Method for improving surface color difference of hot-rolled aluminum plate strip

Abstract

The application provides a method for improving surface color difference of hot-rolled aluminum plate strip, comprising the following steps: carrying out a butter experiment on the surface of a roller to verify the blocking condition of an emulsion nozzle; separately cleaning the emulsion nozzle that appears to be blocked; and controlling the emulsion injection amount during the rolling of the hot-rolled aluminum plate strip. In the method for improving surface color difference of hot-rolled aluminum plate strip provided in the application, the butter experiment is used to verify the uniformity of the emulsion nozzle injection, and the emulsion injection amount is controlled, so that the surface color difference can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aluminum plate processing, and particularly relates to a method for improving surface color difference of hot-rolled aluminum plate strip. BACKGROUND

[0002] Surface color difference of rolled aluminum plate strip has been a key problem bothering aluminum processing enterprises. In the process of hot finishing rolling, since the hot finishing mill sprays emulsion to the roller and aluminum material for cooling, and part of the components of the emulsion volatilize quickly under high-temperature rolling, the surface of the aluminum strip should present a uniform and consistent color after rolling. However, the emulsion nozzle will be blocked in the long-term use process. Due to the blocking of the nozzle, the oil film is less in the place where the emulsion injection amount is less in the width direction of the plate strip, and the frictional resistance is large, so that a color difference band with different depths is formed on the surface corresponding to the nozzle, and further, the surface of the aluminum strip produces color difference phenomenon. The surface color difference phenomenon of the aluminum strip greatly affects the appearance of the product, and in severe cases, the product cannot be delivered. Therefore, it is urgent to solve the problem of surface color difference of hot finishing coiled material.

[0003] Under ideal conditions, the surface of the hot finishing coiled material should be smooth and clean, and the color should be uniform and consistent, and there should be no obvious color difference on the surface. However, due to the serious aging of the hot finishing mill equipment in the calender plant, the emulsion injection improvement means is less, and only manual visual inspection of the nozzle blocking condition can be relied on, so the emulsion nozzle injection quality is extremely unstable, and therefore the problem of surface color difference of the hot finishing coiled material often occurs, which affects the quality of the product. SUMMARY

[0004] The technical problem solved by the present application is to provide a method for improving surface color difference of hot-rolled aluminum plate strip.

[0005] Therefore, the present application provides a method for improving surface color difference of hot-rolled aluminum plate strip, which comprises the following steps:

[0006] Butter experiment is performed on the surface of the roller to verify the blocking condition of the emulsion nozzle;

[0007] The emulsion nozzle which is blocked is cleaned separately;

[0008] The emulsion injection amount is controlled in the process of hot-rolling aluminum plate strip.

[0009] Preferably, the butter experiment specifically comprises:

[0010] Butter is smeared on the surface of the roller, the emulsion is turned on, and the blocking condition and angle of the emulsion nozzle are checked.

[0011] Preferably, the time for turning on the emulsion is 5-20s.

[0012] Preferably, the time for turning on the emulsion is 9-15s.

[0013] Preferably, the temperature of the emulsion is 50-80℃.

[0014] Preferably, the temperature of the emulsion is 55-70℃.

[0015] Preferably, the flow rate of the emulsion is 500-800L / min.

[0016] Preferably, the injection amount of the emulsion is 680-780L / min.

[0017] Preferably, the concentration of the emulsion is 5.0-7.0wt%.

[0018] The present application provides a method for improving the color difference of the surface of hot-rolled aluminum plate strip, which first carries out a butter experiment on the surface of the roller to verify the blocking of the emulsion nozzle, cleans the emulsion nozzle that appears to be blocked, and controls the injection amount of the emulsion during the rolling process of the hot-rolled aluminum plate strip to reduce the contact amount of the emulsion with the surface of the plate strip, so as to realize the improvement of the color difference of the surface of the hot-rolled aluminum plate strip. In the method for improving the color difference of the surface of the hot-rolled aluminum plate strip provided by the present application, the butter experiment is used to verify the uniformity of the emulsion nozzle and the blocking of the nozzle, and the blocked nozzle is cleaned, and the injection amount of the emulsion is controlled to reduce the color difference of the surface of the plate strip. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The photo of the nozzle condition at the inlet side before the roller is installed in the present application;

[0020] Figure 2 The photo of the nozzle condition at the outlet side before the roller is installed in the present application;

[0021] Figure 3 The photo of the roller condition at the inlet side after the emulsion is injected in the present application;

[0022] Figure 4 The photo of the roller condition at the outlet side after the emulsion is injected in the present application;

[0023] Figure 5 The photo of the surface of the plate before the nozzle is cleaned in the present application;

[0024] Figure 6 The photo of the surface of the plate after the nozzle is cleaned in the present application. DETAILED DESCRIPTION

[0025] In order to further understand the present application, the preferred embodiments of the present application are described below in combination with examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present application, and are not limitations of the claims of the present application.

