An apparatus and method for rapid cooling of the corners of continuously cast billets.

Abstract

This invention discloses a device and method for rapid cooling of the corners of continuously cast billets. It includes nozzles located at the four corners of the billet, angle gauges, a rotating frame, a rotating shaft, air pipes, water pipes, a transverse frame, a water-air mixing device, a fixed support, a rotary motor, a connecting support, and a movable sleeve. Each nozzle is equipped with an angle gauge. The nozzles are fixed to the rotating frame, and the tail of each nozzle is connected to the water-air mixing device. Air pipes and water pipes are connected to the water-air mixing device. The rotating frame is fixed to the rotating shaft. A fixed support is fixed to the transverse frame, and a rotary motor is mounted on the fixed support. The output shaft of the rotary motor is connected to the rotating shaft as a whole. The transverse frame is fixed to the movable sleeve as a whole via the connecting support. This invention has a simple overall structure, strong applicability, and avoids corner cracks in the cast billet.

Description

Technical Field

[0001] This invention belongs to the field of rapid cooling technology for the corners of continuously cast billets, and specifically relates to a device and method for rapid cooling of the corners of continuously cast billets. Background Technology

[0002] Continuous casting is the core process of transforming molten steel into cast billets. In actual production, due to the increase of alloying elements, the solidification shrinkage and internal microstructure of the steel change, easily leading to quality defects such as surface cracks, corner transverse cracks, surface pits, and subcutaneous inclusions. In particular, corner transverse cracks in Nb-containing steel account for more than 50% of all defects, becoming a major factor restricting the improvement of billet quality. The external factors contributing to the formation of corner transverse cracks mainly include stress factors (including straightening and bending stress, phase transformation stress, thermal stress, and mechanical stress caused by equipment factors), secondary cooling conditions, crystallizer vibration, crystallizer liquid level fluctuations, and the properties of the protective slag. Among these, secondary cooling conditions are the key factor affecting corner transverse cracks in the cast billet. Since there are three brittle temperature zones during the solidification process of molten steel, if the billet is bent or straightened in the brittle zone, transverse cracks will occur. However, if bending or straightening is performed at temperatures above or below this temperature range, transverse cracks can be minimized.

[0003] Since the cooling intensity of the current crystallizer is controlled as a whole, it is impossible to control the temperature of the corner of the billet individually. Therefore, there is an urgent need to develop a device and method for rapid cooling of the corner of the continuously cast billet, so as to rapidly reduce the temperature of the corner of the billet, thereby avoiding the three brittle temperature zones and reducing transverse cracks at the corner of the billet.

[0004] To understand the current technological status of corner quality improvement and rapid cooling in continuously cast billets, a search was conducted on relevant technologies. The search yielded three patents related to corner treatment and crack prevention in continuously cast billets, as detailed below:

[0005] 1. Shanghai Dongzhen Metallurgical Engineering Technology Co., Ltd. has developed an automatic flame cleaning device for the corners of continuously cast billets and its operating method (Cheng Huang, Zhang Yongqiang, Yang Jianpeng. Automatic Flame Cleaning Device for the Corners of Continuously Cast Billets and its Operating Method. China, Invention Patent, CN201210241681.1.2012.10.10.). It consists of a support frame, a trolley track, a cleaning machine trolley, a trolley drive unit, a heat insulation plate, a cleaning trolley, a cleaning trolley track, a trolley drive unit, a cleaning gun, an automatic height adjustment device, a control valve station, and a billet straightening device. The cleaning trolley travels on the trolley track mounted on the support frame, and the lower part of the cleaning machine trolley is equipped with a heat insulation plate. The trolley drive unit provides power for the movement of the cleaning machine trolley. The cleaning trolley track is fixed on the cleaning trolley, and two cleaning trolleys are symmetrically arranged at both ends of the cleaning trolley track. The trolley drive unit drives the cleaning trolleys to move back and forth on the cleaning trolley track. The cleaning gun is mounted on the automatic height adjustment device. The power supply and energy transmission lines on the cleaning trolley are controlled by the control valve station. A slab straightening device is installed on the main cleaning machine trolley to correct the cleaning trajectory of the corners of the continuously cast slabs during the cleaning process. This invention is mainly used for cleaning slabs after corner cracks have occurred; it cannot be used to prevent corner cracks in slabs.

