JPS5813460A - Speed setter for drawing line in casting - Google Patents

Abstract

PURPOSE:To provide a titled device which can generate speed command signals of high reliability by making the 1st and 2nd speed setters selectable respectively arbitrarily and changing the drawing speed gently in accordance with the characteristics of respective function generators. CONSTITUTION:The 1st speed setter 24 is provided to a control board 22 for a casting hearth and the 2nd speed setters 25, 26 are provided on a control board for cutting. The outputs of the setters 24, 25 are selected alternately by the 1st selection switch 27, and the output of an amplifier 30 and the output of the setter 26 are selected alternately by the 2nd selection switch 28. The 1st function generator 29 has the rising characteristics of gentle inclination, and the 2nd function generator 31 has the characteristics of sharp inclination. In accordance with the operation of the above-mentioned two switches 27, 28, the setters 24, 25, 26 select the speed command signals C1, C2, C3 for pinch rolls on the uppermost stream side and others properly and output the commands for changing their speeds.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to continuous casting equipment installed in a steelworks, and more specifically, the invention relates to continuous casting equipment installed in a steelworks. This relates to a setting device.

Continuous casting equipment is equipment used in, for example, steel works to continuously cast molten steel supplied from a converter or the like, and its outline is shown in FIG. In FIG. 1, an opening 1 is provided at the bottom of the supply from a converter or the like through which molten steel flows out. 2 is called molten dish which is supplied from 1 dollar to 1 dollar. Further, 4 is a casting drawing line for drawing out the molten steel, that is, the slab cast by the mold 3, in 1 m order, and 5a, 5b,
6as 6bs? '17b is a pair of first to third pinch rolls for pulling out the slab along the casting drawing line. The first pinch roll pair 5''s5b of these pinch roll pairs is driven by the first drive motor 8, and the second pinch roll pair 6-.6b is driven by the first drive motor 8.
is configured to be driven by a second drive motor 9, and the third Vinci roll pair 7a, 7b is configured to be driven by a third drive motor 10. These vaginal moaning motors 8
．． 9.1011'.

, Speed control device 11.1
2.13, each is configured to be driven with its rotational speed controlled, and these speed control devices 11.1
2.13 is supplied with speed command signals C8, a, , O, for determining the respective rotational speeds of the drive motors 8.9.10, and is also supplied with a 4-dynamic power source via the terminal 14. . Further, 15 is a cutting machine for cutting the drawn slab into a predetermined length.

The casting operation performed in such continuous casting equipment is as follows. First, at the start of casting, as shown in Figure 2, a dummy bar (indicated by a mesh) shown at 16 is inserted into the casting drawing line.
The lower part of the pipe is closed, and in this state, injection of molten steel is started. The injected molten steel is cooled by a mold 3 connected to a dummy bar 16 and a subsequent secondary cooling zone (a cooling device (not shown) provided along a casting drawing line 4), and is turned into a slab. Pinch roll vs. 5a, 5b~?'%
7b in the direction of arrow 17. So'L
In fact, when the tip of the slab passes through the pair of pinch rolls 7&, 7b, the dummy bar 16 is separated from the slab, and thereafter, for example, the drawing of the slab continues only by the pair of pinch rolls T, 7b. Further, the thus cast slab is cut into predetermined lengths by a cutting machine 15 and sent to the next process.

By the way, in the continuous casting equipment as described above, the casting operation operator 19 on the casting bed 18 controls the control of the drawing speed of slabs in the casting drawing line at the beginning of casting. In addition, when pulling out the remaining cast pieces remaining at the end of casting or in the casting drawing line 4, the cutting operation operator 2 in the cutting operator room 20
It is desirable that 1 person have this. Therefore, in such continuous casting equipment, a speed setting device 5 for setting the drawing speed of slabs is installed on the casting bed operating panel 22 in the casting bed 18 and the cutting operating panel 23 in the cutting operator room 20, respectively. It is necessary to provide these speed setting devices, and it is necessary to be able to switch each of these speed setting devices depending on the casting operation status.Furthermore, at the time of switching, the drawing speed of the slab changes rapidly. It is essential that the drawing speed be changed slowly to avoid breakout of the slab (the solidified layer on the surface of the slab breaks and the molten steel inside flows out).

In order to satisfy the above conditions, conventional speed setting devices:
With the configuration described below, speed command signals a, , O,
, O, were generated respectively. That is, in response to a speed setting signal selectively supplied from a speed setting device provided on the casting bed operation panel 22 and the cutting operation panel 23 in correspondence with each pair of pinch rolls, the rotational speed is constant. A following servo motor is provided, and a signal corresponding to the resistance value indicated by a potentiometer linked to the motor shaft of the servo motor is output as a speed command signal. According to such a configuration, since the rotational speed of the servo motor is constant, the rotational speed of each pair of pinch rolls can be gradually changed. However, in such a speed setting device, there is no need to change the speed setting location (the casting bed 18 or the cutting cab 20).
When separating into the cutting operation cab 20, it is necessary to wait for the completion of the casting operation, and, contrary to the above-mentioned case, when combining and joining, it is necessary to wait for the completion of the cutting operation. As described above, conventional speed setting devices have the problem of long waiting times, and because they use servo motors and potentiometers, the reliability of the devices is low and maintenance work is troublesome. There was a problem.

In view of the above-mentioned circumstances, this invention allows the setting location of the slab drawing speed to be changed arbitrarily according to the operational status of the casting without stopping the slab pulling operation, and is highly reliable. It is an object of the present invention to provide a speed setting device for a casting and drawing line capable of generating a speed command signal, and by providing first and second switching means, the speed can be set at a predetermined location, respectively. The setter can be switched arbitrarily, and the pull-out speed corresponding to the difference in the set pull-out speed between the speed setters at the time when these switches are made is set at each stage of the first and second function generators. Above) It is assumed that the characteristics change gradually.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 is a block diagram showing the configuration of an embodiment of the present invention. In this figure, 24, 25, and 26 are speed setting devices for setting the drawing speed of the slab, respectively), the speed setting device 2 is installed on the casting bed operation panel 22, and the speed setting device 2 is installed on the casting bed operation panel 22.
5.26 is provided on the cutting operation panel 23. These speed setters 24 to 26 are configured to each output an analog signal corresponding to the set speed.

Both 27 and 28 are changeover switches (11th and 2nd changeover means), and the changeover switch 27 has a 1:1 degree and a changeover switch 2 in order to selectively select each output of the speed setter 24. .8 are provided to selectively select the output of the amplifier 3o or the output of the speed setter 26, which will be described later. Reference numeral 29 denotes a first function generator whose step response has a rising characteristic (first ramp function characteristic) with a predetermined slope. Reference numeral 30 denotes an amplifier provided as necessary, which amplifies the output of the function generator 29 and uses the output as the speed command signal 0. It is supplied to the speed control device 11 described above as well as to the changeover switch 28. 31 is a function generator (second function generator) having the same configuration as the function generator 29, and B is its startup characteristic (second ramp function characteristic, similar to that of the function generator 29). Further, reference numeral 32 denotes an amplifier provided as necessary, which amplifies the output of the function generator 31, and uses the output as speed command signals C, , O, to form the speed control device described above. 12 and 13 respectively.

Next, the operation of this embodiment having the above configuration will be explained in connection with an actual casting operation.

(1) First, at the start of casting, the casting drawing line 4 is loaded with a dummy bar 16 closing the lower part of the mold 3, as shown in FIG.

In this case, the changeover switches 27 and 28 are each set to the state shown by solid lines in FIG. In this state,
Since only the speed setting device 24 of the speed setting devices 24 to 26 is effective, the casting operation operator 19 has the initiative in controlling the drawing speed. Here, when the casting operation operator 19 starts casting and sets a desired drawing speed using the speed setting device 24, the speed command signal C3 is transmitted to the function generator 2.
9 to a value corresponding to the set drawing speed. Further, at this time, the speed command signals 0@, 0@ are because the ramp function characteristic of the function generator 31 is steeper. and % change in approximately the same way. In this way, vintilol pairs 5a, 5b
~"The rotational speeds of 1a and 7b increase at the same speed until they reach the set drawing speed. Thereafter, the casting operation operator 19 operates the speed setting device 24 as necessary.
The drawing speed can be changed arbitrarily and with gradual speed changes that follow the ramp function characteristics of the function generator 29.

■ Next, as the casting work progresses, it stabilizes, and as shown in Figure 5, the tip of the slab (the shaded area)
When the position corresponding to is reached, the changeover switch 27 is switched to the state shown by the broken line (the changeover switch 28 is left unchanged). In this case, even if there is a difference between the drawing speed set in the speed setting device 24 and the drawing speed set in the speed setting device 25 at the time the changeover switch 27 is switched, the difference will be corrected. The speed is changed slowly according to the ramp function characteristics of the function generator 29, etc.

In this case, since only the speed setting device 25 is effective, the cutting operation operator 21 will have the initiative in controlling the drawing speed from now on. It is possible to change the drawing speed.

■ Next, as shown in Fig. M6, the casting is completed and the slab (
When the rear end of the remaining slab passes through the first pair of pinch rolls 5'%5b, the changeover switch 281 is switched to the state shown by the broken line in FIG. In this case, even if there is a difference between the drawing speed set on the speed setting device 25 and the drawing speed set on the speed setting device 20,
Since the speed corresponding to the difference is changed relatively slowly according to the ramp function characteristics of the function generator (n) 31, no problem occurs in the slab cutting operation. Thereafter, the drawing speed of the remaining slab can be changed by the speed setting device 26, that is, by the cutting operation operator 21 taking the initiative.

In this case, the drawing speed is controlled only by the speed setting device 24 (
That is, even if the changeover switch 27 is in the state shown by the solid line i), by switching the changeover switch 28 to the state shown by the broken line shown in FIG. The authority can be transferred to the cutting operator 21 in exactly the same way.

■Next, when the state described in (■) is reached, the rotation speed of the first pinch roll pair 5as5b can be controlled independently, so this state can be used for dummy par 1a revision - large work. Can be done. In this case, the changeover switch 28 can be left as it is, or the speed at which the remaining slab is pulled out can be controlled by the speed setting device 26, and the changeover switch 27 can be set to the state shown by the solid line in FIG. Roll vs. 5&
, 5b are controlled by a speed setter 24. In this way, as shown in FIG. 7, the cutting operation operator 21 takes the initiative in controlling the drawing speed of the remaining slab, and the casting operation operator jiL 19 takes the initiative in inserting the dummy/<-16. It becomes possible to do what you have the right to do.

(2) Next, as shown in FIG. 8, when the state shown in (2) progresses further and the dummy par 16 is completely loaded, the next casting can be started. In this case, if the changeover switch 28 is switched to the state shown by the solid line in FIG. 2 before the tip of the dummy par 16 reaches the position of the second pinch roll pair 6at6b, the pinch roll pairs 6', 6b% 7
The rotational speed of the as 7b is made equal to the rotational speed of the first pinch roll pair 5a, 5b according to the ramp function characteristic of the function generator 31. Therefore, from now on, the control of the withdrawal speed of the remaining cast slab and the next cast slab will be performed by the aging operation operator 19.
can take the initiative.

(13) As described above, according to this embodiment, the drawing speed of the slab can be set by setting the speed setting device 24 of the casting bed operation panel 22 or the speed setting device 25 of the cutting operation panel 23 depending on the casting operation. 26, and in this case, there is no need to stop the drawing operation when switching the speed setters 24 to 20. Further, the casting operation can be performed continuously without stopping the casting drawing line, such as start of casting → drawing of slab → cutting of slab → insertion of dummy bar 16 → start of next casting.

Next, specific examples of the above-mentioned subtraction example are shown in FIGS. 9 and 10.

FIG. 9 shows this first specific example, and in this figure, parts corresponding to those in FIG. 3 are given the same reference numerals and their explanations will be omitted. In FIG. 9, the analog servo amplifier 29a has a response characteristic that is a combination of three ramp function characteristics whose slope becomes gradually gentler as the correlation increases, and this response characteristic is the same as that of the switches 33 and 34.
．． a set mode signal applied via 35 and 36, respectively;
Stop (14) Changes according to the stop mode signal, casting mode signal, and drawing mode signal. Further, the delay element 29b is provided to round off the connection portion of the ramp function characteristic having different rise, fall and slope of the response characteristic of the analog servo amplifier 20a. In this first specific example, the casting drawing speed set by the speed setting device 24 is sent to a control computer (not shown) via the signal converter 37, and is returned from the computer. The speed correction signal is taken in via the signal converter 38, and the resulting speed command signal C1 is sent as a confirmation signal to the computer via the signal converter 39, thereby achieving digital control by the computer. It is configured so that it can be carried out.

Next, FIG. 10 shows a second specific example of the above-mentioned embodiment. In this figure, parts corresponding to those in FIGS. 3 and 9 are designated by the same □2 symbols. . In addition, in this second specific example, the pinch roll pair 5a%5b~7
Inverters 40 and 41 are used to reversely rotate aN7b.
, forward/reverse switching (15) switches 42ax, 42bs +aa, 4-3b, etc. are connected to V&.

As explained above, according to the speed setting device for a casting drawing line according to the present invention, the first switching means selectively selects each output of the first and second speed setting devices, and the switching means A first function generator that imparts a first rise characteristic to the output; a first speed command signal based on the output of the first function generator; and an output of the third speed setter. a second switching means for selecting, and a second function generator for imparting a second rising characteristic having a steeper slope than the first rising D% characteristic to the output of the second switching means. a predetermined number of consecutive bins on the most upstream side of the a-making drawing line according to the first speed command signal;
A second speed command signal for controlling the rotational speed of the Tyrol pair and based on the output of the second function generator'''11 Sea MgoWyy
Since the rotation speed is controlled, the initiative in setting the slab withdrawal speed can be switched arbitrarily to the pouring bed side or the cutting machine side, depending on the casting operation status. The possible options are also set at this switching point (16
) Even if there is a difference in the drawing speed, the drawing speed is changed gradually, so there is no strain on the drawing operation of the zero piece, and therefore there is no need to stop the drawing operation. Furthermore, when the current casting is completed, the remaining cast pieces are pulled out, a dummy bar is inserted in preparation for the next casting, and casting can be started immediately, so casting can be repeated without any waiting time. You can do it again.

Further, since the speed command signal is generated using a function generator, the reliability of the control of the drawing speed can be extremely high, and the apparatus can be made maintenance-free.

[Brief explanation of the drawing]

Figure 1 is a diagram showing an overview of the continuous casting equipment, Figure 2 is a diagram to explain the casting operation in the same continuous casting equipment, and Figure 9 is a diagram showing the first specific example of the same embodiment. The figure shown in FIG. 10 is a diagram showing a second specific example of the same embodiment. (17) 4...Casting drawing line, 5a%5b...
・First pinch roll pair, aas6b...second
Pinch roll pair, 711%'7b...Third pinch roll pair, Minato...First speed setter, 2
5... Second speed setting device, 26... Third speed setting device, 27... First switching means (selector switch), 28... ...Second switching means (selector switch), 29...First function generator, 31
...Second function generator. Applicant: Shindo Electric Co., Ltd. (18) MAI = 320-

Claims (1)

[Claims] Speed setting of a casting drawing line, which sets the drawing speed of slabs in the casting drawing line by setting the rotational speed of each of a plurality of pinch roll pairs provided along the casting drawing line in the continuous casting equipment. The apparatus includes a first switching means for selectively selecting the output of the first speed setting device and the output of the second speed setting device, and a step using the output of the first switching means as an input. Selecting a first function generator whose response has a rise characteristic with a predetermined slope, a first speed command signal based on the output of this first function generator, and an output of a third speed setter. a second switching means for selecting the first function generator; and a second switching means which receives the output of the second switching means and whose step response has a rise characteristic having a steeper slope than the rise characteristic of the first function generator. 2 function generators, and a predetermined number of continuous pinch roll pairs on the most upstream side of the casting drawing line among the plurality of pinch roll pairs in accordance with the first speed command signal. The rotational speed is controlled, and the rotational speed of the remaining pinch roll pair among the plurality of pinch roll pairs is controlled in accordance with a second speed command signal based on the output of the second function generator. A speed setting device for casting and drawing lines featuring: