Operation method for improving width precision of hot-rolled trimming coil

Abstract

The invention discloses an operation method for improving the width precision of a hot-rolled trimming roll, which comprises the following steps of: firstly, determining a width zero position by taking a lower blade notch of a circle shear as a reference, and carrying out zero position calibration on a sensor; secondly, according to a set rule, the distance between cutting openings of lower blades of the disc shears on the two sides is adjusted to be consistent with the target width of a to-be-trimmed roll. And after the distance is adjusted in place, the circle shear is locked and fixedly stopped on the movable track. And before the strip steel enters the circle shear to be bitten, the middle compression roller in the circle shear area is controlled to be pressed down. And finally, after trimming is completed, the disc shear middle pressing roller is controlled to reset, and the machining operation of the trimming roll is completed. According to the method, the error during trimming is effectively improved, the trimming width precision control capability is improved, trimming roll positive tolerance control is achieved, and the user requirement is met.

Description

Technical Field

[0001] The present invention is mainly used in the technical field of the leveling and trimming production line in the hot rolling finishing area, and specifically relates to an operation method for improving the width accuracy of hot rolled trimmed coils. Background Art

[0002] Generally speaking, the delivery width of hot rolled trimmed coils is controlled according to positive tolerances. For example, when the strip width is less than 1.2 m, the required width tolerance is 0 - 3 mm, and when the strip width is between 1.2 m and 1.6 m, the required width tolerance is 0 - 5 mm. Therefore, in order to ensure that the width tolerance of the trimmed coil is controlled according to positive tolerances, the usual practice is to enlarge the target width by 1 - 2 mm. However, various errors may occur in actual production, and the accumulation of multiple errors may affect the target width of the final trimmed coil to fluctuate beyond the width tolerance range, resulting in unqualified products. The errors that may occur in the current production process are as follows.

[0003] 1. Due to the action of the shearing force of the rotary shear on the strip edges, the two sides of the strip will bend downwards and the middle will arch upwards, resulting in a "turtle back" phenomenon in the section from the rotary shear to the coiler during tensioning, making the actual strip width 1 - 2 mm larger than the target width.

[0004] 2. For strips with different thicknesses and strengths, the side clearance values (the clearance between the two side surfaces of the upper and lower shear blades) of the rotary shear are also different, and the side clearance values will also cause the actual width to be 0.5 - 1.6 mm larger than the target width.

[0005] 3. The errors of the equipment system itself, such as the clearance fit between components in the width adjustment mechanism of the rotary shear, the accuracy of sensors, and the assembly accuracy of the rotary shear blades. Summary of the Invention

[0006] The purpose of the present invention is to provide an operation method for improving the width accuracy of hot rolled trimmed coils. Through this operation method, positive tolerance control of the strip width can be ensured.

[0007] In order to achieve the above purpose, the present invention adopts the following technical solutions: An operation method for improving the width accuracy of hot rolled trimmed coils, characterized by including the following steps: S1: Taking the distance between the cutting edges of the lower blades of the two-sided rotary shear as the reference, set the zero position of the width adjustment of the rotary shear, and regularly calibrate the zero position of the sensor; S2: Let the distance between the cutting edges of the lower blades of the two-sided rotary shear be X mm, and the target width of the trimmed coil be W mm. During production operations, execute according to the following rules: a. When X - W ≥ 30 mm, control the two-sided rotary shear to move towards each other to reduce the distance between them until X = W and then stop; b. When X - W < 30 mm, first control the two side disk shears to move away from each other until X ≥ W + 30 mm, then control the two side disk shears to move towards each other until X = W and stop. S3: After the spacing adjustment is in place, control the two side disk shears to lock and fix them in place on the moving track. S4: Before the strip steel enters the disk shears to bite the steel, control the middle pressure roller in the disk shear area to lower. S5: After the edge trimming is completed, control the middle pressure roller of the disk shear to reset and complete the processing operation of this trimmed coil.

[0008] Further, a mechanical stop is set on the moving track. When the disk shear moves to the position where it contacts the mechanical stop, the disk shear is just at the zero position of the width adjustment. During the daily production operation, when it is detected that there is a gap between the disk shear and the mechanical stop contact surface and the gap width exceeds 0.1 mm, zero calibration of the sensor is required.

[0009] Further, a sensor for monitoring the distance of the gap is installed on the mechanical stop. When the detected gap width exceeds 0.1 mm, the corresponding sound and light alarm is controlled by the PLC to alarm, prompting the operator to calibrate the sensor.

[0010] The beneficial effects of the present invention: The operation is simple. First, calibrate the sensor to ensure that the accuracy of the sensor meets the requirements, and then adjust the distance between the cutting edges of the lower blades of the two side disk shears from large to small to the target width, which is beneficial to reducing the equipment accuracy error. At the same time, before the strip steel enters the disk shears to bite the steel, control the middle pressure roller of the disk shear to press down and hold the strip steel, ensuring that the strip steel is in a flat state during edge trimming, eliminating the situation where the width is too large due to the "turtle back" phenomenon during edge trimming, and further improving the edge trimming width control accuracy.

[0011] By using the method of the present invention, the width accuracy deviation can be controlled within 0 - 1 mm, ensuring that the strip steel width realizes positive tolerance control, meeting the user requirements, and having extremely high promotion value.

[0012] In addition, by setting a mechanical stop in the present invention, it is only necessary to check and measure the gap between the mechanical stop and the disk shear to calibrate the sensor conveniently and quickly. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be further described in detail below with reference to the accompanying drawings.

[0014] Figure 1 It is a schematic structural diagram of the disk shear equipment in the present invention.

[0015] Figure 2 It is a state diagram of the disk shear moving to the mechanical stop for zero calibration in the present invention.

[0016] Figure 3 Schematic diagram for adjusting the target width during the production process using the method of the present invention.

[0017] Figure 4 State diagram of the two-sided circular shears moving away from each other during the production process using the method of the present invention.

[0018] Figure 5 State diagram of the two-sided circular shears moving towards each other during the production process using the method of the present invention.

[0019] Figure 1 In the figure, 1 - mechanical stop, 2 - main mechanism of the circular shear, 3 - upper shear blade, 4 - intermediate pressure roller, 5 - intermediate transition roller, 6 - lower shear blade. Specific embodiments

[0020] The present invention will be further described in detail below with reference to the accompanying drawings.

[0021] An operation method for improving the width accuracy of hot-rolled trimmed coils according to the present invention is carried out according to the following steps.

[0022] Step 1: Taking the distance between the cutting edges of the lower blades of the two-sided circular shears as the reference, set the zero position of the width adjustment of the circular shear, and regularly calibrate the zero position of the sensor. Specifically, the zero position of the width adjustment of the circular shear is the distance between the cutting edges of the lower blades of the two-sided circular shears. According to the actual situation, a dimension larger than the width of the trimmed coil can be defined, such as Figure 2 As shown, 2250 mm is used as the dimension of the width adjustment zero position.

[0023] Preferably, a mechanical stop can be set on the moving track of the circular shear. When the circular shear moves to the position in contact with the mechanical stop, at this time, the circular shear is just at the width adjustment zero position; during the daily production operation, when it is monitored that there is a gap between the contact surface of the circular shear and the mechanical stop and the width of the gap exceeds 0.1 mm, the zero position calibration of the sensor needs to be carried out to ensure that the sensor accuracy meets the requirements.

[0024] Step 2: Let the distance between the cutting edges of the lower blades of the two-sided circular shears be X mm, and the target width of the trimmed coil be W mm. During the production operation, the following rules are executed.

[0025] a. When X - W ≥ 30 mm, control the two-sided circular shears to move towards each other, that is, as Figure 3 shown, the left circular shear moves in the A1 direction, and the right circular shear moves in the A2 direction, slowly reducing the distance between the two until X = W and then stop.

[0026] b. When 0 < X - W < 30 mm or X - W < 0, first control the two-sided circular shears to move away from each other, that is, as Figure 4As shown, the left disk shear moves in the B1 direction, and the right disk shear moves in the B2 direction, slowly pulling apart the distance between the two. When X ≥ W + 30 mm, then control the two disk shears to move towards each other, that is, as Figure 5 shown, the left disk shear moves in the C1 direction, and the right disk shear moves in the C2 direction until X = W and then stops.

[0027] C. When X = W, no adjustment is required and production can continue.

[0028] According to the above rules, in the actual production process, first: if the width of the currently processed trimmed coil is 1800 mm and the target width of the next trimmed coil is also 1800 mm, that is, X = W, no adjustment is required. Second: if the width of the currently processed trimmed coil is 1500 mm (i.e., the distance X = 1500 mm) and the target width W of the next trimmed coil is 1900 mm, after calculation, X - W < 0, execute according to method b. Third: if the width of the currently processed trimmed coil is 1500 mm (i.e., the distance X = 1500 mm) and the target width W of the next trimmed coil is 1480 mm, after calculation, X - W < 30 mm, still execute according to method b. Fourth: if the width of the current coil is 2100 mm (i.e., the distance X = 2100 mm) and the width of the next coil is 1600 mm, after calculation, X - W > 30 mm, then it is necessary to execute according to method a, and execute a and b.

[0029] Using the method of the present invention, the distance between the two disk shears is always adjusted to the trimmed target width in the direction from the larger width to the smaller width. In this way, the clearance error between the equipment components can always be controlled in one direction, ensuring that the strip width realizes positive tolerance control.

[0030] Step three: After the distance between the two disk shears is adjusted in place, control the two disk shears to lock and fix them on the moving track to avoid misoperation.

[0031] Step four: Before the strip enters the disk shear to bite the steel, control the intermediate pressure roller in the middle area between the two disk shears to press down to press the strip, ensuring that the strip is in a straight state during trimming, eliminating the situation where the width is too large due to the occurrence of the "humpback" phenomenon during trimming, and further improving the trimming width control accuracy.

[0032] Step five: After trimming is completed, control the intermediate pressure roller of the disk shear to reset to complete the processing operation of this trimmed coil. Wait for the next trimmed coil to be processed and repeat step two.

[0033] Preferably, in order to calibrate the sensor more promptly, a sensor for monitoring the distance of the gap may be installed on the mechanical stop. When the detected gap width exceeds 0.1 mm, the corresponding audible and visual alarm is controlled by the PLC to give an alarm, prompting the operator to calibrate the sensor. At the same time, the gap width value can also be displayed on the HMI screen for the operator to make a comprehensive judgment.

[0034] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for improving the width accuracy of hot-rolled trimmed coils, characterized in that: The steps include: S1: Set the zero position of the width adjustment of the circular shears based on the distance between the cuts of the blades of the circular shears on both sides, and calibrate the zero position of the sensor regularly; S2: Assume that the distance between the cuts of the two discs is X mm, and the target width of the trimmed roll is W mm. During production, follow the following rules: a. When XW≥30mm, control the disc shears on both sides to move towards each other and reduce the distance between them until X=W; b. When XW<30mm, first control the disc shears on both sides to move in opposite directions until X≥W+30mm, then control the disc shears on both sides to move in opposite directions until X=W; S3: After the spacing is adjusted to the right position, the disc shears on both sides are locked and fixed on the moving track; S4: Before the strip enters the disc shear to bite the steel, the middle roller in the disc shear area is controlled to press down; S5: After the trimming is completed, the middle pressure roller of the disc shear is controlled to reset to complete the processing of the trimming roll.

2. The method for improving the width accuracy of hot-rolled trimmed coil according to claim 1, characterized in that: A mechanical stop is set on the moving track. When the disc shear moves to the position in contact with the mechanical stop, the disc shear is just at the zero position of width adjustment. In daily production operations, when it is detected that there is a gap between the contact surface of the disc shear and the mechanical stop and the gap width exceeds 0.1mm, the sensor needs to be calibrated at the zero position.

3. The method for improving the width accuracy of hot-rolled trimmed coil according to claim 2, characterized in that: A sensor for monitoring the distance of the gap is installed on the mechanical stop. When the detected gap width exceeds 0.1 mm, the PLC controls the corresponding sound and light alarm to sound an alarm, prompting the operator to calibrate the sensor.

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