[0006] 2. Shanxi Taigang Stainless Steel Co., Ltd. disclosed a method for inspecting microcracks at the corners of carbon steel continuously cast billets (Zhang Bin, Wang Fuwei, Wang Honghui. A method for inspecting microcracks at the corners of carbon steel continuously cast billets. China, Invention Patent, CN201110147648.8.2011.11.02.), which includes the following steps: (1) sampling; (2) sample cutting; (3) pickling the sample. By cutting a sample strip of a certain shape from the corner of the billet of crack-sensitive steel grade and inspecting it after pickling, the distribution of fine cracks at the corner of the billet can be fed back in a timely and accurate manner. Based on this, the corner defects of the billet in the furnace that produced cracks can be removed by means of flame cleaning or grinding, so as to avoid the billet with corner defects from flowing to the rolling process and producing scrap after rolling. This patent is only used for the physical and chemical inspection and analysis of corner cracks in carbon steel, and cannot fundamentally avoid the occurrence of corner cracks in billets.

[0007] 3. Anhui University of Technology disclosed a method for improving corner cracks and hot-transfer cracks in niobium-containing steel billets using low-voltage pulsed current (Zhu Zhenghai, Wei Li. Method for Improving Corner Cracks and Hot-Transfer Cracks in Niobium-Containing Steel Billets Using Low-Voltage Pulsed Current. China, Invention Patent, CN201210203022.9.2012.10.03.). This invention involves applying a pulsed current to the niobium-containing steel billet before it enters the straightening zone or after it is cut from the continuous casting machine. The pulsed current parameters are: pulse voltage 2–20V, pulse current 30–120A, and pulse frequency 15–40Hz. The niobium-containing steel is a low-carbon steel with ω[C] < 0.25%, where 0.01% ≤ ω[Nb] ≤ 0.40%. This invention alters the microstructure of niobium-containing low-carbon steel billets by applying a low-voltage pulsed current, improving the high-temperature mechanical properties of the billets and effectively reducing corner cracks and hot-feeding (red-feeding) cracks. Furthermore, this method does not affect normal production, requires no changes to existing production processes, does not require the addition of alloying elements, causes no pollution to the billets or equipment, and poses no harm to personnel. It is an environmentally friendly and safe new technology for reducing billet defects. However, this method is only applicable to niobium-containing steel and cannot be applied to the prevention and control of corner cracks in billets of other steel grades.

[0008] In summary, there is a need to invent a device and method for rapid cooling of the corners of continuously cast billets. Summary of the Invention

[0009] The purpose of this invention is to overcome the shortcomings of the above-mentioned background technology and provide a device and method suitable for rapid cooling of the corner of a continuously cast billet.

[0010] The technical solution adopted in this invention is: a device suitable for rapid cooling of the corners of continuously cast billets, comprising nozzles, angle gauges, a rotating frame, a rotating shaft, air pipes, water pipes, a transverse frame, a water-air mixing device, a fixed bracket, a rotary motor, a connecting bracket, and a movable sleeve, all located at the four corners of the continuously cast billet; each nozzle is equipped with an angle gauge, the nozzles are fixed to the rotating frame, the tail of each nozzle is connected to the water-air mixing device, the water-air mixing device is connected to both an air pipe and a water pipe, the rotating frame is fixed to the rotating shaft, the transverse frame is fixed to the fixed bracket, the fixed bracket is equipped with the rotary motor, the output shaft of the rotary motor is connected to the rotating shaft as a whole, and the transverse frame is fixed to the movable sleeve as a whole via the connecting bracket.

[0011] In a further preferred configuration, the outer side of the transverse frame is provided with a transverse drive system, a transverse mechanism, and a fixed connecting rod. One end of the fixed connecting rod is fixed to the guide column, and the other end is fixed to the transverse drive system. One end of the transverse mechanism is connected to the transverse drive system, and the other end is connected to the transverse frame.

[0012] In a further preferred configuration, the lateral movement mechanism is equipped with a displacement sensor.

[0013] In a further preferred configuration, the guide column, along with the lateral drive system, lateral mechanism, and lateral frame, are fixed to the mounting frame of the sector segment via two locking brackets and connecting bolts at both ends.

[0014] In a further preferred configuration, the inner diameter of the movable sleeve is the same as the outer diameter of the guide post.

[0015] In a further preferred configuration, an encoder is mounted on the rotary motor.

[0016] In a further preferred configuration, the water pipe is equipped with both an air pressure and a flow rate regulating valve, and a water pressure and a flow rate regulating valve.

[0017] In a further preferred configuration, the rotating frame is fixed to the rotating shaft by a locking ring.

[0018] A method for a device suitable for rapid cooling of the corner of a continuously cast billet, comprising:

[0019] Step 1: Keep the initial distance between the rotation axes of the two mating nozzles at the top and bottom of the four corners of the continuous casting billet at S, and distribute them symmetrically along the center line of the billet width. In the initial state, nozzles #1 and #3 are horizontally to the right, and nozzles #2 and #4 are horizontally to the left. At this time, the reading of the angle gauge on nozzles #1 and #3 is 0°; the reading of the angle gauge on nozzles #2 and #4 is 180°. At this time, clear the encoder reading of the rotary motor to zero, and also clear the reading of the displacement sensor to zero.

[0020] Step 2: Read the casting width L of the continuous casting billet, and automatically match the spray angle α according to the steel grade and billet width; calculate the distance b that nozzles #1, #2, #3 and #4 need to move towards the center of the continuous casting billet, b = / 2 - H / tanα, where H is the vertical distance from the rotation center of the nozzle to the center line of the thickness of the continuous casting billet; simultaneously start the four transverse drive systems and drive the transverse mechanism and transverse frame to move towards the center of the continuous casting billet, and at the same time, the displacement sensors start counting and record them as c1, c2, c3 and c4 respectively. When c1 = c2 = c3 = c4 = b, the transverse drive system stops moving;

[0021] Step 3: Simultaneously start all four rotary motors, and their respective encoders begin counting. Rotary motor #1 rotates clockwise, and the encoder tracks its rotation angle. It stops rotating when the clockwise rotation angle γ1 = α. At this point, compare the angle α1 measured by the angle meter to 360° - α. If |360° - α1 - α| ≥ θ, where θ is the allowable angle deviation (range 1° - 5°), then angle meter #1 or its encoder is faulty. Stop the machine and check for confirmation. Rotary motor #2 rotates counter-clockwise, and the encoder tracks its rotation angle. It stops rotating when the counter-clockwise rotation angle γ2 = α. At this point, compare the angle α2 measured by the angle meter to 180° + α. If |α1 - 180° - α| ≥ θ, where θ is the allowable angle deviation (range 1° - 5°), then angle meter #2 is faulty. If the angle measuring instrument or encoder is faulty, the machine should be stopped and checked. Specifically, rotary motor #3 rotates counter-clockwise, and the encoder tracks its rotation angle. When the counter-clockwise rotation angle γ3 = α, it stops rotating. At this point, compare the angle α2 of the angle measuring instrument with α. If |α1 - α| ≥ θ, where θ is the allowable angle deviation value (range 1°-5°), then angle measuring instrument #3 or the encoder is faulty and should be stopped and checked. Similarly, rotary motor #4 rotates clockwise, and the encoder tracks its rotation angle. When the clockwise rotation angle γ4 = α, it stops rotating. At this point, compare the angle α1 of the angle measuring instrument with 180° - α. If |α1 - 180° + α| ≥ θ, where θ is the allowable angle deviation value (range 1°-5°), then angle measuring instrument #4 or the encoder is faulty and should be stopped and checked.

[0022] Step 4: When γ1 = γ2 = γ3 = γ4 = α, match the water pressure P of each nozzle according to the steel grade and the width of the billet cross-section. 水 and traffic V 水 air pressure P 气 and traffic V 气 The water pressure and flow rate, as well as the air pressure and flow rate, of each nozzle are adjusted and controlled, and recorded as P1 respectively. 水 V1 水 P1 气 V1 气 P2 水 V2 水 P2 气 V2 气 P3 水 V3 水 P3 气 V3 气 P4 水 V4 水 P4 气 V4 气,When any 1.1P 气 ≤Pn 气 If n takes the value 1, 2, 3, or 4, then the air pressure at nozzle n# is too high; when any value is 1.1P 水 ≤Pn 水 If n takes the value 1, 2, 3, or 4, then the water pressure at nozzle n# is too high; when any value is 0.9P... 气 ≥Pn 气 If n takes the value 1, 2, 3, or 4, then the n# nozzle pressure is too low; when any value is 0.9P... 水 ≥Pn 水 If n takes the value 1, 2, 3, or 4, then the water pressure of nozzle n# is too low; when any one of them is 1.1V 气 ≤Vn 气 If n takes the value 1, 2, 3, or 4, then the gas flow rate of nozzle n# is too high; when any value is 1.1V 水 ≤Vn 水 If n takes the value 1, 2, 3, or 4, then the water flow rate of nozzle n# is too high; when any value is 0.9V 气 ≥Vn 气 If n takes the value 1, 2, 3, or 4, then the gas flow rate of nozzle n# is too low; when any value is 0.9V 水 ≥Vn 水 If n takes the value 1, 2, 3, or 4, then the water flow rate of nozzle n# is too low; this will continue until the casting process is complete.

[0023] Step 5: Turn off the water and gas flow and pressure of each nozzle; simultaneously start the four rotary motors to rotate by an angle α in the opposite direction of Step 3, so that each nozzle returns to its initial state, that is, in the initial state, nozzles #1 and #3 are horizontal to the right, and nozzles #2 and #4 are horizontal to the left. At this time, the reading of the angle gauge on nozzles #1 and #3 is 0°; the reading of the angle gauge on nozzles #2 and #4 is 180°. After the above requirements are met, proceed to Step 6.

[0024] Step 6: Simultaneously start the transverse drive system and drive the transverse mechanism and transverse frame to move away from the center of the continuous casting billet until the initial distance between the rotation axes of the two mating nozzles on the left and right is S and they are symmetrically distributed along the center line of the width of the continuous casting billet, then the process ends.

[0025] This invention features a simple overall structure, low cost, and strong applicability, preventing corner cracks in the cast billet. Through a transverse drive system, transverse mechanism, guide column, and transverse frame, the nozzle can move laterally in the horizontal direction, and a displacement sensor enables precise control of the nozzle position. A rotary motor, rotary shaft, and rotary frame enable nozzle angle rotation, and an encoder mounted on the rotary motor and an angle gauge mounted on the nozzle enable precise control of the rotation angle. The encoder automatically calculates the rotation angle of the rotary motor and compares the calculated angle with the angle gauge value, ensuring the accuracy and reliability of the nozzle rotation angle. By automatically reading the width of the continuously cast billet and the theoretical spray angle of the nozzle, combined with the vertical distance between the nozzle's rotation center and the center line of the continuously cast billet thickness, the required lateral movement distance and rotation angle of the nozzle can be automatically calculated, achieving unmanned control. Each nozzle, through air pressure and flow regulating valves and water pressure and flow regulating valves, enables precise control and proportioning of the energy medium. Furthermore, by comparing the pressure and flow with set values, it automatically determines whether the operation is normal and reliable, achieving self-diagnosis of faults. Attached Figure Description

[0026] Figure 1 This is a front view of the device of the present invention;

[0027] Figure 2 This is a side view of the device of the present invention.

[0028] In the diagram: 1-Continuous casting billet; 2-Nozzle; 3-Angle gauge; 4-Rotating frame; 5-Rotating shaft; 6-Transverse movement drive system; 7-Locking frame; 8-Guide column; 9-Mounting frame; 10-Connecting bolt; 11-Displacement sensor; 12-Air pipe; 13-Water pipe; 14-Transverse movement mechanism; 15-Air pressure and flow regulating valve; 16-Water pressure and flow regulating valve; 17-Transverse movement frame; 18-Water-air mixing device; 19-Fixed bracket; 20-Rotating motor; 21-Encoder; 22-Fixed connecting rod; 23-Connecting bracket; 24-Modible sleeve; 25-Locking ring. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments to facilitate a clear understanding of the present invention, but these descriptions do not constitute a limitation on the present invention.

[0030] Example 1:

[0031] like Figure 1 and Figure 2As shown: A device for rapid cooling of the corner of a continuously cast billet includes a continuous nozzle 2, an angle gauge 3, a rotating frame 4, a rotating shaft 5, a transverse drive system 6, a locking frame 7, a guide column 8, a mounting frame 9, connecting bolts 10, a displacement sensor 11, an air pipe 12, a water pipe 13, a transverse mechanism 14, an air pressure and flow regulating valve 15, a water pressure and flow regulating valve 16, a transverse frame 17, a water-air mixing device 18, a fixed bracket 19, a rotary motor 20, an encoder 21, a fixed connecting rod 22, a connecting bracket 23, a movable sleeve 24, and a locking ring 25.

[0032] To rapidly cool the four corners of the continuously cast billet 1, a nozzle 2 is installed at each corner. Each nozzle 2 is equipped with an angle gauge 3, which can measure and track the tilt angle of the nozzle 2 in real time. The nozzles 2 are fixed to the rotating frame 4, and a water-air mixing device 18 is connected to the tail of each nozzle 2. The main function of the water-air mixing device 18 is to mix water and air. An air pipe 12 and a water pipe 13 are connected to the water-air mixing device 18. An air pressure and flow regulating valve 15 is installed on the water pipe 12, mainly for monitoring and regulating the air pressure and flow rate of the nozzles 2. A water pressure and flow regulating valve 16 is installed on the water pipe 13, mainly for regulating the water pressure and flow rate of the nozzles. 2. The water pressure and flow rate are monitored and adjusted; the rotating frame 4 is fixed to the rotating shaft 5 by the locking ring 25, and a fixed bracket 19 is fixed on the transverse frame 17. A rotating motor 20 is installed on the fixed bracket 19, and the output shaft of the rotating motor 20 is connected to the rotating shaft 5 as a whole. In this way, the rotation of the rotating motor 20 can drive the rotating shaft 5, the rotating frame 4 fixed on the rotating shaft 5, and the nozzle 2 to rotate together; since an encoder 21 is installed behind the rotating motor 20, the rotation angle of the nozzle 2 can be measured and monitored in real time. In the initial state, the nozzle 2 is in a vertically downward state, and its axis is perpendicular to the water during rotation. The angle of the horizontal line is denoted as α. The transverse frame 17 is fixed as a whole to the movable sleeve 24 by the connecting bracket 23. Since the inner diameter of the movable sleeve 24 is the same as the outer diameter of the guide post 8, the transverse frame 17 can move left and right along the guide post 8. A transverse drive system 6, a transverse mechanism 14 and a fixed connecting rod 22 are provided on the outside of the transverse frame 17. One end of the fixed connecting rod 22 is fixed to the guide post 8 and the other end is fixed to the transverse drive system 6. One end of the transverse mechanism 14 is connected to the transverse drive system 6 and the other end is connected to the transverse frame 17. In this way, when the transverse drive system 6 extends or retracts left and right, the transverse frame 17 can be driven by the transverse mechanism 14. The nozzles 2 and water-air mixing device 18 on the frame 17 and the transverse frame 17 move left and right. Moreover, since a displacement sensor 11 is provided on the transverse mechanism 14, the moving distance of the transverse mechanism 14 can be accurately measured and controlled. At both ends of the guide column 8, the guide column 8, the transverse drive system 6, the transverse mechanism 14 and the transverse frame 17 are fixed on the mounting frame 9 of the fan-shaped section by two locking frames 7 and connecting bolts 10, so as to achieve accurate positioning. In the initial positioning process, the initial distance between the rotation axes of the two cooperating nozzles 2 on the left and right is S, and they are symmetrically distributed along the center line of the width of the continuous casting billet 1, which is L.

[0033] Example 2:

[0034] A method for a device suitable for rapid cooling of the corner of a continuously cast billet includes:

[0035] Step 1: After fixing the rapid cooling device for the angle of the continuous casting billet 1 onto the mounting frame 9 of the fan-shaped section using connecting bolts 10 and locking brackets 7, keep the initial distance between the rotation axes of the two mating nozzles 2 at the top and bottom both S, and symmetrically distributed along the center line of the width of the continuous casting billet 1. In the initial state, nozzles 1# and 3# are horizontally to the right, and nozzles 2# and 4# are horizontally to the left. At this time, the reading of the angle gauge 3 on nozzles 1# and 3# is 0°; the reading of the angle gauge 3 on nozzles 2# and 4# is 180°. Then, clear the encoder 21 reading of the rotary motor 20 to zero, and also clear the reading of the displacement sensor 11 to zero, and proceed to step 2.

[0036] Step 2: Read the casting width L of the continuous casting billet 1 from the secondary machine, and automatically match the spray angle α (α is the angle between nozzle #3 and the horizontal line) according to the steel grade and billet width; at this time, calculate the distance b that nozzles #1, #2, #3 and #4 need to move towards the center of the continuous casting billet 1, b=(SL) / 2-H / tanα, H is the vertical distance from the rotation center of nozzle 2 to the thickness center line of the continuous casting billet 1; at the same time, start the four transverse drive systems 6 and drive the transverse mechanism 14 and transverse frame 17 to move towards the center of the continuous casting billet 1. At the same time, the displacement sensor 11 starts counting and records it as c1, c2, c3 and c4 respectively. When c1=c2=c3=c4=b, the transverse drive system 6 stops moving and proceeds to step 3;

[0037] Step 3: Simultaneously start all four rotary motors 20, and their respective encoders 21 begin counting. Rotary motor #1 rotates clockwise, and its rotation angle is tracked by the encoder 21. It stops rotating when the clockwise rotation angle γ1 = α. At this point, compare the angle α1 measured by the angle meter to 360° - α. If |360° - α1 - α| ≥ θ, where θ is the allowable angle deviation value (range 1° - 5°), then angle meter #1 or the encoder is faulty. Stop the machine and check for confirmation. Rotary motor #2 rotates counterclockwise, and its rotation angle is tracked by the encoder 21. It stops rotating when the counterclockwise rotation angle γ2 = α. At this point, compare the angle α2 measured by the angle meter to 180° + α. If |α1 - 180° - α| ≥ θ, where θ is the allowable angle deviation value (range 1° - 5°), then angle meter #2 or the encoder is faulty. Faults were identified, and the machine was stopped for inspection and confirmation. Specifically, rotary motor #3 (20) rotated counter-clockwise, and its rotation angle was tracked by encoder #21. Rotation stopped when the counter-clockwise rotation angle γ3 = α. At this point, the angle α2 of the angle meter was compared to α. If |α1 - α| ≥ θ, where θ is the allowable angle deviation value (range 1°-5°), then angle meter #3 or the encoder was faulty. The machine was stopped for inspection and confirmation. Similarly, rotary motor #4 (20) rotated clockwise, and its rotation angle was tracked by encoder #21. Rotation stopped when the clockwise rotation angle γ4 = α. At this point, the angle α1 of the angle meter was compared to 180° - α. If |α1 - 180° + α| ≥ θ, where θ is the allowable angle deviation value (range 1°-5°), then angle meter #4 or the encoder was faulty. The machine was stopped for inspection and confirmation. When γ1 = γ2 = γ3 = γ4 = α, proceed to step 4.

[0038] Step 4: Match the water pressure P of each nozzle 2 according to the steel grade and the cross-sectional width of the billet. 水 and traffic V 水 air pressure P 气 and traffic V 气 The water pressure and flow rate, as well as the air pressure and flow rate, are regulated and controlled by the air pressure and flow rate regulating valve 15 and the water pressure and flow rate regulating valve 16 for each nozzle 2, and recorded as P1 respectively. 水 V1 水 P1 气 V1 气 P2 水 V2 水 P2 气 V2 气 P3 水 V3 水 P3 气 V3 气 P4水 V4 水 P4 气 V4 气, When any 1.1P 气 ≤Pn 气 If n takes the value 1, 2, 3, or 4, then the air pressure at nozzle n# is too high; when any value is 1.1P 水 ≤Pn 水 If n takes the value 1, 2, 3, or 4, then the water pressure at nozzle n# is too high; when any value is 0.9P... 气 ≥Pn 气 If n takes the value 1, 2, 3, or 4, then the n# nozzle pressure is too low; when any value is 0.9P... 水 ≥Pn 水 If n takes the value 1, 2, 3, or 4, then the water pressure of nozzle n# is too low; when any one of them is 1.1V 气 ≤Vn 气 If n takes the value 1, 2, 3, or 4, then the gas flow rate of nozzle n# is too high; when any value is 1.1V 水 ≤Vn 水 If n takes the value 1, 2, 3, or 4, then the water flow rate of nozzle n# is too high; when any value is 0.9V 气 ≥Vn 气 If n takes the value 1, 2, 3, or 4, then the gas flow rate of nozzle n# is too low; when any value is 0.9V 水 ≥Vn 水 If n takes the value 1, 2, 3, or 4, then the water flow rate of nozzle n# is too low; proceed to step 5 after casting is completed.

[0039] Step 5: Close the flow and pressure of water and gas in each nozzle 2 by using the air pressure and flow regulating valve 15 and the water pressure and flow regulating valve 16; simultaneously start the four rotary motors 20 to rotate by an angle α in the opposite direction to step 3, so that each nozzle 2 returns to its initial state, that is, in the initial state, nozzles 1# and 3# are horizontally to the right, and nozzles 2# and 4# are horizontally to the left. At this time, the reading of the angle gauge 3 on nozzles 1# and 3# is 0°; the reading of the angle gauge 3 on nozzles 2# and 4# is 180°. After achieving the above requirements, proceed to step 6.

[0040] Step 6: Simultaneously start the transverse drive system 6 and drive the transverse mechanism 14 and transverse frame 17 to move away from the center of the continuous casting billet 1 until the initial distance between the rotation axes of the two mating nozzles 2 on the left and right is S and they are symmetrically distributed along the center line of the width of the continuous casting billet 1, then the process ends.

[0041] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. A cooling method for a device suitable for rapid cooling of the corner of a continuously cast billet, characterized in that: The device for rapid cooling of the corners of continuously cast billets includes nozzles (2) at the four corners of the continuously cast billet (1), an angle gauge (3), a rotating frame (4), a rotating shaft (5), an air pipe (12), a water pipe (13), a transverse frame (17), a water-air mixing device (18), a fixed bracket (19), a rotating motor (20), a connecting bracket (23), and a movable sleeve (24); each nozzle (2) is equipped with an angle gauge (3), and the nozzles (2) are fixed on the rotating frame (4). The tail is connected to a water-air mixing device (18), on which air pipe (12) and water pipe (13) are respectively connected. The rotating frame (4) is fixed on the rotating shaft (5). A fixed bracket (19) is fixed on the transverse frame (17). A rotating motor (20) is installed on the fixed bracket (19). The output shaft of the rotating motor (20) is connected to the rotating shaft (5) as a whole. The transverse frame (17) is fixed to the movable sleeve (24) as a whole through the connecting bracket (23). The outer side of the transverse frame (17) is provided with a transverse drive system (6), a transverse mechanism (14) and a fixed connecting rod (22). One end of the fixed connecting rod (22) is fixed to the guide column (8) and the other end is fixed to the transverse drive system (6). One end of the transverse mechanism (14) is connected to the transverse drive system (6) and the other end is connected to the transverse frame (17). An encoder (21) is installed on the rotary motor (20); The cooling method of the device for rapid cooling of the corner of a continuously cast billet includes: Step 1: Keep the initial distance between the rotation axes of the two mating nozzles (2) at the top and bottom of the four corners of the continuous casting billet (1) at S, and distribute them symmetrically along the center line of the width of the continuous casting billet (1). In the initial state, nozzles 1# and 3# (2) are horizontal to the right, and nozzles 2# and 4# (2) are horizontal to the left. At this time, the reading of the angle gauge (3) on nozzles 1# and 3# (2) is 0°; the reading of the angle gauge (3) on nozzles 2# and 4# (2) is 180°. At this time, clear the encoder (21) reading of the rotary motor (20) to zero, and clear the reading of the displacement sensor (11) to zero. Step 2: Read the casting width L of the continuous casting billet (1) and match the spray angle α according to the steel grade and billet width; calculate the distance b that nozzles 1#, 2#, 3# and 4# need to move towards the center of the continuous casting billet (1), b=(SL) / 2-H / tanα, H is the vertical distance between the rotation center of nozzle (2) and the thickness center line of the continuous casting billet (1); at the same time, start the four transverse drive systems (6) and drive the transverse mechanism (14) and transverse frame (17) to move towards the center of the continuous casting billet (1), and at the same time, the displacement sensor (11) starts counting and is recorded as c1, c2, c3 and c4 respectively. When c1=c2=c3=c4=b, the transverse drive system (6) stops moving; Step 3: Simultaneously start the four rotary motors (20), and their respective encoders (21) begin counting; among them, rotary motor #1 (20) rotates clockwise, and the encoder (21) tracks the rotation angle of rotary motor (20). When the rotation angle γ1 of rotary motor (20) is α, it stops rotating; at this time, compare whether the angle α1 of the angle meter (3) is 360°-α. If |360°-α1-α|≥θ, where θ is the allowable deviation value of the angle, the value range is 1°-5°, then If the angle meter (3) or encoder (21) malfunctions, stop the machine and check to confirm; the rotary motor (20) rotates counterclockwise and the encoder (21) tracks the rotation angle of the rotary motor (20). When the rotary motor (20) rotates counterclockwise by an angle γ2=α, it stops rotating; at this time, compare whether the angle α1 of the angle meter (3) is 180°+α. If |α1-180°-α|≥θ, θ is the allowable deviation value of the angle, and the value range is 1°-5°. Then the angle meter (3) If the encoder (21) is faulty, the machine should be stopped and checked. The 3# rotary motor (20) rotates counterclockwise and the encoder (21) tracks the rotation angle of the rotary motor (20). When the rotary motor (20) rotates counterclockwise by an angle γ3=α, it stops rotating. At this time, compare whether the angle α1 of the angle meter (3) is α. If |α1-α|≥θ, where θ is the allowable deviation value of the angle, the value range is 1°-5°. Then the 3# angle meter (3) or the encoder (21) is faulty and the machine should be stopped. After the machine is stopped, check and confirm; among them, the 4# rotary motor (20) rotates clockwise and the encoder (21) tracks the rotation angle of the rotary motor (20). When the rotary motor (20) rotates clockwise by an angle γ4=α, it stops rotating; at this time, compare whether the angle α1 of the angle meter (3) is 180°-α. If |α1-180°+α|≥θ, θ is the allowable deviation value of the angle, and the value range is 1°-5°. Then the 4# angle meter (3) or the encoder (21) has a fault. After stopping the machine, check and confirm. Step 4: When γ1=γ2=γ3=γ4=α, match the water pressure P of each nozzle (2) by the steel grade and the width of the billet cross section. 水 and traffic V 水 air pressure P 气 and traffic V 气 The water pressure and flow rate, as well as the air pressure and flow rate, of each nozzle (2) are adjusted and controlled, and recorded as P1 respectively. 水 V1 水 P1 气 V1 气 P2 水 V2 水 P2 气 V2 气 P3 水 V3 水 P3 气 V3 气 P4 水 V4 水 P4 气 V4 气, When any 1.1P 气 ≤Pn 气 If n takes the value 1, 2, 3, or 4, then the air pressure at nozzle n# is too high; when any value is 1.1P 水 ≤Pn 水 If n takes the value 1, 2, 3, or 4, then the water pressure at nozzle n# is too high; when any value is 0.9P... 气 ≥Pn 气 If n takes the value 1, 2, 3, or 4, then the n# nozzle pressure is too low; when any value is 0.9P... 水 ≥Pn 水 If n takes the value 1, 2, 3, or 4, then the water pressure of nozzle n# is too low; when any one of them is 1.1V 气 ≤Vn 气 If n takes the value 1, 2, 3, or 4, then the gas flow rate of nozzle n# is too high; when any value is 1.1V 水 ≤Vn 水 If n takes the value 1, 2, 3, or 4, then the water flow rate of nozzle n# is too high; when any value is 0.9V 气 ≥Vn 气 If n takes the value 1, 2, 3, or 4, then the gas flow rate of nozzle n# is too low; when any value is 0.9V 水 ≥Vn 水 If n takes the value 1, 2, 3, or 4, then the water flow rate of nozzle n# is too low; this will continue until the casting process is complete. Step 5: Turn off the flow rate and pressure of water and gas in each nozzle (2); at the same time, start the four rotary motors (20) to rotate by an angle α in the opposite direction to step 3, so that each nozzle (2) returns to its initial state, that is, in the initial state, nozzles 1# and 3# (2) are horizontal to the right, and nozzles 2# and 4# (2) are horizontal to the left. At this time, the reading of the angle gauge (3) on nozzles 1# and 3# (2) is 0°; the reading of the angle gauge (3) on nozzles 2# and 4# (2) is 180°. After the above requirements are met, proceed to step 6. Step 6: Simultaneously start the transverse drive system (6) and drive the transverse mechanism (14) and transverse frame (17) to move away from the center of the continuous casting billet (1) until the initial distance between the rotation axes of the two mating nozzles (2) on the left and right is S and they are symmetrically distributed along the center line of the width of the continuous casting billet (1), then the process ends.

2. The cooling method of the device for rapid cooling of the corner of a continuously cast billet according to claim 1, characterized in that: The transverse mechanism (14) is equipped with a displacement sensor (11).

3. The cooling method of the device for rapid cooling of the corner of a continuously cast billet according to claim 1, characterized in that: The guide post (8) is fixed at both ends to the mounting frame (9) of the sector section by two locking brackets (7) and connecting bolts (10), as well as the transverse drive system (6), transverse mechanism (14) and transverse frame (17).

4. The cooling method of the device for rapid cooling of the corner of a continuously cast billet according to claim 1, characterized in that: The inner diameter of the movable sleeve (24) is the same as the outer diameter of the guide post (8).

5. The cooling method of the device for rapid cooling of the corner of a continuously cast billet according to claim 1, characterized in that: The air pipe (12) is equipped with an air pressure and flow regulating valve (15), and the water pipe (13) is equipped with a water pressure and flow regulating valve (16).

6. The cooling method of the device for rapid cooling of the corner of a continuously cast billet according to claim 1, characterized in that: The rotating frame (4) is fixed to the rotating shaft (5) by a locking ring (25).

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