Nuclear power sealing tile casting mold and production process

Abstract

The invention discloses a nuclear power sealing tile casting mold, and belongs to the technical field of centrifugal casting, the nuclear power sealing tile casting mold comprises a transmission plate, an outer mold, a mold cushion, a bushing, a mold cover, a sliding rail, a feeding assembly, a ventilation assembly and a cooling assembly, the transmission plate is fixedly mounted at the output end of a centrifugal machine, and the outer mold is fixedly mounted at the outer end of the transmission plate; a die cushion, a lining and a die cover are sequentially assembled in the outer die, the feeding assembly and the ventilation assembly are movably assembled on the sliding rail, the discharging end of the feeding assembly is located in the lining, the ventilation end of the ventilation assembly is located in the middle of the outer side of the outer end face of the die cover, and the two cooling assemblies are symmetrically and fixedly installed on the sliding rail. Through the design of the mold and the arrangement of the feeding assembly, the ventilation assembly and the cooling assembly, uniform pouring of molten metal can be guaranteed, internal and external synchronous cooling and precise temperature control of a casting are achieved, the defects such as segregation and shrinkage porosity of the casting are effectively reduced, and the qualification rate of the casting is increased.

Description

Technical Field

[0001] The invention belongs to the technical field of centrifugal casting, and in particular provides a nuclear power sealing tile casting mold and a production process. Background Art

[0002] The seals used in nuclear power plants are crucial sealing components in nuclear reactors, playing a crucial role in ensuring the safe operation of nuclear reactors. The performance of these seals not only affects the safety of the nuclear power plant, but also has a direct impact on the economic benefits of the entire plant.

[0003] To ensure the quality of sealing tiles for nuclear power plants, castings must meet PT level 3 testing standards and pass UT testing. Regarding composition, sealing tiles must contain between 14% and 16% tin (Sn) and 84% and 86% copper (Cu). Furthermore, the lead (Pb) impurity content must be less than 0.1%, and the sum of all other impurities must not exceed 0.3%. During the casting production process, defects that significantly impact quality, such as pores, slag holes, linear defects, segregation, inclusions, and coarse columnar crystals, must be strictly avoided. Linear defects, due to their potential harmfulness, require special attention and must be ensured to be absent.

[0004] However, in the existing casting process, defects are prone to occur in the inner diameter, which indicates that the defects are located in the last solidification area of ​​the casting, and these areas are usually accompanied by traces similar to segregation. The reasons for the segregation are analyzed as follows: 1. Due to the uneven distribution of the temperature field, the cooling rates of different parts of the casting are different (the outer layer cools quickly and the center cools slowly), causing the solute to gather in the last solidified area, thus forming macro segregation; 2. In terms of elemental properties, low melting point elements (such as Sn) tend to be enriched at grain boundaries or the last solidification area; 3. Under the action of the centrifugal field, density difference becomes the dominant factor in solute distribution: high-density components (such as copper Cu, with a density of 8.96 g / cm³) tend to migrate outward, while low-density components (such as tin Sn, with a density of 7.3 g / cm³) are enriched inward, thus forming macro-segregation.

[0005] Therefore, in order to solve the above problems, a nuclear power sealing tile casting mold and production process are proposed. Summary of the Invention

[0006] In order to solve the above problems, the present invention provides a nuclear power sealing tile casting mold and production process.

[0007] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a nuclear power sealing tile casting mold, including a transmission plate, an outer mold, a mold pad, a bushing, a mold cover, a slide rail, a feed assembly, a ventilation assembly and a cooling assembly. The transmission plate is fixedly installed on the output end of the centrifuge, and the outer mold is fixedly installed on the outer end of the transmission plate. The outer mold is sequentially equipped with a mold pad, a bushing and a mold cover. The feed assembly and the ventilation assembly are both movably assembled on the slide rail. The discharge end of the feed assembly is located in the bushing, and the ventilation end of the ventilation assembly is located in the middle of the outer side of the outer end surface of the mold cover. The two cooling assemblies are symmetrically fixed on the slide rail, and the cooling assembly is used to cool the outer mold.

[0008] Furthermore, a connecting plate is fixedly installed on the inner end of the transmission plate, and the connecting plate is fixedly installed on the output end of the motor. A cylindrical groove and an air inlet hole connected to the cylindrical groove are provided on the outer end surface of the connecting plate. Through holes are provided in the middle of the transmission plate, mold pad and mold cover, and the ventilation end of the ventilation assembly corresponds to the through hole.

[0009] Furthermore, a slideway is provided on the upper surface of the slide rail, support plates are fixedly installed on both sides of the slide rail, auxiliary wheels are fixedly installed on the upper surface of the support plate, and the auxiliary wheels are used to support and position the transmission plate and the outer mold.

[0010] Furthermore, the cooling assembly includes a cooling support frame, a cooling connecting plate, a cooling plate and a water pipe. The cooling support frame is fixedly installed on the support plate, the cooling connecting plate is fixedly installed on the upper end of the cooling support frame, the cooling plate is fixedly installed on the inner side of the upper end of the cooling connecting plate, the outer wall of the water pipe is evenly fixedly installed with branch pipes, the outer end of the branch pipe is fixedly installed with an atomizing nozzle, the atomizing nozzle is fixedly installed on the outer wall of the cooling plate, and the liquid outlet end of the atomizing nozzle passes through the cooling plate and faces the outer mold, and an electromagnetic valve is installed between the atomizing nozzle and the water pipe.

[0011] Furthermore, the feed assembly includes a feed support frame and a feed pipe, and the feed support frame is movably assembled on a slide rail, and a side slit water outlet is provided on the side wall of the discharge end of the feed pipe.

[0012] Furthermore, the feed end and the discharge end of the feed pipe are both arranged horizontally, and the middle section of the feed pipe is a downward curved pipe. The diameter of the feed end of the feed pipe is larger than the diameter of the discharge end, and a spiral plate is fixedly installed inside the middle section of the feed pipe.

[0013] Furthermore, the side slit water inlet is opened at an angle, and the position of one side of the side slit water inlet facing the feeding end of the feeding pipe is higher than the other side.

[0014] Furthermore, the ventilation assembly includes a ventilation support frame, an air pump, a support pipe and a drainage ring. The ventilation support frame is movably assembled on a slide rail, and the ventilation support frame is located between the outer mold and the feeding support frame. The air pump is fixedly installed on the upper end of the ventilation support frame. The support pipe is fixedly installed on the air pump, and the drainage ring is fixedly installed on the upper end of the support pipe. The drainage ring is sleeved on the feeding pipe.

[0015] Furthermore, the drainage ring is composed of an outer metal ring, an intermediate metal ring, and an inner metal ring, the two ends of the outer metal ring are respectively connected to the intermediate metal ring and the inner metal ring, an annular cavity is formed between the outer metal ring and the intermediate metal ring, an air outlet cavity is formed between the intermediate metal ring and the inner metal ring, and the annular cavity is connected to the air outlet cavity, and the outlet of the air outlet cavity is far away from the outer mold.

[0016] A production process for nuclear power sealing tiles, using the above-mentioned nuclear power sealing tile casting mold, specifically comprises the following steps: Step 1: Install the mold at the output end of the centrifuge and complete the settings of the feeding assembly, ventilation assembly, and cooling assembly; Step 2: Preheat the mold by using a gas or electric heating device to preheat the bushing in the mold to 180-300°C, and then evenly spray the heat-resistant coating on the inner wall of the mold pad, bushing, and mold cover; Step 3: Centrifugal pouring: Start the centrifuge and inject the molten metal into the mold through the feeding assembly. The synergistic effect of the side slit water inlet and centrifugal force makes the molten metal evenly formed. The ventilation assembly is started simultaneously to assist in heat dissipation on the inner surface of the casting. Step 4: Centrifugal solidification. After pouring is completed, the centrifuge and ventilation components continue to work, and the cooling component is started at the same time. Through ventilation and heat dissipation on the inside of the casting and spray cooling on the outside of the mold, internal and external coordinated cooling is achieved, which reduces the solidification time of the molten metal, inhibits the flow of liquid phase between dendrites, and reduces segregation. Step 5: Casting removal and post-processing: After the casting cools to a certain temperature below the solidus line, stop the centrifuge and take out the casting. Then, clean the casting and perform non-destructive testing.

[0017] The beneficial effects of using the present invention are: 1. The design of the mold, as well as the arrangement of the feeding assembly, ventilation assembly, and cooling assembly of the present invention can ensure uniform pouring of the molten metal, and realize synchronous cooling and precise temperature control of the inside and outside of the casting, effectively reducing the occurrence of defects such as segregation and shrinkage of the casting, and improving the qualified rate of the casting.

[0018] 2. The present invention designs a feed component. By designing the shape of the feed pipe, the flow rate of the molten metal can be increased, the speed of the molten metal can be closer to the rotation speed of the mold, and the stability of the casting process is improved. A spiral plate is arranged in the feed pipe to guide the flow direction of the molten metal, so that the molten metal flows out more smoothly. At the same time, the design of the side slit water outlet can make the molten metal flow out evenly along the side slit water outlet, and spread smoothly in the bushing in a curtain shape, significantly reducing turbulence and splashing.

[0019] 3. The ventilation assembly designed in the present invention can generate uniform axial airflow, promote air circulation inside the casting, improve the cooling efficiency inside the casting, eliminate the temperature gradient of the casting, and reduce the segregation phenomenon of the casting. At the same time, the airflow generated can also assist in cooling the molten metal in the feed pipe, making it easier to adjust the pouring temperature.

[0020] 4. The present invention is designed with a cooling device, which sprays and cools the outer mold through the atomizing nozzle on the cooling plate. At the same time, based on the temperature feedback of the temperature measuring device and the control of the solenoid valve, the spraying degree can be adjusted according to the different casting stages, and local overheating can be avoided, thereby achieving more effective and stable cooling work. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is one of the three-dimensional schematic diagrams of the present invention.

[0022] Figure 2 This is the second stereoscopic schematic diagram of the present invention.

[0023] Figure 3 It is a front sectional view of the present invention.

[0024] Figure 4 It is a three-dimensional schematic diagram of the connecting plate of the present invention.

[0025] Figure 5 It is a three-dimensional schematic diagram of the feeding assembly of the present invention.

[0026] Figure 6 It is a three-dimensional schematic diagram of the ventilation component of the present invention.

[0027] Figure 7 For the present invention Figure 3 A partial enlarged view of part a.

[0028] Figure 8 It is a three-dimensional schematic diagram of the cooling assembly of the present invention.

[0029] Figure 9 For the present invention Figure 8 A partial enlarged view of part b.

[0030] The accompanying drawings include: 1. transmission plate, 11. connecting plate, 12. cylindrical groove, 13. air inlet, 2. outer mold, 3. mold pad, 4. bushing, 5. mold cover, 6. slide rail, 61. support plate, 62. auxiliary wheel, 7. feeding assembly, 71. feeding support frame, 72. feeding pipe, 73. spiral plate, 74. side slit water inlet, 8. ventilation assembly, 81. ventilation support frame, 82. air pump, 83. support pipe, 84. drainage ring, 841. annular cavity, 842. air outlet cavity, 9. cooling assembly, 91. cooling support frame, 92. cooling connecting plate, 93. cooling plate, 94. water pipe, 95. solenoid valve, 96. atomizing nozzle. DETAILED DESCRIPTION

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0032] Example 1

[0033] Reference Figures 1 to 9 A nuclear power sealing tile casting mold includes a transmission plate 1, an outer mold 2, a mold pad 3, a bushing 4, a mold cover 5, a slide rail 6, a feeding assembly 7, a ventilation assembly 8 and a cooling assembly 9. The transmission plate 1 is fixedly installed at the output end of the centrifuge, the outer mold 2 is fixedly installed at the outer end of the transmission plate 1, and the outer mold 2 is sequentially assembled with a mold pad 3, a bushing 4 and a mold cover 5. The feeding assembly 7 and the ventilation assembly 8 are both movably assembled on the slide rail 6, the discharge end of the feeding assembly 7 is located in the bushing 4, and the ventilation end of the ventilation assembly 8 is located in the middle of the outer end surface of the mold cover 5. Two cooling assemblies 9 are symmetrically fixed on the slide rail 6, and the cooling assembly 9 is used to cool the outer mold 2.

[0034] The mold consists of an outer mold 2, a mold pad 3, a bushing 4, and a mold cover 5. The space between the mold pad 3, the bushing 4 and the mold cover 5 is a mold cavity. After centrifugal casting, a ring-shaped casting is obtained.

[0035] The transmission plate 1 is used to install the mold and is controlled to rotate by the centrifuge. Figure 1 As shown, a platform is provided on the outside of the transmission plate 1, and a cover is installed on the platform. The centrifuge, coupling, bearing and other components are all located in the cover, and the cover provides protection. The output shaft of the centrifuge is connected to the transmission plate 1 to drive the transmission plate 1 to rotate, thereby driving the mold to rotate.

[0036] The outer mold 2 and the transmission plate 1 are generally connected by bolts and nuts.

[0037] The slide rail 6 is installed at one end of the platform and is used to adjust the positions of the feeding assembly 7 and the ventilation assembly 8, and to install the cooling assembly 9.

[0038] The feeding assembly 7 is used to pour the molten metal into the mold cavity.

[0039] The ventilation component 8 is used to guide the air flow inside the casting, improve the cooling efficiency inside the casting, eliminate the temperature gradient of the casting, reduce the segregation of the casting, and at the same time assist in cooling the molten metal in the feed component 7 and adjust the pouring temperature of the molten metal.

[0040] The cooling assembly 9 is used to spray-cool the outer mold 2, thereby improving the cooling efficiency of the outer side of the casting and reducing the segregation phenomenon of the casting.

[0041] Specifically, if Figures 2 to 4 As shown, a connecting plate 11 is fixedly installed on the inner end of the transmission plate 1, and the connecting plate 11 is fixedly installed on the output end of the motor. A cylindrical groove 12 and an air inlet 13 connected to the cylindrical groove 12 are provided on the outer end surface of the connecting plate 11. Through holes are provided in the middle of the transmission plate 1, the mold pad 3 and the mold cover 5, and the ventilation end of the ventilation assembly 8 corresponds to the through hole.

[0042] Through the design of the cylindrical groove 12 and the air inlet 13 on the connecting plate 11, as well as the design of the through hole, an air channel is formed near the axis of the mold. With the action of the ventilation component 8, air circulation can be achieved to assist in cooling the inside of the casting.

[0043] An air pipe may be provided at the outer end of the air inlet 13, and a filter assembly or a purification assembly may be provided at the outer end of the air pipe to ensure that the air flowing to the inside of the casting is free of impurities and clean, so as to avoid affecting the quality of the casting.

[0044] Specifically, if Figure 1 As shown, a slideway is provided on the upper surface of the slide rail 6, and support plates 61 are fixedly installed on both side surfaces of the slide rail 6. Auxiliary wheels 62 are fixedly installed on the upper surface of the support plates 61, and the auxiliary wheels 62 are used to support and position the transmission plate 1 and the outer mold 2.

[0045] The auxiliary wheels 62 are used to support the mold and can rotate without affecting the rotation of the mold.

[0046] In practical applications, an annular groove may be provided at the corresponding position of the outer mold 2 and the auxiliary wheel 62 , and an annular protrusion corresponding to the annular groove may be provided on the surface of the auxiliary wheel 62 to assist in positioning.

[0047] Specifically, if Figure 8 and Figure 9As shown, the cooling assembly 9 includes a cooling support frame 91, a cooling connecting plate 92, a cooling plate 93 and a water pipe 94. The cooling support frame 91 is fixedly mounted on the support plate 61, the cooling connecting plate 92 is fixedly mounted on the upper end of the cooling support frame 91, the cooling plate 93 is fixedly mounted on the inner side of the upper end of the cooling connecting plate 92, the outer wall of the water pipe 94 is evenly fixedly mounted with branch pipes, the outer end of the branch pipe is fixedly mounted with an atomizing nozzle 96, the atomizing nozzle 96 is fixedly mounted on the outer wall of the cooling plate 93, and the liquid outlet end of the atomizing nozzle 96 passes through the cooling plate 93 and faces the outer mold 2, and an electromagnetic valve 95 is installed between the atomizing nozzle 96 and the water pipe 94.

[0048] The water pipe 94 is connected to an external water tank, and the water tank may contain water or coolant.

