pouring molten metal into the forming cavity of the mold, the forming cavity is divided into n forming intervals from the position where the molten metal first contacts the forming cavity to the position where the pouring ends. n is a natural number and n>1. Each forming interval has at least one cooling interval.

[0007] Obtain melt information of the molten metal located in the forming zone, the melt information including a first specific heat capacity and weight;

[0008] The temperature difference between the molten metal temperature and the mold temperature in the forming zone is obtained;

[0009] Based on the melt information and the temperature difference, the amount of heat required to reach the preset cooling temperature of the mold located in the forming zone is obtained;

[0010] Obtain the medium information of the cooling medium in the cooling zone, the medium information including the second specific heat capacity and density;

[0011] Based on the heat and the medium information, the flow rate of the cooling medium is obtained to regulate the temperature of the molten metal in the forming zone.

[0012] Optionally, obtaining the temperature difference between the molten metal temperature and the mold temperature in the forming zone includes:

[0013] Obtain the pouring temperature and preset cooling temperature of the molten metal in the forming zone;

[0014] Obtain the preset initial temperature and preset target temperature of the mold in the forming zone;

[0015] The temperature difference is ΔT, and the formula for calculating ΔT is:

[0016] ΔT=(T1-T2)+(T3-T4);

[0017] Wherein, T1 is the initial temperature of the molten metal, T2 is the preset cooling temperature of the molten metal, T3 is the preset initial temperature of the mold, T4 is the preset temperature rise of the mold, the preset cooling temperature is ≥ the preset temperature rise, and ΔT is ≥ 0.

[0018] Optionally, the amount of heat required to reach the preset cooling temperature of the molten metal in the forming zone is Q, and the formula for calculating Q is: Q=m·c·ΔT;

[0019] Where m is the weight of the molten metal, c is the first specific heat capacity of the molten metal, and ΔT is the temperature difference.

[0020] Optionally, the flow rate of the cooling medium that regulates the temperature of the molten metal in the forming zone is V, and the formula for calculating V is:

[0021] ;

[0022] Wherein, Q is the heat released required for the mold temperature in the forming zone to reach the preset cooling temperature, Cw is the second specific heat capacity of the cooling medium, ρ is the density of the cooling medium, Δt is the preset temperature rise value of the cooling medium in the cooling zone, where Δt > 0, and K is 1.2-1.5.

[0023] Optionally, based on the pouring temperature of the molten metal, a preset initial temperature of the mold in the forming zone is obtained, wherein 0 < the preset initial temperature of the mold < the initial temperature of the molten metal.

[0024] Optionally, the preset cooling temperatures of the molten metal in the n forming zones may be the same or different.

[0025] Optionally, the preset cooling temperature is determined based on the location of the molten metal in the forming zone or the required solidification time of the molten metal.

[0026] Optionally, based on the location of the molten metal in the forming zone, the preset cooling temperature of the molten metal at different solidification time periods is determined.

[0027] Secondly, the present invention provides an impeller casting system applied to the above-mentioned dynamic temperature control method for casting molds, comprising:

[0028] Module components, opening and closing components, and casting components;

[0029] The module assembly includes m molds, each mold having s cooling channels, where m and s are natural numbers, m > 1, s > 1;

[0030] The opening and closing assembly includes an opening and closing unit and a worktable. The opening and closing unit is arranged around the circumference of the worktable. Each mold is connected to one opening and closing unit. The opening and closing unit drives the mold to move along the worktable surface, so that m molds fit together or separate.

[0031] The casting assembly includes a casting plate and a drive unit connected to the casting plate. The casting plate is provided with a first casting port. The drive unit drives the casting plate to move circumferentially in a first direction or to rise and fall in a second direction. The axis of the first direction is perpendicular to the axis of the second direction.

[0032] The impeller casting system includes a first operating state, which includes:

[0033] When all the sides and bottoms of all adjacent pairs of the m molds are fitted together, the gap between the m molds forms a first forming cavity, which is used for the molten metal to form an impeller. The gap between two adjacent molds forms a second forming cavity, which is used for the molten metal to form the blades of the impeller. The gap between the tops of the m molds forms a second pouring gate, and the gap between the tops of two adjacent molds forms a first riser. The second forming cavity is a part of the first forming cavity, and the second pouring gate and the first riser are connected to the first forming cavity.

[0034] One end face of the casting plate is attached to the top of the m molds, and the first casting port corresponds to the second casting port.

[0035] Optionally, the casting assembly further includes a riser column, and the casting plate is provided with a second riser that cooperates with the riser column, the number of the second riser being the same as the number of the first riser;

[0036] The working state also includes one end of the riser post contacting the top of the mold through the second riser, and the riser post covering part of the first riser.

[0037] Optionally, the worktable is provided with a guide groove, the bottom of the mold is movably connected to the guide groove, and the opening and closing unit drives the mold to reciprocate along the guide groove.

[0038] Optionally, the opening and closing unit includes a fixed base and a telescopic component. The fixed base is connected to the worktable, one end of the telescopic component is connected to the fixed base, and the other end of the telescopic component is connected to the mold.

[0039] Optionally, the drive unit includes a lifting component, a rotating component, and a connecting rod. One end of the lifting component is connected to the worktable, the other end of the lifting component is connected to the rotating component, the rotating component is connected to the connecting rod, and one end of the connecting rod is connected to the casting plate.

[0040] To address the problems of mold deformation due to excessively high molten metal temperature during casting, and the inability to control the temperature field of the molten metal in real time based on the pouring conditions, resulting in poor casting density and reduced casting quality, this invention offers the following advantages:

[0041] This invention reduces internal defects in castings after molten metal forms the final product through precise temperature control and dynamic adjustment in different areas of the mold, thereby improving product quality and dimensional accuracy, and achieving near-net-shape forming. The impeller casting system enables automated mold opening and assembly, enhancing casting production efficiency and product quality stability. Attached Figure Description

[0042] Figure 1 A flowchart of a dynamic temperature control method for casting molds according to one embodiment is shown;

[0043] Figure 2 A top view of the impeller casting system in one embodiment with five molds in the open state is shown.

[0044] Figure 3 It shows Figure 2 A side view of the structure with the five molds in the assembly state;

[0045] Figure 4 It shows Figure 3 A top view diagram;

[0046] Figure 5 It shows Figure 4 A top view of the structure where the central pouring plate fits against the tops of the five molds;

[0047] Figure 6 It shows Figure 5 A schematic diagram of a structure where the intermediate riser column is located in the second riser;

[0048] Figure 7 It shows Figure 3 A schematic diagram of the structure of three mold combinations;

[0049] Figure 8 A side view of the mold structure is shown;

[0050] Figure 9 It shows Figure 8 A structural diagram of the middle mold from another angle;

[0051] Figure 10 It shows Figure 3 Enlarged structural diagram at point A;

[0052] Figure 11 A schematic diagram of the impeller structure is shown.

[0053] Reference numerals: 10-Module assembly; 11-Mold; 12-First forming cavity; 13-Second forming cavity; 14-First riser; 15-Second gating gate; 16-Cooling channel; 161-Inlet; 162-Outlet; 17-Connecting part; 20-Opening and closing assembly; 21-Opening and closing unit; 211-Fixed base; 212-Telescopic component; 22-Workbench; 23-Guide groove; 30-Gating assembly; 31-Gating plate; 32-First gating gate; 33-Second riser; 34-Drive unit; 341-Lifting component; 342-Rotating component; 343-Connecting rod; 35-Riser column; 40-Impeller. Detailed Implementation

[0054] The invention will now be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are described merely to enable those skilled in the art to better understand and thus implement the invention, and are not intended to imply any limitation on the scope of the invention.

[0055] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal", etc., indicate orientations or positional relationships based on the orientations or positional relationships 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 devices, elements, or components to having a specific orientation or being constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientations or positional relationships; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application according to the specific circumstances. In addition, the terms "installed", "set up", "equipped with", "connected", and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, elements, or components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. Furthermore, the terms "first," "second," etc., are mainly used to distinguish different devices, elements, or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.

[0056] Example 1

[0057] This embodiment discloses a method for dynamic temperature control of casting molds, such as... Figure 1 As shown, it includes the following steps:

[0058] When pouring molten metal into the forming cavity of the mold, the forming cavity is divided into n forming sections along the direction from the starting point of pouring to the ending point, where n is a natural number (n > 1). Specifically, if the molten metal falls from the top to the bottom of the forming cavity, it first contacts the bottom until the required pouring volume is reached, at which point pouring ends. The molten metal surface at the end of pouring marks the end of the pouring process. If the molten metal rises from the bottom to the top, the forming cavity is divided into n forming sections along this direction. The forming sections from the bottom to the top are sequentially designated as the first forming section, the second forming section, the third forming section, and so on up to the nth forming section. Each forming section has at least one cooling section, and each cooling section has a corresponding cooling section. The molten metal in the forming zone is cooled. Each forming zone has at least one cooling zone for precise temperature control. When the first forming zone begins to contain molten metal or when the amount of molten metal fills the first forming zone, the cooling zone begins to cool this portion of molten metal. The former or the latter can be selected according to requirements. Preferably, the cooling zone begins to cool this portion of molten metal when the first forming zone begins to contain molten metal. This method allows for real-time temperature control of the molten metal in the first forming zone, providing dynamic temperature control and ensuring the molten metal solidifies sequentially, thus ensuring a dense casting product. When the molten metal fills the first forming zone and reaches the second forming zone, the cooling zone of the second forming zone begins to operate, cooling the molten metal in the second forming zone, and so on.

[0059] The molten metal information located in the forming zone is obtained, including a first specific heat capacity and weight. The molten metal information can be obtained before casting.

[0060] The temperature difference between the molten metal temperature and the mold temperature in the forming zone is obtained. During the casting process, the molten metal temperature in the forming zone is decreasing due to the cooling effect in the cooling zone, while the mold in the forming zone is heated due to the high temperature of the molten metal on its own basis. This state of one cooling and the other heating affects the cooling effect of the molten metal.

[0061] Based on the melt information and the temperature difference, the amount of heat required to reach the preset cooling temperature of the mold in the forming zone is obtained. Based on the melt information and combined with the temperature, the actual amount of heat required to reach the preset cooling temperature of the molten metal in the forming zone is obtained. This means that not only the heat of the molten metal itself is released, but also the heat brought by the temperature difference, so as to ensure the cooling effect when the molten metal is cooled through the cooling zone.

[0062] Obtain the medium information of the cooling medium in the cooling zone, the medium information including the second specific heat capacity and density, and the medium information of the cooling medium can be obtained before casting;

[0063] Based on the heat and the medium information, the medium flow rate of the cooling medium for regulating the temperature of the molten metal in the forming zone is obtained. The actual medium flow rate required for the cooling medium to regulate the temperature of the molten metal can be calculated using the heat to be released by the molten metal and the medium information.

[0064] In this embodiment, since the cooling medium flows within the mold wall and does not directly contact the molten metal, but directly contacts the mold, when the cooling medium cools the molten metal by absorbing heat, it indirectly absorbs heat through the mold to control the temperature of the mold, thus controlling the temperature of the molten metal. Therefore, to reach the preset cooling temperature, cooling requires not only absorbing heat from the molten metal but also absorbing the heat generated by the molten metal on the mold. Thus, when the cooling medium absorbs heat to cool the molten metal, it is necessary to consider the influence of the high-temperature molten metal on the mold temperature, as well as the influence of the mold's own temperature on the molten metal temperature. That is, while the cooling zone cools the mold, the mold itself, influenced by the high-temperature molten metal, also tends to heat up. At this time, the cooling and heating of the mold occur simultaneously, creating a temperature difference. Therefore, by treating the temperature difference as part of the heat released by the molten metal, the accuracy of reaching the preset cooling temperature for the molten metal in the forming zone during the pouring process is ensured.

[0065] This embodiment divides the mold into multiple forming zones, and then sets cooling zones according to the forming zones, ensuring that each forming zone has at least one cooling zone. This allows for better temperature control of the molten metal within the mold. Each of the n forming zones has at least one cooling zone, enabling dynamic temperature field regulation of the mold, resulting in higher temperature control precision and ensuring a denser microstructure of the components.

[0066] In some embodiments, when the first forming zone contains molten metal, the cooling zones of the remaining forming zones determine whether to perform cooling operations or determine the flow rate of the cooling medium based on the mold temperature of the corresponding forming zone. This avoids excessively high mold temperatures in forming zones other than the first forming zone, which could lead to mold deformation or affect the cooling of the molten metal.

[0067] Within the same forming zone, different preset cooling temperatures are determined based on the different amounts of molten metal. Thus, the flow rate of the cooling medium is controlled in real time according to the different preset cooling temperatures to achieve dynamic temperature control.

[0068] Optionally, the cooling medium is cooling water, that is, the medium is water.

[0069] Optionally, the molten metal is copper molten metal.

[0070] Optionally, obtaining the temperature difference between the molten metal temperature and the mold temperature in the forming zone includes:

[0071] Obtain the pouring temperature and preset cooling temperature of the molten metal in the forming zone;

[0072] Obtain the preset initial temperature and preset target temperature of the mold in the forming zone;

[0073] The temperature difference is ΔT, and the formula for calculating ΔT is:

[0074] ΔT=(T1-T2)+(T3-T4);

[0075] Wherein, T1 is the initial temperature of the molten metal, T2 is the preset cooling temperature of the molten metal, T3 is the preset initial temperature of the mold, T4 is the preset temperature rise of the mold, the preset cooling temperature is ≥ the preset temperature rise, and ΔT is ≥ 0.

[0076] Optionally, the amount of heat required to reach the preset cooling temperature of the molten metal in the forming zone is Q, and the formula for calculating Q is: Q=m·c·ΔT;

[0077] Where m is the weight of the molten metal, c is the first specific heat capacity of the molten metal, and ΔT is the temperature difference.

[0078] In this embodiment, the amount of heat Q required for the molten metal in the forming zone to reach the preset cooling temperature can be calculated using the weight of the molten metal injected into the forming zone, the first specific heat capacity of the molten metal, and the temperature difference between the molten metal temperature and the mold temperature in the forming zone. This heat Q formula is applicable to calculating the amount of heat required for the molten metal to release in each forming zone.

[0079] Optionally, the flow rate of the cooling medium that regulates the temperature of the molten metal in the forming zone is V, and the formula for calculating V is:

[0080] ;

[0081] Wherein, Q is the heat released required for the mold temperature in the forming zone to reach the preset cooling temperature, Cw is the second specific heat capacity of the cooling medium, ρ is the density of the cooling medium, Δt is the preset temperature rise value of the cooling medium in the cooling zone, where Δt > 0, and K is 1.2-1.5.

[0082] In this embodiment, 3600 is a constant, and K is a safety factor. The preset temperature rise value is the temperature at which the cooling medium can be allowed to rise within the cooling zone. This preset temperature rise value can be adjusted as needed and is not limited. The medium flow rate V formula in this embodiment is applicable to calculating the medium flow rate of the cooling medium in each cooling zone.

[0083] Optionally, based on the pouring temperature of the molten metal, a preset initial temperature of the mold in the forming zone is obtained, wherein 0 < the preset initial temperature of the mold < the initial temperature of the molten metal.

[0084] In this embodiment, in order to avoid the mold temperature being too high and affecting the subsequent cooling of the molten metal, the preset initial temperature of the mold should be lower than the initial temperature of the molten metal.

[0085] Optionally, the preset cooling temperatures of the molten metal in the n forming zones may be the same or different.

[0086] In this embodiment, since the required cooling or solidification state of the molten metal varies depending on its location within the forming cavity or different forming sections of the mold, the preset cooling temperature can be adjusted as needed. Therefore, the preset cooling temperatures of the molten metal in the n forming sections can be the same or different.

[0087] Optionally, the preset cooling temperature is determined based on the location of the molten metal in the forming zone or the required solidification time of the molten metal.

[0088] In this embodiment, by determining the preset cooling temperature based on the location of the molten metal in the forming zone or the required solidification time of the molten metal, the cooling medium ensures that the temperature control of the molten metal by the mold is dynamic.

[0089] Optionally, based on the location of the molten metal in the forming zone, the preset cooling temperature of the molten metal at different solidification time periods is determined.

[0090] In this embodiment, a preferred method is to adjust the preset cooling temperature of the molten metal according to different solidification time periods.

[0091] Example 2

[0092] This embodiment provides an impeller casting system applied to the dynamic temperature control method for casting molds in Embodiment 1, which may include:

[0093] like Figures 2-4 As shown, there are module component 10, opening and closing component 20, and casting component 30.

[0094] like Figure 2 As shown, the module assembly 10 includes m molds 11. (As...) Figure 9 As shown, each of the molds 11 is provided with s cooling channels 16, where m and s are natural numbers, m > 1, s > 1;

[0095] like Figure 3 and Figure 4 As shown, the opening and closing assembly 20 includes an opening and closing unit 21 and a worktable 22. The opening and closing unit 21 is arranged circumferentially along the worktable 22, and each mold 11 is connected to one opening and closing unit 21. The opening and closing unit 21 drives the mold 11 to move along the surface of the worktable 22, so that m molds 11 can be joined or separated.

[0096] like Figure 2 and Figure 3 As shown, the casting assembly 30 includes a casting plate 31 and a drive unit 34 connected to the casting plate 31. The casting plate 31 is provided with a first casting port 32. The drive unit 34 drives the casting plate 31 to move circumferentially in a first direction or to move up and down in a second direction, wherein the axis of the first direction is perpendicular to the axis of the second direction.

[0097] The impeller casting system includes a first operating state, which includes:

[0098] like Figure 3 and Figure 4 As shown, when the sides and bottoms of all adjacent pairs of the m molds 11 are fitted together, the mold assembly is completed. Figure 7 As shown, the gaps between the m molds 11 form a first forming cavity 12. The first forming cavity 12 houses the molten metal forming impeller 40. Figure 7 As shown, the gap between two adjacent molds 11 forms a second forming cavity 13. The second forming cavity 13 is used by the molten metal to form the blades of the impeller 40. Wherein, as... Figure 3As shown, the gap between the tops of the m molds 11 forms the second pouring gate 15, and the gap between the tops of two adjacent molds 11 forms the first riser 14. The second forming cavity 13 is part of the first forming cavity 12, and the second pouring gate 15 and the first riser 14 are connected to the first forming cavity 12;

[0099] One end face of the casting plate 31 is attached to the top of the m molds 11, and the first casting port 32 corresponds to the second casting port 15.

[0100] Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 The diagram shows the structural state of the impeller casting system from mold opening to mold assembly, and finally to the point where molten metal can be poured and formed.

[0101] Specifically, Figures 2-4 The diagram shows the structural state of m molds 11 in the impeller casting system of this embodiment, from a state where they are far apart to a state where the m molds 11 are combined. Figure 5 The diagram shows the structural state corresponding to the second riser 33 and the first riser 14. Figure 6 The diagram shows the structural state of the impeller casting system after the riser column 35 is assembled, which is used for pouring molten metal.

[0102] Figure 8 and Figure 9 The diagram shows the structure of a single mold 11 with two different viewing angles.

[0103] Specifically, in this embodiment, the impeller casting system operates as follows: m opening and closing units 21 can extend simultaneously or separately, thereby pushing the mold 11 to a preset position, so that the bottoms and sides of the m molds 11 abut and fit together to complete the mold assembly. Figure 3 As shown. The gap formed by the combination of m molds 11 has a sealed structure on the periphery and bottom. The first forming cavity 12 of the gap is as follows. Figure 7As shown. The first forming cavity 12 is used to form molten metal into an impeller 40. The mold 11 is preheated. The drive unit 34 drives the pouring plate 31 to move until the bottom of the pouring plate 31 is in contact with the top of the assembled n molds 11. The first pouring port 32 corresponds to the second pouring port 15. The first pouring port 32 is connected to the first forming cavity 12 through the second pouring port 15. When the molten metal is poured into the first forming cavity 12 through the first pouring port 32 and the second pouring port 15, the cooling medium is simultaneously introduced into the cooling channel 16 to cool the molten metal. When the pouring is completed and the molten metal solidifies into an impeller 40 casting, the drive unit 34 drives the pouring plate 31 to rise and separate from the mold 11. Then the opening and closing unit 21 retracts, causing the mold 11 to move, so that the mold 11 separates from the impeller 40 casting, completing the mold opening and obtaining the impeller 40 casting, as shown. Figure 2 As shown ( Figure 2 Only the diagram showing the state where the n molds 11 are far apart when the opening and closing unit 21 is contracted is shown. The impeller 40 casting structure is as follows: Figure 11 As shown.

[0104] In this embodiment, the impeller casting system is designed to facilitate dynamic temperature control of the mold 11 and the molten metal.

[0105] Optionally, the cooling channel 16 is located in the middle of the cross-section of the mold 11.

[0106] Optionally, such as Figure 9 As shown, n cooling channels 16 are sequentially arranged from the bottom to the top of the mold 11. Along the bottom-to-top direction of the mold 11, adjacent cooling channels 16 may share the same cross-section or different cross-sections. When they share the same cross-section, for example, in two adjacent cooling channels 16, the outlet 162 of the lower cooling channel 16 is located at a higher height than the inlet 161 of the upper cooling channel 16. When they share different cross-sections, for example, in two adjacent cooling channels 16, the outlet 162 of the lower cooling channel 16 is located at a lower height than the inlet 161 of the upper cooling channel 16.

[0107] Optionally, the cooling channels 16 above and below the mold 11 form multiple cooling zones, with at least one cooling channel 16 distributed in each cooling zone along the direction from the bottom to the top of the mold 11. This facilitates dynamic temperature control of the molten metal inside the mold 11.

[0108] Optionally, such as Figure 9As shown, the outlet 162 of the cooling channel 16 is located above the inlet 161 of the cooling channel 16. This allows the cooling medium to flow in the cooling channel 16 in a bottom-in, top-out manner, and the flow direction of the cooling medium is the same as the upward direction of the molten metal in the forming cavity, ensuring that the cooling medium can dynamically control the temperature of the molten metal in real time.

[0109] Optionally, the inlet 161 and outlet 162 of the cooling channel 16 are both located on the side of the mold 11 opposite to the opening and closing unit 21.

[0110] Optionally, such as Figure 3 and Figure 4 As shown, the opening and closing units 21 are arranged at equal intervals along the circumference of the worktable 22.

[0111] Optionally, the opening and closing unit 21 is set with a spacing along the circumference of the worktable 22 according to the spacing between the blades of the impeller 40 to be prepared.

[0112] Optionally, each mold 11 has a connecting part 17 for connecting to the opening and closing unit 21 on the side near the opening and closing unit 21. Specifically, as shown in the figure... Figure 10 As shown, the bottom of the connecting part 17 has a stepped surface structure. This ensures that one part of the bottom of the connecting part 17 contacts the guide groove 23, and the other part contacts the table surface of the worktable 22, thus guaranteeing the reliability of the structure.

[0113] In some embodiments, such as Figures 2-4 As shown, there are 5 molds in mold 11.

[0114] Optionally, such as Figure 6 As shown, the casting assembly 30 also includes a riser column 35. The casting plate 31 is provided with a second riser 33 that mates with the riser column 35. Figure 4 As shown, the number of the second riser 33 is the same as the number of the first riser 14;

[0115] The working state also includes one end of the riser post 35 contacting the top of the mold 11 through the second riser 33, and the riser post 35 covering part of the first riser 14.

[0116] In this embodiment, the bottom of the riser column 35 is a solid structure. In the working state, the first riser 14 corresponds to the second riser 33. The riser column 35 is placed on top of the mold 11 through the second riser 33, so that the riser column 35 can cover part of the first riser 14, while the remaining first riser 14 is covered by the bottom of the pouring pan 31. This allows the molten metal to overflow from the first riser 14 after pouring. Because the molten metal is cooled by a cooling medium, it exhibits sequential solidification; therefore, the molten metal near the first riser 14 solidifies later. At the end of pouring, the riser column 35 covers part of the first riser 14, allowing the riser column 35 to use its own pressure to push the overflowing molten metal back into the first forming cavity. This portion of the molten metal can fill the resulting voids, thus achieving an automatic replenishment effect.

[0117] Optionally, such as Figure 3 As shown and Figure 4 As shown, the second riser 33 is close to the first pouring gate 32. This makes it easier for the riser column 35 to pump the molten metal that overflows from the first riser 14 and is close to the middle of the first forming cavity 12 into the first forming cavity.

[0118] Optionally, the second riser 33 is provided with a riser channel for positioning the riser column 35, and the diameter of the riser channel is adapted to the diameter of the riser column 35.

[0119] Optionally, such as Figure 3 and Figure 10 As shown, the worktable 22 is provided with a guide groove 23. The bottom of the mold 11 is movably connected to the guide groove 23, and the opening and closing unit 21 drives the mold 11 to reciprocate along the guide groove 23.

[0120] In this embodiment, the guide groove 23 facilitates the opening and closing unit 21 to drive the mold 11 to move back and forth within the guide groove 23.

[0121] Optionally, such as Figure 3 As shown, the opening and closing unit 21 includes a fixed base 211 and a telescopic member 212. The fixed base 211 is connected to the worktable 22, one end of the telescopic member 212 is connected to the fixed base 211, and the other end of the telescopic member 212 is connected to the mold 11.

[0122] In this embodiment, the fixed base 211 provides a position fixing function for the telescopic member 212, and the telescopic member 212 drives the mold 11 to reciprocate.

[0123] Optionally, such as Figure 3As shown, the drive unit 34 includes a lifting component 341, a rotating component 342, and a connecting rod 343. One end of the lifting component 341 is connected to the worktable 22, and the other end of the lifting component 341 is connected to the rotating component 342. The rotating component 342 is connected to the connecting rod 343, and one end of the connecting rod 343 is connected to the pouring plate 31.

[0124] In this embodiment, the lifting component 341 drives the pouring plate 31 to move closer to or further away from the top of the mold 11 in the vertical direction, and the rotating component 342 drives the pouring plate 31 to move closer to or further away from the mold 11 in the horizontal direction.

[0125] In some embodiments, the drive unit 34 and the opening / closing unit 21 are driven by hydraulic control.

[0126] Optionally, during the preheating stage, pouring process, solidification process, and mold opening process of the mold 11, a cooling medium is introduced into the cooling channel 16. The cooling medium controls the temperature field of the mold 11 and the molten metal in real time, so that the molten metal is solidified sequentially. This meets the requirement that the mold 11 has a low cooling rate when the liquid metal is filling and a high cooling rate when the liquid metal is solidifying.

[0127] Those skilled in the art will understand that the above embodiments are specific examples of implementing the present invention, and in practical applications, various changes can be made in form and detail without departing from the scope of the present invention.

Claims

1. A method for dynamic temperature control of a casting mold, characterized in that, Includes the following steps: When pouring molten metal into the forming cavity of the mold, the forming cavity is divided into n forming intervals from the position where the molten metal first contacts the forming cavity to the position where the pouring ends. n is a natural number and n>1. Each forming interval has at least one cooling interval. Obtain melt information of the molten metal located in the forming zone, the melt information including a first specific heat capacity and weight; The temperature difference between the molten metal temperature and the mold temperature in the forming zone is obtained; Based on the melt information and the temperature difference, the amount of heat required to reach the preset cooling temperature of the mold located in the forming zone is obtained; Obtain the medium information of the cooling medium in the cooling zone, the medium information including the second specific heat capacity and density; Based on the heat and the medium information, the flow rate of the cooling medium is obtained to regulate the temperature of the molten metal in the forming zone. Obtaining the temperature difference between the molten metal temperature and the mold temperature in the forming zone includes: Obtain the pouring temperature and preset cooling temperature of the molten metal in the forming zone; Obtain the preset initial temperature and preset target temperature of the mold in the forming zone; The temperature difference is ΔT, and the formula for calculating ΔT is: ΔT=(T1-T2)+(T3-T4); Wherein, T1 is the initial temperature of the molten metal, T2 is the preset cooling temperature of the molten metal, T3 is the preset initial temperature of the mold, T4 is the preset temperature rise of the mold, the preset cooling temperature is ≥ the preset temperature rise, and ΔT is ≥ 0. The amount of heat required for the molten metal in the forming zone to reach the preset cooling temperature is Q, and the formula for calculating Q is: Q=m·c·ΔT; Where m is the weight of the molten metal, c is the first specific heat capacity of the molten metal, and ΔT is the temperature difference; The flow rate of the cooling medium that regulates the temperature of the molten metal in the forming zone is V, and the formula for calculating V is: ； Wherein, Q is the heat released required for the mold temperature in the forming zone to reach the preset cooling temperature, Cw is the second specific heat capacity of the cooling medium, ρ is the density of the cooling medium, Δt is the preset temperature rise value of the cooling medium in the cooling zone, where Δt > 0, and K is 1.2-1.

5.

2. The dynamic temperature control method for casting molds according to claim 1, characterized in that, Based on the pouring temperature of the molten metal, the preset initial temperature of the mold in the forming zone is obtained, where 0 < the preset initial temperature of the mold < the initial temperature of the molten metal.

3. The dynamic temperature control method for casting molds according to claim 1, characterized in that, The preset cooling temperatures of the molten metal in the n forming zones may be the same or different.

4. The dynamic temperature control method for casting molds according to claim 1, characterized in that, The preset cooling temperature is determined based on the location of the molten metal in the forming zone or the required solidification time period of the molten metal.

5. The dynamic temperature control method for casting molds according to claim 1, characterized in that, Based on the fact that the molten metal is located in the forming zone, the preset cooling temperature of the molten metal at different solidification time periods is determined respectively.

6. An impeller casting system applied to the dynamic temperature control method for casting molds according to any one of claims 1-5, characterized in that, include: Module components, opening and closing components, and casting components; The module assembly includes m molds, each mold having s cooling channels, where m and s are natural numbers, m > 1, s > 1; The opening and closing assembly includes an opening and closing unit and a worktable. The opening and closing unit is arranged around the circumference of the worktable. Each mold is connected to one opening and closing unit. The opening and closing unit drives the mold to move along the worktable surface, so that m molds fit together or separate. The casting assembly includes a casting plate and a drive unit connected to the casting plate. The casting plate is provided with a first casting port. The drive unit drives the casting plate to move circumferentially in a first direction or to rise and fall in a second direction. The axis of the first direction is perpendicular to the axis of the second direction. The impeller casting system includes a first operating state, which includes: When all the sides and bottoms of all adjacent pairs of the m molds are fitted together, the gap between the m molds forms a first forming cavity, which is used for the molten metal to form an impeller. The gap between two adjacent molds forms a second forming cavity, which is used for the molten metal to form the blades of the impeller. The gap between the tops of the m molds forms a second pouring gate, and the gap between the tops of two adjacent molds forms a first riser. The second forming cavity is a part of the first forming cavity, and the second pouring gate and the first riser are connected to the first forming cavity. One end face of the casting plate is attached to the top of the m molds, and the first casting port corresponds to the second casting port.

7. The impeller casting system according to claim 6, characterized in that, The casting assembly further includes a riser column, and the casting plate is provided with a second riser that cooperates with the riser column, the number of the second riser being the same as the number of the first riser; The working state also includes one end of the riser post contacting the top of the mold through the second riser, and the riser post covering part of the first riser.

8. The impeller casting system according to claim 6, characterized in that, The workbench is provided with a guide groove, the bottom of the mold is movably connected to the guide groove, and the opening and closing unit drives the mold to reciprocate along the guide groove.

9. The impeller casting system according to claim 6, characterized in that, The opening and closing unit includes a fixed base and a telescopic component. The fixed base is connected to the worktable, one end of the telescopic component is connected to the fixed base, and the other end of the telescopic component is connected to the mold.

10. The impeller casting system according to claim 6, characterized in that, The drive unit includes a lifting component, a rotating component, and a connecting rod. One end of the lifting component is connected to the worktable, the other end of the lifting component is connected to the rotating component, the rotating component is connected to the connecting rod, and one end of the connecting rod is connected to the casting plate.

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