Program optimization method for sine curve roll shape of working roll for CAPCO grinding machine

Abstract

The invention belongs to the technical field of metallurgy, and provides a method for optimizing a sine curve roll shape of a working roll through a program for a CAPCO grinding machine, which comprises the following steps of: firstly, constructing an ideal curve roll shape of a taper part of the working roll, then designing an empirical curve according to the ideal curve, grinding through the empirical curve, comparing an actually measured value with the ideal curve, and finally obtaining the sine curve roll shape of the working roll. The empirical curve is modified for multiple times according to the comparison result of the measured value and the ideal curve, the measured value of the final empirical curve is overlapped with the ideal curve, and the obtained empirical curve data is stored as final program application data. According to the method, in a certain area of the edge of the roller, the roller type curve conforms to the change rule of the sine curve, and the sine curve is reasonably determined to enable deformation of edge metal to be more uniform and stress distribution to be more reasonable in the rolling process of the roller, so that edge cracks are completely eradicated, the product quality is improved, and the production efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of metallurgy, and relates to a method for optimizing the sinusoidal roll profile of a working roll of a grinding machine program, and specifically provides a method for optimizing the sinusoidal roll profile of a working roll of a CAPCO grinding machine program. Background Art

[0002] The 1450UCWM pickling mill is equipped with K-WRS edge drop control technology. K-WRS edge drop control technology means that when the roll moves axially, the amount of roll shifting gradually increases, and the initial roll gap opening at each point on the edge of the strip increases accordingly, achieving the purpose of offsetting the thinning of the strip edge. This technology measures the edge thickness and performs measurement and analysis through the edge drop meter at the exit, achieving precise control of the axial shifting of the working rolls of the first few stands, thereby achieving automatic control of the edge drop index of the unit. The working roll of the pickling mill is designed to have a total roll length of 1605mm, of which 1450mm is a flat roll. The edge has a sinusoidal roll shape with a taper length of 155mm and a taper bottom that is 0.775 (diameter) lower than the flat roll. Such a roll shape can ensure that the edge of the steel strip is stably and slowly thinned during the roll shifting process during rolling. However, the CAPCOS grinder does not have an available program for single-sided grinding of sinusoidal curves, and can only use the taper setting program to grind the working roll. After grinding, the dimensional curve of the tapered part of the roll does not coincide well with the ideal curve roll shape of the tapered part in the drawing. The edge drop control is not good during rolling of the rolling mill, which can easily cause cracks and broken strips during edge thinning, bringing difficulties to the normal rolling of the continuous rolling mill. Summary of the invention

[0003] The purpose of the present invention is to provide a method for optimizing the sinusoidal roll profile of a working roll of a CAPCO grinder by using a program, so that the measured roll profile curve after grinding of the working roll can coincide with the ideal curve.

[0004] The technical solution adopted by the present invention to achieve the above-mentioned purpose is: A method for optimizing the sinusoidal roll profile of a working roll using a program of a CAPCO grinder comprises the following steps: S1. Construct the ideal curve roll shape of the taper part of the working roll; According to the sine curve formula of the working roll edge of the continuous rolling mill, taking a unit size segment as the benchmark, the height difference of each position is obtained by the formula and drawn into an ideal curve; S2. Design the experience curve based on the ideal curve; In the grinder experience curve program, a unit size segment of the ideal curve is used as a reference to calculate the roller diameter difference in the diameter direction corresponding to each position to obtain an experience curve; S3, through empirical curve grinding, compare the measured value with the ideal curve; Use the experience curve in S2 for grinding. After grinding, manually measure and compare the measured value of each position with the ideal curve to see if they coincide. If they do, the experience curve program is established. If they do not coincide, enter S4. S4, modifying the experience curve multiple times by comparing the measured values ​​with the ideal curve; Input numerical values ​​based on actual measurement results to get a curve that is compared with the ideal curve, and continuously modify the parameters: When the actual measurement result is less than the theoretical curve value, the experience curve value is equal to the previous experience curve value / error coefficient; When the actual measurement result is greater than the theoretical curve value, the experience curve value is equal to the previous experience curve value * error coefficient; The error coefficient is the actual measured value / theoretical curve value; S5, the actual grinding value of the final empirical curve coincides with the ideal curve; Repeat the above steps many times to continuously obtain new empirical curve data and bring it into the program for grinding until the actual measured data curve after grinding coincides with the theoretical curve S6. Save the acquired experience curve data as final program application data.

[0005] The beneficial effects of the present invention are: 1. In a certain area of ​​the roll edge, the roll profile conforms to the changing law of the sine curve. By reasonably determining the wavelength, amplitude and starting phase of the sine curve, the deformation of the edge metal of the roll is more uniform and the stress distribution is more reasonable during the rolling process, thus preventing the occurrence of edge cracks.

[0006] 2. Quality inspection of the rolled products revealed that the edge quality of the products rolled using sinusoidal rollers was significantly better than that of the products rolled using traditional rollers. The edge quality and thickness accuracy of the products were effectively improved.

[0007] 3. The grinding efficiency of the working roll is effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a schematic diagram of the upper and lower working rolls of the 1450UCWM pickling mill; Figure 2 is an ideal curve graph; Figure 3 This is the data comparison table after the first trial grinding; Figure 4 This is the data comparison table after the second trial grinding; Figure 5 is the final grinding data table; Figure 6 is the final grinding curve diagram; Figure 7It is a flow chart for optimizing the sinusoidal roll profile of the working roll. DETAILED DESCRIPTION

[0009] The present invention will be further described below in conjunction with embodiments: Example

[0010] 1450UCWM pickling mill upper and lower working rolls Figure 1 As shown, the working roll of the pickling mill is designed to have a total roll body length of 1605mm, of which 1450mm is a flat roll, and the edge has a sinusoidal roll shape with a taper length of 155mm and a taper bottom that is 0.775 (diameter) lower than the flat roll. The roll shape design of the CAPCO grinder has an "empirical curve program" design function. In this function, the size corresponding to each point of the taper is calculated by the curve formula provided on the drawing. By inputting the size at every 25mm, an "empirical curve" can be obtained. When grinding the roll with this curve, the grinding wheel is not in full contact when grinding the taper, which leads to deviations in the ground roll shape. The method of the present invention is used to correct the empirical curve so that the final grinding measured size curve coincides with the theoretical curve. The steps for setting the empirical curve to optimize the sinusoidal roll shape of the working roll are as follows: Figure 7 As shown, the following steps are included: S1. Construct the ideal curve roll shape of the taper part of the working roll; According to the sine curve formula of the working roll edge of the continuous rolling mill: y=2*155*1 / 400*(sin((360°*x) / (4*155))-1) where: x is the distance from the roll edge 0-155 (mm), y is the roll diameter difference in the diameter direction; Taking 25mm as a size segment, the height difference of each position is obtained by the above formula and plotted into an ideal curve, which is the curve shape that needs to be achieved in actual measurement after the final grinding, such as Figure 2 shown.

[0011] S2. Design the experience curve based on the ideal curve; According to the size segment of 25㎜, calculate the Y value corresponding to each position and input it to obtain an empirical curve.

[0012] S3, through empirical curve grinding, compare the measured value with the ideal curve; Use the empirical curve in S2 for grinding. After grinding, select the tapered part of the working roll, 25mm to 200mm away from the edge, and take one point every 25mm for actual measurement. Check whether the measured value coincides with the ideal curve. If so, the empirical curve program is established; if not, enter S4. The first trial grinding edited the empirical curve data and coincided with the ideal curve. After grinding, the actual measurement was carried out and the result was Figure 3As shown in the table, it was found through the first test grinding that the error of the taper curve produced by roller grinding using the theoretical roller profile curve as the empirical curve was large, the overall taper was ground deeper, and some positions even exceeded 50%.

[0013] S4, modifying the experience curve multiple times by comparing the measured values ​​with the ideal curve; Input numerical values ​​based on actual measurement results to get a curve that is compared with the ideal curve, and continuously modify the parameters: When the actual measurement result is less than the theoretical curve value (grinding depth), the empirical curve value is equal to the previous empirical curve value / error coefficient c; When the actual measurement result is greater than the theoretical curve value (shallow grinding), the experience curve value is equal to the previous experience curve value * error coefficient c, and the error coefficient c is the actual measurement value / theoretical curve value; After calculating the error coefficient, we get the second experience curve data (experience curve 2) as follows: Figure 4 The table data is shown.

[0014] S5, the actual grinding value of the final empirical curve coincides with the ideal curve; Repeat the above steps many times to continuously obtain new empirical curve data and bring it into the program for grinding until the actual measured data curve after grinding coincides with the theoretical curve, such as Figure 5 The table data is shown.

[0015] S6. Save the acquired experience curve data as final program application data.

[0016] The final experience curve data is saved to the program file to generate a roller profile curve, such as Figure 6 shown.

[0017] Through practical application, the edge drop level is under control, and the number of edge cracks and belt breaks caused by the roll shape of the rolling mill has been eliminated. It can be determined that the working rolls ground according to the empirical curve program can meet the design requirements and can be used as the final curve grinding program setting to grind the working rolls.

[0018] Judging from the final effect presented by the embodiment, the method of the present invention solves the problem of mismatch between the actual roll shape of the on-site rolling roll and the theoretical roll shape, and solves the problem of edge drop difference of the steel strip during rolling, thereby effectively reducing the probability of edge cracks caused by the roll shape of the working roll (from about 3% to 0), eliminating the risk of strip breakage due to edge cracks, and improving the operating stability and quality of the unit; before the improvement, the time required to grind a working roll was about 65 minutes, and after the program was improved, the grinding time was reduced to 50 minutes. After using the roller shape experience curve, the grinding time was greatly reduced and the grinding efficiency was improved.

[0019] The stable rolling process and reduced defects can improve production efficiency. There is no need to frequently stop the machine to deal with edge problems or replace rolls. The annual loss due to edge cracks and broken strips is reduced by approximately: (monthly number of rolls 900*12 months*edge crack and broken strip rate 3%*20,000 yuan loss per strip break) 900*12*0.03*2=6.48 million yuan.

Claims

1. A method for optimizing the sinusoidal roll profile of a work roll using a program of a CAPCO grinder, characterized in that: The steps include: S1. Construct the ideal curve roll shape of the taper part of the working roll; According to the sine curve formula of the working roll edge of the continuous rolling mill, taking a unit size segment as the benchmark, the height difference of each position is obtained by the formula and drawn into an ideal curve; S2. Design the experience curve based on the ideal curve; In the grinder experience curve program, a unit size segment of the ideal curve is used as a reference to calculate the roller diameter difference in the diameter direction corresponding to each position to obtain an experience curve; S3, through empirical curve grinding, compare the measured value with the ideal curve; Use the experience curve in S2 for grinding. After grinding, manually measure and compare the measured value of each position with the ideal curve to see if they coincide. If they do, the experience curve program is established. If they do not coincide, enter S4. S4, modifying the experience curve multiple times by comparing the measured values ​​with the ideal curve; Input numerical values ​​based on actual measurement results to get a curve that is compared with the ideal curve, and continuously modify the parameters: When the actual measurement result is less than the theoretical curve value, the experience curve value is equal to the previous experience curve value / error coefficient; When the actual measurement result is greater than the theoretical curve value, the experience curve value is equal to the previous experience curve value * error coefficient; The error coefficient is the actual measured value / theoretical curve value; S5, the actual grinding value of the final empirical curve coincides with the ideal curve; Repeat S4 many times to continuously obtain new empirical curve data and bring it into the program for grinding, until the actual measured data curve after grinding coincides with the theoretical curve; S6. Save the acquired experience curve data as final program application data.

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