[0026] In view of the color difference problem of the hot finish rolled coil surface in the prior art, the application provides a method for improving the color difference of the hot rolled aluminum plate strip surface. The method can reduce the occurrence of color difference by periodically detecting the blockage of the nozzle and separately cleaning, and can also reduce the occurrence of surface color difference by controlling the emulsion injection amount during rolling. Specifically, the application discloses a method for improving the color difference of the hot rolled aluminum plate strip surface, comprising the following steps:

[0027] Performing a butter test on the roll surface to verify the blockage of the emulsion nozzle;

[0028] Separately cleaning the emulsion nozzle that is blocked;

[0029] Controlling the emulsion injection amount during the rolling of the hot rolled aluminum plate strip.

[0030] In the application, the butter test specifically includes:

[0031] Applying butter on the roll surface, turning on the emulsion, and checking the blockage and angle of the emulsion nozzle.

[0032] During the above butter test, the emulsion is turned on for 5-20s, the temperature of the emulsion is 50-80℃, and the flow rate of the emulsion is 500-800L / min. More specifically, the emulsion is turned on for 9-15s, the temperature is 55-70℃, and the flow rate of the emulsion is 700-780L / min. After turning on the emulsion, whether the nozzle sprays uniformly on the roll surface is observed, and whether the nozzle is blocked is detected. By applying butter on the roll surface and simulating the use of emulsion in production, after the emulsion injection is completed, the appearance of the butter after being washed is observed to determine the blockage of the nozzle. If a color band appears in the middle of the roll, it indicates that the nozzle in the middle is blocked.

[0033] After the above butter test, if the emulsion nozzle is blocked, it is separately cleaned. At the same time, during the rolling of the hot rolled aluminum plate strip, the emulsion injection amount is controlled to be 680-750L / min, more specifically 700-720L / min, the concentration of the emulsion is 5.0-7.0%, and specifically the concentration of the emulsion is 5.5-6.5%. In actual production, the emulsion is prone to surface residue in a low temperature environment. In order to reduce the residue of the emulsion on the aluminum plate strip, the emulsion injection amount can be reduced, for example, from the original 100% to 50%.

[0034] In order to further understand the application, the method for improving the color difference of the hot rolled plate strip surface provided by the application is described in detail below in combination with the embodiments, and the protection scope of the application is not limited by the following embodiments.

[0035] Embodiment

[0036] 1) Butter test

[0037] After the rollers are evenly coated with butter (without brush roller and guard plate), the emulsion is turned on for 5 seconds (2 seconds for each of the turning on and turning off, totally 9 seconds), the emulsion spraying condition and angle are checked, the emulsion temperature is 55℃, and the stable emulsion flow is 750±30 L / min.

[0038] The test results show that the emulsion angle direction is basically not problematic, the horizontal comparison is uniform, and the gap is about 200 mm; the inlet side: the upper roller middle part and the transmission side are partially blocked, and the lower roller middle part is blocked more; the outlet side: the upper roller middle part and the transmission side edge are partially blocked, and the lower roller two sides are obviously blocked; the specific conditions are as follows:

[0039] 2) The schematic diagram of the inlet side nozzle before the rollers are installed is shown in Figure 1 , the schematic diagram of the outlet side nozzle before the rollers are installed is shown in Figure 2 , and the schematic diagram of the roller after spraying at the inlet side is shown in Figure 3 , as shown in Figure 3 , the nozzle at the square frame is more blocked, the schematic diagram of the roller after spraying at the outlet side is shown in Figure 4 , as shown in Figure 4 , the nozzle at the square frame is more blocked.

[0040] 3) The center and both sides of the emulsion nozzle are cleaned, the surface photo of the coil before the nozzle is cleaned is shown in Figure 5 , the aluminum plate is hot-rolled after the nozzle is cleaned, the related parameters of the emulsion (concentration 6.5%, pH value 7.6, conductivity 720 us / cm, stable emulsion flow 750±30 L / min, and emulsion spraying amount 700 L / min); the surface photo of the coil is shown in Figure 6 .

[0041] The above description of the embodiments is only used to help understand the method of the present application and its core idea. It should be noted that, for those skilled in the art, some improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

[0042] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for improving the surface color difference of a hot-rolled aluminum sheet strip, comprising the following steps: A butter test was conducted on the roller surface to verify the blockage of the emulsion nozzle; Clean the clogged emulsion nozzles separately; During the rolling process of the hot-rolled aluminum sheet and strip, the emulsion injection amount is controlled to be 700-720 L / min, and the emulsion concentration is 5.5-6.5 wt%; The butter experiment is specifically as follows: Apply butter to the roller surface, turn on the emulsion, and check the emulsion nozzle blockage and emulsion angle; During the above butter experiment, the time to open the emulsion was 9-15 seconds, the temperature of the emulsion was 55-70°C, and the flow rate of the emulsion was 700-780 L / min; After turning on the emulsion, observe whether the emulsion nozzle sprays evenly on the roller surface. Apply butter on the roller surface and simulate the use of emulsion during production. After the emulsion spraying is completed, observe the morphology of the butter after flushing to determine the blockage of the emulsion nozzle.

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