A non-traditional large special material smelting and casting mold and a casting method

Abstract

The application belongs to the technical field of metal casting, and particularly relates to a metal casting process for roasting, in particular to a non-traditional large special material smelting and casting mold and a casting method. The device comprises an ingot mold body and a pouring chamber, the ingot mold body is provided with a plurality of independent cooling mechanisms, and the ingot mold body is further provided with a stirring mechanism for removing inclusions; the independent cooling mechanisms are provided with independent flow regulating valves, the stirring mechanism comprises an air inlet pipe, air outlets are formed in the outer wall of the air inlet pipe, a cavity is formed in the bottom of the ingot mold body, the air inlet pipe extends into the cavity, and a plurality of air vents are formed in the bottom of the ingot mold body; the stirring mechanism further comprises a liftable electromagnetic stirring rod which extends into the ingot mold body, and the stirring mechanism further comprises first electric push rods, two first electric push rods are installed on the opposite side walls of the ingot mold body, and the above technical scheme can effectively improve the purity and component uniformity of the formed special material.

Description

Technical Field

[0001] This invention belongs to the field of metal special material casting technology, specifically relating to metal casting processes for roasting, and particularly to a non-traditional large-scale special material smelting and casting mold and casting method. Background Technology

[0002] In the casting process of large special materials, especially in the special steel ingot process, when the weight of the steel ingot is greater than 60 tons, vacuum casting is usually adopted. This process involves large equipment investment, high cost, long production cycle, and the utilization rate of steel ingots is generally less than 70%, with large segregation of steel ingots.

[0003] In related technologies, after steel is smelted, the required molten steel is obtained and then cast. Existing steel ingot casting molds mostly use overall cooling during cooling, which makes it difficult to adjust the cooling rate according to the solidification characteristics of different parts of the steel ingot. This can easily cause uneven solidification of the ingot body and increase the tendency for segregation. At the same time, relying solely on a vacuum environment or argon gas protection during the casting process is insufficient to completely prevent secondary oxidation of the molten steel. Inclusions remaining in the molten steel are also difficult to remove, which can easily affect the internal quality of the final steel ingot and reduce the product qualification rate and performance of large special materials.

[0004] Therefore, there is an urgent need to design a non-traditional large-scale special material smelting and casting mold and casting method to solve the technical problems mentioned above, such as the difficulty in adjusting the cooling rate according to the solidification characteristics of different parts of the steel ingot in the overall cooling process, the increased tendency of segregation, the difficulty in completely avoiding secondary oxidation of molten steel by relying solely on vacuum environment or single argon gas protection during the casting process, and the difficulty in further removing the inclusions remaining in the molten steel, which easily affect the internal quality of the final steel ingot.

[0005] It should be noted that the information disclosed in this background section is only for understanding the background technology of this application concept, and therefore may include information that does not constitute prior art. Summary of the Invention

[0006] This disclosure provides at least one non-traditional large-scale special material smelting and casting mold and casting method.

[0007] In a first aspect, the present disclosure provides a non-traditional large-scale special material smelting and casting mold, an ingot mold body and a casting chamber, wherein the ingot mold body is provided with a plurality of independent cooling mechanisms and a stirring mechanism. Several of the independent cooling mechanisms are equipped with independent flow regulating valves. The stirring mechanism includes an air inlet pipe, an air outlet is provided on the outer wall of the air inlet pipe, a cavity is provided at the bottom of the ingot mold body, the air inlet pipe extends into the cavity, and several ventilation holes are provided at the bottom of the ingot mold body. The stirring mechanism also includes a liftable electromagnetic stirring rod that extends into the mold body.

[0008] In one alternative embodiment, the stirring mechanism further includes a first electric push rod, with two first electric push rods mounted on both sides of the ingot mold body; The telescopic end of the first electric push rod is equipped with a connecting rod, and the end of the connecting rod away from the first electric push rod is equipped with a synchronizing rod; One end of the synchronizing rod is connected to the electromagnetic stirring rod.

[0009] In one optional embodiment, a positioning seat is provided on the outer wall of the mold body, and the connecting rod and the positioning seat are slidably connected.

[0010] In one optional embodiment, the ingot mold body is provided with a plurality of cooling mechanisms, which are arranged sequentially along the height direction. The cooling mechanism includes an inlet and an outlet. A spiral cooling channel is provided on the outer wall of the ingot mold body. The two ends of the spiral cooling channel are connected to the inlet and the outlet, respectively.

