JPH0369616B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reduction control method and device for a twin-drum continuous casting machine that continuously casts slabs between a pair of drums.

[Conventional technology]

The conventional technology will be explained with reference to FIGS. 2 and 3.

As shown in Fig. 2, the twin-drum continuous caster pours molten metal 5 such as molten steel from a tundish 2 between a pair of rotating water-cooled drums 1, 1, cools it, and produces slabs 6. Continuous casting. The slab 6 is sent out by the pinch rolls 3 and wound around the coiler 4.

FIG. 3 shows a drum pressure-down control mechanism that adjusts the distance between the water-cooled drums 1. A pair of drums 1,1
One of them is pressed against the frame 7 via bearings 10 provided at both ends, and the other is pressed by hydraulic cylinders 12a and 12b installed between the frame 7 and the bearings 10 provided at both ends. It has a structure that allows it to be rolled down. Oil at a constant pressure is supplied to each of the hydraulic cylinders 12a, 12b via a pump G and a relief valve 8, and the same pushing force is applied to both cylinders 12a, 12b. Reference numeral 11 designates side weirs that seal both sides of the space between the drums 1 and 1 in order to seal the molten metal. In normal operation of the above equipment, the slab 6
Before operation, the pressure of the relief valve 8 is set so that a predetermined pushing force is applied to the cast member, and during the casting operation, the rotation speed of the drums 1, 1 is adjusted so that the thickness of the slab 6 becomes a predetermined value. do.

[Problem that the invention seeks to solve]

Since the drum lowering device of the conventional twin-drum continuous casting machine described above operates two hydraulic cylinders independently, the parallelism of the drums is not guaranteed, resulting in the following drawbacks.

(1) Thickness differences (wedges) may occur in the slab in the width direction.

(2) Due to the inclination of the drum, a gap is created between the side weir and the end face of the drum, reducing the sealing performance of the molten metal.

The present invention seeks to solve the above problems.

[Means for solving problems]

The first invention of the present invention is a twin drum for casting a thin plate by casting molten metal between the surfaces of two drums having parallel rotation axes and rotating in opposite directions while maintaining an arbitrary distance. In a type continuous casting machine, the pressing forces at both ends of one drum are detected and summed, and a signal based on this detects and adds up the pressing forces at both ends of one drum so that the sum of the pressing forces at both ends of the other drum becomes a predetermined value. The present invention relates to a method for controlling the reduction of a twin-drum continuous casting machine that is moved in parallel by a hydraulic cylinder.

Further, the second invention relates to a reduction control device for a twin-drum continuous casting machine used for carrying out the first invention relating to the above-mentioned reduction control method, which has parallel rotating shafts and can be rotated between arbitrary intervals. two drums that hold and rotate in opposite directions; a device that detects the pressing force at both ends of one of the drums; a device that adds signals from the detection device; and a device that controls the position of the other drum. The present invention includes a hydraulic cylinder that detects the positions of both ends of the other drum, a device that detects the positions of both ends of the other drum, and a device that controls the hydraulic cylinder into which the signal from the detection device and the signal obtained by addition processing are input.

[Effect]

In the present invention, as described above, the drum position is controlled via the hydraulic cylinder by feeding back detection signals of the positions of both ends of one (the other) of the two drums to the hydraulic cylinder. , the two paired drums always maintain parallelism.

In addition, the pushing force acting on the slab by the two drums is detected at both ends of one of the drums, and by adding these together, the sum of the pushing forces is determined.
By feeding this back and controlling the other drum via the hydraulic cylinder, the two drums are kept parallel so that the sum of the pressing forces detected at both ends of one drum becomes a predetermined value. will be moved to

For this reason, the slab is cast under a predetermined pressing force, prevents wedges in the slab, and improves the sealing performance between the drum end face and the side weir, resulting in a stable cast. Casting can be done.

〔Example〕

An embodiment of the present invention will be described with reference to FIG.

In FIG. 1, parts corresponding to those of the apparatus shown in FIGS. 2 and 3 are given the same reference numerals, and their explanation will be omitted.

13a, 13b are hydraulic cylinders 12a, 13b connected to bearings 10, 10 at both ends of one drum 1;
A position detector 12b is provided on one frame 7.

14a and 14b are the position detectors 13, respectively.
Position control devices 15a and 15b to which the output signals of a and 13b are input are servo valves controlled by the position control devices 14a and 14b, respectively.

In addition, bearings 10 and 1 at both ends of the other drum 1
0 and the frame 7 are load detectors 16a, 1
6b, the output signals of the load detectors 16a and 16b are input to an adder, and the output signal of the adder is input to the pushing force control device 18. The output signal of the pushing force control device 18 is the position control device 14a,
14b.

In this embodiment, when a position command S is given to the pushing force control device 18, the servo valves 15a and 15b are driven via the position control devices 14a and 14b, and hydraulic pressure is supplied to the hydraulic cylinders 12a and 12b, so that the drum 1 is Position is controlled. Each hydraulic cylinder 1
2a, 12b, and therefore the position of the drum 1, are detected by position detectors 13a, 13b, and are sent to the position controller 14 as position feedback Sa*, Sb*.
a, 14b, and control is performed so that the position feedbacks Sa*, Sb* respectively match the position signal S, and at this time, the cylinders 12a, 12b operate in parallel to keep the drums 1, 1 parallel. Its position is controlled in the same state.

When the pushing force target value P is given to the pushing force control device 18,
The pushing force control device 18 performs an appropriate calculation (for example, PI calculation ) and outputs the position command S. Since the same position command S is simultaneously input to the position control devices 14a and 14b as described above, the hydraulic cylinders 12a and 12b are driven in parallel, and both drums 1, 1 move the other drum 1 while keeping them parallel. The distance between the two drums is changed to change the pushing force acting on the slab. The resulting pushing force changes are detected by the load detectors 16a, 16b, added in an adder 17, and fed back to the pushing force control device 18 as a pushing force feedback P* to keep both drums parallel to each other. Control is performed so that the pressing force of the drum on the slab becomes a predetermined value in this state.

As described above, according to this embodiment, the drums 1, 1
While keeping parallel to each other, the other drum moves so that the sum of the detected pressing forces at both ends of one drum becomes a predetermined value, and the pressing force of the drum on the slab can be controlled to a predetermined value. .

〔Effect of the invention〕

According to the present invention, the two drums forming a pair always remain parallel, and the pressing force of the drums on the slab can be controlled to a predetermined value.

For this reason, the present invention can bring about the following effects.

(1) It is possible to prevent the occurrence of wedges in slabs,
Product quality improves.

(2) Since the two paired drums are always kept parallel, the seal between the drums and the side weir is good and the operation is stable.

(3) Casting is performed under conditions where the pushing force that the slab receives from the drum is a predetermined value, and a product of uniform quality can be obtained.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of an embodiment of the present invention, Fig. 2 is a conceptual diagram of a conventional twin-drum continuous casting machine, and Fig. 3 is an explanatory diagram of the reduction control mechanism of a conventional twin-drum continuous casting machine. be. 1...drum, 2...tendency, 3...
Pinch roll, 4... Coiler, 5... Molten metal, 6...
... Slab, 7... Frame, 10... Bearing, 11...
...Side weir, 12a, 12b...Hydraulic cylinder,
13a, 13b...Position detector, 14a, 14b
...Position control device, 15a, 15b...Servo valve, 16a, 16b...Load detector.

Claims (1)

[Scope of Claims] 1. A twin-drum type series for casting a thin plate by casting molten metal between the surfaces of two drums that have parallel rotation axes and rotate in opposite directions while maintaining an arbitrary distance between them. In a casting machine reduction control method, the pressing forces at both ends of one drum are detected and added, and a signal based on this is used to control the pressing force of the other drum so that the sum of the pressing forces at both ends of the drum becomes a predetermined value. A method for controlling the reduction of a twin-drum continuous casting machine, characterized in that both ends are moved in parallel by hydraulic cylinders. 2. Two drums with parallel rotation axes that rotate in opposite directions while maintaining an arbitrary distance, a device that detects the pressing force at both ends of one of the drums, and a signal from the detection device. A device that performs addition processing, a hydraulic cylinder that controls the position of the other drum, a device that detects the positions of both ends of the other drum, and a device that receives the signal from the detection device and the signal subjected to the addition processing and controls the hydraulic cylinder. A reduction control method for a twin-drum continuous casting machine, characterized by comprising: