JPH0342142B2 - - Google Patents

Description

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

[Prior art] In continuous casting equipment, when a slab solidifies,
Porosities (small holes) tend 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 by using some kind of rolling device and press the porosity.

Also, during solidification, a solidification shrinkage phenomenon occurs inside the thick wall, and if left untreated, gaps will be created inside, and molten metal will flow into these gaps from the unsolidified layer, causing a phenomenon of polarization due to so-called non-uniformity of components. ing. In order to prevent deflection, a device is required to continuously reduce 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 drawn from the mold 1 (hereinafter simply referred to as slab), 2-1 is a solidified layer of slab 2, and 2-2 is an unsolidified layer. , 2-3 is a porosity (small hole), 3 is an upper pinch roll group with a plurality of rolls, 4 is a lower pinch roll group with a plurality of rolls, and on the downstream side of the upper and lower pinch roll groups 3 and 4. A continuous slab rolling down 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 vertical piston rod 7.
Four sets of the reduction cylinders 7 and 8, each with a pointing downward and a vertical piston rod 8a, are arranged as reduction cylinders, and at the lower and upper ends of the piston rods 7a and 8a, the axis line is the width of the slab 2. Wheels 9, 10 extending in the direction are rotatably pivoted.

Two sets of fluid pressure cylinders 11 parallel to the reduction cylinder 7 are disposed at the front and rear center upper part of the housing 6, and the upper ends of the piston rods 11a of the two sets of fluid pressure cylinders 11 extend parallel to the direction of movement of the slab 2. They are connected by a lever 12, and a vertically oriented rod 13 is pivotally attached to the substantially central portion of the lever 12 in the longitudinal direction, and a reduction mold main body block 14 is pivotally supported at the lower end of the rod 13.

Wheels 9 are mounted on the upper surface of the rolling die main body block 14.
A guide rail 15 that can roll is fixed to the piston rod 11a of the hydraulic cylinder 11.
By pressing upward with pressure oil, rod 1
3, the main body block 14 of the rolling die can be lifted upwardly, and the guide rail 15 can be kept in contact with the wheel 9 at all times.

Wheels 10 are mounted on the lower surface of the rolling die main body block 16 disposed below the rolling die main body block 14.
A guide rail 17 that can roll is fixed, and the rolling die main body block 16 is attached to the guide rail 17.
It is mounted on the wheel 10 via.

Liners 18 and 19 for rolling the slab 2 are removably attached to the lower or upper surfaces of the rolling mold body blocks 14 and 16, and the housing 6 is provided with liners 18 and 19 on the upstream side of the housing 6 in the moving direction of the slab 2. Beams 20 and 21 extending in the width direction are fixed, and the beam 2
The brackets 22 and 23 fixed to 0 and 21 have
Reciprocating cylinder 2 extending horizontally in the longitudinal direction of slab 2
The rear ends of the reciprocating cylinders 24 and 25 are connected to brackets 26 and 27 fixed to the rear surfaces of the reduction mold body blocks 14 and 16, respectively. At the top of both sides in the width direction, reciprocating cylinders 2
4 and 25, the reduction mold main body block 14,
Guide blocks 28 and 29 are fixed to guide the reduction mold body blocks 14 and 16 when the roll 16 is reciprocated in the longitudinal direction of the slab 2.

In Fig. 5, numerals 30 and 31 are position detectors, and it is known in Japanese Patent Application No. 60-81540 and Japanese Patent Application No. 60-77226 that the rolling down mechanism for the slab 2 and the reciprocating device are driven in conjunction with each other. has been disclosed.

In the continuous slab rolling machine 5, the rolling mold body blocks 14 and 16 are moved up and down relative to the slab by the rolling cylinders 7 and 8,
Reciprocating cylinders 24 and 25 reciprocate the slab 2 in the longitudinal direction. Therefore, by combining the movements of the reduction cylinders 7, 8 and the reciprocating cylinders 24, 25, the reduction mold body blocks 14, 1
Spatial trajectories A and A' as shown in FIG. 6 are given to 6, and the slab 2 is rolled and formed continuously in the direction of arrow X. In Fig. 6, P and P' are the sections where the rolling die body blocks 14 and 16 are advancing together with the slab 2, and S and S' are the sections where the rolling die body blocks 14 and 16 are progressing together with the slab 2.
The section where 6 moves up and down from the slab 2 and moves away from it, Q,
Q' is the period in which the rolling die main body blocks 14, 16 return to the starting position, and R, R' are the sections in which the rolling die main body blocks 14, 16 descend or rise relative to the slab 2, come into contact with the slab 2, and are rolled down. This is the section where forming is performed. Due to the reduction, for example, the porosity 2-3 gradually becomes smaller as shown in FIG.

[Problems to be Solved by the Invention] Generally, when rolling down a slab to prevent porosity or deflection of the slab, the amount of rolling needs to be done accurately to a predetermined value; Since the rolling device itself is elastically deformed and the thickness of the slab on the entrance side of the device varies, it is difficult to set the rolling amount to the correct value. In particular, the reduction mold body blocks 14, 16 are connected to the hydraulic cylinder 2, as described above.
4 and 25, when the slab 2 is reciprocated in the longitudinal direction, the landing point of the rolling die main body blocks 14 and 16 on the slab 2 in the thickness direction always changes due to dimensional errors in the thickness direction of the slab. Since it changes, the amount of reduction cannot be accurately determined. Also, the reduction mold body block 1
4 and 16 move along with the slab 2 by a certain length in the longitudinal direction of the slab 2, so the amount of reduction of the slab 2 is difficult to reach a correct value.

In view of the above-mentioned circumstances, an object of the present invention is to provide a continuous slab reduction device that can accurately control the reduction amount of slabs that have been cast in a mold and fed in a continuous manner. It is done as such.

[Means for Solving the Problems] Among the present inventions, the first invention provides an upper mold attached to the lower surface of the upper mold block, and a lower mold disposed below the upper mold block. The lower mold is attached to the upper surface of the mold block, and the lower end of the piston rod is connected to the upper mold block through a wheel that is disposed above the upper mold block and can roll about an axis extending in the width direction of the slab. A vertical reduction cylinder that contacts the upper surface and rolls down the slab downward; and a wheel that is disposed below the lower mold block and whose upper end of the piston rod can roll about an axis extending in the width direction of the slab. A vertical reduction cylinder that comes into contact with the lower surface of the lower mold block through the cylinder and lowers the slab upward; The ends of the mold blocks, which are disposed substantially parallel to each other and opposite to the upper and lower mold blocks, are connected to the upper and lower mold blocks, and reciprocate in the direction parallel to the direction in which the slab travels through the upper and lower mold blocks. a reciprocating cylinder to be moved; a pressure detector connected to a pipe line that supplies fluid to the head side fluid chamber of each of the pressure reduction cylinders; and a pressure detector connected to the pipe line and supplied to the head side fluid chamber of the pressure reduction cylinder. a control valve that controls the fluid; a landing signal generator that outputs a landing signal when the fluid pressure in the pipeline detected by the pressure detector exceeds a reference level; a position detector that detects the amount of movement; and a landing point that outputs a landing point recognition signal that determines that the mold has landed on the slab when a landing signal is given from the landing signal generator and outputs a landing point recognition signal. When a recognition device and a landing point recognition signal from the landing point recognition device are given, the amount of movement of the mold toward the center in the slab thickness direction detected by the position detector is reset to zero, and after resetting, the position is The amount of movement of the mold toward the center in the thickness direction of the slab given by the detector and the amount of movement of the mold toward the center in the thickness direction of the slab given by the displacement meter reset device after the displacement meter reset device is reset. A feedback amount calculation command device that outputs the deviation between the movement amount and the set reduction amount for the slab as a reduction feedback amount, and a valve opening command device that provides the reduction feedback amount from the feedback amount calculation instruction device as a command signal to the control valve. The second invention has an upper mold attached to the lower surface of the upper mold block, and an upper mold attached to the upper surface of the lower mold block disposed below the upper mold block. The lower end of the piston rod contacts the upper surface of the upper mold block via a wheel that is disposed above the upper mold block and that can roll about an axis extending in the width direction of the slab. The lower surface of the lower mold block is connected to a vertical reduction cylinder that rolls down the lower mold block, and a wheel that is disposed below the lower mold block and that allows the upper end of the piston rod to roll on an axis extending in the width direction of the slab. a vertically oriented lower cylinder that abuts against and presses down the slab upward; and a vertically oriented lower cylinder that is arranged approximately parallel to the direction of slab advancement in front or rear of the upper and lower mold blocks in the direction of slab advancement. a reciprocating cylinder whose ends facing the upper and lower mold blocks are connected to the upper and lower mold blocks, and which reciprocates the upper and lower mold blocks in a direction parallel to the slab traveling direction; a pressure detector connected to a pipe line that supplies fluid to the head side fluid chamber of each pressure reduction cylinder; and a control valve connected to the pipe line and controlling the fluid supplied to the head side fluid chamber of the pressure reduction cylinder. , a landing signal generator that outputs a landing signal when the fluid pressure in the pipeline detected by the pressure detector exceeds a reference level, and a position detector that detects the amount of movement of the mold toward the center in the slab thickness direction. a landing point recognition device that determines that the mold has landed on the slab when a landing signal is given from the landing signal generating device and outputs a landing point recognition signal; and landing point recognition from the landing point recognition device. When the signal is given, the amount of movement of the mold toward the center in the slab thickness direction detected by the position detector is reset to zero, and after resetting, the amount of movement of the mold in the slab thickness direction detected by the position detector is reset to zero. A displacement meter reset device outputs the amount of movement toward the center, and after the displacement meter reset device is reset, the amount of movement of the mold toward the center in the slab thickness direction given by the displacement meter reset device and the reduction on the slab an adder that calculates the deviation of the set amount; an arithmetic device that calculates the amount of elastic displacement of the mold by dividing the load detected by the load detector by a spring constant; a feedback amount calculation command device that calculates a reduction feedback amount by adding the deviations obtained by the device, and outputs the reduction feedback amount; and a valve that supplies the reduction feedback amount from the feedback amount calculation command device to the control valve as a command signal. It is equipped with an opening command device.

[Function] In the first invention, the slab is lowered while being raised and lowered by the rolling cylinder of the mold and moved in the longitudinal direction of the slab by the reciprocating cylinder. At this time, the load detected by the load detector is the standard. When the level is exceeded, a landing signal is given from the landing signal generator to the landing point recognition device, and the landing point recognition device gives the landing point recognition signal to the displacement meter reset device to reset the displacement meter reset device, and after resetting, the position is detected. The deviation between the amount of movement of the mold toward the center in the thickness direction of the slab given by the device and the set reduction amount for the slab is output as the reduction feedback amount from the feedback calculation command device, and a command signal is sent via the valve opening command device. As a result, the amount of pressurized liquid supplied to the reduction cylinder through the control valve is controlled, and the amount of reduction by the mold is controlled.

In the second invention, the mold is raised and lowered by a reduction cylinder, and the slab is rolled down while being moved in the longitudinal direction of the slab by a reciprocating cylinder, but at this time, the load detected by the load detector exceeds a reference level. The landing point recognition device then gives the landing point recognition signal to the displacement meter reset device to reset the displacement meter reset device, and after resetting, the landing point recognition device gives the landing point recognition signal to the The deviation between the amount of movement of the mold toward the center in the thickness direction of the slab and the set reduction amount for the slab is determined in the adder, and the deviation is given to the feedback amount calculation command device, and the calculation device The amount of elastic displacement of the mold is obtained by dividing the load detected by the load detector by the spring constant, and the amount of elastic displacement is given to a feedback amount calculation command device,
The feedback amount calculation command device adds the elastic displacement amount to the deviation to obtain the reduction feedback amount, and the reduction feedback amount is output from the feedback amount calculation command device and sent to the control valve as a command signal via the valve opening degree command device. As a result, the amount of pressurized liquid supplied to the reduction cylinder through the control valve is controlled, and the amount of reduction by the mold is controlled.

[Examples] Examples of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is an explanatory diagram of an embodiment of the continuous slab rolling down device of the present invention.The basic configuration is approximately the same as that shown in FIGS. 4 and 5, but in this embodiment, the slab
Various control devices are provided to control the amount of reduction to an accurate value.

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 pressure reduction cylinder 7, and 35 36 is a non-contact type position detector using an eddy current method, etc., and 37 is a guide block 28.
It is fixed outward and is a metal fitting to be detected when the position detector 36 detects the amount of up and down vertical displacement of the rolling die main body block 16. The amount of movement of the rolling die main body block 14 toward the center l side can be detected.

The pressure of the fluid supplied to the fluid pressure cylinder 7 detected by the pressure detector 34 can be applied to the landing signal generator 38 and the arithmetic unit 39. The landing signal generator 38 uses the preset reference level pressure P ₀ and the pressure P _R detected by the pressure detector 34.
When the pressure P _R is larger than the reference level pressure P ₀ , a signal can be given to the landing point recognition device 40 , and the calculation device 39 calculates the pressure P _R and the elasticity of the rolling die main body block 14 . The elastic displacement amount _{yR '} of the rolling die main body block 14 can be determined from the coefficient KR.

The position detector 36 is capable of giving a signal to a landing signal generator 41 and a displacement meter reset device 42, and the landing signal generator 41 detects when the rolling die main body block 14 has landed on the slab. If it is determined that the landing point recognition device 40
It is now possible to give to Further, the displacement X in the longitudinal direction of the rolling die main body block 14 detected by the position detectors 30 and 31 shown in FIG. When it is determined that the rolling die main body block 14 has landed on the slab 2, a landing signal can be given to the landing point recognition device 40.

The reduction amount y _R detected by the position detector 36 after the reduction mold main body block 14 lands on the slab 2
After the signal is reset to zero, it can be given to the adder ₄₄ via the displacement meter reset device 42. The deviation Δy _R of the rolling reduction amount can be determined from the set rolling reduction amount y _R0 .

The elastic displacement amount y _R ' of the rolling die main body block 14 obtained by the arithmetic unit 39 and the deviation Δy _R of the reduction amount obtained by the adder 39 are added by the feedback amount calculation command device 45 to obtain the reduction feedback amount y _R ″
can be applied to the valve opening command device 46.

The valve opening command device 46 compares and calculates the reduction feedback amount _yR '' with the amount of movement of the piston rod 7a of the reduction cylinder 7 detected by the position detector 35, and is designed to issue a valve opening command to the control valve 33. It's getting old.

The gain of the signal fed back to the valve opening command device 46 may be adjusted, for example, by adjusting the gain C of the feedback amount calculation command device 46. The continuous slab rolling down device shown in Fig. 1 is shown installed only on the left side of the left and right rolling cylinders 7, but it is also installed on the right rolling cylinder 7, and is used for lower rolling as shown in Fig. 4. It is also provided for the cylinder 8.

During operation, pressure liquid is supplied to the reduction cylinder 7,
As the piston rod 7a moves up and down, the reduction mold main body block 14 moves up and down, and the reciprocating cylinder 2
Pressure fluid is supplied to the piston rod 24a and the slab 2
By reciprocating in the longitudinal direction, the press die main body block 14 draws a spatial locus shown in FIG. Pressing is performed.

To explain the control during the reduction forming of such a slab 2 with respect to the reduction die main body block 14, when the piston rod 7a descends, the hydraulic pressure in the lower part of the reduction cylinder 7 is detected by the pressure detector 34, and the pressure is output. The pressure P _R is sent to the landing signal generator 38, and the pressure
When P _R is larger than the reference level pressure P ₀ preset in the landing signal generator 38, the landing signal generator 38 outputs a landing signal to the landing point recognition device 4.
Sent to 0. Moreover, the pressure P _R detected by the pressure detector 34 is sent to the calculation device 39.
In this case, the elastic displacement amount y _R ′ of the pressure mold main body block 14 is calculated by y _R ′=P _R /K _R , and the elastic displacement amount y _R ′ depends on the elasticity of the device itself and the reduction mold main body block 14. This is sent to the feedback amount calculation command device 45 as a corrected additional reduction amount for correcting the displacement.

On the other hand, the amount of descent of the rolling die main body block 14 that descends due to the descent of the piston rod 7a (the amount of movement of the slab 2 toward the center side l in the thickness direction D is detected by the position detector 36).
The signal is detected by the landing signal generator 41 and sent to the displacement meter reset device 42. The landing signal generating device 41 determines whether the rolling die main body block 14 has landed on the slab 2 in the following manner based on the signal from the position detector 36.
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. 14 is significantly reduced. However, as time passes, the pressure of the fluid supplied to the reduction cylinder 7 increases, and the reduction mold main body block 14 thereafter descends along a straight line C. Therefore, at a certain time, if the rolling die main body block 14 has not landed on the slab 2, the amount of descent of the rolling die main body block 14 predicted and the rolling die main body block 1
4, and if _the difference Δy _C is larger than a predetermined value Δy ₀ ,
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.

Also, the reduction mold body block 14 is reduced by the reciprocating movement of the piston rod 24a of the reciprocating cylinder 24.
The longitudinal movement x of the slab 2 is determined by the position detectors 30, 3.
1 and sent to the landing signal generator 43. The landing signal generating device 43 determines whether the rolling die main body block 14 has landed on the slab 2 in the following manner based on the signals from the position detectors 30 and 31. That is, when the rolling die main body block 14 does not land on the slab 2, as shown in FIG. Due to the speed difference between the slab 2 and the rolling die main body block 14, the rolling die main body block 14 receives a landing impact, and a movement amount x _C in the longitudinal direction of the slab occurs. Therefore, if this amount of movement x _C is larger than a predetermined value x _B , it is determined that the rolling die main body block 14 has landed on the slab 2, and the landing signal generator 43 outputs a signal. A landing signal is sent to the landing point recognition device 40.

The landing point recognition device 40 includes a landing signal generating device 3.
For example, if a landing signal is sent from any two of the landing signal generators 38, 41, and 43, the rolling die main body block 14 will move the slab 2. It is determined that the vehicle has landed on the ground, and 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 a landing signal is sent from two of the landing signal generating devices 38, 41, and 43 is because of the reduction die main body 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, and 43.

When the landing point recognition signal is applied from the landing point recognition device 40 to the displacement meter reset device 42, the signal of the amount of descent of the rolling die main body block 14 sent from the position detector 36 to the displacement meter reset device 42 is It is reset to zero, and therefore, the signal sent from the position detector 36 thereafter 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 signal of the reduction amount y _R from the position detector 36 is sent to the adder 44.
The adder 44 calculates the deviation Δy _R between the set reduction amount y _R0 set by the reduction amount setter 47 and the reduction amount y _R , and the deviation Δy _R is added to the feedback amount calculation command device 45. . In addition, since the signal of the elastic displacement amount y _R ′ calculated by the calculation device 39 is also sent to the feedback amount calculation command device 45 , the feedback amount calculation command device 45 calculates the deviation Δy _R and the elastic displacement amount y _R ′. The reduction feedback amount _yR '' is added from the command device 45 to the valve opening command device 46 as the total amount to be reduced, and the opening of the control valve 33 is controlled by the command signal from the valve opening command device 46. Therefore, the amount of pressurized liquid supplied from the control valve 33 to the reduction cylinder 7 is controlled, the piston rod 7a is lowered by a predetermined amount, and the amount of reduction by the reduction mold 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 fed back to the valve opening command device 46, and when the piston rod 7a is lowered by a predetermined amount, no command signal is output from the valve opening command device 46, and the control is stopped. Valve 33 is closed.

It should be noted that the present invention is not limited to the above-described embodiments, and it goes without saying that various changes may be made without departing from the gist of the present invention.

[Effects of the Invention] According to the continuous slab reduction device of the present invention, since the amount of slab reduction can be reliably controlled to be constant, it is possible to perform a reduction that is greater than the amount of contraction of the solidified shell. Therefore, it is possible to obtain a good slab without porosity segregation, and even if the whole device such as the housing or the mold is deformed, and the thickness of the slab changes on the entry side, the reduction of the mold against the slab can be maintained. An excellent effect can be achieved in that the amount can be accurately controlled.

[Brief explanation of drawings]

FIG. 4 is an explanatory diagram of the continuous slab rolling down device of the present invention;
Figure 2 is a graph showing the relationship between the amount of descent of the rolling die main body block and time in the apparatus of Figure 1;
The figure is a graph showing the relationship between time and the amount of movement of the rolling die main body block in the longitudinal direction of the slab in the apparatus shown in Figure 1, and Figure 4 is a schematic explanatory diagram of the continuous slab rolling apparatus that has been proposed so far. 5 is a perspective view of the same continuous slab rolling down device, and FIG. 6 is an explanatory diagram of the spatial locus of the rolling die main body block of the device of FIG. 4. In the figure, 5 is a continuous slab reduction device, 6 is a housing, 7 and 8 are reduction cylinders, 7a and 8a are piston rods, 14 and 16 are reduction mold body blocks,
24, 25 are reciprocating cylinders, 24a, 25a are piston rods, 30, 31, 35, 36 are position detectors, 32 is a liquid supply pipe (pipe line), 33 is a control valve, 3
4 is a pressure detector; 38, 41, 43 are landing signal generators; 39 is an arithmetic unit; 40 is a landing point recognition device; 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.

Claims (1)

[Claims] 1. An upper mold attached to the lower surface of the upper mold block, a lower mold attached to the upper surface of the lower mold block disposed below the upper mold block, and The piston rod is disposed above the upper mold block, and the lower end of the piston rod comes into contact with the upper surface of the upper mold block via a wheel that can roll about an axis extending in the width direction of the slab, and also rolls down the slab downward. The upper end of the piston rod comes into contact with the lower surface of the lower mold block via a vertical reduction cylinder and a wheel that is disposed below the lower mold block and can roll about an axis extending in the width direction of the slab. a vertical reduction cylinder that presses down the upper and lower mold blocks; a reciprocating cylinder whose end facing the block is connected to the upper and lower mold blocks, and which reciprocates the upper and lower mold blocks in a direction parallel to the slab advancing direction;
a pressure detector connected to a pipe line for supplying fluid to the head side fluid chamber of each pressure reduction cylinder; and a control valve connected to the pipe line and controlling fluid supplied to the head side fluid chamber of the pressure reduction cylinder. a landing signal generator that outputs a landing signal when the fluid pressure in the pipeline detected by the pressure detector exceeds a reference level; and a position that detects the amount of movement of the mold toward the center in the slab thickness direction. a detector; a landing point recognition device that determines that the mold has landed on the slab when a landing signal is given by the landing signal generating device and outputs a landing point recognition signal; When the recognition signal is given, the amount of movement of the mold toward the center in the slab thickness direction detected by the position detector is reset to zero, and after resetting, the slab thickness of the mold given by the position detector is reset to zero. A displacement meter reset device outputs the amount of movement toward the center in the direction, and after the displacement meter reset device is reset, the amount of movement of the mold toward the center in the slab thickness direction given by the displacement meter reset device and the amount of movement of the mold toward the center in the slab thickness direction are calculated. A feedback amount calculation command device that outputs the deviation of the set reduction amount as a reduction feedback amount, and a valve opening command device that provides the reduction feedback amount from the feedback amount calculation command device as a command signal to the control valve. Continuous slab rolling equipment. 2. An upper mold attached to the lower surface of the upper mold block, a lower mold attached to the upper surface of the lower mold block arranged below the upper mold block, and a lower mold attached to the upper surface of the upper mold block. a vertically oriented reduction cylinder, which is disposed in the cylinder, and whose lower end of the piston rod contacts the upper surface of the upper mold block via a wheel that can roll about an axis extending in the width direction of the slab, and which rolls down the slab downward; , which is disposed below the lower mold block, and the upper end of the piston rod comes into contact with the lower surface of the lower mold block via a wheel that can roll about an axis extending in the width direction of the slab, and rolls the slab upward. A vertical reduction cylinder is disposed in front or behind the upper and lower mold blocks in the direction in which the slab travels so as to be substantially parallel to the traveling direction, and the ends facing the upper and lower mold blocks are A reciprocating cylinder connected to the upper and lower mold blocks and reciprocating the upper and lower mold blocks in a direction parallel to the slab advancing direction, and a pipe line for supplying fluid to the head side fluid chamber of each of the reduction cylinders. a pressure detector connected to the pressure sensor, a control valve connected to the pipe line and controlling the fluid supplied to the pressure cylinder head side fluid chamber, and a fluid pressure in the pipe line detected by the pressure detector as a reference. a landing signal generator that outputs a landing signal when the level is exceeded; a position detector that detects the amount of movement of the mold toward the center in the slab thickness direction; A landing point recognition device that determines that the mold has landed on the slab and outputs a landing point recognition signal; and a landing point recognition device that outputs a landing point recognition signal when the mold has landed on the slab; and when the landing point recognition signal from the landing point recognition device is given, the mold is a displacement meter reset device that resets the amount of movement toward the center in the slab thickness direction to zero, and outputs the amount of movement of the mold given from the position detector toward the center in the slab thickness direction after the reset; After the displacement meter reset device is reset, an adder calculates the deviation between the amount of movement of the mold toward the center in the thickness direction of the slab given by the displacement meter reset device and the set reduction amount for the slab, and the load detector detects the deviation. an arithmetic device that calculates the amount of elastic displacement of the mold by dividing the applied load by a spring constant; A continuous slab reduction characterized in that it is provided with a feedback amount calculation command device that outputs a reduction feedback amount, and a valve opening degree command device that provides the reduction feedback amount from the feedback amount calculation command device as a command signal to the control valve. Device.