JPS6277110A - Dimension and shape straightening apparatus for hot rolling steel plate - Google Patents

Abstract

PURPOSE:To improve dimensional accuracy and shape quality of steel plates by disposing a plate thickness meter and a plate width meter at the outlet side of the final stand of a finishing rolling mill and installing a dimension straightening rolling mill and a tension adding device at the downstream side of the above instruments. CONSTITUTION:A plate thickness meter 12, a plate width meter 14, camber meter 16, plate crown meter 18, and shape detector 20 are disposed at the outlet side of the final stand 10A of a hot finishing rolling mill 10. A straightening rolling mill 24 and a tension adding device 26 are installed at the downstream side of those instruments. The plate thickness meter 12 measures a thickness of a strip 11 and the rolling mill 24 is subjected to a feedforward control in correspondence with a deviation between the measured value and the target plate thickness. Then, a plate width, camber, and plate shape are subjected to a feedforward control in the same manner through the rolling mill 24 or the device 26. In this method, dimensional accuracy and shape quality are im proved over the entire length of the strip 11.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a hot rolling W4 root size and shape correction equipment. [Prior art] In a hot continuous plate rolling mill (hot strip mill),
Improving the dimensional accuracy of rolled materials is essential from the viewpoint of improving product yield and quality, and various techniques have been developed. Items subject to judicial and shape control in hot strip mills can be roughly divided into five types: plate thickness, plate width, -crown, main thickness, and shape. The plate thickness control is intended to reduce variations in plate thickness in the longitudinal direction of the strip, and an example of the shape of the strip 1 when this plate thickness control is defective is shown in FIG. 2 (A>). Plate width control is intended to reduce the variation in the strip width in the longitudinal direction of the strip, and an example of the shape of the strip 1 when this width control is poor is shown in Fig. 2 (B). Crown control iλ The opening is for reducing the change in thickness in the longitudinal direction of the strip or controlling it to a predetermined lln, and the strip 1 when this crown tll lit is defective.
An example of the shape is shown in FIG. 2(C). Camber control reduces the bending in the longitudinal direction of the strip, and an example of the shape of the strip 1 when the camber control is poor is shown in Fig. 2 (D). An example of the shape of the strip 1 when this shape control is defective is shown in FIG. 2 ([). Various types of ii+ control devices for controlling each of the above-mentioned items have been developed and put into practical use. Additionally, sensors that measure dimensional defects in the five scale items mentioned above have been developed and have been put into practical use. On the other hand, as shown in Fig. 3, a typical hot strip mill has a configuration including 1 to 6 rough rolling mills, 5 to 7 rolling mills, It is constructed by sequentially arranging two to five drinking bowls 5, and various controls are executed to achieve the dimensional accuracy of the above five items. In addition, the number 6 in the figure is a measuring instrument for correcting plate thickness, plate width, etc. For example, in the method for improving plate crown accuracy mentioned above,
A plate crown control method has been proposed as shown in Japanese Patent Application Laid-Open No. 57-25214. This plate crown control method includes installing a rounded round system tIIti structure consisting of a light reduction stand, a hot leveler, and a vinyl roll on the line downstream of the final stand of the hot soil pressure low line; Using a variable crown roll, the temporary crown is controlled by selectively changing the roll crown and the roll reduction ratio, and the steel strip that has passed through the light reduction stand is immediately changed into a shape μ by the hot leveler. 11. The invention is characterized in that a constant tension is maintained by the pinch rolls against the strain (1) passing through the light reduction stand and the hot leveler. According to this method, the plate crown thickness can be reduced over the entire length of the strip.

[Problems that the invention attempts to solve]

However, in the conventional hot strip mill, the final stand 17 that controls the shape and dimensions as described above is usually the final stand 3A of the finishing mill 3, and dimensional defects may occur downstream of this final stand. Even if this occurs, there is generally no functionality to correct it. On the other hand, in order to improve product yield, it is necessary to have good cutting marks over the entire length of the rolled material. When you look,
Finishing rolling 1: Although the single hole capacity of the hardware for u is capable of controlling the size and shape as described above, the various measuring instruments 6 are placed downstream of the final finishing stand. Therefore, even if the cutting method is poor at the leading edge of the strip, it is normal that t3 is not positive at all. Alternatively, the dimensions may change after measurement. Below, we will specifically explain each of the 19 items of the system i1[1]. Regarding the accuracy, the plate thickness is measured using a flat plate thickness meter at the exit side of the final stand, and the difference between this actual plate thickness measurement and the plate thickness target value is calculated.
Find the i difference and finish rolling the board thickness control 0 base based on the deviation 1
Although ffi'll is performed by feeding back to the lower position, since the leading edge of the strip has already passed the final stand, it is impossible to change the thickness. Furthermore, even when measuring the plate thickness between finishing stands, the time required to transfer the tip of the strip between finishing stands is extremely short, approximately 0.5 to 1°0 sec/SLd! Therefore, there is a problem in that it is difficult to control the thickness of the leading edge of the strip. Regarding strip width accuracy, when measuring with a strip width meter at the exit side of the final stand, the strip width decreases due to the tension between the final stand and the winder after measurement. -ru. Also, in some cases, a sheet width meter is placed just before the counting machine at the 1ζ point to improve the J11 constant accuracy, but in this case, it is impossible to control the sheet width in terms of product INi only by measuring. It has a certain point. Furthermore, in either case, there is a problem in that it is impossible to control the strip width a1 at the end of the strip. Regarding the crown 1ill and 1fIl, there is a problem in that the tip of the strip cannot be reprimanded because it is measured using a crown meter at the exit side of the final stand. Also, even when measuring the crown between stands, the transfer time of the tip between finishing stands is very short, about 0.5 to 1.0 sec/std, as in the case of the plate thickness 1iIJ lit. Therefore, there is a problem in that it is difficult to actively perform crack-more correction from the tip of the strip downstream of the sensor.As for camber control, measurements are taken between the stands of the finishing mill. It is very difficult to measure the camber at 4T after the final stand of finishing rolling, which leads to the problem that it is impossible to control the camber correction from the tip of the strip.Shape For control, stand exit of finishing rolling mill!11
The shape of the tip of the strip can be controlled/
I-I will list the problems that are difficult. In addition, it is normal for the shape to change during cooling in the cooling device installed downstream of the finishing roll, and even if the strip shape at the exit side of the finishing stand is controlled correctly, it will not be possible to obtain the highest It'% product. The problem is that good quality is not always guaranteed. Furthermore, there is a problem in that even if the shape is measured just before winding, it cannot be reflected in the shape correction control of the strip. As mentioned above, in conventional hot strip mills, the tip of the strip is determined depending on the accuracy of the mill setup for all ~J method accuracy factors. The problem is that it is not possible to improve the shape and dimensional accuracy of the tip of the strip. In addition, although the temporary crown control method proposed in JP-A-57-25214 can reduce the plate crown m over the entire length of the strip, as mentioned above, the plate crown m There is a problem in that the thickness, plate width, camber dimensions, and shape accuracy cannot be improved. Furthermore, high speed threading through the leveler becomes extremely difficult, making it impossible to effectively control the leading edge of the strip. Therefore, this control method has the problem that the shape of the tip of the strip cannot be effectively corrected. (Objective of the Invention 1) The present invention has been made to solve the above-mentioned conventional problems, and is a hot-rolled steel sheet that can be rolled into hot-rolled steel sheets with excellent rolling dimensional accuracy over the entire length and a good shape. The purpose is to provide size and shape correction equipment for steel plates.

[Means for Solving the Problems] The present invention provides a plate thickness gauge, a plate width gauge, a camber gauge 1, a temporary round gauge, and a shape detector installed on the exit side of the final stand of the hot rolling machine 11. , find the difference between the actual measurement value from each measuring device and each target value, and calculate the reduction control amount corresponding to the plate thickness, the tension control amount corresponding to the plate width difference, and the camber distance difference. During single-pressure king system, roll bending system 1211 that can cope with temporary crown deviation, roll benzo ink control that corresponds to steepness deviation [A calculator that affects each U and a +'rQ measuring instrument are installed on the downstream side. and a dimension straightening mill which is feedforward controlled by the rolling reduction control nu signal, single rolling control rTL signal, and roll bending control amount signal from the computing unit, and a dimension straightening mill installed on the exit side of the dimension straightening mill. and a tension applying device that is feed forward controlled by a tension control signal from the arithmetic unit. A plate thickness gauge, plate width gauge, camber gauge, plate crack gauge, and shape detector are installed on the exit side of the final stand of the finishing rolling mill, and the actual measured values from these measuring instruments are compared with each target value. Determine the deviation, and based on the control amount corresponding to the deviation, feed forward the dimensional correction pressure f and tension applying device installed downstream of the measuring device.
By doing so, a good accuracy of application can be obtained from the tip of the strip. As a result, it is possible to produce a hot-rolled steel plate that has an excellent rolling dimension 'V4 degree and a good shape in all respects.

【Example】

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the size and shape correction equipment for hot rolled steel sheets of the present invention will be described in detail below with reference to the drawings. In this embodiment, as shown in FIG. 1, hot finish rolling Bj11
Plate thickness gauge 12 installed on the exit side of the final stand IOA of 0
, board width total 14, camber total 16, board crown total 18,
Shape detector 20 and each measuring device 12.14.16.1
8. A comparator 21 that calculates the deviation between the actual measured value from 20 and each target value, a reduction control wheel that corresponds to the plate thickness deviation based on the deviation from the comparator 21, and a tension control that corresponds to the plate width deviation. amount, one side reduction control amount corresponding to the camber-Mfl difference, and roll bending control 1lfI corresponding to the plate crown deviation! , a calculator 22 for calculating the roll bending control amount corresponding to the steepness deviation, and the measuring device 1.
Installed downstream from 2.14.16.18.20,
Downward control m signal from the arithmetic unit 22, single downward control l1
ff! Dimensional straightening rolling mill 2 whose feed forward is controlled by signals and roll bending control furnace signals
4, and a tension applying device 26 which is installed on the exit side of the judicial straightening rolling mill 24 and is feedforward controlled by a tension control amount signal from the arithmetic unit 22. . The size straightening rolling mill 24 is a rolling mill capable of all of leveling reduction, crown control, and plate thickness control, and is therefore equipped with a reduction device 28 and a roll bending device 30. However, this judicial straightening mill 24 has only one purpose of dimensional correction, and is a small machine whose rolling capacity is 1/3 of that of normal finishing rolling. The tension applying device 1lff26 is for applying tension to the strip 11, and is configured before rolling. In addition, the code 32 in the figure is tfi dimension correction rolling ■24
and a tensioning device 26 and a motor driving the rolls. Further, 34 is a cooling device, and 36 is a winding device (indicates a winding device).Next, the operation of this embodiment will be explained.First, correction of the plate thickness error will be explained. ,'it 12
-Measure the thickness of the lip 11, use the comparator 21 to find the deviation between the actual measurement value from the thickness meter 12 and the target thickness, and calculate the thickness corresponding to the thickness deviation determined by the comparator 21 (7). Control
The i+m signal is calculated by 1'i by the calculating unit 22, and the rolling device 28 of the size straightening mill 24 is operated in a feedforward manner so as to correct the speed at which the plate thickness deviates from the target plate thickness based on the plate thickness control signal tl. This makes it possible to control the cutting edge of the strip, which was impossible in conventional hot rolling lines. Next, correction of the board width error will be explained. Finishing rolling mill 1
The width of the strip 11 is measured using a width agent 14 on the exit side of 0, and the deviation between the actual measurement value from the width meter 14 and the target width is determined by the comparator 21. The tension force 11 controller signal corresponding to the strip width deviation is Q-operated by the q operator 22, and the tension applying device 26 is feedforward controlled by the tension control signal t2I1 quintillion, thereby correcting the strip width. The tension applying device 26 is controlled by tracking the tension control amount signal using the calculator 22, and performing high tension rolling in areas where the width deviation is large and low tension rolling in areas where the deviation is small. It is. Next, crown correction will be explained. Kehi rolling mill 1
The plate crown is measured by the plate crown meter 16 on the exit side of 0, the deviation between the actual measurement value of the plate crown suspension and each target value is determined by the comparator 21, and the roll bending control amount corresponding to this plate crown deviation is determined. The calculation unit 22 calculates the roll bending from the calculation unit 22.
Crown correction is performed by feedforward controlling the roll pending force of the roll bending device 30 of the dimension correction rolling mill 24 using the m signal. Next, we will explain about camber correction (at the exit side of the t'-hirt extension part 10, we will measure the camber bar with a kisember meter 18 and one side gauge of the strip with a plate crown meter 16. In response to the one-side reduction control signal from the calculator 22, the reduction device 28 of the dimension correction rolling mill 24 is activated.
Camber correction is performed by controlling the amount of feed forward at the one-side lowered position. Next, shape correction will be explained. The shape is measured by the shape detector 20 at the exit side of the finish rolling 1 and 10, the deviation between the measured value and the target steepness is determined by the comparator 21, and the roll bending 1III machining signal corresponding to this deviation is calculated. The roll bending control amount signal is used to carry out feedforward control of the roll bending device 30 of the dimension correction rolling mill 24 to correct the shape. Therefore, according to this embodiment, the target size and shape can be controlled even at the tip end of the strip 11. As a result, it is possible to produce a hot-rolled steel sheet with excellent rolling dimensional accuracy and a good shape in terms of the entire length. In the above embodiment, the tension applying device 26 is constituted by a rolling mill. However, the present invention is not limited to this, and may be configured by, for example, a pinch roll.

【Effect of the invention】

As explained above, the present invention has the excellent effect of being able to produce 1 q of hot rolled steel plates with excellent rolling dimensional accuracy and good shape over the entire length.

[Brief explanation of drawings]

FIG. 1 is a side view showing an embodiment of the dimension and shape correction installation fi of a hot rolled steel plate according to the present invention, FIG. 2 is a plan view and a perspective view showing examples of various dimensional defects of the strip, Third
The figure is a side view showing the layout of a conventional hot strip mill. 10... Hot finishing rolling mill, 11... Strip, 12... Plate thickness gauge, 1
4... Board width meter, 16... Camber meter,
18... Plate crown meter, 20... Shape detector,
22... Arithmetic unit, 24... Dimension correction rolling machine, 26-... Tension applying device. Agent Kei Matsuyama Ya Cantaka Theory Figure 2!

Claims (1)

[Claims] (1) The plate thickness gage, plate width gage, camber gage, plate crown gage, and shape detection gage installed on the exit side of the final stand of the hot finishing rolling mill, and the actual measured values from each of the above-mentioned measuring instruments and their respective targets. The deviation from the value is calculated, and the amount of rolling control corresponding to the thickness deviation, the tension control amount corresponding to the sheet width deviation, the one-side rolling control amount corresponding to the camber amount deviation, the roll bending control amount corresponding to the sheet crown deviation, and the steepness control amount are calculated. a computing device that calculates each roll bending control amount corresponding to the degree deviation; and a computing device installed downstream of the measuring device, and receiving a rolling control amount signal, a single rolling control amount signal, and a roll bending control amount signal from the computing device. a dimensional straightening rolling machine that is feedforward controlled by a dimensional straightening rolling machine; and a tensioning device that is installed on the exit side of the dimensional straightening rolling machine and that is feedforward controlled by a tension control amount signal from the computing unit. Dimension and shape straightening equipment for hot rolled steel sheets, characterized by: