Device for improving strip-shaped defects on lower surface of aluminum alloy strip and working method

Abstract

The invention relates to a device for improving strip-shaped defects on the lower surface of an aluminum alloy strip and a working method.The device is sequentially provided with an inlet tensioning roller set, a first guide plate, a second guide plate and a working roller set from the feeding side to the discharging side, and the second guide plate is a guide plate fixedly arranged below the aluminum alloy strip; an oil spray nozzle for spraying rolling oil to the lower surface of the aluminum alloy strip is fixedly arranged below the second guide plate; the first guide plate is installed on the liftable sliding block and located below the aluminum alloy strip, and an adjustable lifting roller used for adjusting the tension force of the strip is fixedly arranged on the liftable sliding block and located above the aluminum alloy strip. And meanwhile, the capacity of equipment is widened, the quality of products of various models is guaranteed, and the problem of strip-shaped color difference defects of the lower surface of the high-Mg aluminum alloy strip is thoroughly solved.

Description

Technical field: The invention relates to a device and a working method for improving strip defects on the lower surface of an aluminum alloy strip. Background technology: When the applicant was producing aluminum alloys with a Mg content ≥ 4% (high Mg aluminum alloy), it was found that during the acceptance of the finished products, strip-shaped continuous or intermittent color defects often appeared in the middle area of ​​the width of the aluminum strip, which seriously affected the customer's use and had a great impact on the product yield. Since the product is rolled from 3.5mm to 0.2mm thick, it needs to go through multiple rolling, cleaning, annealing and other processes. The poor product quality caused huge losses to the company.

[0003] After repeated observation, it was found that the continuous or intermittent color difference defects of aluminum alloy strips are mainly concentrated on the lower surface of the aluminum alloy strips. The reason is that during the cold rolling process, the rolling oil sprayed by the rolling mill is easy to gather on the upper surface of the aluminum alloy strips. Since there is a lot of oil on the upper surface of the aluminum alloy strips, on the one hand, it is easy to take away the aluminum powder in time to prevent the aluminum powder from adhering to the rollers, and on the other hand, it can form an oil film between the rollers and the strips to achieve isolation between the strips and the rollers. The lower surface of the aluminum alloy strip is sprayed with rolling oil (there is an oil spraying mechanism at the front end of the tensioning roller inlet). After passing through the tensioning roller, the rolling oil remaining on the lower surface of the aluminum alloy strip is squeezed out. During rolling, the oil film between the strip and the roller is thin. Due to the high strength of the high Mg alloy itself, the oil film is very easy to break and it is not easy to form an isolation layer between the roller and the strip. On the other hand, high Mg alloy is prone to produce aluminum powder during the rolling process. Under the current equipment structure, the aluminum powder is difficult to remove, leaving marks on the lower surface of the aluminum alloy strip, that is, continuous or intermittent strip color difference.

[0004] Although the area of ​​the strip-shaped continuous or discontinuous color difference defects can be reduced to a certain extent by subsequently cleaning the surface of the aluminum alloy strip, adding a cleaning step not only increases the cost and production time, but also fails to fundamentally solve the problem.

[0005] At present, a Chinese patent "A method for solving strip defects on the surface of cold-rolled coils" has been retrieved, with publication number CN119216382A. The method includes: redesigning the composition and hardness of the product, adjusting the hot rolling furnace temperature, increasing the cooling water volume and lowering the coiling temperature during laminar cooling after hot rolling, etc. The method for solving strip defects on the surface of cold-rolled coils provided by the invention improves the hardness of low-carbon steel materials and improves the density of material structure, so that iron oxide scale is not pressed into the surface of hot-rolled coils, reduces the slab heating furnace temperature, and reduces the coiling temperature of hot-rolled coils, thereby solving the pressing of hot-rolled coil oxide scale, so that the hot-rolled coils will not produce strip defects during further cold rolling; but it cannot improve the strip defects on the lower surface of aluminum alloy strips. Summary of the invention: In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a device and a working method for improving strip defects on the lower surface of aluminum alloy strips. The device and the working method for improving strip defects on the lower surface of aluminum alloy strips are reasonably designed and are conducive to improving the strip defects on the lower surface of aluminum alloy strips.

