TW202342195A - Method for reducing edge warping diff of cold rolled steel coil - Google Patents

Abstract

A method for reducing warping diff of cold rolled steel coil is provided. The method incudes a preparation step, a cold rolling step, a detection step, a determination step, and a feedback step, wherein an edge drop detector is used to detect and determine an edge warping diff of the coil, and then adjust the speed of work rolls of a cold rolling mill through a controller, thereby reducing the edge warping diff of the coil.

Description

Methods to reduce edge warping of cold-rolled steel coils

The present invention relates to a method for reducing the amount of edge warping of cold-rolled steel coils, and in particular, to a method for reducing the amount of edge warping of cold-rolled steel coils using an edge drop detector for detection, calculation and result judgment.

The steel industry is the mother of industry. Daily necessities, construction, equipment and machines in the automation industry all use steel. The manufacturing process of steel products is generally based on the production of different types of steel and iron raw materials by steel plants, such as Steel plates, iron pipes, etc., and after downstream manufacturing plants purchase raw materials from steel plants, they then continue to use stamping, through-holes, grinding and other processing methods to form the final products.

The existing manufacturing method of cold-rolled steel coils includes the following steps in sequence: hot rolling a steel blank to form a steel strip, then pickling and trimming the hot-rolled steel strip, and then pickling the steel strip. The steel strip subjected to trimming operation is subjected to cold rolling operation, then the steel strip subjected to cold rolling operation is annealed, then the steel strip subjected to annealing operation is subjected to quenching and tempering operation, and finally the quenched and tempered steel strip is The strip is subjected to finishing operations to produce a cold-rolled steel coil.

In cold rolling operations, when the edges of steel coils are warped, the work rolls of the cold rolling mill are usually replaced. However, sometimes after rolling several steel coils after replacing the work rolls, steel coils will still be produced. If the edge of the coil is warped, the work roll must be replaced. This method not only wastes the raw material cost and operation time of replacing the work roll, but also will be rejected after the entire steel coil is produced because of the warped edge of the steel coil.

Therefore, in order to overcome the shortcomings and deficiencies in the prior art, it is necessary for the present invention to provide an improved method for reducing the amount of edge warping of cold-rolled steel coils, so as to solve the problems existing in the above-mentioned conventional technologies.

The main purpose of the present invention is to provide a method for reducing the amount of edge warping of cold-rolled steel coils, by detecting the edge drop values at two calibrated distances on the sides of the steel coil, and calculating the difference between the two edge drop values. Determine the steel coil edge warping, thereby reducing the occurrence of steel coil edge warping on the discharging side of the cold rolling mill or reducing the amount of steel coil edge warping, so as to reduce the risk of steel coil edge warping. The rejection rate caused by this.

In order to achieve the above purpose, the present invention provides a method for reducing the amount of edge warping of cold-rolled steel coils. The method includes a preparation step, a cold rolling step, a detection step, a judgment step and a feedback step; in the preparation step , a cold rolling mill, an edge drop detector and a controller are provided. The cold rolling mill has multiple work rolls. The edge drop detector is installed on a discharge side of the cold rolling mill. The controller electronically The cold rolling mill and the edge drop detector are permanently connected; in the cold rolling step, the controller drives the work roll of the cold rolling mill to rotate to cold-roll a steel coil, so that the steel coil moves toward the discharging side. Move; in the detection step, the edge drop detector is used to detect a main calibration edge drop value from at least one side of the steel coil inward by a main calibration distance and from at least one side of the steel coil. Detect the secondary calibration edge drop value while shrinking inward at a calibration distance, and then find a first difference between the main calibration edge drop value and the secondary calibration edge drop value, and send it back to the controller; In this judgment step, the controller is used to judge the first difference. When the first difference is greater than A, that is, a judgment result of the controller is that the edge of the steel coil is warped. When the first difference is less than -A, that is, the judgment result is that the edge of the steel coil is not warped, where A is a natural number; in this feedback step, when the judgment result is that the edge of the steel coil is warped, the controller will control the cold rolling mill The work roll of the cold rolling mill is reduced below a limited speed. When the judgment result is that the edge of the steel coil is not warped, the controller will control the work roll of the cold rolling mill to cancel the limited speed.

In one embodiment of the present invention, in the detection step, a main calibration edge drop value is detected by using the edge drop detector to retract a main calibration distance from the two sides of the steel coil and The two sides of the steel coil are retracted inwards by a calibration distance to detect the drop value of one calibration side, and then the drop value of the main calibration side and the drop value of the secondary calibration side corresponding to the two sides of the steel coil are respectively obtained. A first difference value and a second difference value of the edge drop value are calibrated and sent back to the controller.

In one embodiment of the present invention, in the judgment step, the controller is used to judge the first difference and the second difference. When the first difference or the second difference is greater than A, that is, the first difference or the second difference is greater than A. The judgment result of the controller is that the edge of the steel coil is warped. When the first difference value and the second difference value are both less than -A, the judgment result is that the edge of the steel coil is not warped.

In one embodiment of the present invention, in the judgment step, when the first difference or the second difference is greater than 1 μm, and the state of the first difference or the second difference remains for more than 1 second, that is, the The controller's judgment result is that the edge of the steel coil is warped.

In one embodiment of the present invention, in the determination step, when both the first difference value and the second difference value are less than -1 μm, and the state of the first difference value or the second difference value remains for more than 200 seconds, That is, the judgment result is that the edge of the steel coil is not warped.

In an embodiment of the present invention, in the detection step, the secondary calibration distance is greater than the main calibration distance.

In one embodiment of the present invention, in the feedback step, when the judgment result is that the edge of the steel coil is warped, the controller will send a warning message.

In one embodiment of the present invention, in the feedback step, the limited rotation speed is 300 meters/minute.

In one embodiment of the present invention, in the cold rolling step, the controller drives the work rolls of the cold rolling mill to rotate so that the rolling speed of the cold rolling mill is 50 to 850 meters/minute.

In one embodiment of the present invention, in the cold rolling step, the discharge thickness of the steel coil is less than 1 mm.

As mentioned above, the edge drop detector is used to continuously detect the edge drop value at two calibrated distances on the sides of the steel coil, and calculate the difference between the two side drop values to determine the steel coil. Whether the edge of the steel coil is warped, and then the controller can be used to control the limited speed of the work roll of the cold rolling mill when the edge of the steel coil is warped, and when the edge of the steel coil is not warped, the controller can be used to control Cancel the limited rotation speed of the work roll of the cold rolling mill, thereby reducing the occurrence of steel coil edge warping on the discharge side of the cold rolling mill or reducing the amount of steel coil edge warping, so as to reduce the risk of the steel coil The rejection rate caused by warping of the edge of the steel coil is reduced, and the raw material cost and operation time of replacing the work roll are saved.

In order to make the above and other objects, features, and advantages of the present invention more apparent and understandable, embodiments of the present invention will be described in detail below along with the accompanying drawings. Furthermore, the directional terms mentioned in the present invention include, for example, up, down, top, bottom, front, back, left, right, inside, outside, side, peripheral, central, horizontal, transverse, vertical, longitudinal, axial, Radial, uppermost or lowermost, etc., are only directions with reference to the attached drawings. Therefore, the directional terms used are to illustrate and understand the present invention, but not to limit the present invention.

Please refer to Figure 1, which is a method for reducing the amount of edge warping of cold-rolled steel coils according to an embodiment of the present invention. The method includes a preparation step S201, a cold rolling step S202, a detection step S203, and a judgment step. S204 and a feedback step S205. The present invention will describe the relationship between each step and its operating principle in detail below.

Please refer to Figures 1, 2 and 3. In the preparation step S201, a cold rolling mill 101, a side drop detector 102 and a controller 103 are prepared. The cold rolling mill 101 has a plurality of work rolls 104. , the edge drop detector 102 is disposed on a discharging side of the cold rolling mill 101 , and the controller 103 is electrically connected to the cold rolling mill 101 and the edge drop detector 102 .

Continuing to refer to Figures 1, 2 and 3, in the cold rolling step S202, the controller 103 drives the work roll 104 of the cold rolling mill 101 to rotate to cold-roll a steel coil 105, so that the steel coil 105 Move to the discharging side. In this embodiment, the controller 103 drives the work roll 104 of the cold rolling mill 101 to rotate, so that the rolling speed of the cold rolling mill 101 is 50 to 850 meters/minute, and the discharge thickness of the steel coil 105 is Below 1 mm, preferably, the rolling speed of the cold rolling mill is 400 to 800 meters/minute.

