Method for preventing AGC steel displacement of finishing mill

Abstract

The invention discloses a method for preventing the displacement of AGC steel of a finishing mill, which comprises an AGC hydraulic cylinder with a locking plate, two sides of the inner side end of the locking plate are respectively provided with a movable clamping angle plate through bolts, and two sides of the upper part of a cylinder body of the AGC hydraulic cylinder are respectively and additionally provided with a displacement prevention block which is consistent with the cylinder body in appearance. The locking plate is fixed to the upper end face of the upper middle portion of the cylinder body through bolts, and it is guaranteed that clamping corners on the two sides of the locking plate cannot be separated from the AGC cylinder body when the AGC cylinder is placed at the low position. The inner side ends of the movable corner clamping plates abut against the ends of the anti-displacement blocks respectively.

Description

Technical Field

[0001] The present invention relates to a method for preventing the AGC steel from running out of position in a finishing mill. Background Art

[0002] The equipment in the F1-F6 finishing area is the core equipment of the 1750mm hot-rolled strip project of Bayi Iron and Steel Co., Ltd. in Xinjiang. The F1-F6 finishing mills are composed of six four-high non-reversible rolling mills (F1-F6) with full hydraulic screwdown, string roll, and positive bending roll shape control. Since a hydraulic AGC device is installed, the thickness accuracy and shape accuracy of the finished steel strip can be improved. When the AGC cylinder on one side of a certain stand deviates from the center line of the housing, a rolling moment will be generated, resulting in a decrease in the unilateral rolling force of the rolling mill, causing a cross-sectional wedge in the strip, and the strip running deviation will affect the shape control of the subsequent stands, reducing the thickness accuracy and shape accuracy of the finished steel strip. When the distance that the AGC cylinder deviates from the center line of the housing exceeds 20 mm, the rolling mill cannot be calibrated, resulting in equipment failures. Through the analysis of product quality problems and equipment failure reasons in the past two years, it is found that: due to the AGC cylinder running out of position and deviating from the center line of the housing, quality problems such as out-of-tolerance thickness of the strip product and edge waviness account for 40%, and the equipment failure time is 185 minutes / year. A total of 120 tons / year of products with quality problems are caused, and the production reduction loss is 1500 tons / year.

[0003] Before the improvement, the AGC cylinder was fixed by an integral locking plate. During normal steel rolling, the AGC cylinder body was clamped by the clamping corners on both sides of the locking plate, and the AGC cylinder would not run out of position and deviate from the center line of the housing. When changing the roll, the AGC cylinder needs to be placed at a low position to adjust the position of the step pad. At this time, the clamping corners on both sides of the locking plate will be disengaged from the AGC cylinder body by the upper end face of the locking plate, and the AGC cylinder is in a free state. When the AGC cylinder is lifted after changing the roll, affected by vibration and uneven lifting force, the AGC cylinder body will shift and rub against one of the clamping corners of the locking plate. When the wear amount of one of the clamping corners of the locking plate is relatively large, the AGC cylinder will deviate from the center line of the housing after being lifted. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for preventing the AGC steel from running out of position in a finishing mill, which can avoid product quality problems and equipment failures caused by the AGC cylinder running out of position.

[0005] The technical solution adopted by the present invention is a method for preventing the AGC steel from running out of position in a finishing mill, including an AGC hydraulic cylinder with a locking plate. On both sides of the inner end of the locking plate, a movable clamping corner plate is respectively installed by bolts. On both sides of the upper part of the cylinder body of the AGC hydraulic cylinder, anti-running-out blocks with the same shape as the cylinder body are respectively installed and fixed on the upper end face of the middle and upper parts of the cylinder body to ensure that the clamping corners on both sides of the locking plate will not disengage from the AGC cylinder body when the AGC cylinder is placed at a low position; the inner ends of the movable clamping corner plates respectively abut against the ends of the anti-running-out blocks.

[0006] In order to prevent the AGC hydraulic cylinder of the finishing mill from running out of position, under the existing resources and equipment conditions, the inventor analyzed the reasons for the running-out of position of the AGC hydraulic cylinder and concluded that: 1. There are defects in the structure of the AGC cylinder body. There are vacant parts at the joint between the upper part of the cylinder body and the locking plate. That is, when the AGC cylinder is placed at the low position, the clamping corners on both sides of the locking plate will disengage from the AGC cylinder body; 2. The locking plate is an integral structure. When excessive wear occurs at the clamping corner parts on both sides, the entire locking plate needs to be replaced. The maintenance time for replacing a set (two) of locking plates is 8 hours. Due to production scheduling and maintenance resource problems, it is often impossible to ensure the timely replacement of the locking plate. After finding the reasons, the method for preventing the AGC hydraulic cylinder of the finishing mill from running out of position was determined: 1. Improve the structure of the AGC cylinder body: Install an anti-running-out block with the same shape as the cylinder body on the upper part of the existing AGC cylinder body, and fix it with bolts on the upper end face of the middle and upper part of the cylinder body to ensure that the clamping corners on both sides of the locking plate will not disengage from the AGC cylinder body when the AGC cylinder is placed at the low position; 2. Improve the structure of the locking plate: Change the locking plate to a split type, that is, design the clamping corner part as a movable part and connect and fix it with bolts to the main body part of the locking plate. When the clamping corner is worn, the clamping corner part can be quickly replaced. The above two measures are used together to constitute a method for preventing the AGC hydraulic cylinder from running out of position, achieving the purpose of preventing the AGC hydraulic cylinder from running out of position.

[0007] After the application of the present invention: 1. After the installation of the anti-running-out block of the AGC cylinder, it avoids the problem that when the AGC cylinder is placed at the low position, the clamping corners on both sides of the locking plate will disengage from the AGC cylinder body, making the AGC cylinder in a free state and easily affected by vibration and lifting torque, resulting in the running-out of position problem; 2. After changing the locking plate to a split type, when the clamping corner is worn, only the movable clamping corner needs to be replaced, which saves spare parts cost and maintenance manpower. It only takes 1 hour to replace a set (4) of clamping corners separately, and only 0.5 hour when selectively replacing the clamping corners with excessive wear. It avoids the problem that when the clamping corners of the locking plate are worn and the whole locking plate is not replaced in time, and the large gap between the clamping corners and the AGC cylinder causes the fixing cylinder to fail, resulting in the running-out of position problem of the AGC. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is the front view structural schematic diagram of the present invention; Figure 2 is the top view structural schematic diagram of the present invention; Figure 3 is the side view structural schematic diagram of the present invention. EMBODIMENTS

[0009] A method for preventing the AGC steel of the finishing mill from running out of position, as Figure 1 、 2As shown in Figure 3, it includes an AGC hydraulic cylinder 1 with a locking plate 5, and a movable angle plate 6 is installed on both sides of the inner side of the locking plate 5 by bolts. Anti-runaway blocks 4 that are consistent with the appearance of the cylinder body are installed on both sides of the upper part of the cylinder body of the AGC hydraulic cylinder, and are fixed to the upper end surface of the middle and upper part of the cylinder body by bolts to ensure that the angles on both sides of the locking plate will not be separated from the AGC cylinder body when the AGC cylinder is placed in a low position; the inner side ends of the movable angle plate 6 are respectively against the ends of the anti-runaway blocks 4. In the figure, serial number 3 is the center line of the archway, and serial number 2 is the archway.

Claims

1. A method for preventing AGC steel from running out of position in a finishing mill, comprising an AGC hydraulic cylinder with a locking plate, Its characteristics are: An active angle plate is installed on both sides of the inner end of the locking plate by bolts, and anti-runaway blocks consistent with the shape of the cylinder body are installed on both sides of the upper part of the cylinder body of the AGC hydraulic cylinder, which are fixed to the upper end surface of the middle and upper part of the cylinder body with bolts to ensure that the angles on both sides of the locking plate will not separate from the AGC cylinder body when the AGC cylinder is placed in a low position; the inner ends of the active angle plate are respectively abutted against the ends of the anti-runaway blocks.

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