Horizontal centrifugal casting high-precision active control equipment and process method based on magnetic suspension technology

Abstract

The invention relates to the technical field of horizontal centrifugal casting equipment, in particular to horizontal centrifugal casting high-precision active control equipment based on the magnetic levitation technology and a technological method.The horizontal centrifugal casting high-precision active control equipment based on the magnetic levitation technology comprises an electric control cabinet, a cold mold and a carrier roller shaft and further comprises a transmission system used for providing power for the equipment; the radial suspension supporting structure is used for providing radial force support for the carrier roller shaft so as to realize suspension in the radial direction; the axial suspension supporting structure is used for providing axial force support for the carrier roller shaft so as to realize suspension in the axial direction; the position detection and active control system is integrated, radial and axial position offset signals in the cold type rotating process can be collected in real time, the suspension supporting force is dynamically adjusted through the magnetic suspension system, high-precision active control over the rotating posture of the cold type is achieved, posture offset in the rotating process is effectively restrained, and the stability of the rotating posture of the cold type is improved. Contact friction between the cold mold and peripheral parts is avoided, abrasion of the outer surface of the cold mold is reduced fundamentally, and the service life of the cold mold is prolonged.

Description

Technical Field

[0001] This invention relates to the field of horizontal centrifugal casting equipment technology, specifically to a high-precision active control device and process method for horizontal centrifugal casting based on magnetic levitation technology. Background Technology

[0002] With the nation's vigorous promotion of green and low-carbon development and enterprises focusing on energy conservation, emission reduction, and quality and efficiency improvement in industrial transformation, manufacturing enterprises face urgent pressure to upgrade their processes and are ushering in strategic opportunities for industrial structure optimization. Horizontal centrifugal casting, with its advantages of smooth and stable filling, high casting yield, excellent density, low incidence of defects such as porosity and inclusions, and outstanding mechanical properties, can form composite layer structures, effectively improving overall cost-effectiveness. It has become one of the core processes for forming roll-type parts and occupies an irreplaceable position in the roll production field. Compared with traditional casting processes, horizontal centrifugal casting can precisely achieve a perfect combination of the wear-resistant layer of the roll body and the toughness layer of the core, significantly improving the service life and stability of the roll. At the same time, it effectively improves the utilization rate of metal materials, reduces energy consumption and waste emissions during production, and perfectly meets the current high-quality and green development needs of the manufacturing industry.

[0003] In horizontal centrifugal casting, the combined effects of centrifuge operation, mold rotation, molten metal pouring and solidification, and uneven solidification layer density leading to eccentric loading cause the system to endure long-term centrifugal force fluctuations and dynamic loads caused by molten metal impact. Facing the strong coupling of force, heat, and fluid fields from high-speed rotation, high-temperature radiation, and molten metal flow impact, vibration is easily induced. The causes of this type of vibration are multi-source: at the equipment level, spindle wear, coaxiality deviation, bearing damage or insufficient lubrication, drive system speed fluctuations, and unstable installation due to loose anchor bolts; at the mold level, uneven wall thickness, material density imbalance causing center of gravity shift, and excessive clearance between the mold and spindle; at the process level, unstable molten metal pouring speed and flow rate, improper control of the pouring interval, and excessively rapid cooling; and at the material level, excessive impurities in the molten metal and large temperature fluctuations leading to uneven solidification shrinkage and internal stress. All of these can contribute to vibration. Vibration has a significant negative impact on horizontal centrifugal casting production and casting quality. It can cause unevenness and inconsistent wall thickness in the casting, damage the metallurgical bond between the wear-resistant layer and the core of the roll, greatly increase the incidence of defects such as porosity, inclusions, and cracks, and reduce the density and mechanical properties of the casting. It can also accelerate the wear of key components such as the centrifuge spindle and bearings, shorten the service life of the equipment, and in severe cases, cause equipment failure and shutdown, or even cause safety accidents such as mold displacement and molten metal splashing, which seriously affects the continuous casting production of rolls.

[0004] However, current traditional vibration control measures, such as conventional equipment calibration, mold optimization, and process parameter control, while mitigating vibration problems to some extent, are limited by their technical characteristics and cannot cope with complex dynamic loads under high-speed rotation and multi-field coupling. They suffer from drawbacks such as insufficient vibration suppression accuracy, narrow applicable operating conditions, and poor long-term service stability, failing to address the root causes of vibration's impact on the casting system. Therefore, there is an urgent need to introduce more advanced support and vibration reduction technologies to reduce or suppress casting defects and hazards caused by vibration.

[0005] Magnetic levitation technology is characterized by fast response, high precision, compact structure, and ease of multi-degree-of-freedom control. Among them, magnetic levitation bearings, with their core advantages of non-contact support, active vibration reduction, and high-precision attitude control, can effectively overcome the limitations of traditional measures and become an ideal solution to the vibration problem in horizontal centrifugal casting. Summary of the Invention

[0006] The purpose of this invention is to provide a high-precision active control device and process method for horizontal centrifugal casting based on magnetic levitation technology. This device can keep the cold mold idler rollers in a suspended state during centrifugal casting, maintaining stable rotation around their own axis and ensuring precise speed, thus significantly reducing vibration between the cold mold and the idler rollers during centrifugal rotation. Simultaneously, it can detect and provide real-time feedback on the position and speed of the idler rollers, ensuring the cold mold remains in a stable working state.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a high-precision active control device for horizontal centrifugal casting based on magnetic levitation technology, comprising an electrical control cabinet, a cold mold, and idler rollers, and further comprising: The transmission system is used to provide power to the equipment; A radial suspension support structure, wherein the radial suspension support structure provides radial force support for the roller shaft to achieve radial suspension; An axial suspension support structure provides axial force support for the idler roller shaft to achieve axial suspension. A speed and position detection system is used to detect the position and rotation speed of the idler roller shaft in real time, and to feed back the detection signal in real time to control the idler roller shaft to be in a horizontally suspended state. Protective bearings are used to enable the cold-type idler roller shaft to rotate.

[0008] Preferably, the transmission system consists of a drive motor, a universal coupling, a cold-formed idler roller, and a cold-formed idler roller shaft. The power input end of the universal coupling is rigidly connected to the output shaft of the drive motor. The cold-formed idler roller is coaxial with the idler roller shaft and rotates around it. The roller surface of the cold-formed idler roller is in contact with the annular groove on the outer surface of the cold-formed roller and is subjected to friction transmission.

[0009] Preferably, the radial suspension support structure comprises an eight-pole radial magnetic levitation bearing, a displacement detection module, a controller, and a power amplifier. The eight-pole radial magnetic levitation bearing consists of an eight-pole radial magnetic levitation bearing rotor and an eight-pole radial magnetic levitation bearing stator. The eight-pole radial magnetic levitation bearing rotor is coaxially fixed to the outside of the idler roller shaft. The eight-pole radial magnetic levitation bearing stator is coaxially fitted onto the outside of the eight-pole radial magnetic levitation bearing rotor. The inner wall of the stator of the eight-pole radial magnetic levitation bearing has a ring array of magnetic poles, with a total of 8 sets of magnetic poles. A micron-level uniform air gap is reserved between the magnetic poles and the outer wall of the eight-pole radial magnetic levitation bearing rotor. The surface of the eight-pole radial magnetic levitation bearing is provided with a bearing seat, and the eight-pole radial magnetic levitation bearing is assembled on the inner side of the bearing seat. A winding coil A is wound on the magnetic pole.

[0010] Preferably, the axial suspension support structure comprises two symmetrically arranged axial magnetic levitation bearings, a thrust disk, an axial displacement detection sensor, a main control unit, and a power drive module. The thrust disk is coaxially fixed to the end of the cold-type idler roller shaft. The two axial magnetic levitation bearings are respectively mounted on supports on both sides of the thrust disk. The axial displacement detection sensor is mounted on the support of the thrust disk. The main control unit is electrically connected to the axial displacement detection sensor and the power drive module. A winding coil B is provided inside the axial magnetic levitation bearing, and the power drive module is electrically connected to the winding coil B. The entire axial suspension support structure is mounted on a bearing seat.

[0011] Preferably, the speed and position detection system consists of a radial speed and position sensor, an axial speed and position sensor, and a signal conditioning unit. The radial speed and position sensor consists of a radial speed sensor probe and a radial position sensor probe, and the axial speed and position sensor consists of an axial speed sensor probe and an axial position sensor probe. The signal conditioning unit is integrated into the electrical control cabinet.

[0012] Preferably, the protective bearing is coaxially sleeved on the outside of the cold idler shaft, and a preset safety gap is reserved between the inner ring of the protective bearing and the outer wall of the cold idler shaft, and the safety gap is smaller than the working air gap of the radial magnetic levitation bearing.

[0013] A high-precision active control process for horizontal centrifugal casting based on magnetic levitation technology includes the following steps: Step 1: Equipment Assembly and Preliminary Preparation: Place the cold mold on the cold mold idler roller, ensuring that the pre-set annular groove of the cold mold shell makes precise surface contact with the idler roller. Check that the assembly status of each component is qualified. At the same time, complete the mold pretreatment, raw material melting and refining, and cold mold preheating. Step 2: The two axial magnetic levitation bearings of the winding coil generate a balanced bidirectional axial attraction force on the thrust plate, causing the winding coil A to move in four orthogonal directions (X+, X-, Y+, Y-), thus realizing the start of the magnetic levitation support system for the cold idler shaft. The control system is started through the electrical control cabinet, and a constant bias current is supplied to the winding coil B in the axial magnetic levitation bearing, so that the two axial magnetic levitation bearings generate a balanced bidirectional axial attraction force on the thrust plate. The idler shaft is initially suspended in the axial direction at the preset equilibrium position. At the same time, the eight sets of winding coils A of the eight-pole radial magnetic levitation bearing generate radial support force in four orthogonal directions (X+, X-, Y+, Y-), so that the cold idler shaft is suspended in the radial direction, completing the initialization of the non-contact suspension attitude of the cold idler shaft. Step 3: Start the transmission system and detection system: Start the drive motor, which drives the cold-formed roller shaft, cold-formed roller and cold-formed roller to rotate through the universal coupling. At the same time, start the radial speed position sensor and axial speed position sensor to collect signals in real time. After the signal conditioning unit filters, amplifies and linearizes the signal, it is fed back to the main control unit. The main control unit adjusts the output torque of the drive motor to make the cold-formed roller reach the preset stable speed. Step 4: Implement layered casting operation: After the cold mold rotation speed stabilizes, inject the outer layer of wear-resistant alloy molten metal and the inner layer of tough material molten metal into the cold mold in sequence. During the casting process, the main control unit continuously receives position and rotation speed detection signals. If radial or axial displacement of the cold mold idler shaft is detected, the excitation current of the corresponding magnetic levitation bearing is immediately dynamically adjusted to push the cold mold idler shaft to reset, ensuring the stability of the cold mold rotation posture. Step 5, Solidification, Cooling and Attitude Maintenance: Keep the cold mold rotating at a specific speed until the molten metal solidifies naturally, and then undergo forced cooling and natural cooling to room temperature. During the cooling process, the magnetic levitation support and detection system continue to work. Step 6, Post-processing: Turn off the drive motor and magnetic levitation bearing system, demold, clean and inspect. Qualified castings are annealed, and if necessary, quenched and tempered to obtain the finished product.

[0014] Preferably, in step one, the cold preheating temperature is 200-400℃, the preheating time is 1-2 hours, and in step three, the fluctuation of the preset stable rotation speed is ≤±5r / min.

[0015] Preferably, in step four, the pouring temperature of the outer wear-resistant alloy molten metal is 1400–1500℃, the pouring temperature of the inner toughness material molten metal is 1380–1480℃, the pouring speed is 0.5–2 kg / s, and the interval between two pours is 3–10 minutes.

[0016] Preferably, in step five, the rotation time of the molten metal during the natural solidification stage is 10 to 30 minutes, the forced cooling rate is 5 to 15°C / min, the forced cooling endpoint temperature is 200 to 300°C, and in step six, the annealing temperature is 600 to 700°C, and the annealing time is 2 to 4 hours.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention integrates a position detection and active control system, which can collect radial and axial position offset signals during the rotation of the cold mold in real time. By dynamically adjusting the suspension support force through the magnetic levitation system, it can achieve high-precision active control of the rotation attitude of the cold mold and effectively suppress attitude offset during the rotation process. This avoids contact friction between the cold mold and surrounding components, reduces wear on the outer surface of the cold mold from the source, and extends the service life of the cold mold.

[0018] 2. This invention completely eliminates the contact support method of traditional mechanical bearings by using a magnetic levitation non-contact support structure and speed-position coordinated control. Stable speed and attitude control can make the molten metal filling more uniform and solidification more stable, further improving the density of the casting and greatly reducing the surface defects of the casting caused by cold mold wear and the mechanical property risks caused by uneven density.

[0019] 3. The position detection, speed detection and active control functions of this invention form a collaborative closed loop, which can adapt to the rotation control requirements of cold molds with different diameters and lengths. Through parameter adaptive adjustment, it can achieve precise control of the casting process of rolls of various specifications, fill the technical gap of speed-position collaborative active control in the field of centrifugal casting, and improve the process adaptability and intelligence level. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure in this invention; Figure 2 This is a schematic diagram of the disassembled structure in this invention; Figure 3 This is a schematic diagram of the eight-pole radial magnetic levitation bearing in this invention; Figure 4 This is a schematic cross-sectional view of the axial magnetic levitation bearing in this invention. Figure 5 This is a schematic diagram of the radial velocity position sensor in this invention; Figure 6 In this invention Figure 2 Enlarged structural diagram at point I; Figure 7 This is a schematic diagram of the axial velocity position sensor in this invention; Figure 8 In this invention Figure 2 Enlarged structural diagram at point II; Figure 9 This is a schematic diagram of the replacement of the permanent magnet and piezoelectric ceramic actuator in Embodiment 1 of the present invention.

[0021] In the diagram: 1. Cold-formed roller; 2. Cold-formed roller shaft; 3. Cold-formed roller; 4. Bearing housing; 5. Universal coupling; 6. Drive motor; 7. Electrical control cabinet; 8. Protective bearing; 9. Radial velocity and position sensor; 10. Eight-pole radial magnetic levitation bearing; 11. Axial magnetic levitation bearing; 12. Thrust plate; 13. Axial velocity and position sensor; 14. Winding coil A; 15. Eight-pole radial magnetic levitation bearing stator; 16. Eight-pole radial magnetic levitation bearing rotor; 17. Winding coil B; 18. Radial velocity sensor probe; 19. Radial position sensor probe; 20. Axial velocity sensor probe; 21. Axial position sensor probe; 22. Permanent magnet; 23. Piezoelectric ceramic actuator. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1: Please refer to Figures 1-8 As shown, a high-precision active control device for horizontal centrifugal casting based on magnetic levitation technology includes an electrical control cabinet 7, a cold mold 1, and a roller shaft. It also includes a transmission system, a radial suspension support structure, an axial suspension support structure, a speed and position detection system, and a protective bearing. The transmission system provides power to the device. The radial suspension support structure provides radial force support to the roller shaft to achieve radial suspension. The axial suspension support structure provides axial force support to the roller shaft to achieve axial suspension. The speed and position detection system is used to detect the position and rotation speed of the roller shaft in real time and feed back the detection signal in real time to control the roller shaft to be in a horizontal suspension state. The protective bearing is used to enable the cold mold roller shaft 2 to rotate.

[0024] The transmission system consists of a drive motor 6, a universal coupling 5, a cold-formed idler roller 3, and a cold-formed idler roller shaft 2. The power input end of the universal coupling 5 is rigidly connected to the output shaft of the drive motor 6, and the power output end is coaxially and rigidly connected to the cold-formed idler roller shaft. The cold-formed idler roller 3 is coaxial with the idler roller shaft and rotates around its outer side. The roller surface of the cold-formed idler roller 3 is in contact with the annular groove on the outer surface of the cold-formed 1 and is subjected to friction transmission. When the drive motor starts and outputs torque, the torque is transmitted to the cold-formed idler roller in sequence through the universal coupling and the cold-formed idler roller shaft. The cold-formed idler roller drives the cold-formed 1 to rotate synchronously around its own axis by means of the friction between the cold-formed 1 outer shell groove.

[0025] The radial suspension support structure consists of an eight-pole radial magnetic levitation bearing 10, a displacement detection module, a controller, and a power amplifier. The eight-pole radial magnetic levitation bearing 10 is composed of an eight-pole radial magnetic levitation bearing rotor 16 and an eight-pole radial magnetic levitation bearing stator 15. The eight-pole radial magnetic levitation bearing rotor 16 is coaxially fixed to the outside of the idler roller shaft, and the eight-pole radial magnetic levitation bearing stator 15 is coaxially fitted to the outside of the eight-pole radial magnetic levitation bearing rotor 16. The inner wall of the stator of the eight-pole radial magnetic levitation bearing 10 has a ring array of magnetic poles, with a total of 8 sets of magnetic poles. A micron-level uniform air gap is reserved between the magnetic poles and the outer wall of the eight-pole radial magnetic levitation bearing rotor 16. The 8 sets of magnetic poles are paired in pairs in four orthogonal directions (X+, X-, Y+, Y-) to form a constraint on the radial four degrees of freedom of the idler roller shaft. The surface of the eight-pole radial magnetic levitation bearing 10 is provided with a bearing seat 4, and the eight-pole radial magnetic levitation bearing 10 is assembled inside the bearing seat 4. A winding coil A14 is wound on the magnetic pole.

[0026] The axial suspension support structure consists of two symmetrically arranged axial magnetic levitation bearings 11, a thrust disk 12, an axial displacement detection sensor, a main control unit, and a power drive module. The thrust disk 12 is coaxially fixed to the end of the cold-type idler roller shaft 2. The two axial magnetic levitation bearings 11 are respectively mounted on the supports on both sides of the thrust disk 12. The end faces of the axial magnetic levitation bearings 11 and the thrust disk 12 correspond one-to-one and are reserved with micron-level uniform air gaps to form a bidirectional axial force constraint structure. The axial displacement detection sensor is mounted on the support of the thrust disk 12 to collect the axial offset signal of the cold-type idler roller shaft in real time. The main control unit is electrically connected to the axial displacement detection sensor and the power drive module. The axial magnetic levitation bearing 11 has a winding coil B17 inside, and the power drive module is electrically connected to the winding coil B17. The entire axial suspension support structure is mounted on the bearing seat 4.

[0027] The speed and position detection system consists of a radial speed and position sensor 9, an axial speed and position sensor 13, and a signal conditioning unit. The radial speed and position sensor 9 integrates radial position detection and rotational speed detection functions and is arranged in four orthogonal directions (X+, X-, Y+, Y-) corresponding to the cold idler shaft. Its core is an integrated eddy current sensor component. The radial speed and position sensor 9 consists of a radial speed sensor probe 18 and a radial position sensor probe 19, both of which maintain a preset detection gap with the cold idler shaft. The axial speed and position sensor 13 integrates axial position detection and rotational speed detection functions and is arranged corresponding to the axial end face of the thrust plate. The axial speed and position sensor 13 consists of an axial speed sensor probe 20 and an axial position sensor probe 21, both of which maintain a preset detection gap with the thrust plate. The signal conditioning unit is integrated in the electrical control cabinet 7 and is electrically connected to the radial speed and position sensor and the axial speed and position sensor 13 respectively through shielded cables. It also communicates with the main control unit of the magnetic levitation system.

[0028] The protective bearing 8 is coaxially sleeved on the outside of the cold idler shaft 2. Its outer ring is fixed in the bearing housing by interference fit. A preset safety gap is reserved between the inner ring of the protective bearing 8 and the outer wall of the cold idler shaft. This safety gap is smaller than the working air gap of the radial magnetic levitation bearing, thus forming an emergency support constraint on the cold idler shaft.

[0029] Example 2: A high-precision active control device for horizontal centrifugal casting based on magnetic levitation technology includes an electrical control cabinet 7, a cold mold 1, and a roller shaft. It also includes a permanent magnet 22 positioned between an eight-pole radial magnetic levitation bearing stator 15 and an eight-pole radial magnetic levitation bearing rotor 16. A piezoelectric ceramic actuator 23 is positioned on the side of the permanent magnet 22 closest to the eight-pole radial magnetic levitation bearing stator 15. The core component is the piezoelectric ceramic actuator 23, which attaches a small piece of permanent magnet 22 to the piezoelectric ceramic. When the piezoelectric ceramic is energized, it exhibits precise expansion and contraction at the nanometer to micrometer level. This expansion and contraction causes the permanent magnet / magnetic conductor to move, thereby subtly changing the air gap distance between it and the rotor. Based on the strong nonlinear relationship between magnetic force and air gap distance, the magnetic force ≈ 1 / air gap. 2 Even a tiny change in the air gap can cause a significant change in the magnetic force, thereby achieving rapid adjustment of the levitation force. It is particularly suitable for applications that are extremely sensitive to high-frequency micro-amplitude vibrations. In the axial magnetic levitation bearing 11, two symmetrical piezoelectric ceramic actuators 23 with permanent magnets 22 can be aligned with the thrust plate 12. By controlling the voltage of the piezoelectric ceramic, it can produce micro-expansion and contraction, thereby quickly offsetting the axial movement caused by the impact of the casting liquid flow or solidification shrinkage. It is like a "fine-tuning valve of the magnetic field", adjusting the magnetic circuit mechanically rather than electromagnetically.

[0030] A high-precision active control process for horizontal centrifugal casting based on magnetic levitation technology is proposed. The process primarily targets the field of centrifugal casting rolls, particularly addressing the issues of uneven roll density and wear on the outer surface of the cold-casting mold caused by vibration during centrifugal casting. The key focus is on designing a magnetic levitation control system to achieve high-precision active control, specifically including: Step 1: Complete equipment assembly and preliminary preparation: Place the cold mold 1 on the cold mold idler roller 3, ensuring that the pre-set annular groove of the cold mold 1 shell makes precise surface contact with the cold mold idler roller 3. Check the assembly status of each component. The eight-pole radial magnetic levitation bearing 10 is concentrically fixed to the bearing seat 4 with the cold mold idler roller shaft 2. The axial magnetic levitation bearing 11 is horizontally fitted with the thrust plate 12 with a micron-level clearance and fixed to the bearing seat 4. The radial speed position sensor 9 is concentrically fixed to the bearing seat 4 with the cold mold idler roller shaft 2, and the speed sensor probe 18 and the radial position sensor probe 19 both maintain a preset detection gap with the cold mold idler roller shaft 2. The speed sensor probe B20 and the axial position sensor probe 21 of the axial speed position sensor 13 both maintain a preset detection gap with the thrust plate 12. Protect the bearing 8 and firmly fix it to the bearing seat 4. At the same time, complete the mold pretreatment, raw material melting and refining, and cold mold 1 preheating (uniform preheating at 200-400℃ for 1-2 hours). Step 2: Start the magnetic levitation support system: Start the control system through the electrical control cabinet 7. First, a constant bias current is supplied to the winding coil B17 of the axial magnetic levitation bearing 11, so that the two axial magnetic levitation bearings 11 generate a balanced bidirectional axial attraction force on the thrust plate 12, and the cold idler shaft 2 is initially suspended in the axial direction at the preset equilibrium position; at the same time, the eight winding coils A14 of the eight-pole radial magnetic levitation bearing 10 generate radial support force in four orthogonal directions X+, X-, Y+, and Y-, so that the cold idler shaft 2 is suspended in the radial direction, and the contactless suspension attitude initialization of the cold idler shaft 2 is completed. Step 3: Start the transmission and detection system: Start the drive motor 6. The torque is transmitted to the cold mold roller shaft 2 through the universal coupling 5, which drives the cold mold roller 3 to rotate synchronously. The cold mold roller 3 drives the cold mold 1 to rotate around its own axis through friction transmission with the cold mold 1. At the same time, the radial speed position sensor 9 and the axial speed position sensor 13 are started to collect the radial and axial position signals and speed signals of the cold mold roller shaft 2 in real time. After the signals are filtered, amplified and linearized by the signal conditioning unit in the electrical control cabinet 7, they are fed back to the main control unit. The main control unit adjusts the output torque of the drive motor 6 according to the preset speed parameters (fluctuation ≤ ±5r / min) so that the cold mold 1 reaches the stable speed required for casting. Step 4: Implement layered casting operation: After the rotation speed of the cold mold 1 stabilizes, inject the outer layer of wear-resistant alloy molten metal at 1400-1500℃ into the cold mold 1 at a speed of 0.5-2 kg / s; during the casting process, the main control unit of the electrical control cabinet 7 continuously receives position and rotation speed detection signals. If radial displacement of the cold mold idler shaft 2 is detected, immediately adjust the excitation current of the corresponding magnetic pole of the eight-pole radial magnetic levitation bearing 10, and push the cold mold idler shaft 2 to reset through dynamic adjustment of radial support force; if axial displacement occurs, adjust the excitation current of the two axial magnetic levitation bearings 11, and use the difference in adsorption force to push the cold mold idler shaft 2 to reset, ensuring the stable rotation posture of the cold mold 1; after the outer layer of molten metal solidifies to a semi-solid state 3-10 minutes after casting, inject the inner layer of tough material molten metal at 1380-1480℃ at the same speed to achieve good metallurgical bonding; Step 5, Solidification, Cooling, and Attitude Maintenance: After the inner layer of molten metal is poured, keep the cold mold 1 rotating at a specific speed for 10-30 minutes to allow the molten metal to solidify naturally. After complete solidification, start the cooling system and force-cool it to 200-300°C at a rate of 5-15°C / min, then let it cool naturally to room temperature with the cold mold 1. During the cooling process, the magnetic levitation support and detection system continue to work to ensure the stability of the rotational attitude of the cold mold 1 and avoid the impact of vibration caused by temperature changes on the solidification quality of the casting. If the system malfunctions and the magnetic levitation support fails, the protective bearing 8 will immediately play an emergency support role to prevent component damage and trigger the shutdown protection program. Step 6, Post-processing: After the cold mold 1 has cooled to room temperature, first turn off the drive motor 6. After the cold mold 1 has completely stopped rotating, turn off the magnetic levitation bearing system. Then, demolding and cleaning are carried out. The casting is subjected to visual inspection, ultrasonic / radiographic flaw detection and hardness testing. Qualified castings are annealed at 600-700℃ for 2-4 hours to relieve stress. If necessary, quenching and tempering are carried out to improve wear resistance. Finally, qualified roll products are obtained.

[0031] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-precision active control device for horizontal centrifugal casting based on magnetic levitation technology, comprising an electrical control cabinet (7), a cold mold (1), and a roller shaft, characterized in that, Also includes: The transmission system is used to provide power to the equipment; A radial suspension support structure, wherein the radial suspension support structure provides radial force support for the roller shaft to achieve radial suspension; An axial suspension support structure provides axial force support for the idler roller shaft to achieve axial suspension. A speed and position detection system is used to detect the position and rotation speed of the idler roller shaft in real time, and to feed back the detection signal in real time to control the idler roller shaft to be in a horizontally suspended state. Protect the bearing to enable the cold idler roller shaft (2) to rotate.

2. The high-precision active control equipment for horizontal centrifugal casting based on magnetic levitation technology according to claim 1, characterized in that: The transmission system consists of a drive motor (6), a universal coupling (5), a cold-formed idler roller (3) and a cold-formed idler roller shaft (2). The power input end of the universal coupling (5) is rigidly connected to the output shaft of the drive motor (6). The cold-formed idler roller (3) is coaxial with the idler roller shaft and rotates around it. The roller surface of the cold-formed idler roller (3) is in contact with the annular groove on the outer surface of the cold-formed roller (1) and is subjected to friction transmission.

3. The high-precision active control equipment for horizontal centrifugal casting based on magnetic levitation technology according to claim 1, characterized in that: The radial suspension support structure consists of an eight-pole radial magnetic levitation bearing (10), a displacement detection module, a controller, and a power amplifier. The eight-pole radial magnetic levitation bearing (10) consists of an eight-pole radial magnetic levitation bearing rotor (16) and an eight-pole radial magnetic levitation bearing stator (15). The eight-pole radial magnetic levitation bearing rotor (16) is coaxially fixed to the outside of the idler roller shaft. The eight-pole radial magnetic levitation bearing stator (15) is coaxially fitted onto the outside of the eight-pole radial magnetic levitation bearing rotor (16). The inner wall of the stator of the eight-pole radial magnetic levitation bearing (10) is arranged with magnetic poles in a ring array. The number of magnetic poles is 8. A micron-level uniform air gap is reserved between the magnetic poles and the outer wall of the eight-pole radial magnetic levitation bearing rotor (16). The surface of the eight-pole radial magnetic levitation bearing (10) is provided with a bearing seat (4), and the eight-pole radial magnetic levitation bearing (10) is assembled on the inner side of the bearing seat (4). A winding coil A (14) is wound on the magnetic pole.

4. The high-precision active control equipment for horizontal centrifugal casting based on magnetic levitation technology according to claim 1, characterized in that: The axial suspension support structure consists of two symmetrically arranged axial magnetic levitation bearings (11), a thrust disk (12), an axial displacement detection sensor, a main control unit, and a power drive module. The thrust disk (12) is coaxially fixed to the end of the cold-type idler roller shaft (2). The two axial magnetic levitation bearings (11) are respectively mounted on the brackets on both sides of the thrust disk (12). The axial displacement detection sensor is mounted on the bracket of the thrust disk (12). The main control unit is electrically connected to the axial displacement detection sensor and the power drive module. The axial magnetic levitation bearing (11) is provided with a winding coil B (17). The power drive module is electrically connected to the winding coil B (17). The entire axial suspension support structure is mounted on the bearing seat (4).

5. The high-precision active control equipment for horizontal centrifugal casting based on magnetic levitation technology according to claim 1, characterized in that: The speed and position detection system consists of a radial speed and position sensor (9), an axial speed and position sensor (13), and a signal conditioning unit. The radial speed and position sensor (9) consists of a radial speed sensor probe (18) and a radial position sensor probe (19). The axial speed and position sensor (13) consists of an axial speed sensor probe (20) and an axial position sensor probe (21). The signal conditioning unit is integrated in the electrical control cabinet (7).

6. The high-precision active control equipment for horizontal centrifugal casting based on magnetic levitation technology according to claim 1, characterized in that: The protective bearing (8) is coaxially sleeved on the outside of the cold idler roller shaft (2). A preset safety gap is reserved between the inner ring of the protective bearing (8) and the outer wall of the cold idler roller shaft, and the safety gap is smaller than the working air gap of the radial magnetic levitation bearing.

7. A high-precision active control process method for horizontal centrifugal casting based on magnetic levitation technology, characterized in that: The method includes the following steps: Step 1, Equipment Assembly and Preliminary Preparation: Place the cold mold (1) on the cold mold roller (3) to ensure that the pre-set annular groove of the cold mold shell is in precise surface contact with the roller, check that the assembly status of each component is qualified, and at the same time complete the casting mold pretreatment, raw material melting and refining and cold mold preheating. Step 2: The two axial magnetic levitation bearings (11) of the winding coil generate a balanced bidirectional axial attraction force on the thrust plate (12), so that the winding coil A (14) turns in the four orthogonal directions of X+, X-, Y+, Y-, and realize the start-up magnetic levitation support system of the cold idler shaft. The control system is started through the electrical control cabinet (7) to pass a constant bias current to the winding coil B (17) in the axial magnetic levitation bearing (11), so that the two axial magnetic levitation bearings (11) generate a balanced bidirectional axial attraction force on the thrust plate (12), and the idler shaft is initially suspended in the axial direction at the preset equilibrium position. At the same time, the eight winding coils A (14) of the eight-pole radial magnetic levitation bearing (10) generate radial support force in the four orthogonal directions of X+, X-, Y+, Y-, so that the cold idler shaft is suspended in the radial direction, and the initialization of the non-contact suspension attitude of the cold idler shaft is completed. Step 3: Start the transmission system and detection system: Start the drive motor (6), which drives the cold idler shaft (2), cold idler (3) and cold idler (1) to rotate through the universal coupling (5). At the same time, start the radial speed position sensor (9) and the axial speed position sensor (13) to collect signals in real time. After the signal conditioning unit filters, amplifies, and linearizes the signal, it is fed back to the main control unit. The main control unit adjusts the output torque of the drive motor (6) so that the cold idler (1) reaches the preset stable speed. Step 4: Implement layered casting operation: After the rotation speed of the cold mold (1) stabilizes, inject the outer layer of wear-resistant alloy molten metal and the inner layer of tough material molten metal into the cold mold (1) in sequence. During the casting process, the main control unit continuously receives position and rotation speed detection signals. If radial or axial displacement of the cold mold idler shaft (2) is detected, the excitation current of the corresponding magnetic levitation bearing is immediately dynamically adjusted to push the cold mold idler shaft (2) to reset, ensuring the stable rotation posture of the cold mold. Step 5, solidification, cooling and attitude maintenance: Keep the cold type (1) rotating at a specific speed until the molten metal solidifies naturally, and then undergo forced cooling and natural cooling to room temperature. During the cooling process, the magnetic levitation support and detection system continue to work. Step 6, Post-processing: Turn off the drive motor (6) and the magnetic levitation bearing system, demold, clean and inspect, qualified castings are annealed, and if necessary, quenched and tempered to obtain finished products.

8. The high-precision active control process method for horizontal centrifugal casting based on magnetic levitation technology according to claim 7, characterized in that: In step one, the cold preheating temperature is 200-400℃ and the preheating time is 1-2 hours, and in step three, the fluctuation of the preset stable speed is ≤ ±5r / min.

9. The high-precision active control process method for horizontal centrifugal casting based on magnetic levitation technology according to claim 7, characterized in that: In step four, the pouring temperature of the outer wear-resistant alloy molten metal is 1400–1500℃, the pouring temperature of the inner toughness material molten metal is 1380–1480℃, the pouring speed is 0.5–2 kg / s, and the interval between two pours is 3–10 minutes.

10. The high-precision active control process method for horizontal centrifugal casting based on magnetic levitation technology according to claim 7, characterized in that: In step five, the rotation time of the molten metal during the natural solidification stage is 10-30 minutes, the forced cooling rate is 5-15℃ / min, and the forced cooling endpoint temperature is 200-300℃. In step six, the annealing temperature is 600-700℃, and the annealing time is 2-4 hours.

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