[0011] In one optional embodiment, a cover plate is installed on the top of the ingot mold body, a sealing plate is slidably disposed inside the cover plate, and a liquid inlet is provided on the cover plate, the liquid inlet penetrating the sealing plate.

[0012] In one optional embodiment, the cover plate has an arc-shaped opening and a driving mechanism is provided on the cover plate; The driving mechanism includes a second electric push rod, the telescopic end of which has a movable frame. The movable frame is slidably mounted on the cover plate, and a fixed rod is installed on the sealing plate. The fixed rod is slidably connected to the arc-shaped opening.

[0013] In one alternative embodiment, the cover plate has a limiting rod, and the movable frame and the limiting rod are slidably arranged.

[0014] In one alternative embodiment, a hopper is mounted on the cover plate, the narrow opening of the hopper being aligned with the liquid inlet; The inner wall of the hopper has several annular tubes, several nozzles are connected to the annular tubes, and air vents are connected to the annular tubes.

[0015] In one alternative embodiment, the annular tube and the hopper are connected by a fixing block; The direction of the nozzle is parallel to the direction of the inner wall of the hopper; The bottom of the casting chamber is connected to a liquid collection chamber, and a liquid outlet pipe is installed on the liquid collection chamber. The liquid outlet pipe extends into the interior of the hopper, and a filter element is installed inside the liquid outlet pipe. The inner wall of the outlet pipe has two positioning rings, one above the other. The positioning rings are installed on the inner wall of the outlet pipe, and the filter element is located between the two positioning rings. The bottom of the casting chamber is provided with an inclined channel, and the liquid accumulation chamber is located at the bottom of the inclined channel.

[0016] Secondly, this disclosure also provides a casting method applied to the non-traditional large-scale special material smelting and casting molds as described above, specifically including the following steps: Step S1, Smelting Pretreatment 1: The white slag from the ladle refining furnace is held for more than 30 minutes to achieve rapid desulfurization and deoxidation; Step S2, smelting pretreatment two: VD vacuum degree less than 67Pa, holding time greater than 20 minutes, to ensure effective removal of gas and impurities from steel; Step S3, casting: Three-layer argon gas protection casting is adopted. The angles between the argon gas outlet direction and the steel flow direction are 3°, 8° and 15° respectively to form a multi-layer argon gas protection. At the same time, a 24-sided steel ingot mold body is used for casting. The steel ingot riser is formed according to the circular design. The thickness of the insulation plate is increased to improve the utilization rate. Step S4, segmented solidification and controlled cooling: lower section of the ingot body: high flow rate strong cooling to quickly form a solidified outer shell; upper section: low flow rate slow cooling to reduce the temperature difference between the inside and outside.

[0017] The beneficial effects of this invention are as follows: By employing a stirring mechanism, it achieves a synergistic effect of bottom-blowing gas stirring and dynamic electromagnetic stirring. Argon bubbles rising from the bottom of the molten steel drive its flow, promoting the continuous collision and aggregation of dispersed fine non-metallic inclusions. Simultaneously, the adjustable electromagnetic stirring rod stirs the molten steel at different depths, expanding the stirring coverage and enhancing the upward removal of inclusions. This also homogenizes the internal temperature and composition fields of the molten steel, preventing localized component segregation and effectively improving the purity and compositional uniformity of the formed special material, reducing the risk of cracking and uneven performance during subsequent processing. Furthermore, the use of several annular pipes and nozzles for multi-layered argon gas protection during casting reduces secondary oxidation inclusions. Simultaneously, the argon gas ejected from the nozzles flows upwards along the inner wall of the hopper, forming a stable multi-layered argon gas isolation layer around the steel flow, preventing air from contacting the molten steel, and also pre-blowing out residual oxide dust in the hopper, further reducing the possibility of steel contamination. This invention utilizes an independently designed cooling mechanism combined with a segmented controlled cooling process to adjust the cooling water flow rate for different segments of the ingot mold body. This not only enables the rapid formation of a dense solidified shell to prevent mold bulging and steel leakage, but also reduces the temperature gradient between the inside and outside of the ingot body, lowers the probability of thermal stress-induced cracks, and significantly improves the one-time forming qualification rate of large special materials.

[0018] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 A perspective view of a non-traditional large-scale special material smelting and casting mold provided for an embodiment of this disclosure; Figure 2 This is a first structural schematic diagram of a stirring mechanism provided in an embodiment of the present disclosure; Figure 3 This is a schematic diagram of a cooling mechanism provided in an embodiment of the present disclosure; Figure 4 for Figure 3 A magnified view of part A in the middle; Figure 5 This is a schematic diagram of a second structure of a stirring mechanism provided in an embodiment of the present disclosure. Figure 6 for Figure 5 A magnified view of part B in the middle section; Figure 7 This is a schematic diagram of the structure of the hopper provided in an embodiment of this disclosure; Figure 8 This is a schematic diagram of the internal structure of the casting chamber provided in an embodiment of the present disclosure; Figure 9 This is a schematic diagram of the structure of the annular tube provided in an embodiment of this disclosure.

[0022] In the picture: 1. Ingot mold body; 101. Cavity; 2. Casting chamber; 21. Inclined runner; 22. Liquid accumulation chamber; 3. Cooling mechanism; 31. Water inlet; 32. Spiral cooling water channel; 33. Water outlet; 4. Mixing mechanism; 41. Air inlet pipe; 42. Air outlet; 43. Vent hole; 44. First electric push rod; 45. Positioning seat; 46. Connecting rod; 47. Synchronizing rod; 48. Electromagnetic stirring rod; 5. Drive mechanism; 51. Second electric push rod; 52. Moving frame; 53. Limiting rod; 54. Fixing rod; 6. Arc-shaped opening; 7. Hopper; 8. Cover plate; 9. Liquid inlet; 10. Sealing plate; 11. Ring pipe; 12. Nozzle; 13. Fixing block; 14. Filter element; 15. Positioning ring; 16. Vent pipe; 17. Liquid outlet pipe. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure 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.

[0024] Research has revealed that in related technologies, steel ingot casting molds often employ overall cooling during the cooling process. This makes it difficult to adjust the cooling rate according to the solidification characteristics of different parts of the steel ingot, which can easily lead to uneven solidification of the ingot body and increase the tendency for segregation. At the same time, relying solely on a vacuum environment or argon gas protection during the casting process cannot completely prevent secondary oxidation of the molten steel. Furthermore, it is difficult to further remove the inclusions remaining in the molten steel, which can easily affect the internal quality of the final steel ingot and reduce the product qualification rate and performance of large special materials.

[0025] The shortcomings of the above solutions are the result of the inventor's practical experience and careful research. Therefore, the discovery process of the above problems and the solutions proposed in this disclosure below should be considered as the inventor's contribution to this disclosure.

[0026] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the embodiments and features described below can be combined with each other. Furthermore, in the accompanying drawings, the thickness of components may be exaggerated or reduced for the purpose of effectively describing the technical content.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] Based on the above research, and referring to Figures 1-4This disclosure provides a non-traditional large-scale special material smelting and casting mold, including an ingot mold body 1 and a casting chamber 2. The ingot mold body 1 is equipped with several independent cooling mechanisms 3 and a stirring mechanism 4 for removing inclusions. Each of the independent cooling mechanisms 3 is equipped with an independent flow regulating valve. The stirring mechanism 4 includes an air inlet pipe 41 with an air outlet 42 on its outer wall. A cavity 101 is formed at the bottom of the ingot mold body 1, and the air inlet pipe 41 extends into the cavity 101. Several ventilation holes 43 are also formed at the bottom of the ingot mold body 1. The stirring mechanism 4 further includes a liftable electromagnetic stirring rod 48 that extends into the ingot mold body 1. The ingot mold body 1 is made of 24-sided steel.

[0029] In at least one embodiment, a 24-sided ingot mold is used for casting, optimizing the solidification process and improving internal quality: it provides a more uniform and gentler radial heat flow, which helps reduce thermal stress and cracking tendency caused by uneven cooling. Uniform cooling helps form wider equiaxed grain zones, reduces the proportion of columnar grains, thereby improving central segregation and porosity, and enhancing the uniformity of the ingot's internal structure.

[0030] In at least one embodiment, several independent cooling mechanisms 3 are equipped with independent flow regulating valves, which can realize slow cooling at the top and strong cooling at the bottom gradient solidification, so that the solidification sequence inside the steel ingot gradually advances from the bottom to the top, effectively reducing common casting defects such as central shrinkage cavities and porosity, and improving the overall density and homogeneity of the steel ingot. Reference Figure 4 In at least one embodiment, the stirring mechanism 4 adopts a combination of bottom-blowing gas stirring and liftable electromagnetic stirring. During the bottom-blowing gas process, argon gas is sent into the cavity 101 through the air outlet 42 via the air inlet pipe 41, and then evenly enters the molten steel through several vent holes 43 at the bottom of the ingot mold body 1. As the bubbles rise, they can drive the molten steel to flow, gradually bringing the non-metallic inclusions in the molten steel to the surface slag area. With the help of the liftable electromagnetic stirring rod 48, the molten steel is electromagnetically stirred at different heights, which further enhances the aggregation and floating effect of inclusions, reduces the content of non-metallic inclusions inside the steel ingot, and improves the purity of the special material.

[0031] Reference Figure 5 and Figure 6In at least one embodiment, during actual casting operations, the entire device is first assembled, and the status of the flow regulating valves of each independent cooling mechanism 3 and the flexibility and airtightness of the stirring mechanism 4 are checked. Then, the top of the ingot mold body 1 is sealed, and the molten special steel is injected into the ingot mold body 1 through the hopper 7. During the injection process, the vent pipe 16 delivers inert protective gas into the annular pipe 11. The gas is sprayed out through several nozzles 12 set on the inner wall of the parallel hopper 7, forming a protective air curtain flowing along the inner wall inside the hopper 7, effectively blocking air from entering the molten steel, avoiding secondary oxidation during the injection process, and ensuring the stability of the molten steel composition. After the injection is completed, the second electric push rod 51 is activated to push the moving frame 52 to slide along the limiting rod 53. During the sliding process, the moving frame 52, through the cooperation of the arc-shaped opening 6 and the fixed rod 54, drives the sealing plate 10 to slide inside the cover plate 8, sealing the liquid inlet 9 and ensuring a closed casting environment inside the ingot mold body 1.

[0032] Reference Figure 2 and Figure 3 In at least one embodiment, after the liquid injection and sealing are completed, the water inlet of the bottom cooling mechanism 3 is turned on. According to the preset cooling process, the cooling water flow rate of the bottom independent cooling mechanism 3 is increased and the cooling water flow rate of the upper cooling mechanism 3 is reduced to achieve gradient cooling. At the same time, the stirring mechanism 4 is turned on, and the air inlet pipe 41 continuously delivers argon gas into the cavity 101. The argon gas is evenly blown into the bottom of the molten steel through the vent hole 43. At the same time, the first electric push rod 44 reciprocates, and drives the electromagnetic stirring rod 48 to reciprocate in the vertical direction in the molten steel through the connecting rod 46 and the synchronous rod 47, thereby turning on the electromagnetic stirring function to dynamically stir the molten steel at different depths, further promoting the floating of inclusions, and at the same time uniformizing the internal temperature field of the molten steel and improving the uniformity of composition. The inclusions in the overflow molten steel are intercepted by the filter element 14 in the liquid outlet pipe 17. The filtered purified molten steel flows back to the hopper 7 through the liquid outlet pipe 17 to participate in casting again, reducing the waste of molten steel and avoiding the impact of slag residue on the quality of steel ingots. After the molten steel has gradually solidified from bottom to top, turn off the stirring mechanism 4 and the cooling water supply. After the steel ingot has completely cooled down, open the ingot mold body 1 and take out the formed steel ingot to complete the entire casting process.

[0033] Reference Figures 1-4In at least one embodiment, the stirring mechanism 4 further includes a first electric push rod 44. Two first electric push rods 44 are installed on both sides of the ingot mold body 1. A connecting rod 46 is installed on the telescopic end of the first electric push rod 44. A synchronizing rod 47 is installed on the end of the connecting rod 46 away from the first electric push rod 44. One end of the synchronizing rod 47 is connected to the electromagnetic stirring rod 48. In specific implementation: the working process of the stirring mechanism 4 is as follows: the first electric push rod 44 drives the connecting rod 46 to slide stably along the positioning seat 45 through the reciprocating motion of the telescopic end. Then, the electromagnetic stirring rod 48 is driven to rise and fall steadily in the vertical direction inside the ingot mold body 1 through the synchronizing rod 47. Without the need for manual adjustment of the stirring position, dynamic stirring of molten steel at different depths can be achieved, ensuring uniform stirring coverage and improving the effect of floating and discharging inclusions. At the same time, the rising and falling process is synchronous and stable, and will not disturb the solidification trend of the molten steel inside the ingot mold body.

[0034] Reference Figure 2 In at least one embodiment, a positioning seat 45 is provided on the outer wall of the ingot mold body 1, and the connecting rod 46 is slidably connected to the positioning seat 45. Specifically, the positioning seat 45 is used to limit the movement of the connecting rod 46, ensuring the stability of its trajectory.

[0035] Reference Figure 3 In at least one embodiment, a cooling mechanism 3 is provided on the ingot mold body 1, and several cooling mechanisms 3 are arranged sequentially along the height direction. Each cooling mechanism 3 includes an inlet 31 and an outlet 33. A spiral cooling water channel 32 is formed on the outer wall of the ingot mold body 1, with both ends of the spiral cooling water channel 32 connected to the inlet 31 and the outlet 33, respectively. Specifically, the several cooling mechanisms 3 enable gradient cooling. By introducing cooling water into the spiral cooling water channel 32, the outer wall of the ingot mold body 1 is uniformly cooled. The cooling water flow rate of different cooling mechanisms 3 can be controlled by independent flow regulating valves. Combined with a preset gradient cooling process, the molten steel gradually solidifies from the bottom to the top of the ingot mold body, guiding shrinkage defects to the riser area at the top of the ingot, effectively improving the casting quality of the ingot body.

[0036] Reference Figure 7 In at least one embodiment, a cover plate 8 is installed on the top of the ingot mold body 1, and a sealing plate 10 is slidably connected inside the cover plate 8. A liquid inlet 9 is provided on the cover plate 8, and the liquid inlet 9 penetrates the sealing plate 10. Specifically, the sealing plate 10 is used for sealing during the cooling and solidification process, preventing gas from entering the mold cavity and avoiding splashing of molten steel from the liquid inlet 9 during casting, thus improving the safety of the operation. After the liquid injection is completed, the liquid inlet 9 can be sealed by sliding the sealing plate 10. This operation is convenient, requires no additional sealing components, and simplifies the overall structure of the device.

[0037] Reference Figure 6 In at least one embodiment, the cover plate 8 has an arc-shaped opening 6, and the cover plate 8 is provided with a driving mechanism 5 for sealing the cover plate 8. The driving mechanism 5 includes a second electric push rod 51, and the telescopic end of the second electric push rod 51 has a movable frame 52. The movable frame 52 is slidably connected to the cover plate 8. A fixing rod 54 is installed on the sealing plate 10, and the fixing rod 54 is slidably connected inside the arc-shaped opening 6. In a specific implementation: the driving mechanism 5 is used to drive the sealing plate 10 to rotate. During pouring, the sealing plate 10 is opened and molten steel is poured into the ingot mold body 1 through the liquid inlet 9. At this time, argon gas is continuously supplied into the ingot mold body 1 through the annular pipe 11, thereby venting the air in the ingot mold body 1 through the liquid inlet 9. After pouring is completed, the sealing plate 10 is covered to cover the liquid inlet 9, thereby completing the sealing.

[0038] Reference Figure 6 In at least one embodiment, the cover plate 8 has a limiting rod 53, and the movable frame 52 and the limiting rod 53 are slidably connected. Specifically, the limiting rod 53 is used to limit the movement of the movable frame 52, ensuring the stability of its movement.

[0039] Reference Figure 8 and Figure 9 In at least one embodiment, a hopper 7 is installed on the cover plate 8, the hopper 7 is located directly above the liquid inlet 9, and the inner wall of the hopper 7 has several annular pipes 11, with several nozzles 12 connected to the annular pipes 11, and vent pipes 16 connected to the annular pipes 11. In specific implementation: the several nozzles 12 spray argon gas directionally along the inner wall of the hopper 7, forming a continuous and close-fitting gas film protective layer inside the hopper 7. On the one hand, this can prevent outside air from contacting the falling molten steel, avoiding secondary oxidation of the molten steel during the injection process, and ensuring that the purity of the special steel composition meets the casting requirements; on the other hand, the sprayed argon gas flow can also purge the air in the hopper 7 in advance, reducing the amount of gas brought into the ingot mold body during the injection process, and reducing the risk of porosity defects inside the steel ingot.

[0040] Reference Figure 9 In at least one embodiment, the annular tube 11 and the hopper 7 are connected by a fixing block 13, and the direction of the nozzle 12 is parallel to the direction of the inner wall of the hopper 7.

[0041] Reference Figure 9In at least one embodiment, the bottom of the casting chamber 2 is fixedly connected to a liquid accumulation chamber 22, and a liquid outlet pipe 17 is installed on the liquid accumulation chamber 22. The liquid outlet pipe 17 extends into the interior of the hopper 7, and a filter element 14 is installed inside the liquid outlet pipe 17. The inner wall of the liquid outlet pipe 17 has two positioning rings 15, which are installed on the inner wall of the liquid outlet pipe 17, and the filter element 14 is located between the two positioning rings 15. An inclined channel 21 is provided at the bottom of the casting chamber 2, and the liquid accumulation chamber 22 is located at the bottom of the inclined channel 21. In practice: the filter element 14 is used to filter inclusions in the molten steel during casting. The overflowing molten steel flows along the inclined channel 21 into the accumulation chamber 22, and then back into the hopper 7 via the outlet pipe 17. Scum and large inclusions in the molten steel are intercepted and retained by the filter element 14. The filtered pure molten steel is then reused in the casting process. Two positioning rings 15 stabilize and fix the filter element 14, preventing displacement and shaking during the molten steel flow, thus ensuring stable filtration. This structure reduces molten steel waste and lowers production costs. It also prevents scum and inclusions from re-entering the ingot mold with the returned molten steel, ensuring the purity and internal quality of the ingot. Furthermore, the filter element 14 is easy to replace and facilitates regular maintenance and cleaning.

[0042] This invention also includes a casting method applied to the non-traditional large-scale special material smelting and casting molds as described above, specifically comprising the following steps: S1: Smelting pretreatment 1: The white slag in the ladle refining furnace is kept for more than 30 minutes to achieve rapid desulfurization and deoxidation; S2: Smelting Pretreatment 2: VD (Vacuum Degassing) Vacuum degree less than 67Pa, holding time greater than 20 minutes, to ensure effective removal of gases and impurities from steel; S3: Casting: Three-layer argon protection casting is adopted. The angles between the argon gas outlet direction and the steel flow direction are 3°, 8° and 15° respectively to form a multi-layer argon gas protection. At the same time, a 24-sided steel ingot mold body is used for casting. The steel ingot riser is formed in a circular design. The thickness of the insulation plate is increased to improve the utilization rate. S4: Segmented solidification and controlled cooling: Lower section of the ingot body: high flow rate strong cooling to quickly form a solidified outer shell; upper section: low flow rate slow cooling to reduce the temperature difference between the inside and outside.

[0043] This method adds a VCD (vacuum carbon deoxidation) process and adopts a "VCD+VD" dual vacuum combination: it avoids the generation of non-deformable inclusions such as high melting point Al2O3 and SiO2 from the source, and the molten steel is "naturally clean", achieving the same level or even better purity of molten steel as vacuum casting.

[0044] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, several units or components may be combined or integrated into another system, or some features may be ignored or not executed. Based on the above-described ideal embodiments of the present invention, and through the above description, those skilled in the art can make various changes and modifications without departing from the technical spirit of the disclosed embodiments. The technical scope of the embodiments of this disclosure is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A non-traditional large-scale special material smelting and casting mold, comprising an ingot mold body (1) and a casting chamber (2), characterized in that, The ingot mold body (1) is provided with several independent cooling mechanisms (3), and the ingot mold body (1) is also provided with a stirring mechanism (4). Several independent cooling mechanisms (3) are provided with independent flow regulating valves. The stirring mechanism (4) includes an air inlet pipe (41). An air outlet (42) is provided on the outer wall of the air inlet pipe (41). A cavity (101) is provided at the bottom of the ingot mold body (1). The air inlet pipe (41) extends into the cavity (101). Several ventilation holes (43) are provided at the bottom of the ingot mold body (1). The stirring mechanism (4) also includes a liftable electromagnetic stirring rod (48) that extends into the mold body (1).

