Production device and method for improving surface quality of strip steel of acid continuous rolling product

Abstract

The invention discloses a production device and method for improving the surface quality of strip steel of an acid continuous rolling product, and belongs to the technical field of acid continuous rolling production processes. The technical problem that defects such as spots, dark marks and stripes often appear on the surface is solved. The device comprises a pickling unit, a wringing roller, a rinsing unit, a re-brushing machine, a spraying device, a face blowing device, an edge blowing device and a drying machine. The pickling unit is provided with three sections of continuous hydrochloric acid pickling tanks, the rinsing unit is closely connected with the pickling unit, the re-brushing machine is arranged at an outlet of the rinsing unit, and the re-brushing machine, the spraying device, the face blowing device, the edge blowing device and the drying machine are sequentially connected. The method has the advantages that the generation of color difference defects is effectively reduced, the watermark defects on the surface of the strip steel are removed, and raw materials with excellent surface quality are provided for a subsequent unit, so that the purpose of greatly improving the quality of a final cold-rolled product is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of pickling continuous rolling production process, and particularly relates to a production device for improving the surface quality of pickling continuous rolling product strip steel, which is suitable for the pickling process section production of strip steel pickling, rinsing, grinding, blowing and drying processes to reduce surface defects of strip steel. Background Art

[0002] At present, the market has increasingly higher requirements for the surface quality of cold-rolled high-end automotive outer panels, especially GA series automotive outer panels, which have extremely stringent requirements for the surface quality of products. The pickling mill is the first process in the overall cold rolling process, and the surface quality of its products directly affects the quality of the subsequent units, especially the control and operation of the pickling process section, which is directly related to the quality of high-end automotive outer panels. However, in conventional pickling continuous rolling mills, after the strip is pickled, rinsed, and dried, color differences, dark prints, and stripe defects often appear on the surface. In order to improve the surface quality of cold-rolled high-end automotive plates and the subsequent customer yield and production efficiency, these defects that affect the surface quality are urgent problems that need to be solved. Summary of the invention

[0003] The purpose of the present invention is to provide a production device for improving the surface quality of pickled continuous rolling product strip, improve and perfect the pickling, rinsing and drying processes in the conventional pickling process of pickling continuous rolling, add re-brushing, spraying, blowing and other processes, and solve the technical problems of spots, dark marks and stripes that often appear on the surface.

[0004] A production device for improving the surface quality of pickled continuous rolling product strip steel comprises a pickling unit 1, a squeeze roller 2, a rinsing unit 3, a heavy brushing machine 4, a spraying device 5, a face blowing device 6, an edge blowing device 7, and a drying machine 8;

[0005] The pickling unit 1 is provided with three-stage continuous hydrochloric acid pickling tanks, the rinsing unit 3 is closely connected with the pickling unit 1, and a re-brushing machine 4 is arranged at the outlet of the rinsing unit 3, and the re-brushing machine 4, the spraying device 5, the face blowing device 6, the edge blowing device 7 and the drying machine 8 are connected in sequence;

[0006] A squeeze roller 2 is installed between the hydrochloric acid pickling tank, at both ends of the inlet and outlet of the heavy brushing machine 4, and at both ends of the inlet and outlet of the face cleaning device 6.

[0007] The rebrushing machine 4 comprises an inlet squeeze roller 2, a brush roller 9, and an external spray device 10. The outlet squeeze roller 2 and the external spray device 10 are above and below the surface of the strip and form a certain angle with the brush roller 10.

[0008] A production method for improving the surface quality of acid continuous rolling product strip steel, the specific steps are as follows:

[0009] Step 1: After the strip is processed by the pickling unit and the rinsing unit, the loose iron oxide scale is removed, and a small amount of dense iron oxide scale is closely combined with the matrix. If this type of iron oxide scale remains, it will form color difference defects on the surface of the pickled plate;

[0010] Step 2: Use a heavy brushing machine to mechanically grind the surface of the strip with a roller brush to remove foreign matter on the surface of the strip and improve the surface quality of the pickled plate;

[0011] Step 3: For GA series products that need to be hot-dip galvanized later, re-brushing is performed to increase the surface roughness, so as to enhance the adhesion of the coating and make the galvanized layer more firmly bonded to the steel base surface;

[0012] Step 4: After being processed by the re-brushing machine, the upper and lower surfaces of the strip are immediately rinsed with water through the spray device, and under the action of the subsequent squeezing roller, a layer of flushing water is evenly distributed on the surface of the strip to prevent the strip from directly contacting the air to form watermarks;

[0013] Step 5: The surface blowing device is used to blow the entire surface of the strip to blow away the flushing water on the surface of the strip; the subsequent squeezing roller squeezes out the moisture in the middle of the strip surface and squeezes the moisture to the edge of the strip, and the edge blowing device blows away the residual moisture on the edge;

[0014] Step 6: The dryer dries the strip as a whole, and finally obtains a strip with almost no spots, color difference, and watermarks on the surface.

[0015] The brushing working steps of the re-brushing machine are as follows: each pair of brush rollers is driven by two variable speed motors to rotate in opposite directions, and the physical friction of the bristles and the mechanical brushing effect are used to achieve the grinding and brushing process; the two pairs of brush rollers respectively use reverse brushing and forward brushing methods, which can not only improve the brushing effect, but also eliminate the tension of the strip;

[0016] The brush rollers rotate at high speed during brushing and continuously contact the strip steel, which will generate a lot of heat. Therefore, two sets of external spray devices are arranged between the two pairs of brush rollers for spray cooling and cleaning the surface of the strip steel to improve the grinding and brushing effect of the strip steel. The spray angle of the nozzle is located between the strip steel and the brush roller to ensure that the strip steel is wetted and the liquid is not thrown to the brushing tank by the brush roller and splashed everywhere; the spraying water volume must be appropriate according to the load requirements.

[0017] The external spray water volume is based on a flow rate of 5 L / min on a roller surface width of 100 mm.

[0018] The advantages of the present invention are that after conventional pickling and rinsing, the stains on the surface of the steel strip that cannot be washed off by chemical pickling and the residual stubborn iron oxide scale are removed by heavy brushing and spraying processes, and the watermark defects on the surface of the steel strip are removed by double blowing and drying processes to ensure the surface quality of the pickled plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the process arrangement of the present invention.

[0020] Figure 2 for Figure 1 Schematic diagram of the structure of a medium and heavy flash machine.

[0021] In the figure, there are a pickling unit 1, a squeeze roller 2, a rinsing unit 3, a heavy brushing machine 4, a spraying device 5, a face blowing device 6, an edge blowing device 7, a drying machine 8; a brush roller 9, and an external spraying device 10. DETAILED DESCRIPTION

[0022] The technical solution in the embodiment of the present invention will be further described below in conjunction with the accompanying drawings in the embodiment of the present invention.

[0023] like Figure 1 The production device for improving the surface quality of the pickled continuous rolling product strip shown in the figure comprises a pickling unit 1, a squeeze roller 2, a rinsing unit 3, a re-brushing machine 4, a spraying device 5, a face sweeping device 6, an edge sweeping device 7, and a drying machine 8. The pickling unit 1 is provided with three-stage continuous hydrochloric acid pickling tanks, and squeeze rollers 2 are arranged between the pickling tanks. The rinsing unit 3 is closely connected with the pickling unit 1. A re-brushing machine 4 is arranged at the outlet of the rinsing unit 3 to grind the surface of the strip after pickling to remove the residual fine iron oxide scale on the surface. The squeeze roller 2 is arranged at the inlet and outlet of the re-brushing machine 4. A spraying device 5 is arranged behind the squeeze roller 2 to clean the surface of the strip. After that, the squeeze roller 2 is arranged to take away the residual cleaning water on the surface of the strip. The face sweeping device 6, the squeeze roller 2 and the edge sweeping device 7 are respectively arranged behind the squeeze roller 2 to sweep the surface of the strip twice, effectively reducing the generation of surface watermarks. Finally, the whole is dried through the drying machine 8.

[0024] After being processed by the pickling unit 1 and the rinsing unit 3, the iron oxide scale with a loose structure is removed, and a small amount of iron oxide scale with a dense structure is closely bonded to the substrate. If this type of iron oxide scale remains, it will form a color difference defect on the surface of the pickled plate. Through the brushing of the re-brushing machine 4, the surface of the strip is mechanically polished with roller brush bristles to remove foreign matter on the surface of the strip and improve the surface quality of the pickled plate. In addition, for the GA series products that need to be hot-dip galvanized later, re-brushing increases the surface roughness, promotes the adhesion of the coating, and makes the galvanized layer more firmly bonded to the steel base surface.

[0025] After being processed by the re-brushing machine 4, the upper and lower surfaces of the strip are immediately rinsed with water by the spray 5, and under the action of the subsequent squeezing roller 2, a layer of flushing water is evenly distributed on the surface of the strip to avoid direct contact between the strip and the air to form watermarks.

[0026] The surface blowing device 6 is used to blow the entire surface of the strip to blow away the flushing water on the surface of the strip. The subsequent squeezing roller 2 squeezes the moisture in the middle of the strip surface and squeezes the moisture to the edge of the strip, and the edge blowing device 7 blows away the residual moisture on the edge. The dryer 8 dries the strip as a whole, and finally obtains a strip with almost no spots, color difference, and watermarks on the surface.

[0027] Figure 2 for Figure 1 The structural diagram of the medium and heavy flash machine, combined with Figure 2 The rebrushing machine is provided with an inlet squeeze roller 2, two pairs of brush rollers 9 for brushing the surface of the strip steel, two pairs of external spray devices 10 between the brush rollers, and an outlet squeeze roller 2 in sequence along the production direction.

[0028] Combination Figure 2 Each pair of brush rollers 9 is driven by two variable speed motors to rotate in opposite directions, and the physical friction of the bristles and the mechanical brushing effect are used to achieve the grinding and brushing process. The two pairs of brush rollers adopt reverse brushing and forward brushing respectively, which can not only improve the brushing effect, but also eliminate the tension of the strip.

[0029] Combination Figure 2 The brush roller 9 rotates at high speed during brushing and continuously contacts the strip steel, which will generate a lot of heat. Therefore, two groups of spray beams 10 are arranged between the two pairs of brush rollers for external spray cooling. In addition, spraying can also clean the surface of the strip steel and improve the grinding and brushing effect of the strip steel. The nozzle spray angle is located between the strip steel and the brush roller, which can ensure that the strip steel is wetted without splashing the liquid to the brushing tank body by the brush roller. The external spraying requires a certain appropriate amount of spray water according to the load. The flow rate standard is 5L / min on a roller width of 100mm.

Claims

1. A production device for improving the surface quality of acid continuous rolling product strip, characterized in that: It comprises a pickling unit (1), a squeezing roller (2), a rinsing unit (3), a heavy brushing machine (4), a spraying device (5), a face blowing device (6), an edge blowing device (7), and a drying machine (8); The pickling unit (1) is provided with a three-stage continuous hydrochloric acid pickling tank, the rinsing unit (3) is closely connected with the pickling unit (1), a re-brushing machine (4) is arranged at the outlet of the rinsing unit (3), and the re-brushing machine (4), a spraying device (5), a face blowing device (6), a side blowing device (7) and a drying machine (8) are connected in sequence; A squeeze roller (2) is installed between the hydrochloric acid pickling tank, at both ends of the inlet and outlet of the heavy brushing machine (4), and at both ends of the inlet and outlet of the facial cleaning device (6).

2. The production device according to claim 1, characterized in that: The rebrushing machine (4) comprises an inlet squeeze roller (2), a brush roller (9), and an external spray device (10); the outlet squeeze roller (2) and the external spray device (10) are arranged above and below the surface of the strip steel and form a certain angle with the brush roller (10).

3. A production method for improving the surface quality of acid continuous rolling product strip, characterized in that: The specific method is as follows: Step 1: After the strip is processed by the pickling unit and the rinsing unit, the loose iron oxide scale is removed, and a small amount of dense iron oxide scale is closely combined with the matrix. If this type of iron oxide scale remains, it will form color difference defects on the surface of the pickled plate; Step 2: Use a heavy brushing machine to mechanically grind the surface of the strip with a roller brush to remove foreign matter on the surface of the strip and improve the surface quality of the pickled plate; Step 3: For GA series products that need to be hot-dip galvanized later, re-brushing is performed to increase the surface roughness, so as to enhance the adhesion of the coating and make the galvanized layer more firmly bonded to the steel base surface; Step 4: After being processed by the re-brushing machine, the upper and lower surfaces of the strip are immediately rinsed with water through the spray device, and under the action of the subsequent squeezing roller, a layer of flushing water is evenly distributed on the surface of the strip to prevent the strip from directly contacting the air to form watermarks; Step 5: The surface blowing device is used to blow the entire surface of the strip to blow away the flushing water on the surface of the strip; the subsequent squeezing roller squeezes out the moisture in the middle of the strip surface and squeezes the moisture to the edge of the strip, and the edge blowing device blows away the residual moisture on the edge; Step 6: The dryer dries the strip as a whole, and finally obtains a strip with almost no spots, color difference, and watermarks on the surface.

4. The production method according to claim 3, characterized in that The brushing working steps of the re-brushing machine are as follows: each pair of brush rollers is driven by two variable speed motors to rotate in opposite directions, and the physical friction of the bristles and the mechanical brushing effect are used to achieve the grinding and brushing process; the two pairs of brush rollers respectively use reverse brushing and forward brushing methods, which can not only improve the brushing effect, but also eliminate the tension of the strip; The brush rollers rotate at high speed during brushing and continuously contact the strip steel, which will generate a lot of heat. Therefore, two sets of external spray devices are arranged between the two pairs of brush rollers for spray cooling and cleaning the surface of the strip steel to improve the grinding and brushing effect of the strip steel. The spray angle of the nozzle is located between the strip steel and the brush roller to ensure that the strip steel is wetted and the liquid is not thrown to the brushing tank by the brush roller and splashed everywhere; the spraying water volume must be appropriate according to the load requirements.

5. The production method according to claim 4, characterized in that The external spray water volume is based on a flow rate of 5 L / min on a roller surface width of 100 mm.

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