Continuing to refer to FIGS. 1 , 3 and 4 , in the detection step S203 , the edge drop detector 102 continuously removes the steel coil 105 from at least one side (for example, the right side) of the steel coil 105 on the discharging side. edge) shrinks inward by a main calibration distance D1 (i.e. P1) to detect the drop value of a main calibration edge and shrinks inward from at least one side (such as the right side) of the steel coil 105 by a calibration distance D2 (i.e. P2) Detect the secondary calibration edge drop value, and then find a first difference between the main calibration edge drop value and the secondary calibration edge drop value (that is, the main calibration edge drop value minus the secondary calibration edge drop value) difference) and sent back to the controller 103. Specifically, the secondary calibration distance D2 (for example, 15 mm) is greater than the main calibration distance D1 (for example, 5 mm).

In this embodiment, the edge drop detector 102 is used to detect a main calibration edge drop value from two sides of the steel coil 105 (for example, the left side and the right side) inward by a main calibration distance D1. (For example, the main calibration side drop value on the left side and the main calibration side drop value on the right side) and the two sides of the steel coil 105 (such as the left side and the right side) are respectively retracted inward by a calibration distance D2 to detect Measure the drop value of the secondary calibration side (for example, the drop value of the secondary calibration side of the left variable side and the drop value of the main calibration side of the secondary side), and then calculate the drop value of the main calibration side of the two sides corresponding to the steel coil 105. A first difference (difference of the left side) and a second difference (difference of the right side) from the sub-calibration side are sent back to the controller 103 .

Please refer to Figure 1, Figure 2 and Figure 3. In the judgment step S204, the controller 103 is used to judge the first difference. When the first difference is greater than A, that is, a value of the controller 103 is The judgment result is that the edge of the steel coil is warped. When the first difference is less than -A, the judgment result is that the edge of the steel coil is not warped, where A is a natural number.

In this embodiment, the controller 103 is used to judge the first difference and the second difference. When the first difference or the second difference is greater than A, the judgment result of the controller 103 is The edge of the steel coil is warped. When the first difference value and the second difference value are both less than -A, the judgment result is that the edge of the steel coil is not warped. Specifically, when the first difference or the second difference is greater than 1 μm, and the state of the first difference or the second difference is maintained for more than 1 second, the controller 103 determines that the edge of the steel coil is cocked. When the first difference value and the second difference value are both less than -1µm, and the state of the first difference value or the second difference value is maintained for more than 200 seconds, the judgment result is that the edge of the steel coil is not warped.

Continuing to refer to Figures 1 and 2, in the feedback step S205, when the judgment result is that the edge of the steel coil is warped, the controller 103 will control the work roll 104 of the cold rolling mill 101 to reduce it to below a limited speed. , when the judgment result is that the edge of the steel coil is not warped, the controller 103 will control the work roll 104 of the cold rolling mill 101 to cancel the limited rotation speed. In this embodiment, when the judgment result is that the edge of the steel coil is warped, the controller 103 will send out a warning message by using a buzzer to sound or display it through the display, and the limited rotation speed is 300 meters/meter. minute.

As mentioned above, the edge drop detector 102 is used to continuously detect the edge drop value at two calibrated distances on the side of the steel coil 105, and calculate the difference between the two side drop values to determine the edge drop value. Whether the edge of the steel coil 105 is warped, and then the controller 103 can be used to control the limited rotation speed of the work roll 104 of the cold rolling mill 101 when the edge of the steel coil is warped, and when the edge of the steel coil is not warped. , the controller 103 is used to cancel the limited rotation speed of the work roll 104 of the cold rolling mill 101, thereby reducing the edge warping of the steel coil 105 on the discharge side of the cold rolling mill 101 or reducing the number of steel coils. The amount of edge curling is to reduce the rejection rate of the steel coil 105 caused by the edge curling of the steel coil, and save the raw material cost and operation time of replacing the work roll.

Although the present invention has been disclosed through embodiments, they are not intended to limit the present invention. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection of the present invention is The scope shall be determined by the appended patent application scope.

101:Cold rolling mill 102: Edge drop detector 103:Controller 104:Working roller 105:Steel Coil D1: main calibration distance D2: Secondary calibration distance P1: at the main calibration distance of retraction P2: Calibration distance of the retraction pair S201: Preparation steps S202: Cold rolling step S203: Detection step S204: Judgment step S205: Feedback step

Figure 1 is a flow chart of a method for reducing edge warping of cold-rolled steel coils according to an embodiment of the present invention. FIG. 2 is a schematic diagram of a cold rolling mill and an edge drop detector configured according to a method for reducing edge warping of cold-rolled steel coils according to an embodiment of the present invention. Figure 3 is a schematic diagram of signal transmission between a cold rolling mill, an edge drop detector and a controller for a method of reducing edge warping of cold-rolled steel coils according to an embodiment of the present invention. Figure 4 is a schematic diagram of setting the main calibration distance and the secondary calibration distance of the steel coil according to a method of reducing the edge warping amount of cold-rolled steel coils according to an embodiment of the present invention.

S201: Preparation steps

S202: Cold rolling step

S203: Detection step

S204: Judgment step

S205: Feedback step

Claims (10)

A method to reduce the amount of edge warping of cold-rolled steel coils, including: A preparation step is to prepare a cold rolling mill, an edge drop detector and a controller. The cold rolling mill has multiple work rolls. The edge drop detector is installed on a discharge side of the cold rolling mill. The control The device is electrically connected to the cold rolling mill and the edge drop detector; In a cold rolling step, the controller drives the work roll of the cold rolling mill to rotate to cold roll a steel coil, so that the steel coil moves to the discharge side; A detection step, using the edge drop detector to detect a main calibration edge drop value at a main calibration distance from at least one side of the steel coil and shrinking from at least one side of the steel coil. Detect the secondary calibration edge drop value at the secondary calibration distance, then calculate a first difference between the primary calibration edge drop value and the secondary calibration edge drop value, and transmit it back to the controller; A judgment step is to use the controller to judge the first difference. When the first difference is greater than A, that is, a judgment result of the controller is that the edge of the steel coil is warped. When the first difference is less than - A, that is, the judgment result is that the edge of the steel coil is not warped, where A is a natural number; and A feedback step. When the judgment result is that the edge of the steel coil is warped, the controller will control the work roll of the cold rolling mill to reduce below a limited speed. When the judgment result is that the edge of the steel coil is not warped, The controller will control the work roll of the cold rolling mill to cancel the limited rotation speed. The method for reducing the amount of edge warping of cold-rolled steel coils as described in claim 1, wherein in the detection step, the edge drop detector is used to shrink inwards a main calibration distance from the two sides of the steel coil. Detect the drop value of a main calibration edge at a calibration distance and detect the drop value of a calibration edge at a calibration distance from the two sides of the steel coil, and then calculate the two sides of the steel coil respectively. A first difference and a second difference between the main calibration edge drop value and the secondary calibration edge drop value are returned to the controller. The method for reducing the amount of edge warping of cold-rolled steel coils as described in claim 2, wherein in the judgment step, the controller is used to judge the first difference and the second difference. When the first difference Or the second difference value is greater than A, that is, the controller determines that the edge of the steel coil is warped. When the first difference value and the second difference value are both less than -A, that is, the judgment result is that the edge of the steel coil is not warped. rise. The method for reducing edge warping of cold-rolled steel coils as described in claim 3, wherein in the judgment step, when the first difference or the second difference is greater than 1 μm, and the first difference or the second difference If the value state remains for more than 1 second, that is, the controller determines that the edge of the steel coil is warped. The method for reducing edge warping of cold-rolled steel coils as described in claim 3, wherein in the judgment step, when the first difference and the second difference are both less than -1µm, and the first difference or the third difference If the difference between the two values is maintained for more than 200 seconds, the judgment result is that the edge of the steel coil is not warped. The method for reducing edge warping of cold-rolled steel coils as described in claim 1, wherein in the detection step, the secondary calibration distance is greater than the main calibration distance. The method of reducing the amount of edge warping of cold-rolled steel coils as described in claim 1, wherein in the feedback step, when the judgment result is that the edge of the steel coil is warped, the controller will send a warning message. The method for reducing edge warping of cold-rolled steel coils as described in claim 1, wherein in the feedback step, the limited rotation speed is 300 meters/minute. The method for reducing edge warping of cold rolled steel coils as described in claim 1, wherein in the cold rolling step, the controller drives the work roll of the cold rolling mill to rotate so that the rolling speed of the cold rolling mill is between 50 and 50 850 meters/minute. The method for reducing edge warping of cold-rolled steel coils as described in claim 1, wherein in the cold-rolling step, the thickness of the steel coil is less than 1 mm.

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