[0049] The cooling support frame 91 and the cooling connecting plate 92 are used to limit the position of the cooling plate 93; the cooling plate 93 is an arc-shaped plate corresponding to the surface of the outer mold 2, ensuring that the liquid outlet end of each atomizing nozzle 96 is at the same distance from the surface of the outer mold 2; the position of the cooling plate 93 corresponds to the position of the bushing 4, so that its cooling work is mainly applied to the bushing 4, thereby effectively realizing the cooling of the outside of the casting.

[0050] A temperature measuring device can be set on the support plate 61 or other positions to monitor the temperature of the outer mold 2. The temperature data is fed back to the PLC, which then controls the operation of the solenoid valve 95 and dynamically adjusts the flow of the atomizing nozzle 96 to achieve more precise cooling, effectively avoid local overheating, and ensure uniform cooling.

[0051] In this embodiment, two groups of cooling components 9 are provided, which are symmetrically arranged on both sides of the outer mold 2. In other cases, the number of cooling plates 93 can be increased.

[0052] Specifically, if Figure 5 As shown, the feed assembly 7 includes a feed support frame 71 and a feed pipe 72 , and the feed support frame 71 is movably assembled on the slide rail 6 , and a side slit water outlet 74 is opened on the side wall of the discharge end of the feed pipe 72 .

[0053] Specifically, if Figure 3 As shown, the feed end and the discharge end of the feed pipe 72 are both set horizontally, and the middle section of the feed pipe 72 is a downward curved pipe. The diameter of the feed end of the feed pipe 72 is larger than the diameter of the discharge end, and a spiral plate 73 is fixedly installed inside the middle section of the feed pipe 72.

[0054] The molten metal is poured into the feed end of the feed pipe 72, flows out from the discharge end after passing through the feed pipe 72 and falls into the mold cavity. The design of the diameter and curvature of the feed pipe 72 can increase the flow rate of the molten metal, so that the speed of the molten metal can be closer to the rotation speed of the mold, reduce the energy loss of driving the molten metal to rotate, and improve the stability of the mold rotation and casting process.

[0055] A spiral plate 73 is provided in the feed pipe 72 to guide the flow direction of the molten metal so that the molten metal flows out more smoothly from the side slit water outlet 74, thereby avoiding the molten metal colliding with the inner wall of the discharge end of the feed pipe 72 and then changing the flow direction, thereby avoiding the turbulence of the molten metal flow and significantly reducing turbulence.

[0056] In some production operations, the spiral plate 73 may not be provided.

[0057] Specifically, if Figure 5 As shown, the side slit water inlet 74 is opened at an angle, and the side slit water inlet 74 facing the feeding end of the feeding pipe 72 is positioned higher than the other side.

[0058] The inclined design of the side slit water outlet 74 allows the molten metal to flow out evenly along the side slit water outlet 74, avoiding more molten metal flowing out at one end of the side slit water outlet 74. Instead, the molten metal flows out smoothly in a curtain shape and spreads inside the bushing, significantly reducing turbulence and splashing, and allowing the casting to be formed faster.

[0059] The length, width and inclination of the side slit nozzle 74 can be adjusted according to actual production conditions.

[0060] Specifically, if Figure 6 As shown, the ventilation assembly 8 includes a ventilation support frame 81, an air pump 82, a support pipe 83 and a drainage ring 84. The ventilation support frame 81 is movably assembled on the slide rail 6, and the ventilation support frame 81 is located between the outer mold 2 and the feed support frame 71. The air pump 82 is fixedly installed on the upper end of the ventilation support frame 81. The support pipe 83 is fixedly installed on the air pump 82, and the drainage ring 84 is fixedly installed on the upper end of the support pipe 83. The drainage ring 84 is sleeved on the feed pipe 72.

[0061] The ventilation assembly 8 is powered by an air pump 82 to provide airflow, which flows through the support tube 83 to the guide ring 84 and finally flows out. This airflow is used to guide the air flow, form air circulation inside the casting, and cool the inside of the casting.

[0062] The uniform cooling work achieved by the ventilation assembly 8 can effectively suppress the movement of tin elements toward the inner diameter and avoid the occurrence of segregation.

[0063] The lower ends of the feeding support frame 71 and the ventilation support frame 81 are both connected with sliders, which are set in the slideway to limit the position and moving direction of the feeding component 7 and the ventilation component 8; the lower ends of the feeding support frame 71 and the ventilation support frame 81 are both provided with self-locking wheels to facilitate the movement of the feeding component 7 and the ventilation component 8, and to self-lock when fixed.

[0064] Specifically, if Figure 7As shown, the drainage ring 84 is composed of an outer metal ring, a middle metal ring, and an inner metal ring, and the two ends of the outer metal ring are respectively connected to the middle metal ring and the inner metal ring. An annular cavity 841 is formed between the outer metal ring and the middle metal ring, and an air outlet cavity 842 is formed between the middle metal ring and the inner metal ring. The annular cavity 841 is connected to the air outlet cavity 842, and the outlet of the air outlet cavity 842 is away from the outer mold 2.

[0065] The structure of the guide ring 84 allows the airflow in the support tube 83 to be first distributed in the annular cavity 841 and then flow into the air outlet cavity 842 and out, forming a uniform axial airflow and promoting air flow.

[0066] One end of the outlet of the inner metal ring is bent inward to allow the air flow to flow out smoothly.

[0067] For the casting of nuclear power sealing tiles, considering the uneven distribution of temperature field, the tendency of tin elements to be enriched at grain boundaries or the last solidification area, and the segregation phenomenon formed under the action of centrifugal force, in addition to the above-mentioned structural design, the production process also needs to be adjusted. The following mainly explains the pouring temperature and centrifugal force.

[0068] Regarding pouring temperature, segregation can be reduced by lowering the pouring temperature: Shorten the liquid residence time: Use low-temperature pouring technology to make the alloy enter the solidification stage quickly, reduce the flow time of the liquid alloy at high temperature, and thus reduce the risk of low-melting-point tin elements being pushed to the surface; Inhibit interdendritic liquid flow: The dendrite network formed by rapid solidification can close the liquid channel earlier and prevent the tin-rich liquid from migrating to the surface.

[0069] Regarding centrifugal force, the main purpose is to reduce centrifugal force: By reducing the centrifugal force, radial segregation can be alleviated, and the density stratification of copper and tin can be reduced, thereby making the distribution of components inside and outside the casting more uniform; Low-speed rotation may reduce forced convection, contribute to the formation of equiaxed crystals, and refine the microstructure; While appropriately reducing the centrifuge speed, slow down the later pouring speed to increase the inner diameter shrinkage compensation time.

[0070] The processing and testing shown in the following table are carried out for different pouring temperatures and centrifuge speeds.

[0071]

[0072] The data in the above table are part of the data from multiple experiments. According to the Cu-Sn binary phase diagram, the liquidus temperature of CuSn15 is about 950℃, so the pouring temperature was set at 980℃ for the experiment. The table provides the rotational speed of the mold, and the transmission ratio with the centrifuge is approximately 1:1.6. The experiment is carried out gradually from low to high rotational speed. The rotational speed of the centrifuge corresponding to serial number 8 is approximately 1100 rpm.

[0073] In addition, the mold wall thickness can be appropriately increased to increase the cooling rate, ultimately making the percentage of tin in the sealing tile between 14% and 16%, a uniformly distributed 15% content, to ensure the qualification rate and quality of the casting.

[0074] Example 2

[0075] A production process for nuclear power sealing tiles, using the nuclear power sealing tile casting mold as described in Example 1, specifically comprises the following steps: Step 1: Install the mold at the output end of the centrifuge and complete the setting of the feeding component 7, ventilation component 8 and cooling component 9; Install the outer mold 2 on the transmission plate 1, and sequentially assemble the mold pad 3, bushing 4, and mold cover 5 inside the outer mold. Correct the concentricity and dynamic balance between the mold and the centrifuge. Then, move the drainage ring 84 of the ventilation assembly 8 to the outside of the through-hole of the mold cover 5. Move the feed assembly 7 so that the discharge end of the feed pipe 72 passes through the drainage ring 84 and reaches the inside of the bushing 4. Install the cooling assembly 9 on the support plate 61, and place the cooling plate 93 on the outside of the outer mold 2. Complete the mold installation. It is particularly necessary to check whether the pipe connections in the cooling assembly 9 are intact and leak-free.

[0076] Step 2: Preheat the mold by using a gas or electric heating device to preheat the bushing 4 in the mold to 180-300°C, and then evenly spray the paint on the inner wall of the mold pad 3, bushing 4, and mold cover 5; Preheating can avoid the formation of a chill layer or cold shut when the molten metal contacts the cold mold, and can remove the moisture that may be adsorbed in the mold cavity, and make the subsequent sprayed paint dry and form quickly; The coating can be silica powder water-based coating, and the coating thickness is controlled at 0.5-1.5mm. It mainly plays the role of lubrication and protection, and facilitates subsequent demoulding work.

[0077] Step 3: Centrifugal pouring: Start the centrifuge and inject molten metal into the mold through the feed assembly 7. The synergistic effect of the side slit water inlet 74 and the centrifugal force makes the molten metal evenly formed. Simultaneously start the ventilation assembly 8 to assist in heat dissipation on the inner surface of the casting. The centrifuge is started and rotated at a set speed of 1100 rpm. At the same time, molten metal is injected at a pouring temperature of about 1050°C to form the molten metal uniformly. The molten metal is spread evenly and smoothly on the inner wall of the mold in a curtain shape with a suitable direction and initial velocity through the side slit nozzle 74 to avoid impact and splashing. During the pouring process, the pouring speed is slowed down in the later stage to increase the inner diameter shrinkage compensation time; During the pouring process, the ventilation assembly 8 is activated to generate a uniform axial airflow, thereby promoting air flow and assisting in cooling the inside of the casting.

[0078] Step 4: Centrifugal solidification. After pouring is completed, the centrifuge and ventilation assembly 8 continue to work, and the cooling assembly 9 is started at the same time. Through ventilation and heat dissipation inside the casting and spray cooling outside the mold, internal and external coordinated cooling is achieved, which reduces the solidification time of the molten metal, inhibits the flow of liquid phase between dendrites, and reduces segregation. During the operation of the cooling assembly 9, the temperature of the outer mold 2 is monitored by a temperature measuring device, and the temperature data is fed back to the PLC, which then controls the operation of the solenoid valve 95, dynamically adjusts the flow of the atomizing nozzle 96, and ensures that the cooling intensity is moderate, achieving more accurate cooling, effectively avoiding local overheating, and ensuring uniform cooling. Through coordinated cooling of the inside and outside, the casting is solidified sequentially from the outside to the inside, and the solidification time is shortened, thereby effectively suppressing the segregation of tin elements.

[0079] Step 5: Casting removal and post-processing: After the casting cools to a certain temperature below the solidus line, the centrifuge is stopped and the casting is taken out. The casting is then cleaned and non-destructive testing is performed. The cleaning work of castings mainly includes preliminary cleaning work such as sand removal, grinding of burrs and other preliminary cleaning work; Non-destructive testing mainly involves penetrant testing (PT) and ultrasonic testing (UT) on castings to check for internal defects such as shrinkage, pores, and slag inclusions.

[0080] The above content is only a preferred embodiment of the present invention. For ordinary technicians in this field, according to the concept of the present invention, many changes can be made in the specific implementation method and application scope. As long as these changes do not deviate from the concept of the present invention, they all fall within the scope of protection of the present invention.

Claims

1. A casting mold for a nuclear power sealing tile, characterized by: It includes a transmission plate, an outer mold, a mold pad, a bushing, a mold cover, a slide rail, a feeding assembly, a ventilation assembly and a cooling assembly. The transmission plate is fixedly installed on the output end of the centrifuge, the outer mold is fixedly installed on the outer end of the transmission plate, the outer mold is sequentially equipped with a mold pad, a bushing and a mold cover, the feeding assembly and the ventilation assembly are both movably assembled on the slide rail, the discharge end of the feeding assembly is located in the bushing, the ventilation end of the ventilation assembly is located in the middle of the outer end surface of the mold cover, the two cooling assemblies are symmetrically fixed on the slide rail, and the cooling assembly is used to cool the outer mold.

2. A nuclear power sealing tile casting mold according to claim 1, characterized in that: A connecting plate is fixedly installed on the inner end of the transmission plate, and the connecting plate is fixedly installed on the output end of the motor. A cylindrical groove and an air inlet hole connected to the cylindrical groove are provided on the outer end surface of the connecting plate. Through holes are provided in the middle of the transmission plate, mold pad and mold cover, and the ventilation end of the ventilation assembly corresponds to the through hole.

3. A nuclear power sealing tile casting mold according to claim 1, characterized in that: A slideway is provided on the upper surface of the slide rail, support plates are fixedly installed on both sides of the slide rail, auxiliary wheels are fixedly installed on the upper surface of the support plate, and the auxiliary wheels are used to support and position the transmission plate and the outer mold.

4. A nuclear power sealing tile casting mold according to claim 3, characterized in that: The cooling assembly includes a cooling support frame, a cooling connecting plate, a cooling plate and a water pipe. The cooling support frame is fixedly installed on the support plate, the cooling connecting plate is fixedly installed on the upper end of the cooling support frame, a cooling plate is fixedly installed on the inner side of the upper end of the cooling connecting plate, branch pipes are evenly fixedly installed on the outer wall of the water pipe, an atomizing nozzle is fixedly installed on the outer end of the branch pipe, the atomizing nozzle is fixedly installed on the outer wall of the cooling plate, and the liquid outlet end of the atomizing nozzle passes through the cooling plate and faces the outer mold, and a solenoid valve is installed between the atomizing nozzle and the water pipe.

5. The nuclear power sealing tile casting mold according to claim 1, characterized in that: The feed assembly includes a feed support frame and a feed pipe, and the feed support frame is movably assembled on a slide rail, and a side slit water outlet is opened on the side wall of the discharge end of the feed pipe.

6. A nuclear power sealing tile casting mold according to claim 5, characterized in that: The feed end and the discharge end of the feed pipe are both arranged horizontally, and the middle section of the feed pipe is a downwardly curved pipe. The diameter of the feed end of the feed pipe is larger than the diameter of the discharge end, and a spiral plate is fixedly installed inside the middle section of the feed pipe.

7. A nuclear power sealing tile casting mold according to claim 6, characterized in that: The side slit water inlet is opened at an angle, and the position of one side of the side slit water inlet toward the feeding end of the feeding pipe is higher than the other side.

8. The nuclear power sealing tile casting mold according to claim 5, characterized in that: The ventilation assembly includes a ventilation support frame, an air pump, a support pipe and a drainage ring. The ventilation support frame is movably assembled on a slide rail, and the ventilation support frame is located between the outer mold and the feeding support frame. The air pump is fixedly installed on the upper end of the ventilation support frame. The support pipe is fixedly installed on the air pump, and the drainage ring is fixedly installed on the upper end of the support pipe. The drainage ring is sleeved on the feeding pipe.

9. A nuclear power sealing tile casting mold according to claim 8, characterized in that: The drainage ring is composed of an outer metal ring, an intermediate metal ring, and an inner metal ring, the two ends of the outer metal ring are respectively connected to the intermediate metal ring and the inner metal ring, an annular cavity is formed between the outer metal ring and the intermediate metal ring, an air outlet cavity is formed between the intermediate metal ring and the inner metal ring, and the annular cavity is connected to the air outlet cavity, and the outlet of the air outlet cavity is far away from the outer mold.

10. A process for producing nuclear power sealing tiles, using the nuclear power sealing tile casting mold according to any one of claims 1 to 9, specifically comprising the following steps: Step 1: Install the mold at the output end of the centrifuge and complete the settings of the feeding assembly, ventilation assembly, and cooling assembly; Step 2: Preheat the mold by using a gas or electric heating device to preheat the bushing in the mold to 180-300°C, and then evenly spray the heat-resistant coating on the inner wall of the mold pad, bushing, and mold cover; Step 3: Centrifugal pouring: Start the centrifuge and inject the molten metal into the mold through the feeding assembly. The synergistic effect of the side slit water inlet and centrifugal force makes the molten metal evenly formed. The ventilation assembly is started simultaneously to assist in heat dissipation on the inner surface of the casting. Step 4: Centrifugal solidification. After pouring is completed, the centrifuge and ventilation components continue to work, and the cooling component is started at the same time. Through ventilation and heat dissipation on the inside of the casting and spray cooling on the outside of the mold, internal and external coordinated cooling is achieved, which reduces the solidification time of the molten metal, inhibits the flow of liquid phase between dendrites, and reduces segregation. Step 5: Casting removal and post-processing: After the casting cools to a certain temperature below the solidus line, stop the centrifuge and take out the casting. Then, clean the casting and perform non-destructive testing.

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