Device and method for controlling immersion depth of water gap

Abstract

A device for controlling the immersion depth of a water gap comprises a detection head, a motor, a pulley and a connecting rod, the detection head is used for detecting liquid level fluctuation, the motor is connected with a rotating shaft, the pulley is fixed to the rotating shaft, a round-link chain is arranged below the pulley and connected with the connecting rod, and the connecting rod is connected with the motor. The connecting rod is fixed on the submersed nozzle of the telescopic crystallizer, and the height of the submersed nozzle of the telescopic crystallizer is controlled through rotation of the rotating shaft. The fluctuation of the liquid level of the crystallizer is detected through the fluctuation detector, the fluctuation condition of the liquid level of the crystallizer is rapidly judged, adjustment is conducted according to technological parameters corresponding to the normal fluctuation condition of the liquid level, and then the height of the submersed nozzle of the telescopic crystallizer is changed through the relation between the technological parameters and the submersed depth. And automation is realized by using a PLC (Programmable Logic Controller) intelligent control system device. The problem that when the liquid level fluctuation is too large, the content of inclusions in the casting blank is too high, and defects are generated is effectively solved.

Description

Technical Field

[0001] Embodiments of the present disclosure generally relate to the field of metallurgy, and more particularly, to an apparatus and method for controlling the immersion depth of a nozzle. Background Art

[0002] With the development of social science and technology and the steel industry, the demand for steel quality in all walks of life is gradually increasing, especially in transportation, construction and national defense construction, which require a large amount of high-purity steel. In order to produce high-quality steel, high-purity ingots are necessary. The continuous casting process is the key to producing high-quality steel, and the crystallizer is one of the most core equipment in the continuous casting equipment. Its work will directly affect the production efficiency and ingot quality of the continuous casting machine. In the process of continuous casting of steel, there are some problems that affect the quality of the billet. During continuous casting, the molten steel enters the crystallizer from the retractable crystallizer immersion nozzle, which will cause the molten steel to fluctuate on the free surface of the crystallizer due to the dispersion of the injection flow. The liquid level fluctuation of the crystallizer affects the production quality of the ingot. When the billet drawing speed is constant, the immersion depth of the immersion nozzle will affect the size of the liquid level fluctuation. When the immersion depth is small, the reflux area of ​​the crystallizer becomes smaller, and the liquid level fluctuation will increase. Excessive liquid level fluctuation will cause the inclusion content of the ingot to exceed the standard, resulting in defects, and in severe cases, it will cause steel leakage accidents. Summary of the invention

[0003] The object of the present invention is to provide a device and method for controlling the immersion depth of a water nozzle, which can improve the free control of the water nozzle of a crystallizer and solve the problem that the immersion depth of the water nozzle of the crystallizer cannot be quickly controlled due to fluctuations in the liquid level of steel.

[0004] The specific technical solutions of this application are as follows:

[0005] A device for controlling the immersion depth of a water outlet comprises a detection head, a motor, a pulley and a connecting rod, wherein the detection head is used to detect liquid level fluctuations, the motor is connected to a rotating shaft, the pulley is fixed on the rotating shaft, a round-ring chain is arranged below the pulley, the round-ring chain is connected to the connecting rod, the connecting rod is fixed on a retractable crystallizer immersion water outlet, and the height of the retractable crystallizer immersion water outlet is controlled by rotating the rotating shaft.

[0006] Furthermore, it also includes a support rod, a mounting plate, a signal processing module, a PC, and a PLC intelligent control system device. The detection head is connected to the support rod and fixed under the mounting plate. There is a signal processing module on the mounting plate, and the signal processing module is connected to the PC. The PLC intelligent control system device is connected to the motor and the PC respectively.

[0007] Furthermore, the retractable crystallizer immersion nozzle is a lower immersion nozzle made into a movable sleeve, and the connecting rod is fixedly connected to the sleeve.

[0008] Furthermore, the liquid level fluctuation is detected by the detection head, transmitted to the signal processing module, and then displayed on the PC. The detection head is placed on the free liquid surface with a safe distance of 50mm from the narrow surface to detect the size of the liquid level fluctuation in real time.

[0009] Furthermore, the connecting rod is fixed on the retractable crystallizer immersion nozzle through a nut.

[0010] Furthermore, the liquid level fluctuation is measured by using a detection head and fed back to the signal processing module, PC and PLC intelligent control system device to control the motor rotation to change the height of the water outlet so that it reaches the normal liquid level fluctuation range.

[0011] Furthermore, the normal range of liquid level fluctuation is ±5 mm, preferably ±3 mm.

[0012] Furthermore, the control method is implemented by the following formula:

[0013]

[0014] Where: d is the moving distance of the submerged nozzle, m; D is the diameter of the submerged nozzle, m; D1 is the width of the crystallizer, m; d1 is the thickness of the crystallizer, m; v1 is the casting speed, m / s; t t＝1s The throwing time is

[0015] 1s; S1 is the outlet area of ​​the water inlet, m 2 ; k is the proportionality coefficient; n is the number of nozzle outlet holes; ρ1 is the density of molten steel, kg / m 3 ; ρ0 is the density of slag, kg / m 3 ; h1 is the height of the submerged nozzle, m; h is the height of the liquid level fluctuation, m; α is the outlet angle of the flow rate; β is the outlet expansion angle of the flow rate; g is the gravitational acceleration, m / s 2 .

[0016] Furthermore, the distance that the submerged nozzle needs to move is obtained by detecting the size of the liquid level fluctuation, and automatic control is completed through a PLC intelligent control system device.

[0017] Advantages and effects of the present invention: The device of the present invention facilitates real-time adjustment of the submerged water outlet through the arrangement of a rotating shaft, a pulley, a round-ring chain and a connecting rod.

[0018] The fluctuation of the liquid level of the crystallizer is detected by a fluctuation detector, the height of the immersion nozzle of the retractable crystallizer is changed, and the automation is realized by a PLC intelligent control system device.

[0019] Based on the algorithm of the present invention, the fluctuation of the liquid level in the crystallizer can be accurately detected and accurately judged, and the moving distance of the submerged water nozzle can be calculated through the formula of the present invention, so that the liquid level fluctuation reaches a balanced range and restores normal fluctuation, thereby reducing the influence of the liquid level fluctuation on the quality of the ingot, and effectively solving the problems such as defects caused by excessive inclusion content in the ingot when the liquid level fluctuation is too large, reducing the losses caused by poor quality of the ingot, and improving the production efficiency of the ingot. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the present invention.

[0021] Among them, 1- ladle, 2- telescopic crystallizer immersion nozzle, 3- crystallizer, 4- detection head, 5- support rod, 6- mounting plate, 7- signal processing module, 8- PC, 9- PLC intelligent control system device, 10- motor, 11- rotating shaft, 12- pulley, 13- round chain, 14- connecting rod, 15- nut DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention is clearly and completely described below. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] The technical solution of the present invention is further explained and illustrated below in conjunction with specific embodiments.

[0024] See also Figure 1 , is a schematic diagram of a control device for detecting liquid level fluctuations to move the immersion depth of a water outlet of the present invention, comprising a detection head 4, a support rod 5, a signal processing module 7, a PC8, a PLC intelligent control system device 9, a motor 10, a pulley 12 and a connecting rod 14. Among them, the detection head 4 is connected to the support rod 5 and fixed under the mounting plate 6. There is a signal processing module 7 on the mounting plate 6, and the signal processing module 7 is connected to the PC8. The PLC intelligent control system device 9 is connected to the motor 10 and the PC8 respectively, the motor 10 is connected to the rotating shaft 11, and the pulley 12 is fixed on the rotating shaft 11. The circular chain 13 is connected to the connecting rod 14, and the connecting rod 14 is fixed to the retractable crystallizer immersion water outlet 2 through a nut 15.

[0025] As a further solution of the present invention: the detection head 4 is connected to the support rod 5 and fixed on the mounting plate 6. The detection head 4 is placed on the free liquid surface with a safe distance of 50 mm from the narrow surface to detect the size of the liquid level fluctuation in real time.

[0026] As a further solution of the present invention: the PLC intelligent control system device 9 is connected to the PC 8 and the motor 10 respectively, and the liquid level fluctuation signal transmitted by the PC 8 is sent to the motor 10.

[0027] As a further solution of the present invention: the circular chain 13 is installed on the pulley 12 of the motor 10, and the height of the retractable crystallizer immersion nozzle 2 can be controlled by pulling and releasing so that the liquid level fluctuation is within a normal range.

[0028] As a further solution of the present invention: the retractable crystallizer immersion nozzle 2 is connected to the connecting rod 14 through a nut 15, and the immersion depth of the retractable crystallizer immersion nozzle can be freely moved according to the size of the liquid level fluctuation detected by the detection head 4.

[0029] Embodiment: This embodiment is applicable to the production of a wide and thick plate continuous casting machine in a certain factory with a cross-sectional size of 1300mm×230mm, and includes the following steps: Figure 1 As shown, the detection head 4 detects the size of the liquid level fluctuation on the free liquid surface, and processes and controls the height of the retractable crystallizer immersion nozzle 2 through the signal processing module 7, PC8 and PLC intelligent control system device 9. In a certain casting series of steel grades, the normal liquid level fluctuation range is generally ±3mm and will not exceed ±5mm. Observe the data measured by the detection head 4 and control the nozzle height to keep it within the normal liquid level fluctuation range. Based on this equipment, the stability and production efficiency of steel production are continuously improved.

[0030] According to the device for detecting liquid level fluctuation in this embodiment, a fluctuation detector is assembled; the detection head 4 is placed on the free liquid surface, with a safe distance of 50 mm from the narrow surface, and the information is fed back to the signal processing module 7 by detecting the size of the liquid level fluctuation, and displayed on the PC 8, and the PLC intelligent control system device 9 controls the motor to move the height of the retractable crystallizer immersion nozzle 2, and then records and observes the changes in the liquid level fluctuation, and observes it every 5 seconds, repeats the observation and recording 8-10 times, and records the changes in the height of the retractable crystallizer immersion nozzle 2 and the liquid level fluctuation each time.

[0031] According to the data of a steel plant, D = 80 mm; D1 = 1300 mm; d1 = 170 mm; v1 = 1.2 m / min; S1 = 3.45 × 10 -3 m 3 ; n = 2; ρ1 = 7000 kg / m 3 ; ρ0=2500kg / m3 ; h1=857mm; h=8mm or 5mm; k=0.1; α=20°; β=5°.

[0032] When h = 8mm,

[0033]

[0034] When h = 5 mm,

[0035]

[0036] The results calculated from the above data show that when h = 8mm, the distance moved by the submerged nozzle is 0.031m, indicating that the liquid level fluctuation is too large at this time, and the submerged nozzle needs to be moved down by 0.031m; when h = 5mm, the distance moved by the submerged nozzle is -0.014m, indicating that the liquid level fluctuation is too small at this time, and the submerged nozzle needs to be moved up by 0.014m. Through this method, the crystallizer liquid level fluctuation can always be kept within the normal liquid level fluctuation range, reducing the impact of liquid level fluctuation on the quality of the ingot, and effectively improving the production efficiency of the ingot.

[0037] Comparative example: Device for controlling the immersion depth of the water outlet.

[0038] It is equivalent to fixing the water inlet or manually adjusting the water inlet immersion depth. During the adjustment process, the response is delayed. Under the same working conditions as in the embodiment, the fluctuation of the crystallizer page exceeds the normal liquid level fluctuation range, which affects the quality of the ingot, consumes labor, and the adjustment is not accurate.

[0039] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted to facilitate understanding of the present invention and are not intended to limit the present invention. Any technician in the field to which the present invention belongs can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A device for controlling the immersion depth of a nozzle, characterized in that: The invention comprises a detection head (4), a motor (10), a pulley (12) and a connecting rod (14), wherein the detection head (4) is used to detect liquid level fluctuations, the motor (10) is connected to a rotating shaft (11), the pulley (12) is fixed on the rotating shaft (11), a round-ring chain (13) is arranged below the pulley (12), the round-ring chain (13) is connected to the connecting rod (14), and the connecting rod (14) is fixed on a telescopic crystallizer immersion nozzle (2) and controls the height of the telescopic crystallizer immersion nozzle (2) by rotating the rotating shaft (11).

2. The device for controlling the immersion depth of a nozzle according to claim 1, characterized in that: The invention also comprises a support rod (5), a mounting plate (6), a signal processing module (7), a PC (8), and a PLC intelligent control system device (9). The detection head (4) is connected to the support rod (5) and fixed under the mounting plate (6). A signal processing module (7) is provided on the mounting plate (6). The signal processing module (7) is connected to the PC (8). The PLC intelligent control system device (9) is connected to the motor (10) and the PC (8) respectively.

3. The device for controlling the immersion depth of a water outlet according to claim 1, characterized in that: The retractable crystallizer submerged water inlet (2) is a lower submerged water inlet made into a movable sleeve, and the connecting rod (14) is fixedly connected to the sleeve.

4. The device for controlling the immersion depth of a water outlet according to claim 2, characterized in that: The liquid level fluctuation is detected by the detection head (4), transmitted to the signal processing module (7), and then displayed on the PC (8). The detection head (4) is placed on the free liquid surface with a safe distance of 50 mm from the narrow surface to detect the size of the liquid level fluctuation in real time.

5. The device for controlling the immersion depth of a water outlet according to claim 2, characterized in that: The connecting rod (14) is fixed on the retractable crystallizer submerged water outlet via a nut (15).

6. A method for controlling the immersion depth of a nozzle by means of the device according to claims 1 to 5, characterized in that: The following steps are involved: The liquid level fluctuation is measured by using a detection head (4), and the result is fed back to a signal processing module (7), a PC (8) and a PLC intelligent control system device (9), so as to control a motor (10) to rotate and change the height of the water outlet so as to reach a normal liquid level fluctuation range.

7. The method for controlling the immersion depth of a nozzle as claimed in claim 6, characterized in that: The normal liquid level fluctuation range is ±5 mm, preferably ±3 mm.

8. The method for controlling the immersion depth of a nozzle as claimed in claims 6-7, characterized in that: The control method is implemented by the following formula: Where: d is the moving distance of the submerged nozzle, m; D is the diameter of the submerged nozzle, m; D1 is the width of the crystallizer, m; d1 is the thickness of the crystallizer, m; v1 is the casting speed, m / s; t t＝1s The casting time is 1s; S1 is the outlet area of ​​the water nozzle, m 2 ; k is the proportionality coefficient; n is the number of nozzle outlet holes; ρ1 is the density of molten steel, kg / m 3 ; ρ0 is the density of slag, kg / m 3 ; h1 is the height of the submerged nozzle, m; h is the height of the liquid level fluctuation, m; α is the outlet angle of the flow rate; β is the outlet expansion angle of the flow rate; g is the gravitational acceleration, m / s 2 .

9. The method for controlling the immersion depth of a nozzle according to claim 8, characterized in that: The distance that the submerged nozzle needs to move is obtained by detecting the size of the liquid surface fluctuation, and automatic control is completed through the PLC intelligent control system device (9).

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