JPH0321242B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speed control device for a hot run table in, for example, a hot strip mill (continuous hot strip rolling mill) installed in a steel plant or the like.

FIG. 1 is a block diagram showing a conventional speed control device of this type, in which 1 is a finishing rolling mill group of a hot strip mill, 2 is a hot run table divided into four sections from section 2a to section 2d; 3 is a pinch roll; 4 is a coiler that takes the strip 4A rolled to a predetermined thickness; 5 is a group of numerous detection sensors that detect the positions of the leading and trailing ends of the strip 4A passing through; 5a to 5g are the finished strips 4A; Detection sensors 5h to 5k are installed in a plurality of rolling load cells disposed in each finishing rolling mill of the rolling mill group 1, and 5h to 5k correspond to sections 2a to 2 of the hot run table 2, respectively.
A detection sensor 5l is provided on a thermometer arranged corresponding to d, and a detection sensor 5l is arranged corresponding to the coiler 4, and detects based on a current signal of a drive motor (not shown) of the coiler 4. It is. 6 is a tracking circuit for the tip position and tail end position of the strip 4A based on the signals from each detection sensor group 5, 7 is a speed standard setting circuit for the strip 4A, and 8 is a speed correction ratio for the speed standard of the strip 4A. Lead rate setting circuit for
9 is a similar lag rate setting circuit. Note that the lead rate refers to the ratio of the speed of the strip 4A to the speed standard during accelerated rolling, and the lag rate refers to
The ratio of the speed of the strip 4A to the speed standard during deceleration rolling is shown. Reference numerals 10 and 11 designate a lead timing generation circuit and a lag timing generation circuit for generating lead and lag timing based on the tracking signal output from the tracking circuit 6, which open and close the contacts "A" and "B". This is what they are supposed to do. 12 is a multiplier,
13 is a thyristor device for driving an electric motor, 14a~
Reference numeral 14d denotes a plurality of drive motors for driving the hot run table 2 for each section 2a to 2d.

A conventional speed control device of this type is constructed as described above, and the strip 4A rolled to a predetermined thickness by the finishing rolling mill group 1 is transferred to the section 2a.
After passing through the hot run table 2 divided into ~2d, the strip passes through the pinch rolls 3 and is wound onto the coiler 4. The relationship between the speed of the strip 4A until it is wound and the speed of the hot run table 2 is as shown in FIG.

FIG. 2 is a characteristic diagram showing the speed relationship between the speed of the rolled strip 4A (indicated by a dashed line) and the speed of the hot run table 2 (indicated by a solid line). from,
The finishing rolling mill group 1 is accelerated and decelerated so that it reaches a constant speed when the tail end of the strip 4A, which has been rolled to a predetermined thickness at a predetermined speed, passes through the last finishing mill 5g. When the tail end of the strip 4A passes through the pinch roll 3, the speed is decelerated to a constant speed, and when the tail end of the strip 4A reaches the coiler 4, it is configured to stop. At this time, the speed of each section 2a to 2d of the hot run table 2 is made faster than the conveying speed of the strip 4A until the coiler winding starts, and the ratio is set as the lead rate. Further, when the tail end of the strip 4A passes through the last finishing rolling mill 5g, the conveyance speed of the strip 4A is made slower than that of the strip 4A, and the rate is set as a lag rate.

Next, the operation will be explained with reference to FIG. 1 above. That is, the detection signals detected by the large number of detection sensor groups 5 are input to the tracking circuit 6, and the positions of the leading and trailing ends of the strip 4A can be determined. , the lead timing generation circuit 10 starts the coiler 4 from the time when the tip of the strip 4A passes through the last finishing mill 5g.
Contact A is “closed” until the winding starts.
Generates a signal to operate. The lag timing generation circuit 11 also closes the contact B from the time when the tail end of the strip 4A passes through the last finishing rolling mill 5g until it passes through each section 2a to 2d of the hot run table 2. Generates a signal to operate.

On the other hand, by calculating the signal of the speed standard setting circuit 7 for setting the speed of the strip 4a, the signals of the lead rate setting circuit 8 and the lag rate setting circuit 9 using the multiplier 12, the above-mentioned setting "A" is calculated. ” “B”
is added to or subtracted from the signal of the speed reference setting circuit 7 at each timing of the thyristor device 1.
By inputting in 3, the hottran table 2
The drive motors 14a to 14d are rotationally driven. The above explanation is
The operation has been described for the hot run table 2 divided into four sections 2a to 2d, but even if the hot run table 2 is divided into sections 1 to 3, the operation is the same, only the input and output changes. Needless to say.

Since the speed control device in the conventional hot run table is configured as described above, the "lag rate"
It is impossible to change the value corresponding to the strip 4A, and its value becomes a fixed value after the tail end of the strip 4A passes through the last finishing mill 5g, so it depends on the type and thickness of the strip 4A to be rolled. It cannot cope with changes in temperature, temperature, etc., and has disadvantages such as "springing up" of the tail end of the strip 4A or uneven winding of the coiler 4, which adversely affects the shape of the product.

This invention was made with attention paid to this point, and the type, thickness, temperature, etc. of the strip to be rolled,
By making the ``lead rate'' and ``lag rate'' variable in response to changes in the position of the strip and tail end, etc., the speed of the hot run table can be controlled optimally. The present invention aims to provide a speed control device for a hot run table that does not adversely affect the shape of the product, such as "spring-up" of the tip and tail ends or irregular winding of the coiler.

That is, although FIGS. 3 and 4 show one embodiment of the present invention, the same reference numerals as in the above-mentioned conventional system [FIGS. 1 and 2] refer to the same constituent members, and their explanations will be omitted. do.

15 is a lag start point detection circuit that detects the position of the tail end of the strip 4A based on the output signals of the tracking circuit 6 at the tip and tail ends of the strip 4A; 16 is a lag start point setting circuit;
Third lag start point setting circuit 16a, 16b,
16c. 17 is a coincidence detection circuit, and each lag start point setting circuit 16 mentioned above
Primary ~ connected to a, 16b, 16c respectively
The lag start point detection circuit 15 is composed of tertiary coincidence detection circuits 17a, 17b, and 17c.
This is provided to detect the coincidence between the detection signal of the circuit and the setting circuit signals of the primary to tertiary lag start point setting circuits 16a, 16b, and 16c. It is designed to generate an opening/closing timing signal. 18 is a lag rate setting circuit, and the primary to tertiary lag rate setting circuits 1 are connected to the above-mentioned contacts "C", "D", and "E", respectively.
8a, 18b, and 18c, and the speed reference signal of the speed reference setting circuit 7 is modified by opening and closing the contacts "C", "D", and "E". Note that ~ is the lag start point provided in each finishing rolling mill group.

Since the speed control device for the hot run table of the present invention is constructed as described above, each detection sensor group 5 detects the tip and tail ends of the strip 4A.
By inputting the detection signals a to 5l to the tracking circuit 6, the positions of the leading and trailing ends of the strip 4A can be recognized for each strip. Based on the tracking signal from the tracking circuit 6, the lag start point detection circuit 1
5 strips the lag starting point~4A
When the tail end of passes, a value between ``1'' and ``10'' is generated.

On the other hand, lag start point setting circuits 16a, 16
b and 16c are circuits for setting the lag start points of the first to third orders, and are set with the above-mentioned numerical values "1" to "10". Then, set these two values to 1
The next to third match detection circuits 17a, 17b, and 17c compare and when they match, the contact signal is "closed".
make it work. In addition, the first to third order lag rate setting circuit 1
The lag rate set by 8a, 18b, 18c is selected according to the opening and closing of contacts "C", "D" and "E", and is applied by multiplier 12 from speed reference setting circuit 7 of strip 4A. The signal is multiplied by the signal to calculate the speed correction signal, and this signal is subtracted from the speed reference to become the speed reference signal for the four sections 2a to 2d of the hot run table 2.Next, this signal is input to the thyristor device 13, and furthermore, the hot run table 2
The signal is input to the drive motor 14d of the section 2d to drive the hot run table.

Next, FIG. 4 shows the relationship between the speed of the four sections 2d of the hot run table 2 (indicated by a solid line) and the speed of the strip 4A (indicated by a dashed-dotted line) in this invention. However, the lead rate is corrected for the speed of the hot run table 2 from the time it passes through the last finishing rolling mill 5g until the start of winding around the coiler 4, and accelerated rolling is performed from the time of winding around the coiler.
When the tail end of the strip 4A passes the last finishing rolling mill 5g, deceleration is started so that the speed is constant, and when the tail end of the strip 4A reaches the primary lag start point, the 4 of the hot run table 2 In sections 2a to 2d, the speed is corrected for the first-order lag ratio, and when passing through the last finishing rolling mill at the second-order lag start point, the speed is corrected for the second-order lag ratio, and then the third-order lag ratio is corrected. When passing the 2nd section of the lag start point of , the speed is corrected to the 3rd order lag rate, and when passing the 4th section of the hot run table 2, the speed of the next strip 4A is changed to the speed of the next strip 4A. As mentioned above, as the tail end of the strip 4A passes from the finishing mill group 1 to the hot run table 2, the speed of the hot run table 2 is adjusted by the lag rate. The correction is made by In addition, although the above explanation has been about the operation of the four sections 2a to 2d of the hot run table 2, the operation of the four sections 2a to 2d of the hot run table 2 is also
It goes without saying that similar effects can be obtained, only the input and output are different.

As described above, according to the present invention, the "lag rate" is not set to a fixed value as in the past, but is determined based on the type, thickness, temperature, etc. of the strip 4A to be rolled, and the position of the tail end of the strip 4A. Strip 4A can be set to the optimum value corresponding to
This has the excellent effect of significantly improving workability without causing any adverse effects on the shape of the product, such as "springing up" of the tail end or uneven winding of the coiler 4.

In addition, in the above-mentioned embodiment, the first to third
Although the following "lag rate" has been described, the "lag rate" may be set in more detail. Furthermore, in the above embodiment, the primary lag ratio is corrected before the tail end of the strip passes through the last finishing rolling mill. It functions most effectively after passing through the last finishing mill, and the lag ratio may be corrected only after passing through the last finishing mill.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a conventional speed control device for a hot run table, Fig. 2 is a characteristic diagram showing the speed relationship between the rolled strip and the hot run table, and Fig. 3 shows an embodiment of the present invention. The block diagram, FIG. 4, is a characteristic diagram showing the speed relationship between the rolled strip and the hot run table. In the drawing, 1 is the finishing rolling mill group, 2 is the section 2a
A hot run table divided into ~2d, 3 a pinch roll, 4 a coiler, and 5 a detection sensor 5a~
A detection sensor group consisting of 5L, 6 a tracking circuit, 7 a speed reference setting circuit, 8 a read rate setting circuit, 10 a read timing generation circuit, 11 a lag timing generation circuit, 12 a multiplier, 13 a thyristor device, 14a to 14d are electric motors for driving the hot run table, 15 is a lag start point detection circuit, 16 is a lag start point setting circuit, 16
a to 16c are primary to tertiary lag start point setting circuits, 17 is a coincidence detection circuit, 17a to 17c are primary to tertiary coincidence detection circuits, 18 is a lag rate setting circuit, 1
8a to 18c are primary to tertiary lag rate setting circuits, A,
C, D, and E are contact points. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] 1. In a speed control device for a hot run table that transports a strip rolled by a finishing mill and transports the strip to a coiler that winds the strip, it is installed at each point where the hot run table is divided into a plurality of sections, and A plurality of sensors detecting the tail end, a tracking circuit inputting the detection signals of the plurality of sensors and tracking the tail end of the strip, and a point detection device detecting the point of the tail end of the strip using the tracking signal of the tracking circuit. A circuit, a plurality of point setting circuits each having a different point set, is provided corresponding to the plurality of point setting circuits, and outputs when the point detected by the above point detection circuit matches the point of the corresponding point setting circuit. a plurality of coincidence detection circuits, a plurality of lag rate setting circuits each having a different lag rate, selecting a lag rate of any of the plurality of lag rate setting circuits based on the outputs of the plurality of coincidence detection circuits;
A speed control device for a hot run table, comprising means for controlling the speed of the hot run table based on the lag rate.