Cooling system and cooling method for preventing steel strip from being supercooled

Abstract

The invention discloses a cooling system and a cooling method for preventing a steel belt from being supercooled, belongs to the technical field of metal processing, and aims to solve the problem of supercooling during aerial fog cooling. The cooling system for preventing the steel belt from being supercooled comprises a roller way (1), a high-temperature metal detector (2), an aerial fog cooling device (3), a water film thickness detector (4), an air injection device (5) and a control unit, the high-temperature metal detector (2), the aerial fog cooling device (3), the water film thickness detector (4) and the air injection device (5) are sequentially arranged in the conveying direction of the roller way (1). According to the cooling system and the cooling method for preventing the steel strip from being supercooled, the cooling capacity of aerial fog cooling can be flexibly adjusted, water sprayed by the aerial fog nozzles is prevented from being gathered on the surface of a steel plate to form a water film, the supercooling phenomenon on the surface of the steel strip is prevented, and diversified cooling requirements are met.

Description

Technical Field

[0001] The invention relates to the technical field of metal processing, in particular to a cooling system for preventing a steel strip from being overcooled, and also to a cooling method for preventing a steel strip from being overcooled. Background Art

[0002] Aerosol cooling is also called air-water spray cooling. It uses the energy of compressed air to atomize water droplets and spray them at high speed onto the surface of high-temperature metal. The diameter of water droplets during aerosol cooling is about 20μm-60μm, which is only 1 / 10 of that of water spray cooling. This increases the surface area of ​​water droplets, increases the coverage area of ​​the jet, and allows the high-temperature metal surface to be evenly cooled. Aerosol cooling was used in the metallurgical industry for secondary cooling of continuous casting billets in the early days. It is now widely used in cooling scenarios for hot processing and heat treatment of metal materials in order to obtain better and more uniform surface quality and physical and chemical properties. In the double-roll thin strip cooling stage, aerosol cooling is used to cool the thin strip. When aerosol cooling is used for cooling in actual production, overcooling will occur between the two nozzles. Summary of the invention

[0003] In order to solve the problem of overcooling caused by the above-mentioned aerosol cooling, the present invention provides a cooling system and a cooling method for preventing overcooling of the steel strip. The cooling system and the cooling method for preventing overcooling of the steel strip can flexibly adjust the cooling capacity of the aerosol cooling, prevent the water sprayed from the aerosol nozzle from gathering on the surface of the steel plate to form a water film, prevent the surface of the steel strip from being overcooled, and meet diverse cooling needs.

[0004] The technical solution adopted by the embodiment of the present invention to solve the technical problem is:

[0005] A cooling system for preventing overcooling of a steel strip comprises: a roller, a high-temperature metal detector, an aerosol cooling device, a water film thickness detector, an air jet device and a control unit. The high-temperature metal detector, the aerosol cooling device, the water film thickness detector and the air jet device are arranged in sequence along the transmission direction of the roller, the high-temperature metal detector, the aerosol cooling device, the water film thickness detector and the air jet device are all connected to the control unit, the high-temperature metal detector can detect the head or tail of the steel strip, the aerosol cooling device can spray aerosol onto the steel strip, the water film thickness detector can detect the thickness of the water film on the steel strip, the air jet device can spray gas onto the steel strip and blow away the water film on the steel strip, and the control unit can control the operation of the cooling system for preventing overcooling of the steel strip.

[0006] A cooling method for preventing a steel strip from being overcooled, the cooling method for preventing a steel strip from being overcooled adopts the above-mentioned cooling system for preventing a steel strip from being overcooled, and the cooling method for preventing a steel strip from being overcooled comprises the following steps in sequence:

[0007] Step 1, establishing an air-water pressure range model and a water film automatic jet model;

[0008] The spray water pressure and spray air pressure of the aerosol cooling device are adjusted multiple times. The spray water pressure of the aerosol cooling device ranges from P W To P Wmax The spray pressure range of the aerosol cooling device is P A -P Amax , observe and record the morphology of the aerosol sprayed by the aerosol cooling device under different spray water pressures and different spray air pressures, and form an air-water pressure range model;

[0009] P W is the minimum spray water pressure of the minimum aerosol cooling device, P Wmax is the maximum spray water pressure of the minimum aerosol cooling device, P A is the minimum injection pressure of the minimum aerosol cooling device, P Amax The maximum injection pressure of the smallest aerosol cooling device;

[0010] According to the form of the aerosol sprayed by the aerosol cooling device under different spray water pressures and different spray air pressures, and the thickness of the water film remaining on the steel strip, the spray air pressure of the jet device is adjusted so that the gas sprayed by the jet device completely blows away the water film on the steel strip. The air pressure when the gas sprayed by the jet device completely blows away the water film on the steel strip is the blowing air pressure P. j Observe and record the water film thickness and the blowing air pressure P j The corresponding relationship forms a water film automatic jet model, and the range of the water film thickness is L min -L max ;

[0011] L min is the minimum value of the residual water film thickness on the steel strip, L max is the maximum value of the thickness of the water film remaining on the steel strip;

[0012] Step 2, the control unit controls the aerosol cooling device to spray aerosol toward the steel strip according to the vertical air-water pressure range model, and the control unit controls the aerosol cooling device to spray gas toward the steel strip and blow away the water film on the steel strip according to the water film automatic jet model.

[0013] The beneficial effects of the embodiments of the present invention are:

[0014] 1. The present invention can effectively prevent the water film from affecting the cooling of the steel plate.

[0015] 2. The present invention can realize continuous production of steel strips of different widths by quickly replacing the nozzles on the spray rack. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings in the specification, which constitute a part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0017] Figure 1 It is a schematic top view of the cooling system for preventing overcooling of the steel strip according to the present invention.

[0018] Figure 2 It is a left schematic view of the cooling system for preventing overcooling of the steel strip according to the present invention.

[0019] Figure 3 It is a connection diagram of a first aerosol nozzle, a first cooling water supply pipeline and a first compressed air supply pipeline.

[0020] Figure 4 It is a connection diagram of the jet port and the second compressed air supply line.

[0021] Figure 5 It is a schematic diagram showing that a plurality of first aerosol nozzles are arranged in a centrally symmetrical manner and face each other.

[0022] Figure 6 It is a schematic diagram of a plurality of first aerosol nozzles arranged in a centrally symmetrical manner and in the same direction.

[0023] Figure 7 Schematic diagram of the head of the first aerosol nozzle.

[0024] Figure 8 Schematic diagram of the tail of the first aerosol nozzle.

[0025] The following are the descriptions of the reference numerals:

[0026] 1. Roller; 2. High temperature metal detector; 3. Air mist cooling device; 4. Water film thickness detector; 5. Jet device; 6. Steel strip; 7. Lower nozzle;

[0027] 31. First spray rack; 32. First cooling water supply pipeline; 33. First compressed air supply pipeline; 34. Second spray rack;

[0028] 51. jet nozzle bracket; 52. second compressed air supply pipeline;

[0029] 311, first aerosol nozzle;

[0030] 321. Cooling water switch valve; 322. Water pressure regulating valve;

[0031] 331. First compressed air switch valve; 332. First air pressure regulating valve;

[0032] 341, second aerosol nozzle;

[0033] 511. Jet orifice; 512. Rotary bracket;

[0034] 521. Second compressed air switch valve; 522. Second pneumatic pressure regulating valve. Detailed implementation manners

[0035] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0036] For the convenience of understanding and description, the following description of the present invention adopts an absolute positional relationship. Without special instructions, the orientation word "up" means the direction perpendicular to the Figure 1 paper surface in and pointing outside the paper surface, the orientation word "down" means the direction perpendicular to the Figure 1 paper surface in and pointing inside the paper surface, "left" means the Figure 1 left side direction in, the orientation word "right" means the Figure 1 right side direction in, "front" means the Figure 1 upper side direction in, the orientation word "rear" means the Figure 1 lower side direction in. The present invention is described from the observation perspective of the reader or user, but the above orientation words should not be understood or interpreted as limiting the protection scope of the present invention. Regarding the dimensions and angles of the components therein, those skilled in the art can specifically determine them according to actual needs or through limited experiments.

[0037] As Figure 1 to Figure 2 shown, a cooling system for preventing a steel strip from being overcooled according to an embodiment of the present invention includes: a roller table 1, a high-temperature metal detector 2, an aerosol cooling device 3, a water film thickness detector 4, a jetting device 5, and a control unit. The high-temperature metal detector 2, the aerosol cooling device 3, the water film thickness detector 4, and the jetting device 5 are all connected to the control unit. The high-temperature metal detector 2, the aerosol cooling device 3, the water film thickness detector 4, and the jetting device 5 are arranged in sequence along the transmission direction A of the roller table 1. The high-temperature metal detector 2 can detect the head or tail of the steel strip 6. The aerosol cooling device 3 can spray aerosol onto the upper surface of the steel strip 6. The water film thickness detector 4 can detect the water film thickness on the upper surface of the steel strip 6. The jetting device 5 can spray gas onto the upper surface of the steel strip 6 and blow away the water film on the steel strip 6. The control unit can control the operation of the cooling system for preventing the steel strip from being overcooled.

[0038] As Figure 3 to Figure 4As shown, the aerosol cooling device 3 comprises a first spray rack 31, a first cooling water supply pipeline 32 and a first compressed air supply pipeline 33. The first spray rack 31 is a horizontal frame structure. The first spray rack 31 is used to install a first aerosol nozzle 311. A plurality of first aerosol nozzles 311 are arranged on the first spray rack 31. The first cooling water supply pipeline 32 and the first compressed air supply pipeline 33 are both connected to the first aerosol nozzle 311. The first cooling water supply pipeline 32 can deliver cooling water to the first aerosol nozzle 311. The first compressed air supply pipeline 33 can deliver compressed air to the first aerosol nozzle 311. The cooling water supply pipeline 32 is provided with a plurality of first aerosol nozzles 311. There are cooling water switch valve 321 and water pressure regulating valve 322, and the first compressed air switch valve 331 and the first air pressure regulating valve 332 are arranged on the first compressed air supply pipeline 33; the jet device 5 contains a jet port bracket 51 and a second compressed air supply pipeline 52, a plurality of jet ports 511 are arranged on the jet port bracket 51, the jet port bracket 51 is used to install the jet ports 511, the second compressed air supply pipeline 52 is connected to the jet ports 511, the second compressed air supply pipeline 52 can transport and supply compressed air to the jet ports 511, and the second compressed air supply pipeline 52 is provided with a second compressed air switch valve 521 and a second air pressure regulating valve 522.

[0039] The plurality of first aerosol nozzles 311 are arranged in rows and columns, the row direction of the row and column arrangement is perpendicular to the conveying direction of the roller 1, and the column direction of the row and column arrangement is parallel to the conveying direction of the roller 1, for example, the row direction is the left-right direction, and the column direction is the front-back direction, and the aerosol cooling device 3 contains a plurality of aerosol nozzle rows or aerosol nozzle columns. An aerosol nozzle row contains a plurality of first aerosol nozzles 311, and the plurality of first aerosol nozzles 311 in an aerosol nozzle row are arranged symmetrically at 5° to 15° relative to each other or symmetrically at 5° to 15° in the same direction. The plurality of air jets 511 are arranged at intervals in a horizontal direction perpendicular to the conveying direction A of the roller 1, for example, the plurality of air jets 511 are arranged at intervals in the left-right direction.

[0040] like Figure 5 As shown, the multiple first aerosol nozzles 311 in an aerosol nozzle row are arranged in a centrally symmetrical manner at an angle of 5° to 15°, which means that the spray outlets of the first aerosol nozzles 311 are flat (i.e., in a long strip shape), the length direction of the spray outlet of the first aerosol nozzle 311 in the center of an aerosol nozzle row is parallel to the left-right direction, the length direction of the spray outlet of the first aerosol nozzle 311 on the left side of an aerosol nozzle row and the length direction of the spray outlet of the first aerosol nozzle 311 on the right side of an aerosol nozzle row are mirror images of each other, and the angle α between the length direction of the spray outlet of the first aerosol nozzle 311 on the right side of an aerosol nozzle row and the left-right direction is 5° to 15°.

[0041] like Figure 6As shown, the multiple first aerosol nozzles 311 in an aerosol nozzle row are arranged in a centrally symmetrical manner at 5° to 15° in the same direction, which means that the spray outlets of the first aerosol nozzles 311 are flat (i.e., in the shape of long strips), and the angle α between the length direction of the spray outlet of each first aerosol nozzle 311 in an aerosol nozzle row and the left-right direction is 5° to 15°.

[0042] The spray direction of the first aerosol nozzle 311 is downward, and the spray direction of the air jet 511 is also downward. When the number of the first aerosol nozzles 311 in an aerosol nozzle row is even, the multiple first aerosol nozzles 311 are arranged in the same direction at 5° to 15° in a central symmetric manner; when the number of the first aerosol nozzles 311 in an aerosol nozzle row is odd, the multiple first aerosol nozzles 311 are arranged in the same direction at 5° to 15° in a central symmetric manner.

[0043] When multiple first aerosol nozzles 311 are arranged centrally and symmetrically at an angle of 5° to 15° toward each other, the spray direction of the jet port 511 is perpendicular to the upper surface of the steel strip 6; when multiple first aerosol nozzles 311 are arranged centrally and symmetrically at an angle of 5° to 15° toward each other, the jet port 511 is biased toward the aerosol cooling device 3, and the angle between the spray direction of the jet port 511 and the upper surface of the steel strip 6 can be 60° to 70°.

[0044] The first spray rack 31 and the jet nozzle bracket 51 can both be raised and lowered, that is, the first aerosol nozzle 311 and the jet nozzle 511 can both be raised and lowered, and the distance between the first aerosol nozzle 311 and the jet nozzle 511 and the roller 1 can be adjusted. The jet nozzle bracket 51 contains a rotating bracket 512, and the jet nozzle 511 is connected to the rotating bracket 512. The rotating bracket 512 can adjust the angle between the spray direction of the jet nozzle 511 and the upper surface of the steel strip 6, that is, the rotating bracket 512 can rotate clockwise and counterclockwise to adjust the spray direction of the jet nozzle 511. In addition, a lower nozzle 7 is provided below the roller 1, and the spray direction of the lower nozzle 7 is upward, and the lower nozzle 7 can also spray aerosol.

[0045] like Figure 1 to Figure 2 As shown, in order to cope with the cooling of steel strips of different widths, spray racks are arranged on both sides of the steel strip, and the spray racks on each side are equipped with aerosol nozzles of different specifications to cope with different cooling scenarios. When the aerosol nozzles on the spray rack on one side perform cooling operations, the spray rack on the other side will be lowered to the outside and the nozzles will be replaced when necessary. That is, the aerosol cooling device 3 also includes a second spray rack 34, a second cooling water supply pipeline, and a third compressed air supply pipeline.

[0046] The second spray rack 34 and the first spray rack 31 have basically the same structure, and the second spray rack 34 and the first spray rack 31 can be used interchangeably. A plurality of second aerosol nozzles 341 are arranged on the second spray rack 34, and the second cooling water supply pipeline and the third compressed air supply pipeline are both connected to the second aerosol nozzles 341. The second cooling water supply pipeline can deliver cooling water to the second aerosol nozzles, and the second compressed air supply pipeline can deliver compressed air to the second aerosol nozzles. The second spray rack 34 and the first spray rack 31 can both move in a direction perpendicular to the transmission direction of the roller 1, that is, the second spray rack 34 and the first spray rack 31 can both move left and right and up and down.

[0047] When the first spray rack 31 is located directly above the roller 1, the second spray rack 34 leaves the top of the roller 1, the first spray rack 31 is in working state, and the second spray rack 34 is in waiting state; when the second spray rack 34 is located directly above the roller 1, the first spray rack 31 leaves the top of the roller 1, the first spray rack 31 is in waiting state, and the second spray rack 34 is in working state.

[0048] like Figure 7 As shown, in order to meet the cooling requirements of steel strips of different widths, the cooling system for preventing the steel strip from being overcooled is also provided with a matching aerosol nozzle (i.e., a first aerosol nozzle 311 and a second aerosol nozzle 341), which is characterized in that the nozzle outlet is a flat arc outlet, and the nozzle outlet of the aerosol nozzle is an integrally formed copper casting. When the width of the steel plate increases, the nozzle outlet width L is selected. P The smaller it is, the larger the spray area a single nozzle can cover.

[0049] like Figure 8 As shown, in order to quickly respond to the cooling process of steel plates of different widths, the system described in the present invention also has a matching quick-release nozzle (i.e., a first aerosol nozzle 311 and a second aerosol nozzle 341), which is characterized in that a quick-release thread is provided at the tail of the nozzle to ensure that the corresponding nozzle can be quickly replaced on either side of the spray rack within the time of adjusting the flow distributor in the front.

[0050] A cooling method for preventing the steel strip from being overcooled is introduced below. The cooling method for preventing the steel strip from being overcooled adopts the above-mentioned cooling system for preventing the steel strip from being overcooled. The cooling method for preventing the steel strip from being overcooled comprises the following steps in sequence:

[0051] Step 1, establishing an air-water pressure range model and a water film automatic jet model;

[0052] The spray water pressure and spray air pressure of the aerosol cooling device 3 are adjusted multiple times. The spray water pressure of the aerosol cooling device 3 is within the range of P W To P Wmax The spray pressure of the aerosol cooling device 3 is in the range of P A-P Amax , (the control unit alone or in cooperation with the operator) observe and record the forms of the aerosol sprayed by the aerosol cooling device 3 under different spray water pressures and different spray air pressures to form an air-water pressure range model;

[0053] P W is the minimum spray water pressure of the minimum aerosol cooling device 3, P Wmax is the maximum spray water pressure of the minimum aerosol cooling device 3, P A is the minimum injection pressure of the minimum aerosol cooling device 3, P Amax is the maximum injection pressure of the minimum aerosol cooling device 3;

[0054] The specific steps are: first determine the water mist shape required for aerosol cooling, adjust the water pressure range and air pressure range P W -P Wmax , P A -P Amax , the air pressure needs to be adjusted from the minimum pressure to the maximum pressure n times, and the water pressure needs to be adjusted from the minimum pressure to the maximum pressure m times. Open the water pressure valve and the air pressure valve to adjust the initial water pressure and air pressure P W and P A At this time, we start to pay attention to the shape of the aerosol and gradually increase the air pressure. After n times of adjusting the air pressure from P A Increase to P Amax At this time, the water pressure can be obtained as P W Similarly, adjust the water pressure m times until it increases to P Wmax , then we can get the water pressure P W -P Wmax The air pressure range corresponding to each water pressure in the range forms an air-water pressure range model;

[0055] According to the form of the aerosol sprayed by the aerosol cooling device 3 under different spray water pressures and different spray air pressures, and the thickness of the water film remaining on the steel strip 6, the spray air pressure of the jet device 5 is adjusted so that the gas sprayed by the jet device 5 completely blows away the water film on the steel strip 6. The air pressure when the gas sprayed by the jet device 5 completely blows away the water film on the steel strip 6 is the blowing air pressure P j , (control unit alone or in cooperation with operator) observe and record the water film thickness and the blowing air pressure P j For example, the water film thickness on the steel strip 6 is L j The blowing pressure is P j ;

[0056] L min ≤L j ≤L max , L min is the minimum value of the residual water film thickness on the steel strip 6, Lmax is the maximum value of the water film thickness remaining on the steel strip 6;

[0057] The specific steps are: determine the shape of water mist under various pressures according to the air-water pressure model, and detect the thickness L of the water film remaining on the steel strip at this time, open the jet valve to adjust the jet pressure P j Until the water film is blown away. Adjust the air and water pressure, detect the thickness of the water film, and obtain the water film thickness range as L min -L max , according to the thickness of the water film, different jet pressures P are obtained j , based on which a water film automatic jet model is constructed.

[0058] Step 2, the control unit controls the aerosol cooling device 3 to spray aerosol toward the steel strip 6 according to the vertical air-water pressure range model, and the control unit controls the jet device 5 to spray gas toward the steel strip 6 and blow away the water film on the steel strip 6 according to the water film automatic jet model. If the cooling capacity needs to be adjusted, the cooling control method is started based on the established air-water pressure range model.

[0059] In step 2, when the high-temperature metal detector 2 detects the head of the steel strip 6 (temperature suddenly rises), the control unit first controls the first compressed air switch valve 331 to open, the control unit secondly controls the cooling water switch valve 321 to open, and the control unit again controls the second compressed air switch valve 521 to open; for example, the high-temperature metal detector detects the high-temperature steel strip time t 1 Afterwards, the system sends a command to the second compressed air switch valve 521, the jet valve opens, and the jet port 511 located behind the aerosol nozzle sprays air to disperse the water film on the steel strip.

[0060] When the high-temperature metal detector 2 detects the tail of the steel strip 6 (the temperature suddenly drops and there is no high-temperature object in the detection area), the control unit first controls the cooling water switch valve 321 to close, and then controls the first compressed air switch valve 331 to close, and then controls the second compressed air switch valve 521 to close.

[0061] In step 2, as a remedial measure to prevent the aerosol cooling system and the water film jet system from being properly executed, when the temperature detector downstream of the cooling system for preventing the steel strip from being overcooled detects that the temperature of the steel strip 6 does not meet the standard, the control unit controls the first spray rack 31 to lower its height. After the jet device 5 sprays gas to the steel strip 6, the water film thickness on the steel strip 6 is still higher than L min When the water film thickness detector 4 detects that the water film thickness on the steel strip 6 is less than L, the control unit controls the jet nozzle bracket 51 to lower its height. Preferably, the jet nozzle behind the aerosol nozzle is not opened every time it works. min When , the system determines that the water film is not sufficient to affect the temperature of the steel plate, and the jet device 5 is not started.

[0062] The following introduces the actual use of cooling systems and cooling methods to prevent overcooling of the steel strip.

[0063] Example 1: At the beginning of production, the aerosol control system is turned on, and the high-temperature metal detector located at the front starts working. When the detector detects a high-temperature area, the high-temperature metal detector sends a signal to the control system, and the control system sends a start command to the corresponding compressed air pneumatic valve, at which time the compressed air pneumatic valve starts; then the control system sends a command to the cooling water solenoid valve, and the nozzle located above the steel strip is arranged at 10° in the same direction and starts to spray aerosol.

[0064] After the high-temperature metal detector detects the high-temperature steel strip for 2 seconds, the system sends a command to the jet valve, the jet valve opens, and the jet port located behind the aerosol nozzle sprays air to blow away the water film on the steel strip, and the angle between the jet port and the steel strip is 70°.

[0065] When the rear temperature detector detects that the temperature of the steel strip does not meet the standard, the system sends a signal to the spray rack lifting control unit, and the system lowers the height of the spray rack; when the jet nozzle is opened, if the water film thickness is still 10mm higher than the lowest point, the system sends a signal to the jet nozzle bracket lifting system to lower the jet nozzle bracket height;

[0066] At the end of production, the high temperature detector detects that the tail of the high temperature steel strip leaves the area, and there is no high temperature object in the detection area. The detector sends a signal to the system. After the system determines that it is finished, it outputs a signal to the cooling water solenoid valve to turn off the cooling water. After the cooling water is turned off, the signal is sent to the system, and in the same way, the signal is output to the pneumatic valve to close the compressed air channel. Finally, the system outputs a signal to close the jet valve;

[0067] After the system has completed several coolings, the width of the production steel strip needs to be adjusted. After the layout conditions of the flow distributor, side sealing plate, nozzle and other devices are updated offline, the width of the steel strip changes. After one side of the spray rack is lifted, the spray rack on the other side is lowered to continue cooling the subsequent steel strip after 1 minute.

[0068] When the spray rack on one side starts working, the spray rack on the other side is idle. At this time, the nozzle can be replaced by the rotating head above the nozzle. Repeating the process of lifting and lowering the two spray racks and changing the nozzles can cope with the cooling process of steel plates of various widths.

[0069] Example 2: When production starts, the aerosol control system is turned on, and the high-temperature metal detector located at the front starts working. When the detector detects a high-temperature area, the high-temperature metal detector sends a signal to the control system, and the control system sends a start command to the corresponding compressed air pneumatic valve, at which time the compressed air pneumatic valve starts; then the control system sends a command to the cooling water solenoid valve, and the nozzles located above the steel strip are arranged at 5° toward each other and start spraying aerosol.

[0070] After the high-temperature metal detector detects the high-temperature steel strip for 5 seconds, the system sends a command to the jet valve, the jet valve opens, and the jet port located behind the aerosol nozzle sprays air to disperse the water film on the steel strip, and the rotating bracket 512 is adjusted so that the angle between the jet port and the steel strip is 90°.

[0071] When the rear temperature detector detects that the temperature of the steel strip does not meet the standard, the system sends a signal to the spray rack lifting control unit, and the system lowers the height of the spray rack; when the jet nozzle is opened, if the water film thickness is still 5mm higher than the lowest point, the system sends a signal to the jet nozzle bracket lifting system to lower the jet nozzle bracket height;

[0072] At the end of production, the high temperature detector detects that the tail of the high temperature steel strip leaves the area, and there is no high temperature object in the detection area. The detector sends a signal to the system. After the system determines that it is finished, it outputs a signal to the cooling water solenoid valve to turn off the cooling water. After the cooling water is turned off, the signal is sent to the system, and in the same way, the signal is output to the pneumatic valve to close the compressed air channel. Finally, the system outputs a signal to close the jet valve;

[0073] After the system has completed several coolings, the width of the production steel strip needs to be adjusted. After the layout conditions of the flow distributor, side sealing plate, nozzle and other devices are updated offline, the width of the steel strip changes. After 2 minutes of the spray rack on one side being lifted, the spray rack on the other side is lowered to continue cooling the subsequent steel strip.

[0074] When the spray rack on one side starts working, the spray rack on the other side is idle. At this time, the nozzle can be replaced by the rotating head above the nozzle. Repeating the process of lifting and lowering the two spray racks and changing the nozzles can cope with the cooling process of steel plates of various widths.

[0075] The above is only a specific embodiment of the present invention, and cannot be used to limit the scope of the invention. Therefore, the replacement of equivalent components, or equivalent changes and modifications made according to the protection scope of the present invention should still fall within the scope of the present invention. In addition, the technical features of the present invention can be freely combined with each other, with technical features and technical solutions, with technical solutions and embodiments.

Claims

1. A cooling system for preventing overcooling of a steel strip, characterized in that: The cooling system for preventing the steel strip from being overcooled comprises: a roller (1), a high-temperature metal detector (2), an aerosol cooling device (3), a water film thickness detector (4), an air jet device (5) and a control unit. The high-temperature metal detector (2), the aerosol cooling device (3), the water film thickness detector (4) and the air jet device (5) are arranged in sequence along the transmission direction of the roller (1). The high-temperature metal detector (2), the aerosol cooling device (3), the water film thickness detector (4) and the air jet device (5) are all connected to the control unit. The high-temperature metal detector (2) can detect the head or tail of the steel strip (6). The aerosol cooling device (3) can spray aerosol onto the steel strip (6). The water film thickness detector (4) can detect the thickness of the water film on the steel strip (6). The air jet device (5) can spray gas onto the steel strip (6) and blow away the water film on the steel strip (6). The control unit can control the operation of the cooling system for preventing the steel strip from being overcooled.

2. The cooling system for preventing overcooling of a steel strip according to claim 1, characterized in that: The aerosol cooling device (3) comprises a first spray rack (31), a first cooling water supply pipeline (32) and a first compressed air supply pipeline (33); a plurality of first aerosol nozzles (311) are arranged on the first spray rack (31); the first cooling water supply pipeline (32) and the first compressed air supply pipeline (33) are both connected to the first aerosol nozzles (311); a cooling water switch valve (321) and a water pressure regulating valve (322) are arranged on the cooling water supply pipeline (32); and the first compressed air supply pipeline (33) is connected to the first aerosol nozzles (311). The pipeline (33) is provided with a first compressed air switch valve (331) and a first air pressure regulating valve (332); the jet device (5) comprises a jet port bracket (51) and a second compressed air supply pipeline (52); a plurality of jet ports (511) are provided on the jet port bracket (51); the second compressed air supply pipeline (52) is connected to the jet ports (511); and a second compressed air switch valve (521) and a second air pressure regulating valve (522) are provided on the second compressed air supply pipeline (52).

3. The cooling system for preventing overcooling of a steel strip according to claim 2, characterized in that: The plurality of first aerosol nozzles (311) are arranged in rows and columns, the row direction of the row and column arrangement is perpendicular to the transmission direction of the roller (1), the column direction of the row and column arrangement is parallel to the transmission direction of the roller (1), an aerosol nozzle row contains a plurality of first aerosol nozzles (311), and the plurality of first aerosol nozzles (311) in an aerosol nozzle row are arranged centrally symmetrically at an angle of 5° to 15° to each other or centrally symmetrically at an angle of 5° to 15° to the same direction.

4. The cooling system for preventing overcooling of a steel strip according to claim 3, characterized in that: When the number of the first aerosol nozzles (311) in an aerosol nozzle row is an even number, the plurality of first aerosol nozzles (311) are centrally symmetrically arranged in the same direction at an angle of 5° to 15°; when the number of the first aerosol nozzles (311) in an aerosol nozzle row is an odd number, the plurality of first aerosol nozzles (311) are centrally symmetrically arranged in opposite directions at an angle of 5° to 15°.

5. The cooling system for preventing overcooling of a steel strip according to claim 4, characterized in that: When the plurality of first aerosol nozzles (311) are arranged centrally and symmetrically at an angle of 5° to 15° towards each other, the spray direction of the air jet (511) is perpendicular to the upper surface of the steel strip (6); when the plurality of first aerosol nozzles (311) are arranged centrally and symmetrically at an angle of 5° to 15° towards each other, the air jet (511) is biased toward the aerosol cooling device (3), and the angle between the spray direction of the air jet (511) and the upper surface of the steel strip (6) is 60° to 70°.

6. The cooling system for preventing overcooling of a steel strip according to claim 2, characterized in that: The first spray frame (31) and the jet nozzle support (51) can both be raised and lowered, the distance between the first aerosol nozzle (311) and the jet nozzle (511) and the roller (1) can be adjusted, the jet nozzle support (51) comprises a rotating support (512), the jet nozzle (511) is connected to the rotating support (512), and the rotating support (512) can adjust the angle between the spray direction of the jet nozzle (511) and the upper surface of the steel strip (6).

7. The cooling system for preventing overcooling of a steel strip according to claim 2, characterized in that: The aerosol cooling device (3) further comprises a second spray rack (34), a second cooling water supply pipeline and a third compressed air supply pipeline. A plurality of second aerosol nozzles (341) are arranged on the second spray rack (34). The second cooling water supply pipeline and the third compressed air supply pipeline are both connected to the second aerosol nozzles (341). The second spray rack (34) and the first spray rack (31) are both capable of moving along a transmission direction perpendicular to the roller conveyor (1). When the first spray rack (31) is located directly above the roller conveyor (1), the second spray rack (34) leaves directly above the roller conveyor (1); when the second spray rack (34) is located directly above the roller conveyor (1), the first spray rack (31) leaves directly above the roller conveyor (1).

8. A cooling method for preventing a steel strip from being overcooled, characterized in that: The cooling method for preventing the steel strip from being overcooled adopts the cooling system for preventing the steel strip from being overcooled according to claim 2, and the cooling method for preventing the steel strip from being overcooled comprises the following steps in sequence: Step 1, establishing an air-water pressure range model and a water film automatic jet model; The spray water pressure and spray air pressure of the aerosol cooling device (3) are adjusted multiple times. The spray water pressure of the aerosol cooling device (3) is in the range of P W To P Wmax The spray pressure of the aerosol cooling device (3) is in the range of P A -P Amax , observing and recording the morphology of the aerosol sprayed by the aerosol cooling device (3) under different spray water pressures and different spray air pressures, and forming an air-water pressure range model; P W is the minimum spray water pressure of the minimum aerosol cooling device (3), P Wmax is the maximum spray water pressure of the minimum aerosol cooling device (3), P A is the minimum injection pressure of the minimum aerosol cooling device (3), P Amax is the maximum injection air pressure of the minimum aerosol cooling device (3); According to the form of the aerosol sprayed by the aerosol cooling device (3) at different spray water pressures and different spray air pressures, and the thickness of the water film remaining on the steel strip (6), the spray air pressure of the spray device (5) is adjusted so that the gas sprayed by the spray device (5) completely blows away the water film on the steel strip (6). The air pressure when the gas sprayed by the spray device (5) completely blows away the water film on the steel strip (6) is the blowing air pressure P j Observe and record the water film thickness and the blowing air pressure P j The corresponding relationship forms a water film automatic jet model, and the range of the water film thickness is L min -L max ; L min is the minimum value of the residual water film thickness on the steel strip (6), L max is the maximum value of the thickness of the water film remaining on the steel strip (6); In step 2, the control unit controls the aerosol cooling device (3) to spray aerosol toward the steel strip (6) according to the vertical air-water pressure range model, and the control unit controls the aerosol cooling device (5) to spray gas toward the steel strip (6) and blow away the water film on the steel strip (6) according to the water film automatic jet model.

9. The cooling method for preventing overcooling of a steel strip according to claim 8, characterized in that: In step 2, When the high temperature metal detector (2) detects the head of the steel strip (6), the control unit first controls the first compressed air switch valve (331) to open, the control unit secondly controls the cooling water switch valve (321) to open, and the control unit again controls the second compressed air switch valve (521) to open; When the high-temperature metal detector (2) detects the tail of the steel strip (6), the control unit first controls the cooling water switch valve (321) to close, the control unit secondly controls the first compressed air switch valve (331) to close, and the control unit again controls the second compressed air switch valve (521) to close.

10. The cooling method for preventing overcooling of a steel strip according to claim 8, characterized in that: In step 2, When the temperature detector downstream of the cooling system for preventing the steel strip from being overcooled detects that the temperature of the steel strip (6) does not meet the standard, the control unit controls the first spray rack (31) to lower its height; After the gas jet device (5) jets gas toward the steel strip (6), the thickness of the water film on the steel strip (6) is still higher than L min When the height of the jet nozzle bracket (51) is lowered, the control unit controls the jet nozzle bracket (51) to lower its height; When the water film thickness detector (4) detects that the water film thickness on the steel strip (6) is less than L min When the air injection device (5) is not started.

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