2. The non-traditional large-scale special material smelting and casting mold as described in claim 1, characterized in that, The stirring mechanism (4) also includes a first electric push rod (44), and two first electric push rods (44) are installed on both sides of the ingot mold body (1); A connecting rod (46) is installed at the telescopic end of the first electric push rod (44), and a synchronizing rod (47) is installed at the end of the connecting rod (46) away from the first electric push rod (44). One end of the synchronizing rod (47) is connected to the electromagnetic stirring rod (48).

3. The non-traditional large-scale special material smelting and casting mold as described in claim 2, characterized in that, The outer wall of the mold body (1) is provided with a positioning seat (45), and the connecting rod (46) and the positioning seat (45) are slidably connected.

4. The non-traditional large-scale special material smelting and casting mold as described in claim 1, characterized in that, The ingot mold body (1) is provided with a plurality of cooling mechanisms (3), and the plurality of cooling mechanisms (3) are arranged sequentially along the height direction; The cooling mechanism (3) includes an inlet (31) and an outlet (33). A spiral cooling channel (32) is provided on the outer wall of the mold body (1). The two ends of the spiral cooling channel (32) are connected to the inlet (31) and the outlet (33) respectively.

5. The non-traditional large-scale special material smelting and casting mold as described in claim 1, characterized in that, The top of the mold body (1) is equipped with a cover plate (8), and a sealing plate (10) is slidably arranged inside the cover plate (8). A liquid inlet (9) is opened on the cover plate (8), and the liquid inlet (9) penetrates the sealing plate (10).

6. The non-traditional large-scale special material smelting and casting mold as described in claim 5, characterized in that, An arc-shaped opening (6) is provided on the cover plate (8), and a driving mechanism (5) is provided on the cover plate (8). The drive mechanism (5) includes a second electric push rod (51), and a movable frame (52) is provided on the telescopic end of the second electric push rod (51). The movable frame (52) is slidably disposed on the cover plate (8). A fixing rod (54) is installed on the sealing plate (10), and the fixing rod (54) is slidably connected in the arc-shaped opening (6).

7. The non-traditional large-scale special material smelting and casting mold as described in claim 5, characterized in that, The cover plate (8) has a limiting rod (53), and the moving frame (52) and the limiting rod (53) are slidably arranged.

8. The non-traditional large-scale special material smelting and casting mold as described in claim 5, characterized in that, A hopper (7) is installed on the cover plate (8), and the narrow opening of the hopper (7) is aligned with the liquid inlet (9); The inner wall of the hopper (7) has several annular tubes (11), several nozzles (12) are connected to the annular tubes (11), and air pipes (16) are connected to the annular tubes (11).

9. The non-traditional large-scale special material smelting and casting mold as described in claim 8, characterized in that, The annular pipe (11) and the hopper (7) are connected by a fixing block (13); The direction of the nozzle (12) is parallel to the direction of the inner wall of the hopper (7); The bottom of the casting chamber (2) is connected to the liquid collection chamber (22), and the liquid collection chamber (22) is equipped with a liquid outlet pipe (17). The liquid outlet pipe (17) extends into the interior of the hopper (7), and a filter element (14) is installed inside the liquid outlet pipe (17). The inner wall of the outlet pipe (17) has two positioning rings (15), which are installed on the inner wall of the outlet pipe (17) and the filter element (14) is located between the two positioning rings (15). The bottom of the casting chamber (2) is provided with an inclined channel (21), and the liquid accumulation chamber (22) is located at the bottom of the inclined channel (21).

10. A casting method, characterized in that, The application of non-traditional large-scale special material smelting and casting molds as described in any one of claims 1-9 specifically includes the following steps: Step S1, Smelting Pretreatment 1: The white slag from the ladle refining furnace is held for more than 30 minutes to achieve rapid desulfurization and deoxidation; Step S2, smelting pretreatment two: VD vacuum degree less than 67Pa, holding time greater than 20 minutes, to ensure effective removal of gas and impurities from steel; Step S3, casting: Three-layer argon gas protection casting is adopted. The angles between the argon gas outlet direction and the steel flow direction are 3°, 8° and 15° respectively to form a multi-layer argon gas protection. At the same time, a 24-sided steel ingot mold body is used for casting. The steel ingot riser is formed according to the circular design. The thickness of the insulation plate is increased to improve the utilization rate. Step S4, segmented solidification and controlled cooling: lower section of the ingot body: high flow rate strong cooling to quickly form a solidified outer shell; upper section: low flow rate slow cooling to reduce the temperature difference between the inside and outside.

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