JPS5848248B2 - Steel plate continuous rolling equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to continuous rolling equipment that simultaneously and continuously controls offset and crown of a steel plate.

In continuous rolling of a steel plate, the steel plate may shift to either the left or right in the width direction during rolling, and this phenomenon is generally referred to as skewing.

When the degree of deviation exceeds a certain level, the steel plate comes into excessive contact with the side guides, causing buckling at the ends of the steel plate, which impedes smooth threading, resulting in defective rolling products and a decrease in yield. Not only was there a lot of waste, but it also took a long time to process defective products, reducing factory efficiency.

Conventionally, as a means to prevent this deviation of the steel plate, it has been done to adjust the amount of reduction on the drive side and work side of each stand, but the relationship between the amount of reduction adjustment and the amount of deviation correction is not clear, and It was difficult to make stable adjustments.

On the other hand, as a means of correcting the crown, which is one of the elements that define the profile of a steel plate, conventionally the thickness of each part of the steel plate in the width direction is actually measured after rolling, and based on this value, the operator adjusts the rolling pitch and adjusts the thickness of each stand. The solution was to adjust the rolling load distribution or adjust the rolling reduction on the rolling mill, drive side, and work side, but these methods require time to determine the actual measured values, making it difficult to quickly correct defective profiles. can't do it.

Moreover, changing the rolling load distribution has a negative effect on the plate temperature and plate thickness accuracy, adjusting the rolling pitch leads to a decrease in efficiency, and adjusting the rolling mill reduction has problems in terms of the rooting of the plate to the rolls. It is extremely difficult for an operator to take this into consideration and select the optimal value for each element with high accuracy.

In addition, as another means of obtaining the desired crown, prior to rolling, it has been conventionally practiced to grind the roll profile to obtain the desired crown, but as the amount of rolling increases, the roll profile The roll profile changes due to thermal expansion or wear, and there is a limit to the amount of roll that can be rolled per roll.

In order to improve the drawbacks of the conventional crown control method, methods for automatically controlling the crown using a computer have recently been proposed.

For example, a detector installed on the exit side of a rolling mill detects the thickness, width, temperature, etc. of the material to be rolled, and a computer calculates the amount of roll pending using a predetermined crown model formula. Methods for automatically controlling the output to the screws or the load distribution to each rolling mill are also well known.

However, the conventional computer-based method for determining the crown pedestal O has a problem in terms of accuracy or control margin, which is small.

The present invention has been made in order to eliminate the drawbacks observed in the conventional method of controlling offset and crown in continuous rolling of steel sheets as described above, and provides a simple structure for controlling offset and/or crown. The objective is to provide a continuous steel plate rolling facility that allows a rolling mill to perform accurate and continuous Q-rolling. With regard to the steel plate continuous rolling equipment G that is installed,
The amount of change in the inclination angle of the work roll axis with respect to the threading direction is determined by using the detected amounts from the offset detector installed on the exit side of each stand and the profile detector installed on the exit side of the finishing rolling mill as input signals. The present invention is characterized by comprising: an arithmetic control device that performs calculations and outputs a simultaneous bias and crown operation command to a specified work roll; and a hydraulic control device that operates the work roll in accordance with the operation command signal. Located in continuous steel plate rolling equipment.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In FIG. 1, 1 is a finishing rolling mill, and 2 is a front rolling mill.

(In the present invention, the final rolling mill among the tandem continuous rolling equipment for steel sheets is referred to as a finishing mill.

) In actual continuous steel plate rolling equipment, four to six rolling mills are normally installed in tandem before the front rolling mill 2, but for convenience of explanation, only two adjacent stands are shown in Figure 1. Let us illustrate this.

The finishing rolling mill 1 and the front rolling mill 2 have upper work rolls 3, 3', lower work rolls 4.4', upper backup rolls 5, 5', and lower backup rolls 6, respectively.
It consists of 6'.

Reference numeral 30 denotes a well-known profile detector installed on the exit side of the finishing rolling mill 1, and the profile detector 30 scans the steel plate 8 in the width direction using X-rays or γ-rays to measure the thickness. It consists of a scanning thickness gauge 30a and a central fixed thickness gauge 30b that measures the thickness at the center position in the width direction.

7 and 7' are well-known deviation detectors that are installed on the exit side of each stand and optically detect deviation, and as shown in FIG. It is designed to hold lc.

Note that the center line x along the root direction C of the fields of view a and a',
The width l between x' is set in advance to be equal to the rolling width dimension of the steel plate 8. For example, if both ends of the steel plate 8 are offset by Jd, Ad2, the width l between x'
−1−Jd・ is obtained, and the amount of deviation is
1 2 Distinguishing the direction is done by attaching a positive or negative sign to either the left or right side.

Reference numeral 9 denotes an arithmetic and control unit which calculates the amount of deviation from the detection signals detected from the deviation detectors 7 and 7', and also calculates the deviation amount and the signal from the profile detector 30, which will be described later. The amount of work roll operation is calculated using other set values as input signals.

Reference numeral 10 denotes a hydraulic control device which receives a work roll operation command signal from the arithmetic and control device 9 and issues a hydraulic control command to the work rolls of each rolling mill.

Hydraulic cylinders 11 to 14 and 15 to 18 are provided so that the upper and lower work rolls 3 and 4 of the finishing rolling mill 1 can be horizontally moved relative to a stand housing (not shown).

Hydraulic cylinders 11' to 14' and 15' to 18' horizontally move the upper and lower work rolls 3' and 4' of the front rolling mill 2.

The hydraulic cylinders of each stand are connected so that a hydraulic control command signal from the hydraulic control device 10 is input thereto.

Next, the apparatus of the present invention will be explained in more detail with reference to FIG. 3Q.

19 is a stand housing of the finishing rolling mill 1; 20, 2;
0' is a backup roll chock that supports the upper backup roll 5 and lower backup roll 6, respectively; 21 and 21' are wind liners inserted in the stand housing 19; and 22 and 22' are the upper and lower work rolls 3.
, 4 are each upper and lower work roll chock.

23, 23' are position detection ends for detecting the separation distance between the wind liners 21, 21' and the upper and lower work roll chocks 22, 22', and the position detection ends 23, 23't
For this purpose, a well-known magnet scale using magnetism or a potentiometer using electric resistance can be used.

24 is a lowering device, 25 is an upper work roll control servo valve,
27 is a hydraulic pump.

Although FIG. 3 shows only one side of the stand (for example, the work side), the position detection end 23,
23' and upper and lower work roll control servo valves 25, 2
A similar device (not shown) corresponding to 6 is provided.

The apparatus of the present invention having the above-mentioned configuration will be described next, and for the sake of simplicity, the effects of the bias control and the crown control will be described separately.

The detection signal detected by the offset detector is sent to the arithmetic and control unit 9.
The deviation amount is calculated, and as a result of comparison with the predetermined allowable limit deviation amount, if the detected amount is smaller than the deviation value, the corresponding work roll operation amount will be described later. When calculated using the following formula, Q sends a work crawl operation command signal to the hydraulic control device 10.

The hydraulic control device 10 is a hydraulic cylinder 1 of the finishing rolling mill 1.
Hydraulic control commands to 1 to 18 (thread control lines 33a to 33 in Fig. 1)
Fig. 3 shows only the hydraulic control command systems 33a and 33c on the work side (indicated by d).

Now, if the command operation amount of the upper work roll 3 via the hydraulic control command system 33c is larger than the detection amount detected by the position detection end 23, the upper work roll control servo valve 25
operates the hydraulic cylinder 14, and presses the upper work roll chock by an amount corresponding to the horizontal direction Q and O indicated by the arrow Z.

Conversely, if the commanded actuation amount is smaller, the upper work roll control servo valve 25 operates the hydraulic cylinder 13 to press the upper roll chock 22 in the opposite direction to the arrow Z.

Similarly, the actuation amount for the lower work roll 4 is determined by the lower work roll control servo valve 26 and the hydraulic cylinder 17.18.
configured via.

FIGS. 4A, 4B, and 4C show the positional relationship between the upper work roll 3 and the lower work roll 4 relative to the steel plate 8 when performing offset control in the apparatus of the present invention having the above-mentioned structure.

The threading direction C of the steel plate 8 (the axis Y (indicated by an imaginary line) perpendicular to the direction C indicates the position of the axes of the upper and lower work rolls 3 and 4 in the normal case where no offset control is performed, but when the offset control is not performed When carrying out the above-mentioned operation of the hydraulic cylinders, the upper and lower work rolls are moved simultaneously (and in the same direction { Move this.

Figure 4A shows that the direction C' of the steel plate is on the drive side (if it is on the drive side, the axis Y of each upper and lower work roll is
1 in the clockwise direction, and as shown in Fig.
1 is tilted counterclockwise with respect to the axis ytc.

Note that this inclination angle change is performed using the intersection point Q between the axis Y and the center point X in the width direction of the sheet threading line as the center of rotation, so that the amount of operation on the drive side and the work side are always the same. It has become.

Figure 4 shows the side view of Figure 4 A.

Next, in the case of profile control, the profile detector 30 (therefore, the signal of the difference between the average value of the center plate thickness and both end plate thicknesses in the width direction G of the steel plate is input to the arithmetic and control unit 9). , find the deviation from the preset target crown value,
Next, calculate! The leg device 9 calculates the amount of work roll operation according to the deviation value and sends a work roll operation command signal to the hydraulic control device 10.

The hydraulic control device 10 issues hydraulic control commands to the hydraulic cylinders 11 to 18 of the finishing rolling mill 1, and the hydraulic cylinders 11 to 18 control the upper and lower work rolls in the same manner as in the case of the above-mentioned offset control. The pressure is applied in the horizontal direction by an amount corresponding to the amount of actuation (f).

The positional relationship between the upper and lower work rolls when performing crown control is shown in Figure 5A and 5.

By pressing the chock support ends P, P' of the upper and lower rolls 3, 4 with a hydraulic cylinder (not shown), the support ends P, P' are aligned with the width direction center line It moves in the horizontal direction by an amount corresponding to the actuation amount S, , S2 with respect to the axis Y.

At this time, it is controlled so that 81=82 always holds, and the operating direction in the horizontal direction Q is controlled to be opposite.

The axes Y1 and Y2 of the upper and lower work rolls at the chock support ends P and P'ic are separated by a distance of S1+S2=S, and the axes Y1 and Y2 of the upper and lower work rolls intersect on the center line X in the width direction.

That is, in the present invention, the axes of the upper and lower work rolls are configured to intersect at the center point Q in the width direction, and the actuation amount S1,828
By adjusting the corresponding inclination angles α, α2, a steel plate having an arbitrary crown can be obtained (this is what we focused on).

FIG. 6 is a diagram showing that a desired crown can be obtained by changing the distance between the axes of the upper and lower work rolls at the center of the chock (corresponding to St in FIG. 5A); this relationship is based on the diameter of the work roll, The width of the steel plate is determined by the distance between the chocks ('(, G?: equivalent) in Figure 5 A).

Now, in the above explanation, the effects of the offset control and the crown control have been described separately, but the feature of the present invention is that the offset control and the crown control are performed at the same time. The operation of the upper and lower work rolls will be further explained.

Fig. 7 shows the set positions of the upper work roll axis Y1 and the lower work roll axis Y2 when the steel plate 8 is offset in the work side direction C// (and crown correction is also performed at the same time. Crown control is performed. The virtual center line Y' that divides the necessary inclination angle α into two is the inclination angle β for performing anti-clockwise clouding deviation control relative to the axis Y that is orthogonal to the widthwise center line X of the threading line. Set it so that it is tilted only.

Accordingly, in the present invention, setting of the operating amount for simultaneous control of E offset and crown is performed in the following procedure.

Now, let Siuw be the operating amount of the upper work roll on the working side, Siud be the operating amount of the upper work roll on the driving side, and Siud be the operating amount of the lower work roll in any i-th stand among the multiple rolling stands arranged in tandem. Quantity S idw
, when the operating amount of the drive side lower work roll is Sidd, where L: distance between chocks (shown in Figure 4 A or Figure 5 A) αi: inclination angle formed by the axes of the upper and lower work rolls (the (shown in Fig. 5) βi: Inclination angle between a line perpendicular to the sheet threading direction and the work roll axis (shown in Fig. 4 A and C) Now, in the above equation, αi is from the profile detector, and βi is the offset. The detection signal signal obtained from each detector (it is calculated in detail, but the specific formula is as follows.

(1) αi: Deviation between target crown value and measured crown value is {C, where, Kwi: Stand gain vi of i-stand
According to the present invention, the rolling speed in the i-stand can be controlled simultaneously and continuously for a specific i-stand in a steel plate continuous rolling facility. However, without being limited to this embodiment, the same effect can be obtained even if the operating amount of the work roll is distributed at an arbitrary ratio to a stand upstream from the i stand (according to this). Of course.

Further, since the structure of the apparatus according to the present invention is extremely simple and can be controlled continuously, quality, yield, and efficiency are significantly improved, making it an industrially useful invention.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the configuration of the device of the present invention, and FIG. 2 is a schematic perspective view showing the method for detecting the amount of deviation of the device Q of the present invention.
3 is a schematic diagram showing the side surface and operating mechanism of the rolling mill according to the present invention; FIG.
The figure openings are a schematic side view of Fig. 4A, Fig. 5A is a schematic plan view and side view showing the relationship between the work roll and the steel plate in the case of crown control in the present invention, and Fig. 6 is a schematic side view of the crown change amount and the upper and lower work rolls. FIG. 7 is a graph showing the relationship between the axis distances, and is a schematic plan view showing the relationship between the work roll and the steel plate when the offset and crown are controlled simultaneously. 1. : finishing rolling mill, 2: front rolling mill, 3, 3': upper work roll, 4, 4': lower work roll, 5, 5' upper backup roll, 6, 6': lower backup roll,
7, 7': Offset detector, 8: Steel plate, 9: Arithmetic control device, 10: Hydraulic control device, 11~is, 'ii'~18'
: Hydraulic cylinder, 19, two-stand housing, 20,
20': Backup roll chock, 21, 21'
: Wind liner, 22, 22': Work roll chock, 23, 23' 2 Upper and lower work roll control servo valves, 3
0 profile detector, 27: hydraulic pump, X: center line in the width direction of the sheet passing line, Y axis line perpendicular to the two sheet passing line, β
: Inclination angle of the work roll with respect to the axis Y, α: Intersection angle between the upper and lower work roll axes, L: Choke distance.

Claims (1)

[Claims] 1. In a continuous steel plate rolling facility in which rolling stands having work rolls and backup rolls are arranged in tandem, a deviation detector installed on the exit side of each stand and a profile installed on the exit side of the finishing rolling mill are used. an arithmetic and control device that uses each detected amount from the detector as an input signal to calculate an amount of change in the inclination angle of the work roll axis with respect to the sheet passing direction, and outputs a simultaneous biasing and crowning operation command signal to the specified work roll; A continuous steel plate rolling facility comprising: a hydraulic control device that operates work rolls in accordance with the operation command signal.