JPS62124058A - Rolling reduction controlling apparatus for continus casting billet - Google Patents

Abstract

PURPOSE:To control accurately a rolling reduction of a casting billet supplied continu ously by arranging a position detector which detects the position of an ascended and descended metal mold, outputting a command signal from a valve opening com mand unit to a controlling valve by the signal from the position detector and control ling a hydraulic volume to a rolling reduction cylinder. CONSTITUTION:A descending distance of the metal mold body block 14 for rolling reduction, which is descended by descent of a piston rod 7a, is detected by the piston detector 36 and is transmitted to a ground signal generating unit 41 and a displacement meter reset unit 42. When a ground recognizing signal is transmitted from a ground recognizing unit 40 to the displacement meter reset unit 42, the signal of descending distance for the metal mold body block 14 is reset to zero, and after that the signal transmitted from the position detector 36 is actual rolling reduction by the block 14. Further, the total volume for the fluid to be used for reduction is directed from a feedback calculation command unit 45 to a valve opening command unit 46, to adjust opening of the controlling valve 33. Thus, the reduction valve by the metal mold body block 14 for rolling reduction is accurately controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a continuous cast slab reduction control device that can accurately control the amount of reduction of a cast slab from a mold.

[Prior Art] In continuous casting equipment, when a slab solidifies, porosity (small holes) tends to occur near the center of the wall thickness. Since this porosity causes deterioration of the strength and quality of the slab, it is necessary to reduce the slab with some kind of rolling device to compress the porosity.

Also, during solidification, solidification shrinkage occurs inside the thick wall, and if left untreated, gaps will form inside, and molten metal will flow into these gaps from the unsolidified layer, causing segregation due to so-called non-uniformity of components. There is. In order to prevent segregation, a device is required that continuously reduces the slab by an amount corresponding to solidification shrinkage.

For these reasons, there is a need for a device for continuously rolling down the slab in the vicinity of the solidification point, and as a rolling device, the devices shown in FIGS. 4 and 5, for example, have been proposed.

In Fig. 4, 1 is a mold for continuous casting, 2 is a continuous slab handled from the mold 1 (hereinafter simply referred to as a slab), 2-
1 is the solidified layer of slab 2, ? -2 is the unsolidified layer, ? -3 is a porosity (small hole), 3 is an upper pinch roll group with multiple rolls, 4 is a lower pinch roll group with multiple rolls, and the downstream side of the upper and lower pinch roll groups 3.4 is a continuous casting A one-side lowering device 5 is provided.

To explain the continuous slab rolling down device 5, a housing 6 is disposed so as to straddle the slab 2, and the housing 6 includes a vertically oriented fluid pressure cylinder 7 with a piston rod 7a facing downward, and a vertically oriented piston rod 7a. Four sets of fluid pressure cylinders 8 with rods 8a facing upward are arranged as reduction cylinders, and wheels 9 and 10 whose axes extend in the width direction of the slab 2 are rotatably mounted at the lower and upper ends of the piston rods 7a and 8a. It is pivoted to.

Two sets of fluid pressure cylinders 11 parallel to the fluid pressure cylinder 7 are arranged at the front and rear center upper part of the housing 1, and the upper ends of the piston rods 11a of the two sets of fluid pressure cylinders 11 are arranged parallel to the advancing direction of the slab 2. A vertical rod 13 is pivotally attached to a substantially central portion in the longitudinal direction of the lever 12, and a reduction mold main body block 14 is pivotally supported at the lower end of the rod 13.

A guide rail 15 on which a wheel 9 can roll is fixed to the upper surface of the reduction mold body block 14, and the rod 13 is moved by pressing the piston rod 11a of the hydraulic cylinder 11 upward with pressure oil. The rolling die main block 14 is lifted upward through the guide rail 15, and the guide rail 15 is constantly
It is designed so that it can be brought into contact with the

A guide rail 17 on which the wheels 1o can be moved is fixed to the lower surface of the rolling die body block 16 disposed below the rolling die body block 14. It is mounted on the wheel 10 via.

A liner 18.19 for rolling the slab 2 is removably attached to the lower or upper surface of the rolling mold body block 14.16, and the slab 2 is placed on the upstream side of the housing 6 in the direction of movement of the slab 2. A beam 20.21 extending in the width direction is fixed, and a bracket 22.21 is fixed to the beam 20.21.
23, the rear ends of hydraulic cylinders (reciprocating cylinders 24 and 25) extending in the longitudinal direction of the slab 2 are pivotally supported, and piston rods 24a, 25 of the hydraulic cylinders 24, 25
The tip a is connected to a bracket 26.27 fixed to the rear surface of the reduction mold main body block 14.16, and is attached to the housing 6.
At the upper and lower portions of both widthwise sides of the roll-down mold body block 14.16, when the roll-down mold body block 14.16 is reciprocated in the longitudinal direction of the slab 2 by the fluid pressure cylinders 24.25.
Guide blocks 28, 29 for guiding the guide 16 are fixed.

Reference numeral 30.31 in Fig. 5 is a position detector, and it is also possible to interlock drive the rolling down structure of the slab 2 with the reciprocating device in the patent application filed in 1986-
It is disclosed in the specification of No. 81540 and the specification of Japanese Patent Application No. 77226/1983.

In the slab continuous reduction forming apparatus 5, the rolling die main body block 14.16 is moved up and down relative to the slab by the fluid pressure cylinder 7.8, and the fluid pressure cylinder 24
．． 25 performs reciprocating motion in the longitudinal direction of the slab 2.

Therefore, by combining the movements of the fluid pressure cylinders 7.8 and 24.25, the rolling mold body block 14.16 is given spatial trajectories A and A' as shown in FIG. The slab 2, which is continuously moved to, is subjected to rolling reduction. In FIG. 6, P and P' are the rolling die main block 14.
S18' is the section where the rolling die body block 14.16 moves up and down from the slab 2 and moves away from the slab 2, and Q and Q' are the rolling die body block 14.1.
6 returns to the starting position, and R and R' are intervals in which the rolling die main body block 14.16 descends or rises relative to the slab 2, comes into contact with the slab 2, and performs rolling. Due to the reduction, for example, the porosity 2-3 gradually becomes smaller as shown in FIG.

[Problem 1-i to be solved by the invention is that when rolling a slab to prevent porosity or segregation of the slab, the amount of rolling needs to be done accurately to a predetermined value. However, since the rolling down device itself is elastically deformed and the thickness of the slab on the entrance side of the device is constant and fluctuates, it is difficult to set the rolling amount to the correct value. In particular, when the rolling die body block 14.18 is reciprocated in the longitudinal direction of the slab 2 by the hydraulic cylinder 24.25 as described above, the rolling die body blocks 14, 16 move back and forth in the longitudinal direction of the slab 2. Since the landing point in the thickness direction of the slab always changes each time due to dimensional errors in the thickness direction of the slab, the amount of reduction cannot be accurately determined. Further, since the reduction mold body blocks 14 and 16 apply 8 vJ in the longitudinal direction of the slab 2 by the length of the body blocks 14 and 16 together with the slab 2, the amount of reduction of the slab 2 is difficult to reach a correct value.

In view of the above-mentioned circumstances, the present invention has been made with the object of accurately controlling the reduction amount of slabs that have been cast in continuous casting equipment and continuously fed. .

[Means for Solving the Problems] The first aspect of the present invention is to intermittently press a mold against a slab moving in the longitudinal direction by a reduction cylinder, and to move the mold to the length of the slab by a feed cylinder. In a continuous slab rolling device that rolls down slabs while reciprocating in the hand direction,
A position detector that detects when the mold is raised or lowered, and a valve opening command device that outputs a command signal to a valve that controls the amount of pressurized liquid sent to the reduction cylinder based on the signal from the position detector. In addition to the first invention, the second invention includes a landing recognition device for detecting that the mold has landed on the slab, and when the landing recognition device recognizes that the mold has landed on the slab. A device for outputting a set reduction amount of the slab set by a reduction setting device, and a signal output from the device can be sent to the valve opening command device. In addition to the invention of 2, a device is provided for correcting the set reduction amount of the slab set by the reduction amount setting device based on the pressing force of the slab due to reduction, and a signal output from the device is sent to the valve opening command device. It is now available to send.

[Function] In the first invention, the position detector detects the amount of elevation of the mold, the detected value is sent to the valve opening command device, and the valve opening command device sends a command signal to the control valve. The control valve is opened to an opening degree corresponding to the command signal, and the amount of pressurized fluid supplied to the reduction cylinder through the control valve is controlled to control the amount of reduction by the mold. When it is recognized that the mold has landed on the slab, the set reduction amount set by the reduction amount setting device is sent to the valve opening command device, and the reduction amount by the mold is controlled as in the first invention. In invention No. 3, the elastic displacement of the device itself and the mold due to the slab pressing force is determined, the set reduction amount is corrected based on the displacement, the corrected set reduction amount is sent to the valve opening command signal, and the elastic displacement of the device itself and the mold is determined by the slab pressing force. The amount of reduction is controlled.

[Example] Hereinafter, an example of the present invention will be described with reference to the accompanying drawings.

Fig. 1 shows an embodiment of the present invention, and the continuous slab reduction device itself has the same configuration as in Figs. A control device is provided.

In FIG. 1, 32 is a liquid supply pipe equipped with a control valve 33 such as a servo valve, 34 is a pressure detector provided in the liquid supply pipe 32 to detect the pressure of the fluid supplied to the fluid pressure cylinder 7, 35
36 is a non-contact type position detector using an eddy current method, etc., and 37 is fixed to the outside of the guide block 28. This is a metal fitting to be detected when the position detector 36 detects the vertical displacement and up/down amount of the rolling die main body block 16.

The pressure of the fluid pressure cylinder 7 detected by the pressure detector 34 can be applied to the landing signal generation device 38 and the calculation device 39. The landing signal generator 38 has a preset reference level pressure P. is compared with the pressure P□ detected by the pressure detector 34, and if the pressure PR is larger than the reference level pressure PO, a signal is given to the landing point recognition device 40 to increase the pressure 1q. The elastic displacement amount yR' of the rolling die main body block 14 can be determined from PR and the elastic coefficient KR of the rolling die main body block 14.

The position detector 36 can give signals to the landing signal generator 41 and the displacement meter reset device 42,
From the landing signal generator 41, the rolling die main body block 1
4 has landed on the slab, a landing signal can be given to the landing point recognition device 40. Further, the longitudinal displacement X of the rolling die main body block 14 detected by the position detectors 30 and 31 shown in FIG. 4 can be given to the landing signal generator 43.
3, when it is determined that the rolling die main body block 14 has landed on the slab 2, a landing point recognition device 4 sends a landing signal.
It can be given to 0.

The signal of the reduction amount VR detected by the position detector 36 after the reduction mold body block 14 lands on the slab 2 is once reset to zero, and then sent to the calograph calculator 44 via the displacement meter reset device 42. The adder 44 is configured to obtain the deviation AyR of the roll reduction amount from the roll reduction amount yR and the roll reduction set amount yRo set by the roll reduction amount setter 47.

The deviation Ayn between the elastic displacement ff1yR' of the rolling die main body block 14 found by the three calculation devices and the rolling amount found by the adder 39 is determined by the feedback amount calculation command device 45.
The reduction feedback amount yR'' can be added to the valve opening command device 46.

In the valve opening command device 46, pressure reduction feedback @yR”
A valve opening command can be given to the control valve 33 while comparing and calculating the amount of movement of the piston rod 7a of the fluid pressure cylinder 7 detected by the position detector 35.

Note that the gain of the signal fed back to the valve opening degree command device 46 is determined by the feedback amount calculation command device 46, for example.
It is only necessary to adjust the gain C of .

Although the control device shown in FIG. 1 is shown as being provided only on the left side of the left and right fluid pressure cylinders 7, it may also be provided on the right side fluid pressure cylinder 7, and may also be provided on the lower side shown in FIG. It is also provided for the fluid pressure cylinder 8.

During operation, pressure fluid is supplied to the fluid pressure cylinder 7, and the piston rod 7a moves up and down, thereby raising and lowering the reduction mold body block 14. By reciprocating in the direction, the rolling die body block 14 draws a spatial locus A shown in FIG. 6, and similarly the rolling die body block 16
The slab 2 is rolled down while drawing a spatial locus A' shown in FIG.

The control during the reduction molding of the slab 2 will be explained with reference to the reduction mold body block 14. When the piston rod 7a descends, the hydraulic pressure in the chamber of the fluid pressure cylinder 7 is detected by the pressure detector 34, The detected pressure PR is sent to the landing signal generator 38, and if the pressure PR is larger than the reference level pressure PO set in advance in the landing signal generator 38, a landing signal is sent from the landing signal generator 38. The information is sent to the location recognition device 40. Further, the pressure PR detected by the pressure detector 34 is sent to three calculation devices, and is sent to the feedback amount calculation command device @45 as a corrected additional reduction amount for correcting the elastic displacement of the mold body block 14.

On the other hand, the amount of descent of the reduction die main body block 14 due to the descent of the piston rod 7a is detected by the position detector 36, and is sent to the landing signal generator 41 and the displacement meter reset device @42. Accordingly, the landing signal generator 41 uses the signal from the displacement meter 36 to control the rolling die main body block 1.
4 has landed on the slab 2 or not is determined as follows.

That is, when the rolling die main body block 14 has not landed on the slab 2, as shown in FIG. 2, the amount of descent thereof increases in proportion to time according to a straight line A. However,
When the rolling die main body block 14 lands on the slab 2, the main body block 14 receives a landing impact from the slab 2, and cannot descend in a straight line. The amount of descent is significantly reduced. However, as time passes, the pressure of the fluid supplied to the fluid pressure cylinder 7 increases, and the rolling die main body block 14 thereafter descends along the straight line C. Therefore, at a certain time, the predicted descending amount of the rolling die main body block 14 when the rolling die main body block 14 has not landed on the slab 2 is different from the actual descending amount of the rolling die main body block 14. The difference Ayo is calculated, and the difference AJ is a predetermined value Ay.

If it is larger than , it is determined that the rolling die main body block 14 has landed on the slab 2, and a landing signal is sent from the landing signal generator 41 to the landing point recognition device 40.

Further, the amount of movement X of the rolling mold body block 14 in the longitudinal direction of the slab 2 due to the reciprocating movement of the piston rod 24a of the fluid pressure cylinder 24 is detected by the position detector 30.31.
The signal is sent to the landing signal generator 43. The landing signal generator 43 uses the signals from the position detectors 30 and 31 to
A determination as to whether or not the rolling die main body block 14 has landed on the slab 2 is made as follows. That is, when the rolling die main body block 14 does not land on the slab 2, as shown in FIG. , slab? Due to the speed difference between the rolling die body block 14 and the rolling die body block 14, the rolling die body block 14 receives a landing impact, and a certain amount of fluctuation X occurs. occurs. Therefore, if this amount of variation xC is larger than the predetermined value XB, the rolling die main body block 14
is determined to have landed on the slab 2, and a landing signal is sent from the landing signal generating device 43 to the landing point recognition device 40.

The landing point recognition device 40 includes a landing signal generating device 38.41.
For example, if a landing signal is sent from any two of the landing signal generating devices 38 and 41.43, it means that the rolling die main block 14 has landed on the slab 2 Then, a landing point recognition signal is applied from the landing point recognition device 40 to the displacement meter reset device 42. The reason why the landing point recognition signal is outputted from the landing point recognition device 40 when landing signals are sent from two of the landing signal generators 3B and 41.43 is that the rolling die main block 14 This is because detection of the landing point on the slab 2 is generally unstable and difficult to detect. Detecting landing at two locations in this way increases reliability.

Of course, the landing point may be recognized when landing signals are sent from all the devices 38, 41, 43.

When the landing point recognition signal is applied from the landing point recognition device 40 to the displacement meter reset device @42, a signal indicating the amount of descent of the rolling die main block 14 sent from the position detector 36 to the displacement meter reset device 42 is sent from the position detector 36 to the displacement meter reset device 42. is reset to zero, so
Thereafter, the signal sent from the position detector 36 becomes the actual reduction amount after the reduction mold body block 14 lands on the slab 2.

When the displacement meter reset device 42 is reset, the position detector 36 sends a rolling reduction signal to the adder 44, and the adder 44 adjusts the rolling setting 4 set by the rolling reduction amount setter 47.
The deviation AyR between VR□ and the reduction amount yR is calculated, and the deviation A
yR is added to the feedback amount calculation command device 45. Further, the calculation device 3 is connected to the feedback amount calculation command device 45.
Since the signal of the elastic displacement amount VB' calculated in step 9 is also sent, the feedback amount calculation command device 45 calculates the deviation A.
yR and the elastic displacement amount yR' are added, and from the command device 45, the reduction feedback amount ')/R'' is added to the valve opening command device 46 as the total amount to be reduced. The opening degree of the control valve 33 is adjusted by the command signal. Therefore, the amount of pressure fluid supplied from the control valve 33 to the fluid pressure cylinder 7 is controlled, the piston rod 7a is lowered by a predetermined amount, and the mold is rolled down. The amount of pressure reduction by the main body block 14 is controlled to an accurate value.The amount of descent of the piston rod 7a is detected by the position detector 35, and is fed back to the valve opening command device 46, and when the piston rod 7a is lowered by a predetermined amount, the valve opening is adjusted. No command signal is output from the command device 46, and the control valve 33 is closed.

Note that the present invention is not limited to the above-described embodiments, and it is possible to use a load detector such as a load cell in place of the pressure detector, and various other changes may be made without departing from the gist of the present invention. Of course, it is also possible to add

[Effects of the Invention] According to the continuous slab reduction control device of the present invention, even if the entire device such as the housing and the mold are deformed, and the thickness of the slab changes on the entry side, the reduction of the mold relative to the slab can be controlled. An excellent effect can be achieved in that the amount can be accurately controlled.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the continuous slab reduction control device of the present invention;
The figure is a graph showing the relationship between the amount of descent of the rolling die main body block and time in the device shown in FIG. FIG. 4 is an explanatory diagram of an example of a continuous slab reduction device proposed so far to which the continuous slab reduction control device of the present invention can be applied, and FIG. 5 is a graph showing the relationship between the following: A perspective view of the apparatus, FIG. 6 is an explanatory diagram of the spatial locus of the rolling die main body block of the apparatus of FIG. 4. In the figure, 5 is a continuous slab rolling device, 6 is a housing, 7, 8.
24.25 are fluid pressure cylinders, 7a, 8a, 24a
, 25a is a piston rod, 14.16 is a reduction mold body block, 30, 31, 35.36 is a position detector, 3
2 is a liquid supply pipe, 33 is a control valve, 34 is a pressure detector, 38.
41. 43 is a landing signal generator, 39 is a calculation device, 40
42 is a displacement meter reset device, 44 is an adder, 45 is a feedback amount calculation command device, 46 is a valve opening command device, and 47 is a reduction amount setting device. Figure 1

Claims (1)

[Claims] 1) A reduction cylinder intermittently presses the mold against the slab moving in the longitudinal direction, and a feed cylinder moves the mold back and forth in the longitudinal direction while reducing the slab. A continuous cast slab rolling down device includes a position detector that detects the amount of elevation of the mold, and a valve that outputs a command signal to a valve that controls the amount of pressurized liquid sent to the rolling cylinder based on the signal from the position detector. A continuous slab reduction control device characterized by being equipped with an opening command device. 2) A continuous slab reduction device in which a reduction cylinder intermittently presses a mold against a slab moving in the longitudinal direction, and a feed cylinder reciprocates the mold in the longitudinal direction of the slab while rolling down the slab. , a position detector detects the amount of elevation of the mold, a landing recognition device detects that the mold has landed on the slab, and when the landing recognition device recognizes that the mold has landed on the slab, it sets the reduction amount. A device for outputting the set amount of slab reduction set by the device, and a valve opening command device for outputting a command signal to a valve that controls the amount of pressure fluid sent to the reduction cylinder based on the signal from the device. A continuous slab reduction control device characterized by the following. 3) A continuous slab reduction device that uses a reduction cylinder to intermittently press the mold against the slab moving in the longitudinal direction, and also uses a feed cylinder to move the mold back and forth in the longitudinal direction of the slab while rolling down the slab. , a position detector detects the amount of elevation of the mold, a landing recognition device detects that the mold has landed on the slab, and when the landing recognition device recognizes that the mold has landed on the slab, it sets the reduction amount. a device that outputs the set reduction amount of the slab set by the device; a device that corrects the set reduction amount of the slab set by the reduction setting device from the pressing force of the slab due to the reduction; A continuous slab reduction control device comprising a valve opening command device that outputs a command signal to a valve that controls the amount of pressurized fluid sent to the reduction cylinder.