[0007] The device for improving the strip defects on the lower surface of an aluminum alloy strip of the present invention is characterized in that: an inlet tensioning roller group, a first guide plate, a second guide plate and a working roller group are arranged in sequence from the feeding side to the discharging side of the aluminum alloy strip, the second guide plate is a guide plate fixedly arranged below the aluminum alloy strip, and an oil spray nozzle for spraying rolling oil onto the lower surface of the aluminum alloy strip is fixedly arranged below the second guide plate; the first guide plate is installed on a liftable slider and is located below the aluminum alloy strip, an adjustable lift roller for adjusting the tension of the strip is fixedly arranged on the liftable slider and above the aluminum alloy strip, the first guide plate has two working positions, in the first working position, the first guide plate is higher than or flush with the second guide plate and the adjustable lift roller does not press the aluminum alloy strip, in the second working position, the first guide plate is lower than the second guide plate and the first guide plate does not block the oil spray nozzle from spraying rolling oil onto the lower surface of the aluminum alloy strip, and the adjustable lift roller presses the aluminum alloy strip.

[0008] Preferably, a fixing frame is installed below the second guide plate, and the fuel injector is installed on the fixing frame.

[0009] Preferably, an oil spray pipe parallel to the axis of the adjustable lifting roller is installed on the above-mentioned fixed frame, a plurality of oil spray nozzles are arranged on the oil spray pipe, an oil inlet nozzle is fixed on the lower part of the oil spray pipe, and the oil inlet nozzle is connected to the main pipeline of the rolling oil.

[0010] Preferably, a central oil hole connected to the inner cavity of the fuel injection pipe is provided at the center of the fuel injector, and a recessed groove connected to the central oil hole is provided on the free end face of the fuel injector, and the symmetric center plane of the recessed groove forms an angle of 10 degrees with the first plane passing through the axis line of the central oil hole and the axis line of the fuel injection pipe.

[0011] Preferably, the above-mentioned sink groove is a rectangular sink groove or a trapezoidal sink groove, and the width of the bottom of the sink groove is equal to the diameter of the central oil hole.

[0012] Preferably, the first plane forms an angle of 30-60 degrees with the vertical surface.

[0013] Preferably, the liftable slider is slidably connected to a vertical guide rail, the vertical guide rail is fixed to a frame, a hydraulic cylinder is fixedly connected to the frame, and a free end of a telescopic rod of the hydraulic cylinder is connected to the liftable slider.

[0014] Preferably, 7 fuel injectors are evenly arranged at a spacing of 60 mm in the upper middle portion of the fuel injection pipe; and 4 fuel injectors are arranged at a spacing of 120 mm at the outermost sides of the 7 fuel injectors.

[0015] Preferably, the above-mentioned entrance tensioning roller group includes two lower tensioning rollers located below the aluminum alloy strip and an entrance upper tensioning roller located above the aluminum alloy strip, and the entrance upper tensioning roller is located between the two lower tensioning rollers, and the working roller group includes at least an upper working roller and a lower working roller that are rolled relative to each other.

[0016] The present invention uses the working method of the device for improving the strip defects on the lower surface of the aluminum alloy strip. In the non-rolling state, that is, the first guide plate and the adjustable lifting roller are in the first position, at this time, the first guide plate is higher than or flush with the second guide plate and the adjustable lifting roller does not press the aluminum alloy strip. At this time, the aluminum alloy strip passes through the inlet tensioning roller group, the first guide plate, the second guide plate and the working roller group in sequence from the feeding side to realize the introduction of the strip; In the rolling state, that is, the first guide plate and the adjustable lifting roller are in the second position, at this time, the first guide plate is lower than the second guide plate and the first guide plate does not block the oil nozzle from spraying rolling oil to the lower surface of the aluminum alloy strip, and the adjustable lifting roller presses the aluminum alloy strip; the rolling oil sprayed from the nozzle is sprayed onto the lower surface of the aluminum alloy strip, so as to flush the lower surface of the aluminum alloy strip and reduce the amount of aluminum powder remaining on the surface of the aluminum alloy strip; and the sprayed rolling oil adheres to the lower surface of the aluminum alloy strip, which can play a good lubrication and isolation role when the aluminum alloy strip is rolled.

[0017] The working principle of the device for improving the strip defects on the lower surface of the aluminum alloy strip of the present invention is that in the non-rolling state, that is, the first guide plate and the adjustable lifting roller are in the first working position, at this time, the first guide plate is higher than or flush with the second guide plate and the adjustable lifting roller does not press the aluminum alloy strip, so that it is beneficial for the aluminum alloy strip to pass through the entrance tensioning roller group, the first guide plate, and the second guide plate in sequence and then enter the working roller group to realize the introduction of the strip. In this process, the aluminum alloy strip is not blocked and can be supported and guided by the first guide plate and the second guide plate, ensuring that the end of the aluminum alloy strip can be accurately introduced into the working roller group, avoiding the aluminum alloy strip from failing to be accurately introduced into the working roller group Roller group; when in the rolling state, the first guide plate and the adjustable lifting roller are in the second position, at this time the first guide plate is lower than the second guide plate and the first guide plate does not block the oil nozzle from spraying rolling oil to the lower surface of the aluminum alloy strip, so that the rolling oil sprayed by the oil nozzle can be sprayed to the lower surface of the aluminum alloy strip, so as to flush the lower surface of the aluminum alloy strip and reduce the amount of aluminum powder remaining on the surface of the aluminum alloy strip, and the sprayed rolling oil adheres to the lower surface of the aluminum alloy strip, which can play a good lubrication and isolation role when the aluminum alloy strip is rolled; at the same time, the adjustable lifting roller can press the aluminum alloy strip to achieve the adjustment of the wrap angle and tension of the aluminum alloy strip. Description of the drawings: Figure 1 It is a schematic diagram of the construction of the prior art; Figure 2 It is a schematic diagram of the structure of the first station of the present invention; Figure 3 It is a schematic diagram of the structure of the second station of the present invention; Figure 4 yes Figure 3 A partial view of Figure 5 yes Figure 4 The M-direction local view; Figure 6 yes Figure 5 N-direction local cross-sectional view; Figure 7 yes Figure 5 Bottom view of . Specific implementation method: The method of the present invention is further described in detail below in conjunction with the embodiments. It should be particularly noted that the protection scope of the present invention should include but is not limited to the technical content disclosed in this embodiment.

[0020] In the prior art, the aluminum alloy strip 1 is provided with an entrance tensioning roller group 2, a guide plate A and a working roller group 5 in sequence from the feeding side to the discharging side, that is, only a fixed guide plate A is installed between the entrance tensioning roller group 2 and the working roller group 5, and the guide plate A cannot move. Moreover, the spacing between the guide plate A and the entrance tensioning roller group 2 and the working roller group 5 is relatively narrow (only 2-5 mm). The function of the guide plate is only to facilitate the guiding of the strip during feeding, so as to prevent the strip from sagging and being unable to be accurately introduced between the upper working roller 51 and the lower working roller 52. The specific technical scheme of the device for improving the strip defects on the lower surface of the aluminum alloy strip in the present application is as follows.

[0021] The aluminum alloy strip 1 is provided with an inlet tensioning roller group 2, a first guide plate 3, a second guide plate 4 and a working roller group 5 in sequence from the feeding side to the discharging side, as shown in the figure.

[0022] The above-mentioned inlet tensioning roller group 2 includes two lower tensioning rollers 21 located below the aluminum alloy strip and an inlet upper tensioning roller 22 located above the aluminum alloy strip, the inlet upper tensioning roller is located between the two lower tensioning rollers, and the working roller group 5 includes at least an upper working roller 51 and a lower working roller 52 that are rolled relative to each other.

[0023] The second guide plate 4 is a guide plate fixedly arranged below the aluminum alloy strip, one end of the second guide plate 4 is close to the working roll group 5, the other end of the second guide plate 4 is close to one end of the first guide plate 3, the other end of the first guide plate 3 is close to the entrance tensioning roll group 2, and an oil nozzle 6 for spraying rolling oil onto the lower surface of the aluminum alloy strip is fixedly arranged below the second guide plate 4.

[0024] The first guide plate 3 is installed on the liftable slider 7 and is located below the aluminum alloy strip. An adjustable lift roller 8 for adjusting the strip tension is fixed on the liftable slider 7 and above the aluminum alloy strip. That is, the guide plate A is replaced by the first guide plate 3, the second guide plate 4 and the adjustable lift roller 8. The spacing between the adjustable lift roller 8 and the first guide plate 3 is 10-300mm.

[0025] The first guide plate has two working positions. In the first working position, the first guide plate is higher (1-3 mm higher) or flush with the second guide plate and the adjustable lifting roller does not press the aluminum alloy strip. In the second working position, the first guide plate is lower than the second guide plate and the first guide plate does not block the oil nozzle from spraying rolling oil onto the lower surface of the aluminum alloy strip, and the adjustable lifting roller presses the aluminum alloy strip.

[0026] During specific operation, in the non-rolling state, that is, the first guide plate and the adjustable lifting roller are in the first station (upper station), at this time, the first guide plate is higher than or flush with the second guide plate and the adjustable lifting roller does not press the aluminum alloy strip (the first guide plate blocks the oil nozzle from spraying rolling oil to the lower surface of the aluminum alloy strip, and the oil nozzle does not spray oil at this time, thereby not wasting rolling oil), which is conducive to the aluminum alloy strip passing through the entrance tensioning roller group, the first guide plate, and the second guide plate in sequence and then entering the working roller group to realize the introduction of the strip. In this process, the aluminum alloy strip is not blocked and can be supported and guided by the first guide plate and the second guide plate (the same as the existing guide plate), ensuring that the end of the aluminum alloy strip can be accurately introduced between the upper working roller 51 and the lower working roller 52 of the working roller group, avoiding The aluminum alloy strip is not accurately introduced into the working roll group; in the rolling state, the first guide plate and the adjustable lifting roller are in the second station (lower station), at this time, the first guide plate is lower than the second guide plate and the first guide plate does not block the oil nozzle from spraying rolling oil to the lower surface of the aluminum alloy strip (that is, the space for the oil nozzle to spray rolling oil to the lower surface of the aluminum alloy strip is open), so that the rolling oil sprayed by the oil nozzle can be sprayed to the lower surface of the aluminum alloy strip, so as to flush the lower surface of the aluminum alloy strip and reduce the amount of aluminum powder remaining on the surface of the aluminum alloy strip. The sprayed rolling oil adheres to the lower surface of the aluminum alloy strip, which can play a good lubrication and isolation role when the aluminum alloy strip is rolled; at the same time, the adjustable lifting roller can press the aluminum alloy strip to achieve the adjustment of the wrap angle and tension of the aluminum alloy strip.

[0027] The structural design of the first guide plate and the adjustable lifting roller and the two working stations of the present invention realize multiple functions, namely, they meet the function of guiding the strip, and can spray rolling oil on the lower surface of the strip when the installation space of the oil spray nozzle is limited to improve the problem of strip defects on the lower surface, and at the same time can adjust the strip wrap angle and tension.

[0028] A fixing frame 9 is installed below the above-mentioned second guide plate 4, and the fixing frame 9 is fixed on the frame. The oil nozzle 6 is installed on the fixing frame 9. Specifically, an oil injection pipe 61 parallel to the axis of the adjustable lifting roller is installed on the fixing frame, and a plurality of oil injection nozzles 6 are arranged on the oil injection pipe. An oil inlet nozzle 62 is fixed on the lower part of the oil injection pipe 61, and the oil inlet nozzle is connected to the main pipeline of the rolling oil (not shown in the figure). The rolling oil enters the inner cavity of the oil injection pipe 61 through the main pipeline and the oil inlet nozzle 62, and then is sprayed out from each oil nozzle 6.

[0029] For the sake of reasonable design, a central oil hole 63 communicating with the inner cavity of the fuel injection pipe is provided at the center of the fuel injector 6, and a sink groove 64 communicating with the central oil hole 63 is provided on the free end face of the fuel injector (the sink groove 64 is a rectangular sink groove or a trapezoidal sink groove, and the width of the bottom of the sink groove is equal to the diameter of the central oil hole). The symmetric center plane 66 of the sink groove forms an angle of 10 degrees with a first plane 65 passing through the axis of the central oil hole and the axis of the fuel injection pipe. When the angle between the first plane 65 and the symmetric center plane 66 of the sink groove is between 0 and 9 degrees, the injected oil will overlap (that is, the oil sprayed from two adjacent fuel injectors interferes with each other), which is not conducive to the uniform distribution of the oil.

[0030] In order to spray better and avoid the fuel injection nozzle 6 being blocked by the second guide plate 4, the first plane 65 and the vertical surface 67 form an angle of 30-60 degrees, and the fuel injection nozzle 6 does not interfere with the liftable first guide plate in the vertical direction.

[0031] In order to ensure a reasonable design, 7 fuel injectors are evenly arranged at a spacing of 60 mm in the middle of the fuel injection pipe; 4 fuel injectors are arranged at a spacing of 120 mm on the outermost side of the 7 fuel injectors. The advantage of this arrangement is that the length of the fuel injection pipe matches the width of the aluminum strip, and the small distribution interval in the middle of the fuel injectors is conducive to increasing the injection amount in the middle, increasing the flushing of the lower surface and the amount of rolling oil adhering to the lower surface of the strip. The larger intervals on both sides reduce the diversion of the rolling oil, which is conducive to ensuring the injection amount in the middle.

[0032] The liftable slider 7 is slidably connected to a vertical guide rail 71, and the vertical guide rail 71 is fixed on a frame. A hydraulic cylinder 72 or an electric push rod is fixedly connected to the frame. The free end of the telescopic rod of the hydraulic cylinder is connected to the liftable slider 7. The telescopic rod is driven by the hydraulic cylinder 72 to drive the liftable slider 7, the adjustable lift roller 8 and the first guide plate 3 to move up and down.

[0033] The ground at the location where the device of the present invention is installed is provided with an oil collection pool, so that the sprayed oil and impurities contained therein are collected in the oil collection pool (and subsequently recovered, filtered and reused).

[0034] The device of the present invention makes good use of the movable characteristics of the adjustable lifting roller and the first guide plate, and makes full use of the gap generated by the descent of the adjustable lifting roller and the first guide plate to realize the injection of rolling oil; it fundamentally improves the problem of continuous or intermittent color difference defects in strips, does not require a cleaning procedure, is beneficial to control costs and production efficiency, and at the same time broadens the capacity of the equipment, ensures the quality of various types of products, and thoroughly improves the problem of strip color difference defects on the lower surface of high-Mg aluminum alloy strips.

[0035] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A device for improving strip defects on the lower surface of an aluminum alloy strip, characterized in that: An inlet tensioning roller group, a first guide plate, a second guide plate and a working roller group are arranged in sequence from the feeding side to the discharging side of the aluminum alloy strip. The second guide plate is a guide plate fixedly arranged below the aluminum alloy strip, and an oil spray nozzle for spraying rolling oil onto the lower surface of the aluminum alloy strip is fixedly arranged below the second guide plate; the first guide plate is installed on a liftable slider and is located below the aluminum alloy strip, and an adjustable lift roller for adjusting the tension of the strip is fixedly arranged on the liftable slider and above the aluminum alloy strip. The first guide plate has two working positions. In the first working position, the first guide plate is higher than or flush with the second guide plate and the adjustable lift roller does not press the aluminum alloy strip. In the second working position, the first guide plate is lower than the second guide plate and the first guide plate does not block the oil spray nozzle from spraying rolling oil onto the lower surface of the aluminum alloy strip, and the adjustable lift roller presses the aluminum alloy strip.

2. The device for improving strip defects on the lower surface of aluminum alloy strip according to claim 1, characterized in that: A fixing frame is installed below the second guide plate, and the fuel injection nozzle is installed on the fixing frame.

3. The device for improving strip defects on the lower surface of aluminum alloy strip according to claim 2, characterized in that: An oil spray pipe parallel to the axis of the adjustable lifting roller is installed on the fixed frame, a plurality of oil spray nozzles are arranged on the oil spray pipe, an oil inlet nozzle is fixed on the lower part of the oil spray pipe, and the oil inlet nozzle is connected to the main pipeline of the rolling oil.

4. The device for improving strip defects on the lower surface of an aluminum alloy strip according to claim 3, characterized in that: A central oil hole connected to the inner cavity of the fuel injection pipe is provided at the center of the fuel injector, and a recessed groove connected to the central oil hole is provided on the free end surface of the fuel injector. The symmetric center plane of the recessed groove forms an angle of 10 degrees with a first plane passing through the axis of the central oil hole and the axis of the fuel injection pipe.

5. The device for improving strip defects on the lower surface of aluminum alloy strip according to claim 4, characterized in that: The sink trough is a rectangular sink trough or a trapezoidal sink trough, and the width of the bottom of the sink trough is equal to the diameter of the central oil hole.

6. The device for improving strip defects on the lower surface of aluminum alloy strip according to claim 4, characterized in that: The first plane forms an angle of 30-60 degrees with the vertical plane.

7. The device for improving strip defects on the lower surface of aluminum alloy strip according to claim 4, characterized in that: The liftable slide block is slidably connected to a vertical guide rail, the vertical guide rail is fixed to a frame, a hydraulic cylinder is fixedly connected to the frame, and a free end of a telescopic rod of the hydraulic cylinder is connected to the liftable slide block.

8. The device for improving strip defects on the lower surface of an aluminum alloy strip according to claim 4, 5, 6 or 7, characterized in that: Seven fuel injection nozzles are evenly arranged at a spacing of 60 mm in the upper middle portion of the fuel injection pipe; and four fuel injection nozzles are arranged at a spacing of 120 mm at the outermost sides of the seven fuel injection nozzles.

9. The device for improving strip defects on the lower surface of an aluminum alloy strip according to claim 8, characterized in that: The entry tensioning roller group includes two lower tensioning rollers located below the aluminum alloy strip and an entry upper tensioning roller located above the aluminum alloy strip, the entry upper tensioning roller is located between the two lower tensioning rollers, and the working roller group includes at least an upper working roller and a lower working roller that are rolled relative to each other.

10. A working method of the device for improving strip defects on the lower surface of an aluminum alloy strip according to claims 1 to 9, characterized in that: In the non-rolling state, that is, the first guide plate and the adjustable lifting roller are in the first position, at this time, the first guide plate is higher than or flush with the second guide plate and the adjustable lifting roller does not press the aluminum alloy strip. At this time, the aluminum alloy strip passes through the inlet tensioning roller group, the first guide plate, the second guide plate and the working roller group in sequence from the feeding side to realize the introduction of the strip; In the rolling state, that is, the first guide plate and the adjustable lifting roller are in the second position, at which time the first guide plate is lower than the second guide plate and the first guide plate does not block the oil spray nozzle from spraying rolling oil to the lower surface of the aluminum alloy strip, and the adjustable lifting roller presses the aluminum alloy strip; The rolling oil sprayed from the injection nozzle is sprayed onto the lower surface of the aluminum alloy strip, so as to flush the lower surface of the aluminum alloy strip and reduce the amount of aluminum powder remaining on the surface of the aluminum alloy strip. The sprayed rolling oil adheres to the lower surface of the aluminum alloy strip, which can play a good lubrication and isolation role when the aluminum alloy strip is rolled.

Images