JP6981347B2 - Judgment system, judgment device, control method, and program - Google Patents

Description

The present invention relates to a determination system, a determination device, a control method, and a program.

As a technique for breaking a steel sheet when processing a steel sheet, Patent Document 1 discloses a method of feeding the rolled sheet and stopping the rolling mill at the same time as detecting the breakage.
Further, in Patent Document 2, when the condition such as the degree of change in the armature current of the drive motor of either the payoff reel or the tension reel exceeds the allowable maximum current change value, the plate breakage of the metal band occurs. A method for detecting plate breakage is disclosed.

Japanese Unexamined Patent Publication No. 3-248706 Japanese Unexamined Patent Publication No. 4-29052

However, when the temperature of the steel sheet is high, the temperature of the steel sheet may affect the tension detector and it may not be possible to accurately detect the breakage of the steel sheet. Further, when the breakage of the steel plate is detected by the change of the armature current, it may be erroneously detected.

An object of the present invention is to accurately detect breakage of a steel sheet.

The determination system of the present invention is a looper that is arranged in a transport path of a steel plate and includes an elevating roll that presses the steel plate from above to generate tension, and a counterbalance weight that adjusts the force with which the elevating roll presses the steel plate. And, the discharge device arranged in the transport path of the steel plate and discharging the steel plate to the looper, the pull-in device for pulling in the steel plate discharged from the looper, and the vertical position of the elevating roll are the roll reference heights. In the following cases, it is characterized by comprising a breaking determination means for determining that there is a broken portion which is an end portion of the broken steel sheet in a determination region which is a region between the discharging device and the pulling device.

According to the present invention, the breakage of the steel sheet can be accurately detected.

It is a block diagram of a control system. It is a side view of a rolling mill. It is a hardware block diagram of a control device. It is a functional block diagram of a control device. It is a figure of the front area of a casting and rolling equipment. It is a figure which shows the example of the steel plate height graph. It is a figure of the 2nd intermediate region and the rear region of a casting rolling equipment. It is a side view of a looper. It is a figure which shows the example of the looper height graph. It is a figure which shows the example of the looper height / velocity graph. It is a figure which shows the example of the current differential value graph, and the pinch roll speed graph. It is a conceptual diagram explaining a hot band. It is a figure which shows the example of the current differential value graph. It is a flowchart of a casting rolling control process. It is a flowchart of a casting machine stop control process. It is a figure which shows the state when a casting machine stops. It is a flowchart of the 1st breakage control process. It is a flowchart of the 2nd break control process. It is a flowchart of the control process at the time of rupture estimation. It is a figure which shows the state change of the casting machine in the 1st operation example. It is a figure which shows the state change of the 1st pinch roll in the 1st operation example. It is a figure which shows the state change of the 2nd pinch roll in the 1st operation example. It is a figure which shows the state change of the rolling mill in the 1st operation example. It is a figure which shows the state change of the coiler in the 1st operation example. It is a figure which shows the state change of the 1st pinch roll in the 2nd operation example. It is a figure which shows the state change of the 2nd pinch roll in the 2nd operation example. It is a figure which shows the state change of the rolling mill in the 2nd operation example. It is a figure which shows the state change of the coiler in the 2nd operation example. It is a figure which shows the state change of the rolling mill in the 3rd operation example. It is a figure which shows the state change of the rolling mill in 4th operation example.

[Control system configuration]
First, the configuration of the control system 1 will be described with reference to FIG. The control system 1 includes a casting and rolling equipment 100, a control device 500, and a network 700 connecting the casting and rolling equipment 100 and the control device 500, and casts and rolls the steel plate 10. In this embodiment, the bottom is the direction of gravity, and the top is the opposite direction of gravity. The control system 1 is an example of a determination system.
The casting and rolling equipment 100 includes a double-roll type continuous casting machine 150, a processing chamber 250, a cooling equipment 252, a camera 251, a conveyor 300, a rolling mill 350, a looper 400, and a coiler 450.

The double-roll type continuous casting machine 150 is a casting machine that manufactures a steel plate 10 from molten steel, and includes an injection unit 160 and a casting unit 200.
The injection unit 160 is a device for injecting molten steel into the casting unit 200, and includes a tundish 161 and a stopper 162.
The tundish 161 is a container that temporarily receives the molten steel injected from the ladle. The molten steel injected into the tundish 161 passes through a spout which is a through hole provided in the lower part of the tundish 161 and is injected into the hot water pool 210 of the casting portion 200.
The stopper 162 is a rod-shaped member that can open and close the spout provided at the lower part of the tundish 161, is arranged above the spout, and extends in the vertical direction. By moving the stopper 162 in the vertical direction, the amount of molten steel injected from the tundish 161 into the casting portion 200 changes. Further, when the stopper 162 moves to the lowest position and the spout of the tundish 161 is closed, the molten steel is not injected from the tundish 161 into the casting portion 200.

The casting unit 200 manufactures the steel sheet 10 from the molten steel injected from the injection unit 160. The casting section 200 includes a pair of casting rolls 201, a dam 202, a casting machine load cell 203, a casting machine power cylinder 204, a casting motor 205, and a casting machine speedometer 206.

Each of the pair of casting rolls 201 is a columnar roll and can rotate around the central axis as a rotation axis. The pair of casting rolls 201 have the same shape, and their respective axes of rotation are arranged so as to be substantially parallel to each other on the same horizontal plane. Further, a gap called a casting roll gap is provided between the pair of casting rolls 201. The pair of casting rolls 201 rotate in opposite directions so that the ends on the casting roll gap side advance downward. The area surrounded by the upper side of the cast roll gap and the weir 202 is the hot water pool 210 in which the molten steel injected from the injection portion 160 is collected.
When the pair of casting rolls 201 rotate while the molten steel is injected into the puddle 210, the casting roll 201 cools the molten steel on the surface of the casting roll 201 and solidifies it. Then, the pair of cast rolls 201 press-weld the solidified shell, which is solidified molten steel, to discharge the steel plate 10 downward from the cast roll gap.

The weir 202 is provided at both ends of the pair of casting rolls 201 in the rotation axis direction and at least above the casting roll gap to prevent molten steel from spilling from the puddle 210 in the rotation axis direction of the casting roll 201.
The casting machine load cell 203 is a load cell that is attached to one of the casting rolls 201 and measures the casting roll pressing force. The casting roll pressing force is a force by which the casting roll 201 presses the molten steel or the steel plate 10 in the casting roll gap.
The casting machine power cylinder 204 is, for example, a hydraulic servo cylinder, and a force is applied to the casting roll 201 to which the casting machine load cell 203 is not attached to change the casting roll pressing force or the casting roll gap. do.
The casting motor 205 rotates a pair of casting rolls 201.
The casting machine speedometer 206 measures the rotation speed of the casting motor 205. The measured value acquisition unit 559 of the control device 500, which will be described later, determines the casting machine speed based on the measurement result of the casting machine speedometer 206. The casting roll speed is the speed of the surface of the casting roll 201, which is the speed of the steel sheet 10 discharged from the double-roll continuous casting machine 150.

The processing chamber 250 is filled with, for example, argon gas to prevent oxidation of the steel sheet 10 discharged from the twin-roll continuous casting machine 150.
The camera 251 photographs the steel plate 10 in the processing chamber 250. The control device 500 determines the height of the steel plate, which will be described later, based on the captured image of the camera 251.
The cooling equipment 252 is arranged between the first conveyor 300A and the second conveyor 300B, which will be described later, and cools the steel plate 10 by spraying cooling water onto the steel plate 10 to be conveyed.

The transport machine 300 transports the steel plate 10 by pulling in the steel plate 10 and discharging it in the transport direction. The transport machine 300 includes a pair of pinch rolls 301, a transport machine load cell 305, a transport motor 303, a transport machine speedometer 304, a transport machine load cell 305, and an ammeter 306.
Each of the pair of pinch rolls 301 is a columnar roll, is rotatable about a central axis as a rotation axis, and is arranged so as to be arranged vertically. A gap called a pinch roll gap is provided between the pair of pinch rolls 301. The pair of pinch rolls 301 convey the steel plate 10 by passing the steel plate 10 through the pinch roll gap, sandwiching the steel plate 10, and rotating the steel plate 10 in opposite directions while pressing the surface of the steel plate 10.
The conveyor power cylinder 302 is, for example, a hydraulic servo cylinder, and applies a force to the upper pinch roll 301 to change the pinch roll pressing force or change the pinch roll gap. The pinch roll pressing force is a force by which the pinch roll 301 presses the steel plate 10.
The transport motor 303 rotates a pair of pinch rolls 301. The torque of the transfer motor 303 is proportional to the current flowing through the transfer motor 303.
The conveyor speedometer 304 measures the rotation speed of the conveyor motor 303. The measured value acquisition unit 559 of the control device 500, which will be described later, determines the pinch roll speed based on the measurement result of the conveyor speedometer 304. The pinch roll speed is the speed of the surface of the pinch roll 301, which is the speed of the steel plate 10 conveyed by the conveyor 300.
The transporter load cell 305 is a load cell that is attached to the lower pinch roll 301 and measures the pinch roll pressing force.
The ammeter 306 measures the current flowing through the transport motor 303.

The casting and rolling equipment 100 includes a first transfer machine 300A and a second transfer machine 300B as the transfer machine 300.
The first carrier 300A is arranged at a position deviated from the casting roll gap of the double roll type continuous casting machine 150 when viewed from above. The first conveyor 300A conveys the steel plate 10 by drawing in the steel plate 10 discharged from the double-roll type continuous casting machine 150 and discharging it in the direction of the second conveyor 300B. The second conveyor 300B draws in the steel plate 10 conveyed from the first conveyor 300A and discharges it in the direction of the rolling mill 350 to convey the steel plate 10 to the rolling mill 350.

Pinch roll 301 of the first conveyor 300A, conveyor power cylinder 302, conveyor electric motor 303, conveyor speed meter 304, conveyor load cell 305, current meter 306, pinch roll speed, pinch roll gap, and pinch roll pressing force. , 1st conveyor roll 301A, 1st conveyor power cylinder 302A, 1st conveyor electric motor 303A, 1st conveyor speed meter 304A, 1st conveyor load cell 305A, 1st current meter 306A, 1st pinch roll speed, respectively. It is called the first pinch roll gap and the first pinch roll pressing force.
Further, the pinch roll 301 of the second conveyor 300B, the conveyor power cylinder 302, the conveyor electric motor 303, the conveyor speed meter 304, the conveyor load cell 305, the current meter 306, the pinch roll speed, the pinch roll gap, and the pinch roll pressing. The force is applied to the second pinch roll 301B, the second conveyor power cylinder 302B, the second transport electric motor 303B, the second conveyor speed meter 304B, the second conveyor load cell 305B, the second current meter 306B, and the second pinch roll, respectively. It is called velocity, second pinch roll gap, and second pinch roll pressing force.

The rolling mill 350 rolls the steel sheet 10 transported from the second conveyor 300B. The rolling mill 350 rolls the steel sheet 10 while pulling it in, and discharges the steel sheet 10 in the transport direction. The rolling mill 350 includes a pair of rolling rolls 351 and a pair of backup rolls 352, a rolling mill power cylinder 353, a rolling motor 354, a rolling mill speedometer 355, and a rolling mill load cell 356. The rolling mill 350 is an example of a discharge device that discharges the steel plate 10.
Each of the pair of rolling rolls 351 is a columnar roll, is rotatable about a central axis as a rotation axis, and is arranged vertically side by side so that the respective rotation axes are parallel to each other. A gap called a rolling roll gap is provided between the pair of rolling rolls 351. The pair of rolling rolls 351 rolls the steel plate 10 by passing the steel plate 10 through the rolling roll gap, sandwiching the steel plate 10, and rotating the steel plates 10 in opposite directions while applying a force for pressing the steel plate 10.
Each of the pair of backup rolls 352 is a columnar roll, is rotatable about a central axis as a rotation axis, and is arranged so as to be arranged vertically with the pair of rolling rolls 351 sandwiched between them. The upper backup roll 352 is arranged above the upper rolling roll 351 so as to be in contact with the upper rolling roll 351. The lower backup roll 352 is arranged below the lower rolling roll 351 so as to be in contact with the lower rolling roll 351.

The rolling mill power cylinder 353 is, for example, a hydraulic servo cylinder, and a force is applied to the upper backup roll 352 to change the rolling mill pressing force or the rolling roll gap. A rolling mill pressing force is applied to the steel sheet 10 by the conveyor power cylinder 302 via the upper rolling roll 351. The rolling mill pressing force is a force that the rolling roll 351 presses the steel sheet 10 to roll the steel sheet 10.
The rolling motor 354 rotates a pair of rolling rolls 351.
The rolling mill speedometer 355 measures the rotational speed of the rolling motor 354. The measured value acquisition unit 559 of the control device 500, which will be described later, determines the rolling mill speed based on the measurement result of the rolling mill speedometer 355. The rolling mill speed is the speed of the surface of the rolling roll 351 and is the speed of the steel sheet 10 passing through the rolling mill 350.
The rolling mill load cell 356 is a load cell that is attached to the lower backup roll 352 and measures the rolling mill pressing force.

Here, with reference to FIG. 2, the transmission of rotation in the rolling mill 350, which is a mechanical tie type, will be described. FIG. 2 is a side view of the rolling mill 350.
The rolling motor 354 rotates the lower rolling roll 351 via the shaft 360, the first gear 361A, the first front universal joint 362A, the first spindle 363A, and the first rear universal joint 364A.
Further, the first gear 361A rotates the second gear 361B that meshes with the first gear 361A. The second gear 361B rotates the upper rolling roll 351 via the second front universal joint 362B, the second spindle 363B, and the second rear universal joint 364B.

Since the rolling mill 350 has such a configuration, the pair of rolling rolls 351 rotate at the same rotation speed. However, the diameters of the upper rolling roll 351 and the lower rolling roll 351 are different due to wear or the like. Therefore, when the pair of rolling rolls 351 are in contact with each other without rolling the steel sheet 10, a speed difference occurs in the contact portion, and torque is applied to the rolling rolls 351. Therefore, the stronger the pressing force of the rolling mill, the stronger the torque is applied to the rolling rolls 351 when the pair of rolling rolls 351 come into contact with each other, and the greater the risk of damage to the universal joint, spindle, etc. constituting the rolling mill 350.
However, in the control system 1, as will be described later, it is controlled so that the pair of rolling rolls 351 do not come into contact with each other, or even if there is a possibility of contact, they are controlled so as to come into contact with each other in a state where the pressing force of the rolling mill is weak. This reduces the risk of the rolling mill 350 being damaged.

Returning to FIG. 1, the description of the control system 1 will be continued.
The looper 400 is a counter balance weight type looper and applies tension to the steel plate 10. The looper 400 includes an elevating roll 401, a counter balance weight 402, a wire 403, a pulley 404, a first auxiliary roll 405, a second auxiliary roll 406, and a potentiometer 407.
The elevating roll 401 is movable in the vertical direction, and by placing it on the steel plate 10 to be conveyed from above, the weight of the elevating roll 401 and the force based on the weight of the counterbalance weight 402 are applied to the steel plate 10. , Tension is generated in the steel plate 10.
The counter balance weight 402 is a weight for adjusting the tension applied to the steel plate 10.

The wire 403 reaches the counter balance weight 402 from the elevating roll 401 via the pulley 404, and connects the elevating roll 401 and the counter balance weight 402. When the counter balance weight 402 is made lighter, the tension of the steel plate 10 is increased, and when the counter balance weight 402 is made heavier, the tension of the steel plate 10 is decreased.
The first auxiliary roll 405 is a roll that guides the steel plate 10 conveyed from the rolling mill 350 to the elevating roll 401, and is arranged at a preset height.
The second auxiliary roll 406 is a roll that guides the steel plate 10 that has passed through the elevating roll 401 to the coiler 450, and is arranged at a preset height.
The steel plate 10 passes through the upper side of the first auxiliary roll 405, the lower side of the elevating roll 401, and the upper side of the second auxiliary roll 406. Therefore, a force based on the weight of the elevating roll 401 and the weight of the counter balance weight 402 is applied to the steel plate 10, and tension is generated in the steel plate 10.
The potentiometer 407 measures the vertical position of the elevating roll 401. The potentiometer 407 may measure information indicating the vertical position of the elevating roll 401, such as the position of the counter balance weight 402 or the predetermined position of the wire 403.

The coiler 450 pulls in the steel plate 10 and winds up the steel plate 10. The coiler 450 includes a coiler body 451, a first coiler roll 452, a second coiler roll 453, a pressurizing unit 454, a coiler motor 455, and a coiler speedometer 456.
The coiler body 451 is a bobbin, and a steel plate 10 is wound on the side surface thereof.
The first coiler roll 452 and the second coiler roll 453 are arranged below the coiler body 451 and support the coiler body 451. Further, by rotating the first coiler roll 452 and the second coiler roll 453, the steel plate 10 between the first coiler roll 452 and the second coiler roll 453 and the coiler body 451 is wound around the coiler body 451. Let me.
The pressurizing unit 454 applies a downward coiler pressing force to the coiler body 451 and presses the coiler body 451 against the first coiler roll 452 and the second coiler roll 453 to stabilize the coiler body 451.
The coiler motor 455 rotates the first coiler roll 452 and the second coiler roll 453.
The coiler speedometer 456 measures the rotation speed of the coiler motor 455. The measured value acquisition unit 559 of the control device 500, which will be described later, determines the coiler speed based on the measurement result of the coiler speedometer 456. The coiler speed is the speed on the surface of the first coiler roll 452, which is the speed at which the coiler 450 winds up the steel sheet 10.
The conveyor 300 and the coiler 450 are examples of a pull-in device for pulling in the steel plate 10.

Next, the transport path of the steel plate 10 in the casting and rolling equipment 100 will be described. First, the steel plate 10 is discharged from between the pair of casting rolls 201 of the twin-roll continuous casting machine 150, for example, at 1600 ° C. Next, the steel plate 10 passes between the pair of first pinch rolls 301A of the first conveyor 300A and between the pair of second pinch rolls 301B of the second conveyor 300B, and the pair of rolling machines of the rolling mill 350 is rolled. It is rolled between rolls 351 and discharged to the looper 400 at, for example, 1000 ° C. Next, the steel plate 10 passes under the elevating roll 401 of the looper 400 and is wound by the coiler 450.

Next, the front region 601, the first intermediate region 602, the second intermediate region 603, and the rear region 604 in the casting and rolling equipment 100 will be described.
The front region 601 is an region between the double roll type continuous casting machine 150 and the first conveyor 300A. More specifically, the front region 601 is a region between the casting roll gap of the double roll type continuous casting machine 150 and the first pinch roll gap of the first conveyor 300A.
The first intermediate region 602 is an region between the first transport machine 300A and the second transport machine 300B. More specifically, the first intermediate region 602 is a region between the first pinch roll gap of the first conveyor 300A and the second pinch roll gap of the second conveyor 300B.
The second intermediate region 603 is an region between the second conveyor 300B and the rolling mill 350. More specifically, the second intermediate region 603 is a region between the second pinch roll gap of the second conveyor 300B and the rolling roll gap of the rolling mill 350.
The rear region 604 is an region between the rolling mill 350 and the coiler 450. More specifically, the rear region 604 is a region between the rolling roll gap of the rolling mill 350 and the coiler 450. The rear region 604 is an example of a determination region.

Next, the hardware configuration of the control device 500 will be described with reference to FIG. FIG. 3 is a hardware configuration diagram of the control device 500. The control device 500 is an example of a determination device.
The control device 500 is a computer such as a PLC (programmable logic controller) that controls the casting and rolling equipment 100, and includes a CPU 501, a storage device 502, a module 503, and a bus 504 connecting them.
The CPU 501 controls the entire control device 500. When the CPU 501 executes the process based on the program stored in the storage device 502 or the like, the function of the control device 500 shown in FIG. 4 and the processes of FIGS. 14, 15, 17 to 19 are realized. ..

The storage device 502 is a RAM, ROM, HDD, or the like, and stores a program or temporarily stores data used by the CPU 501.
The module 503 controls the apparatus of the casting and rolling equipment 100 associated with the module 503 via the network 700 based on the command from the CPU 501. There are a plurality of modules included in the control device 500, and each module 503 is associated with a device of a casting and rolling facility 100 such as a rolling motor 354 and a rolling mill load cell 356. The module 503 may directly control the equipment of the casting and rolling equipment 100 based on the command from the CPU 501, and control the equipment of the casting and rolling equipment 100 via an inverter or the like corresponding to the equipment of the casting and rolling equipment 100. May be done.

The control device 500 has a function of virtually dividing the CPU 501, and can perform parallel processing. Further, the CPU 501 can acquire the information of the measuring instrument of the casting and rolling equipment 100 via the module 503 corresponding to the measuring instrument. The CPU 501 may acquire the information of the measuring instrument of the casting and rolling equipment 100 from the measuring instrument of the casting and rolling equipment 100 via the communication interface included in the control device 500. The measuring instrument of the casting / rolling equipment 100 is a device for acquiring various information of the casting / rolling equipment 100, such as a camera 251, a load cell such as a casting machine load cell 203, a speedometer such as a casting machine speedometer 206, and a current. A total of 306 is included.

Next, the function of the control device 500 will be described with reference to FIG. FIG. 4 is a functional configuration diagram of the control device 500. The control device 500 passes through the casting machine control unit 550, the molten steel control unit 551, the rolling mill control unit 552, the coiler control unit 555, the conveyor control unit 554, the fracture determination unit 555, and the estimation unit 556. It includes a determination unit 557, a processing management unit 558, and a measured value acquisition unit 559.
The casting machine control unit 550 controls the casting motor 205 via the module 503 to control the casting roll speed. Further, the casting machine control unit 550 controls the casting machine power cylinder 204 via the module 503 to control the casting roll pressing force and the casting roll gap.

The molten steel control unit 551 controls the position of the stopper 162 via the module 503.
The rolling mill control unit 552 controls the rolling mill 354 via the module 503 to control the rolling mill speed. Further, the rolling mill control unit 552 controls the rolling mill power cylinder 353 via the module 503 to control the rolling mill pressing force and the rolling roll gap.
The coiler control unit 553 controls the coiler motor 455 via the module 503 to control the coiler speed. Further, the coiler control unit 553 controls the pressurizing unit 454 via the module 503 to control the coiler pressing force.

The transport machine control unit 554 controls the first transport motor 303A and the second transport motor 303B via the module 503 to control the first pinch roll speed and the second pinch roll speed. Further, the transporter control unit 554 controls the first transporter power cylinder 302A and the second transporter power cylinder 302B via the module 503, and controls the first pinch roll gap, the second pinch roll gap, and the first. The pinch roll pressing force and the second pinch roll pressing force are controlled.
The fracture determination unit 555 determines whether or not the steel plate 10 is fractured in the front region 601. Further, the fracture determination unit 555 determines whether or not there is a fracture portion of the steel plate 10 in the rear region 604. The broken portion of the steel plate 10 is an end portion of the broken steel plate 10.
The estimation unit 556 estimates whether or not the steel sheet 10 is broken in the first intermediate region 602 or the second intermediate region 603.

The passage determination unit 557 determines whether or not the broken portion of the steel plate 10 has passed through the first transfer machine 300A or the second transfer machine 300B. More specifically, the passage determination unit 557 determines whether or not the broken portion of the steel plate 10 has passed through the first pinch roll gap or the second pinch roll gap.
The processing management unit 558 controls the operation of each function of the control device 500.
The measured value acquisition unit 559 acquires the measured value from the measuring instrument of the casting and rolling equipment 100.

[Break of steel plate in the front area]
Next, the breakage of the steel plate 10 in the front region 601 will be described with reference to FIGS. 5 (a) and 5 (b). FIG. 5A is a conceptual diagram of the front region 601 before the steel plate 10 breaks in the front region 601. FIG. 5B is a conceptual diagram of the front region 601 after the steel plate 10 is broken in the front region 601.
As shown in FIG. 5A, before the steel sheet 10 breaks in the front region 601 the steel sheet 10 discharged from the double-roll continuous casting machine 150 first moves downward and then moves backward. It is lifted and proceeds to the first conveyor 300A. The rear side is the transport direction of the steel plate 10, and is the direction from the double-roll type continuous casting machine 150 to the first transport machine 300A when the casting and rolling equipment 100 is viewed from above.

As shown in FIG. 5A, consider a case where the steel plate 10 is broken in the region of the steel plate 10 immediately after being discharged from the double-roll type continuous casting machine 150 in the front region 601. In this case, when the double-roll type continuous casting machine 150 continues to discharge the steel plate 10, the steel plate 10 is broken. Therefore, as shown in FIG. 5 (b), the processing chamber is at the lowest position in the front region 601. Reach 250 floors 253. Therefore, the fracture determination unit 555 can determine whether or not the steel plate 10 is fractured in the front region 601 based on the lowermost position of the steel plate 10 in the front region 601.

Next, the steel plate height 21 in the front region 601 will be described with reference to FIGS. 5A and 5B. The steel plate height 21 is the lowest position in the vertical direction of the steel plate 10 connected to the cast roll gap in the front region 601. As shown in FIG. 5A, when the steel plate 10 is not broken in the front region 601 the steel plate height 21 is above the floor 253. As shown in FIG. 5B, when the steel plate 10 is broken in the front region 601 the steel plate height 21 becomes the same height as the floor 253.
The camera 251 photographs the steel plate 10 in the front region 601. The measured value acquisition unit 559 analyzes the image of the steel plate 10 taken by the camera 251 to acquire the steel plate height 21. The height 21 of the steel plate is determined with reference to the position 20 in the vertical direction in which the camera 251 is arranged. In the present embodiment, the steel plate height 21 is represented as a positive value when it is above the position 20 of the camera 251 and as a negative value when the steel plate height 21 is below the position 20 of the camera 251.

Next, with reference to FIG. 6, a method for determining whether or not the steel plate 10 is fractured in the front region 601 by the fracture determination unit 555 will be described. FIG. 6 is a diagram showing an example of a steel plate height graph showing a time change of the steel plate height 21. The line 30 represents the first reference height. The first reference height is a preset value, and is a height that serves as a threshold value indicating that the steel plate 10 is broken in the front region 601. The first reference height is set to a height below the casting roll gap of the double roll type continuous casting machine 150. The first reference height may be the height of the floor 253, or may be set higher than the height of the floor 253 in consideration of an error of the steel plate height 21 acquired by the measured value acquisition unit 559.
The fracture determination unit 555 determines that the steel plate 10 has broken in the front region 601 when the steel plate 10 reaches the first reference height, that is, when the steel plate height 21 becomes equal to or less than the first reference height. .. In the present embodiment, in order to prevent erroneous determination, the fracture determination unit 555 is in a state where the steel plate 10 reaches the first reference height during the preset first reference time. When it continues, it is determined that the steel plate 10 is broken in the front region 601.
In the example of FIG. 6, it is shown that the steel plate 10 is broken in the front region 601 at time 11 (sec). As shown in FIG. 6, after the steel plate 10 is broken, the height of the steel plate 21 sharply decreases and reaches the first reference height. Therefore, the fracture determination unit 555 can determine that the steel plate 10 is fractured immediately after the steel plate 10 is fractured in the front region 601.

[Break of steel sheet in areas other than the front area]
Next, with reference to FIGS. 7 (a) to 7 (d), the fracture of the steel sheet 10 in the second intermediate region 603, which is a region other than the front region, will be described. FIG. 7A is a diagram of the second intermediate region 603 before the steel plate 10 breaks in the second intermediate region 603 and the rear region 604. FIG. 7B is a diagram of the second intermediate region 603 and the rear region 604 after the steel plate 10 is broken in the second intermediate region 603. FIG. 7C is a diagram of the second intermediate region 603 and the rear region 604 when the fractured portion 15 reaches the rear region 604. FIG. 7D is a diagram of the second intermediate region 603 and the rear region 604 after the fractured portion 15 reaches the rear region 604.

First, as shown in FIG. 7A, it is assumed that the steel plate 10 is broken in the second intermediate region 603. In this case, as shown in FIG. 7B, the broken portion 15 of the steel plate 10 on the coiler 450 side moves in the direction of the rolling mill 350 by the rotation of the rolling roll 351.
After that, as shown in FIG. 7 (c), the fractured portion 15 passes through the rolling mill 350 and reaches the rear region 604 by the operation of winding the steel sheet 10 by the coiler 450. When the broken portion 15 reaches the rear region 604, the steel plate 10 is not sandwiched by the rolling roll 351 of the rolling mill 350, so that the elevating roll 401 falls to the lower limit position of the elevating roll 401 by its own weight. At this time, the counter balance weight 402 is pulled by the elevating roll 401 via the pulley 404 and moves upward. The lower limit position of the elevating roll 401 is the lowest position that the elevating roll 401 can take in the looper 400.

When the elevating roll 401 falls to the lower limit position of the elevating roll 401, as shown in FIG. 7D, the impact of the dropping of the elevating roll 401 causes the steel plate 10 to break between the looper 400 and the coiler 450. There is.
When the steel plate 10 is broken in the rear region 604, the elevating roll 401 also falls as shown in FIG. 7 (c). Therefore, the fracture determination unit 555 can determine whether or not the fractured portion 15 of the steel plate 10 is present in the rear region 604 based on the position in the vertical direction of the elevating roll 401. The condition that the steel plate 10 has a fractured portion 15 in the rear region 604 is satisfied when the fractured portion 15 reaches the rear region 604 after the steel plate 10 is fractured in the first intermediate region 602 or the second intermediate region 603. , At least one of the cases where the steel plate 10 is broken in the rear region 604.

Next, the looper height 41 will be described with reference to FIG. FIG. 8 is a side view of the looper 400. The looper height 41 is a position in the vertical direction of the elevating roll 401, and represents the height of the elevating roll 401. The looper height 41 is determined with reference to a preset vertical position 40. In the present embodiment, the looper height 41 is represented as a positive value when it is above the position 40 and as a negative value when it is below the position 40. The looper height 41 is measured by the potentiometer 407.

Next, with reference to FIG. 9, a method for determining whether or not the fractured portion 15 of the steel plate 10 is present in the rear region 604 by the fracture determination portion 555 will be described. FIG. 9 shows an example of a looper height graph showing a change in looper height over time. The line 31 represents the second reference height. The second reference height is a preset value, and is a height that serves as a threshold value indicating that the fractured portion 15 is in the rear region 604.
The fracture determination unit 555 determines that the fractured portion 15 of the steel plate 10 is present in the rear region 604 when the looper height 41 becomes equal to or less than the second reference height. In the present embodiment, in order to prevent erroneous determination, in the fracture determination unit 555, the steel plate 10 is in a state where the looper height 41 is equal to or less than the second reference height during the preset second reference time. When it continues, it is determined that there is a broken portion 15 of the steel plate 10 in the rear region 604. The second reference height is an example of the roll reference height.
In the example of FIG. 9, after time 12.9 (sec), as shown in FIG. 7 (c), the fractured portion 15 reaches the rear region 604, or the steel plate 10 fractures in the rear region 604. , Indicates that the fractured portion 15 is present in the rear region 604. At this time, as shown in FIG. 9, the looper height decreases after the time is 12.9 (sec), and the looper height reaches the second reference height at the time 13.15 (sec). Therefore, the fracture determination unit 555 can determine that the fractured portion 15 of the steel plate 10 is present in the rear region 604 at time 13.15 (sec).

Next, a method of determining the second reference height will be described with reference to FIG. FIG. 10 is a diagram showing an example of a looper height / velocity graph showing changes in looper height, coiler speed, and first pinch roll speed over time. The first line 50 represents the coiler speed (mpm (meters / minute)), the second line 51 represents the first pinch roll speed (mpm), and the third line 52 represents the looper height (mm). In FIG. 10, the first line 50 and the second line 51 substantially coincide with each other.
The looper height / speed graph of FIG. 10 shows a state in which rolling is normally performed by the rolling mill 350 without causing breakage in the steel sheet 10.
The second reference height is the lower limit of the normal range of the looper height. The normal range of the looper height is a range in which the looper height is contained when rolling is normally performed by the rolling mill 350. The lower limit of the normal range of the looper height is a value representing the lowermost part of the normal range of the looper height. In the example of FIG. 10, the looper height is within the range of +100 (mm) to -100 (mm), but the normal range of the looper height is changed from +150 (mm) in consideration of changes in operating conditions. It is defined as up to -150 (mm). Therefore, in the example of FIG. 10, the second reference height is −150 (mm).

[Estimation of steel plate breakage]
Next, referring to FIGS. 11A and 11B, whether or not the steel plate 10 is broken in the first intermediate region 602 by the estimation unit 556 based on the amount of change in the current flowing through the first transport motor 303A. The method of estimating the current will be described. FIG. 11A is a diagram showing an example of a current differential value graph showing a time change of the current differential value of the first transport motor 303A. The current differential value of the first transfer motor 303A is a value obtained by differentiating the value of the current flowing through the first transfer motor 303A. FIG. 11B is a diagram showing an example of a pinch roll speed graph showing a time change of the first pinch roll speed.

In FIGS. 11A and 11B, the casting and rolling equipment 100 is in a steady casting state from time 0 (sec) to time 12 (sec), and at time 12 (sec), the steel plate 10 is formed in the first intermediate region 602. Is shown to have broken. The steady casting state of the casting and rolling equipment 100 is a state in which the steel plate 10 is not broken in the casting and rolling equipment 100, and casting by the double-roll type continuous casting machine 150 and rolling by the rolling mill 350 are normally performed. be. 11 (a) and 11 (b) are graphs obtained by a simulation modeling the casting and rolling equipment 100.

When the casting and rolling equipment 100 is in a steady casting state, the speed of the steel plate 10 is substantially constant. Further, the tension of the steel plate 10 is also kept substantially constant, and the torque of the first transport motor 303A for rotating the first pinch roll 301A is also substantially constant. Here, as already described, the torque of the first transport motor 303A is proportional to the value of the current flowing through the first transport motor 303A. Therefore, when the casting and rolling equipment 100 is in the steady casting state, the current of the first transfer motor 303A is almost constant, so that the current differential value of the first transfer motor 303A is almost zero.

When the steel plate 10 breaks in the first intermediate region 602, the tension of the steel plate 10 suddenly decreases, and the torque applied to the first transport motor 303A fluctuates greatly. Therefore, since the current of the first transport motor 303A also fluctuates greatly, the current differential value of the first transport motor 303A also fluctuates greatly. Also in the example of FIG. 11A, it can be seen that the current differential value of the first transport motor 303A fluctuates greatly in a pulse shape at the time 12 (sec) when the steel plate 10 breaks in the first intermediate region 602.
Further, when the steel plate 10 breaks in the first intermediate region 602, the first pinch roll speed greatly fluctuates due to the impact that the tension of the steel plate 10 suddenly fluctuates. Also in the example of FIG. 11B, when the steel plate 10 is broken at the time 12 (sec) in the first intermediate region 602, the pinch roll speed of the first pinch roll 301A fluctuates greatly.

From such a fact, the estimation unit 556 estimates whether or not the steel plate 10 is broken in the first intermediate region 602 based on the amount of change in the current flowing through the first transfer motor 303A acquired from the first ammeter 306A. do. More specifically, the estimation unit 556 estimates that the steel plate 10 is broken in the first intermediate region 602 when the current differential value of the first transport motor 303A becomes equal to or greater than the change amount threshold value. The change amount threshold value is a preset value, and is a value that serves as a threshold value for estimating the breakage of the steel plate 10 by the current differential value of the first transfer motor 303A. The change amount threshold value is determined based on the current differential value graph shown in FIG. 11 (a). In the example of FIG. 11A, the change amount threshold is set to, for example, 1000 (A / sec).

After the steel plate 10 is broken in the first intermediate region 602, the current differential value of the first transport motor 303A approaches 0 as shown in FIG. 11A, and the pinch roll speed of the first pinch roll 301A is shown in FIG. As shown in 11 (b), it approaches a constant speed.
Here, the time from the start of the pulse-shaped fluctuation of the pinch roll speed due to the breakage of the steel plate 10 to the subsidence of the pulse-shaped fluctuation is called the hunting convergence time. From the example of FIG. 11B, the hunting convergence time can be set to, for example, 0.5 (sec).

Next, the estimation unit 556 determines whether or not the steel plate 10 is broken in at least one of the first intermediate region 602 and the second intermediate region 603 based on the amount of change flowing in the current of the second transport motor 303B. The method of estimation will be described.
When the steel plate 10 is broken in at least one of the first intermediate region 602 and the second intermediate region 603, the current differential value of the second transfer motor 303B and the second pinch roll speed are shown in FIG. 11A. The values are the same as those of the current differential value graph and the pinch roll speed graph as shown in (b). This is because when the steel plate 10 breaks in at least one of the first intermediate region 602 and the second intermediate region 603, the change in the tension of the steel plate 10 is transmitted to the second pinch roll 301B and the torque of the second transport motor 303B is increased. This is because it fluctuates.
The estimation unit 556 breaks the steel plate 10 in at least one of the first intermediate region 602 and the second intermediate region 603 based on the amount of change in the current flowing through the second transport motor 303B acquired from the second ammeter 306B. Estimate whether or not it was done. More specifically, the estimation unit 556 describes the steel plate 10 in at least one of the first intermediate region 602 and the second intermediate region 603 when the current differential value of the second transport motor 303B becomes equal to or greater than the change amount threshold value. Is presumed to have broken.

Next, the estimation unit 556 will explain the possibility of presuming that the steel plate 10 is erroneously broken even though the steel plate 10 is not broken.
First, the hot band 13 of the steel plate 10 as an example of the disturbance will be described with reference to FIGS. 12 (a), 12 (b), and (c). FIG. 12A is a perspective view of the casting portion 200 of the double-roll type continuous casting machine 150. FIG. 12B is a plan view of the casting portion 200. FIG. 12 (c) is a perspective view of the steel plate 10 on which the hot band 13 is formed.
As shown in FIG. 12 (c), the hot band 13 is a thick portion of the steel plate 10 formed by the metal 12 on the side surface of the weir 202 entering during casting. In the bullion 12 on the side surface of the weir 202 as shown in FIG. 12A, the molten steel 11 adhering to the side surface of the weir 202 solidifies due to fluctuations in the molten metal level (surface height of the molten steel 11) during casting or the like. It is formed by.
The bullion 12 on the side surface of the weir 202 may peel off from the weir 202 due to an impact during casting or the like and may enter between the pair of casting rolls 201 as shown in FIG. 12 (b). When the bullion 12 entered between the pair of casting rolls 201, the hardness of the bullion 12 widened the space between the pair of casting rolls 201, forming a hot band 13 as shown in FIG. 12 (c). The steel plate 10 is discharged from the double roll type continuous casting machine 150.

Next, with reference to FIG. 13, an example in which the estimation unit 556 presumes that the steel plate 10 is erroneously broken will be described. FIG. 13 is a diagram showing an example of a current differential value graph of the first transport motor 303A. FIG. 13 is a graph obtained by a simulation modeling the casting and rolling equipment 100.
FIG. 13 shows an example in which the hot band 13 of the steel plate 10 passes between the pair of first pinch rolls 301A at time 11 (sec).
When the hot band 13 of the steel plate 10 passes through the first pinch roll 301A, the distance between the pair of first pinch rolls 301A suddenly fluctuates. Due to this fluctuation, the torque of the first transport motor 303A that rotates the first pinch roll 301A suddenly fluctuates. Therefore, as shown in the vicinity of time 11 (sec) in FIG. 13, the current of the first transport motor 303A fluctuates abruptly, and the current differential value of the first transport motor 303A fluctuates greatly.
Depending on the size of the hot band 13 and the speed of the steel plate 10, when the hot band 13 passes through the first pinch roll 301A, the current differential value of the first transport motor 303A may exceed the change amount threshold value. In this case, the estimation unit 556 presumes that the steel plate 10 is erroneously broken.

Next, a method of determining whether or not the broken portion 15 of the steel plate 10 has passed through the first conveyor 300A by the passing determination unit 557 after the steel plate 10 is broken in the front region 601 will be described.
After the steel plate 10 is broken in the front region 601 the steel plate 10 located on the side of the first conveyor 300A with respect to the broken portion 15 is conveyed to the side of the coiler 450, and after a lapse of time, the broken portions 15 are paired. It passes between the first pinch rolls 301A. When the broken portion 15 passes between the pair of first pinch rolls 301A, the steel plate 10 does not exist between the pair of first pinch rolls 301A, so that the first transport motor 303A for rotating the first pinch roll 301A Torque fluctuates abruptly. Therefore, similarly to FIGS. 11A and 13, the current differential value of the first transport motor 303A fluctuates greatly.

From such a fact, the passage determination unit 557 allows the broken portion 15 of the steel plate 10 to pass through the first transfer machine 300A based on the amount of change in the current flowing through the first transfer motor 303A acquired from the first ammeter 306A. Judge whether or not. More specifically, the passage determination unit 557 determines that the break portion 15 has passed between the pair of first pinch rolls 301A when the current differential value of the first transfer motor 303A becomes equal to or higher than the transfer threshold value. The transport threshold value is a preset value, and is a threshold value indicating that the break portion 15 has passed between the pair of pinch rolls 301. The transport threshold is determined based on the current differential value graph as shown in FIG. 11A when the break portion 15 passes between the pair of pinch rolls 301. In this embodiment, the transport threshold is set to 500 (A / sec). Similarly, the passage determination unit 557 determines whether or not the broken portion 15 of the steel plate 10 has passed through the second transfer machine 300B based on the amount of change in the current flowing through the second transfer motor 303B acquired from the second ammeter 306B. Is determined.

[Casting and rolling control processing]
Next, the casting and rolling control process will be described with reference to FIG. FIG. 14 is a flowchart of the casting and rolling control process. The casting / rolling control process is a process of controlling the casting / rolling equipment 100 to cast and roll the steel sheet 10.
In step S100, the processing management unit 558 acquires various parameters of the casting and rolling equipment 100 by referring to the storage device 502 or receiving information from an external device by network communication. Then, the processing management unit 558 initially sets the casting and rolling equipment 100 so as to perform operations corresponding to the acquired various parameters. The various parameters acquired by the processing control unit 558 include target parameters representing the target values in the steady casting state. The target parameters include a target casting parameter representing the casting target of the double-roll continuous casting machine 150 and a target rolling parameter representing the rolling target of the rolling mill 350. The target rolling mill pressing force included in the target rolling parameters is, for example, 200 (tonf), and the target first pinch roll pressing force and the second pinch roll pressing force are, for example, 1 (tonf). ..

In step S101, the casting machine control unit 550 and the molten steel control unit 551 start controlling the double roll type continuous casting machine 150 based on the target parameters. Further, the rolling mill control unit 552 starts controlling the rolling mill 350 based on the target parameter. Further, the transport machine control unit 554 starts controlling the transport machine 300 based on the target parameter. Further, the coiler control unit 553 starts controlling the coiler 450 based on the target parameter. In this way, casting and rolling are started, and the casting and rolling equipment 100 is in a steady casting state.
In step S102, the processing management unit 558 controls to start the processing of step S103, step S108, and step S113 in parallel.

In step S103, the measured value acquisition unit 559 acquires the steel plate height 21 based on the image taken by the camera 251. The fracture determination unit 555 determines whether or not the steel plate 10 is fractured in the front region 601 between the double roll type continuous casting machine 150 and the first conveyor 300A based on the steel plate height 21. More specifically, as described with reference to FIG. 6, in the fracture determination unit 555, the steel plate 10 continues for a preset first reference time, and the steel plate height 21 is the first reference. When it is equal to or less than the height, it is determined that the steel plate 10 is broken in the front region 601.
When the fracture determination unit 555 determines that the steel plate 10 is fractured in the front region 601 the processing proceeds to step S104, and when it is determined that the steel sheet 10 is not fractured, the fracture determination unit 555 executes step S103 again.

In step S104, the process management unit 558 controls to start the processes of step S105 and step S106 in parallel.
In step S105, the control device 500 executes the casting machine stop control process described later.
In step S106, the control device 500 executes the first break control process described later.
In step S107, the processing management unit 558 ends the processing of FIG. 14 after the processing of steps S105 and S106 is completed.

In step S108, the measured value acquisition unit 559 acquires the looper height 41 from the potentiometer 407. Then, the fracture determination unit 555 determines whether or not there is a fracture portion in the rear region 604, which is a region between the rolling mill 350 and the coiler 450, based on the looper height 41. More specifically, as described with reference to FIG. 9, in the fracture determination unit 555, the steel plate 10 continues for a preset second reference time, and the looper height 41 is the second reference. When it is equal to or less than the height, it is determined that there is a broken portion of the steel plate 10 in the rear region 604.
When the fracture determination unit 555 determines that the steel plate 10 has a fracture portion in the rear region 604, the process proceeds to step S109, and when it is determined that the rear region 604 has no fracture portion of the steel plate 10, step S108 is executed again. ..

In step S109, the process management unit 558 controls to start the processes of step S110 and step S111 in parallel.
In step S110, the control device 500 executes the casting machine stop control process described later.
In step S111, the control device 500 executes the second break control process described later.
In step S112, the processing management unit 558 ends the processing of FIG. 14 after the processing of step S110 and step S111 is completed.

In step S113, the process management unit 558 controls to start the processes of step S114 and step S115 in parallel.
In step S114, the measured value acquisition unit 559 acquires the value of the current flowing from the first ammeter 306A to the first transfer motor 303A. The estimation unit 556 is used in the first intermediate region 602 between the first transfer machine 300A and the second transfer machine 300B based on the amount of change in the current flowing through the first transfer motor 303A acquired by the measurement value acquisition unit 559. , Estimate whether or not the steel plate 10 is broken. More specifically, as described above, the estimation unit 556 estimates that the steel plate 10 is broken in the first intermediate region 602 when the current differential value of the first transport motor 303A becomes equal to or higher than the change amount threshold value. do.
The estimation unit 556 advances the process to step S116 when it is estimated that the steel plate 10 is broken in the first intermediate region 602, and executes step S114 again when it is not estimated that the steel plate 10 is broken in the first intermediate region 602.

In step S115, the measured value acquisition unit 559 acquires the value of the current flowing from the second ammeter 306B to the second transfer motor 303B. The estimation unit 556 has a first intermediate region 602 between the first transfer machine 300A and the second transfer machine 300A, based on the amount of change in the current flowing through the second transfer motor 303B acquired by the measurement value acquisition unit 559. And, it is estimated whether or not the steel plate 10 is broken in at least one of the second intermediate regions 603 between the second conveyor 300A and the rolling mill 350. More specifically, as described above, the estimation unit 556 describes the first intermediate region 602 and the second intermediate region 603 when the current differential value of the second transport motor 303B becomes equal to or higher than the change amount threshold value. It is presumed that the steel plate 10 is broken by at least one of the above.
When the estimation unit 556 estimates that the steel sheet 10 is broken in at least one of the first intermediate region 602 and the second intermediate region 603, the processing proceeds to step S116, and the first intermediate region 602 and the second intermediate When it is not estimated that the steel plate 10 is broken in at least one of the regions 603, step S115 is executed again.

In step S116, the process management unit 558 proceeds to step S117 when the process proceeds to step S116 from either step S114 or step S115.
In step S117, the rolling mill control unit 552 executes the fracture estimation time control process described later. After that, the process returns to step S113.

Next, the casting machine stop control process will be described with reference to FIGS. 15A and 16D. FIG. 15 is a flowchart of the casting machine stop control process. 16 (a) to 16 (d) are views showing a state when the double-roll type continuous casting machine 150 is stopped.
In step S200, the molten steel control unit 551 controls to stop the injection of the molten steel 11 into the hot water pool 210. More specifically, the molten steel control unit 551 controls the stopper 162 to close the spout of the tundish 161. As a result, as shown in FIG. 16A, the stopper 162 moves downward, the spout of the tundish 161 is closed, and the injection of the molten steel 11 into the puddle 210 is stopped.
In step S201, the casting machine control unit 550 controls to reduce the rotation speed of the casting roll 201. More specifically, the casting machine control unit 550 reduces the rotation speed of the casting electric machine 205 so that the casting roll speed is slower than the casting roll speed for satisfying the casting target, and reduces the rotation speed of the casting roll 201. By lowering it, the casting roll speed is controlled to be lowered.

In step S202, the casting machine control unit 550 determines whether or not the discharge time has elapsed since the process of step S201 was performed. The discharge time is a preset time as the time until the molten steel 11 accumulated in the hot water pool 210 is discharged from the hot water pool 210. The casting machine control unit 550 advances the process to step S203 when the discharge time has elapsed, and executes step S202 again when the discharge time has not elapsed.
By stopping the injection of the molten steel 11 into the puddle 210, the amount of the molten steel 11 in the puddle 210 decreases, as shown in FIG. 6B. As the discharge time elapses, the molten steel 11 disappears from the puddle 210, as shown in FIG. 6 (c).

In step S203, the casting machine control unit 550 controls to stop the rotation of the casting motor 205 and stop the rotation of the casting roll 201.
In step S204, the casting machine control unit 550 controls to open the casting roll 201. More specifically, as shown in FIG. 6D, the casting machine control unit 550 controls the casting machine power cylinder 204 to widen the distance between the pair of casting rolls 201, and the pair of casting rolls 201. Control so that the distance between them is maximized. The double-roll continuous casting machine 150 of the present embodiment automatically moves so that the distance between the pair of casting rolls 201 is maximized when the power is turned off. Since the distance between the pair of casting rolls 201 is maximized in advance in step S204, it is possible to avoid a situation in which the distance between the pair of casting rolls 201 suddenly increases even if the power is turned off.

Next, the first fracture control process will be described with reference to FIG. FIG. 17 is a flowchart of the first fracture control process.
In step S300, the conveyor control unit 554 controls to reduce the rotation speed of the first pinch roll 301A and the second pinch roll 301B. More specifically, the transporter control unit 554 is based on the first pinch roll speed and the second pinch roll speed at which the second pinch roll speed is the target value in the steady casting state. Control is performed to reduce the rotation speeds of the first transfer electric motor 303A and the second transfer electric motor 303B so as to slow down the rotation speeds of the first pinch roll 301A and the second pinch roll 301B.
Further, the rolling mill control unit 552 controls to reduce the rotation speed of the rolling roll 351. More specifically, the rolling mill control unit 552 slows down the rotation of the rolling motor 354 so that the rolling mill speed becomes slower than the rolling mill speed which is the target value in the steady casting state, and the rolling roll 351 rotates. Controls to reduce the speed.
Further, the coiler control unit 553 controls to reduce the winding speed of the steel sheet 10 by the coiler. More specifically, the coiler control unit 553 reduces the rotation speed of the coiler motor 455 so that the coiler speed becomes slower than the coiler speed which is the target value in the steady casting state, and winds up the steel plate 10 by the coiler. Control to reduce the speed.
The first pinch roll speed, the second pinch roll speed, the rolling mill speed, and the coiler speed before deceleration are the same speeds, which are 80 (mpm) in the present embodiment.
The first pinch roll speed, the second pinch roll speed, the rolling mill speed, and the coiler speed after deceleration are the same speed, which is 5 (mpm) in the present embodiment.

In step S301, the rolling mill control unit 552 controls to release the rolling roll 351. More specifically, the rolling mill control unit 552 controls the rolling mill power cylinder 353 to increase the distance between the pair of rolling rolls 351 so that at least one rolling roll 351 is separated from the steel sheet 10. To stop the rolling of the steel sheet 10 by the rolling roll 351.
In step S302, the measured value acquisition unit 559 acquires the value of the current flowing from the first ammeter 306A to the first transfer motor 303A. The passage determination unit 557 determines whether or not the broken portion of the steel plate 10 has passed through the first pinch roll 301A based on the acquired change amount of the current flowing through the first transfer motor 303A. More specifically, the passage determination unit 557 determines that the broken portion of the steel plate 10 has passed through the first pinch roll 301A when the current differential value of the first transfer motor 303A is equal to or greater than the transfer threshold value.
When the pass determination unit 557 determines that the broken portion of the steel sheet 10 has passed through the first pinch roll 301A, the process proceeds to step S303, and in other cases, step S302 is executed again.

In step S303, the conveyor control unit 554 controls to open the first pinch roll 301A. More specifically, the transporter control unit 554 controls the first transporter power cylinder 302A to control the distance between the pair of first pinch rolls 301A to be wider than in the steady casting state.
In step S304, the transfer machine control unit 554 controls to stop the rotation of the first transfer motor 303A, stop the rotation of the first pinch roll 301A, and stop the transfer by the first transfer machine 300A.
In step S305, the conveyor control unit 554 determines whether or not the hunting convergence time has elapsed since the broken portion of the steel plate 10 passed through the first pinch roll 301A. The carrier control unit 554 advances the process to step S306 when the hunting convergence time has elapsed, and executes step S305 again when the hunting convergence time has not elapsed.

In step S306, the measured value acquisition unit 559 acquires the value of the current flowing from the second ammeter 306B to the second transfer motor 303B. The passage determination unit 557 determines whether or not the broken portion of the steel plate 10 has passed through the second pinch roll 301B based on the acquired change amount of the current flowing through the second transfer motor 303B. More specifically, the passage determination unit 557 determines that the broken portion of the steel plate 10 has passed through the second pinch roll 301B when the current differential value of the second transfer motor 303B is equal to or greater than the transfer threshold value.
When the pass determination unit 557 determines that the broken portion of the steel sheet 10 has passed through the second pinch roll 301B, the process proceeds to step S307, and in other cases, step S306 is executed again.

In step S307, the conveyor control unit 554 controls to open the second pinch roll 301B. More specifically, the transporter control unit 554 controls the second transporter power cylinder 302B to control the distance between the pair of second pinch rolls 301B to be wider than in the steady casting state.
In step S308, the transfer machine control unit 554 controls to stop the rotation of the second transfer motor 303B, stop the rotation of the second pinch roll 301B, and stop the transfer by the second transfer machine 300B. Further, the rolling mill control unit 552 controls to stop the rotation of the rolling motor 354 and stop the rotation of the rolling roll 351. Further, the coiler control unit 553 controls to stop the rotation of the coiler motor 455 and stop the winding of the steel plate 10.

Next, the second fracture control process will be described with reference to FIG. FIG. 18 is a flowchart of the second fracture control process.
In step S400, the transfer machine control unit 554 controls to stop the rotation of the first transfer motor 303A, stop the rotation of the first pinch roll 301A, and stop the transfer by the first transfer machine 300A. Further, the transport machine control unit 554 controls to stop the rotation of the second transport motor 303B, stop the rotation of the second pinch roll 301B, and stop the transport by the second transport machine 300B. Further, the rolling mill control unit 552 controls to stop the rotation of the rolling motor 354 and stop the rotation of the rolling roll 351. Further, the coiler control unit 553 controls to stop the rotation of the coiler motor 455 and stop the winding of the steel plate 10.
In step S401, the rolling mill control unit 552 controls to open the rolling roll 351 in the same manner as in step S301 of FIG.
In step S402, the conveyor control unit 554 controls to open the first pinch roll 301A in the same manner as in step S303 of FIG.
In step S403, the conveyor control unit 554 controls to open the second pinch roll 301B in the same manner as in step S307 of FIG.

Next, the rupture estimation control process will be described with reference to FIG. FIG. 19 is a flowchart of the fracture estimation time control process.
In step S500, the rolling mill control unit 552 controls the rolling mill 350 to lightly roll down the steel sheet 10. More specifically, the rolling mill control unit 552 controls the rolling mill power cylinder 353 to make the rolling mill pressing force weaker than in the steady casting state. In the present embodiment, the pressing force of the rolling mill, which is weaker than that in the steady casting state, is set to 1 (tonf).

In step S501, the rolling mill control unit 552 determines whether or not the false positive determination time has elapsed since the process of step S500 was performed. The false positive determination time represents the time from the fracture of the steel sheet 10 in at least one of the first intermediate region 602 and the second intermediate region 603 until the fractured portion of the steel plate 10 reaches the rear region 604. As the false positive determination time, it is possible to use a time equal to or longer than the time from when the steel sheet 10 reaches the first conveyor 300A to when it reaches the rolling mill 350. In the present embodiment, the false positive determination time is 1 (sec). When the steel plate is actually broken in the first intermediate region 602 or the second intermediate region 603, the fractured portion of the steel plate 10 reaches the rear region 604 by the time when the false detection determination time elapses, so that the fracture determination unit 555 Can determine that the fractured portion of the steel sheet 10 has reached the rear region 604, and the second fracture control process of FIG. 18 is executed.
The rolling mill control unit 552 advances the process to step S502 when the false positive determination time has elapsed, and executes step S501 again when the false detection determination time has not elapsed.

If the estimation unit 556 estimates the fracture of the steel plate 10 in step S114 or step S115 of FIG. 14 and the estimation is correct and the steel plate 10 actually fractures, the process does not proceed from step S501 to step S502. The fracture estimation control process of 19 is completed. This point will be described below.
As described with reference to FIG. 14, after step S102, the processes of step S103, step S108, and step S113 start in parallel. Therefore, when the estimation unit 556 estimates the fracture of the steel plate 10 in step S114 or step S115 ahead of the process of step S113, step S501 and step S108 ahead of the process of step S114 and step S115 are parallel to each other. Works on.
Here, consider a case where the estimation of step S114 or step S115 in FIG. 14 is correct and the steel plate 10 actually breaks. In this case, in the failure estimation time control process of FIG. 19, the process does not proceed from step S501 during the false positive determination time. Then, during the false positive determination time, the broken portion of the steel sheet 10 reaches the rear region 604. Therefore, in step S108 operating in parallel with step S501, the fracture determination unit 555 determines that the steel plate 10 has a fracture portion in the rear region 604, and the casting machine stop control process in step S110 and the second step S111. After the fracture control process is completed, the casting and rolling control process of FIG. 14 is completed. The fracture estimation control process of FIG. 19 is a process included in the casting / rolling control process of FIG. 14, and the fracture estimation control process of FIG. 19 ends when the casting / rolling control process of FIG. 14 ends.
Therefore, if the estimation unit 556 estimates the fracture of the steel plate 10 in step S114 or S115 of FIG. 14 and the estimation is correct and the steel plate 10 actually fractures, the process does not proceed from step S501 to step S502. , The fracture estimation control process of FIG. 19 is completed.

In step S502, the rolling mill control unit 552 controls the rolling mill 350 so that it is in the state of the rolling mill 350 in the steady casting state. More specifically, the rolling mill control unit 552 controls the rolling mill 350 so as to satisfy the rolling target. Therefore, in step S502, the state in which the rolling mill 350 lightly presses the steel sheet 10 is released, and the rolling mill pressing force returns to the state before step S500.

[First operation example]
Next, a first operation example of the control system 1 will be described with reference to FIGS. 20 to 24.
The first operation example is an operation example of the control system 1 in the steady casting state until the time 20 (sec), and when the steel plate 10 breaks in the front region 601 at the time 20 (sec). At time 20 (sec), the fracture determination unit 555 determines in step S103 of FIG. 14 that the steel plate 10 has fractured in the front region 601.
First, the state change of the double-roll type continuous casting machine 150 in the first operation example will be described with reference to FIGS. 20 (a) and 20 (b). FIG. 20A is a diagram showing a casting roll speed graph showing a time change of the casting roll speed in the first operation example. FIG. 20B is a diagram showing a casting roll gap showing a time change in the size of the casting roll gap in the first operation example.
As shown in FIG. 20 (a), at time 20 (sec), in the process of FIG. 15, the casting roll speed starts to decrease, and the casting roll speed changes from 80 (mpm) to 5 (mpm). Further, after 1 (sec), which is the discharge time, elapses, the casting roll speed starts to decrease again, and the casting roll speed becomes 0 (mpm). Further, as shown in FIG. 20 (b), the casting rolls are opened and the distance between the pair of casting rolls 201 is expanded to 50 (mm).

Next, the state change of the first conveyor 300A in the first operation example will be described with reference to FIGS. 21 (a) and 21 (b). FIG. 21A is a diagram showing a first pinch roll speed graph showing a time change of the first pinch roll speed in the first operation example. FIG. 21B is a diagram showing a first pinch roll gap graph showing a time change of the first pinch roll gap in the first operation example.
As shown in FIG. 21 (a), by the process of FIG. 17, at time 20 (sec), the first pinch roll speed starts to decrease and the first pinch roll speed changes from 80 (mpm) to 5 (mpm). ..
Further, in the first operation example, the broken portion of the steel plate 10 passes through the first pinch roll 301A at time 22 (sec) 2 (sec) after the steel plate 10 is broken in the front region 601. In step S302 of FIG. 17, the passage determination unit 557 determines that the broken portion of the steel plate 10 has passed through the first pinch roll 301A at time 22 (sec).
At time 22 (sec), as shown in FIG. 21 (a), by the process of FIG. 17, the first pinch roll speed starts to decrease and the first pinch roll speed becomes 0 (mpm). Further, the first pinch roll 301A is opened, and the distance between the pair of first pinch rolls 301A is expanded to 50 (mm).

Next, the state change of the second conveyor 300B in the first operation example will be described with reference to FIGS. 22 (a) and 22 (b). FIG. 22A is a diagram showing a second pinch roll speed graph showing a time change of the second pinch roll speed in the first operation example. FIG. 22B is a diagram showing a second pinch roll gap graph showing a time change of the second pinch roll gap in the first operation example.
As shown in FIG. 21 (a), by the process of FIG. 17, at time 20 (sec), the second pinch roll speed starts to decrease, and the second pinch roll speed changes from 80 (mpm) to 5 (mpm).
Further, in the first operation example, the broken portion of the steel plate 10 passes through the second pinch roll 301B at time 23 (sec) 3 (sec) after the steel plate 10 is broken in the front region 601. In step S306 of FIG. 17, the passage determination unit 557 determines that the broken portion of the steel plate 10 has passed through the second pinch roll 301B at time 23 (sec).
At time 23 (sec), by the process of FIG. 17, as shown in FIG. 22 (a), the second pinch roll speed starts to decrease again, and the second pinch roll speed becomes 0 (mpm). Further, as shown in FIG. 22B, the second pinch roll 301B is opened, and the distance between the pair of second pinch rolls 301B is expanded to 50 (mm).

Next, the state change of the rolling mill 350 in the first operation example will be described with reference to FIGS. 23 (a), (b), and (c). FIG. 23A is a diagram showing a rolling mill speed graph showing a time change of the rolling mill speed in the first operation example. FIG. 23B is a diagram showing a rolling roll gap graph showing a time change of the rolling roll gap in the first operation example. FIG. 23C is a diagram showing a rolling mill pressing force graph showing a time change of the rolling mill pressing force in the first operation example.
As shown in FIG. 23 (a), by the process of FIG. 17, at time 20 (sec), the rolling mill speed starts to decrease and the rolling mill speed changes from 80 (mpm) to 5 (mpm). Then, when the broken portion of the steel sheet 10 passes through the second pinch roll 301B at time 23 (sec), the rolling mill speed starts to decrease again and the rolling mill speed becomes 0 (mpm). Further, as shown in FIG. 23 (b), by the process of FIG. 17, the rolling rolls 351 are released at time 20 (sec), and the distance between the pair of rolling rolls 351 is expanded to 50 (mm). Further, as shown in FIG. 23 (c), at time 20 (sec), the distance between the pair of rolling rolls 351 begins to increase and the rolling mill 350 does not roll the steel sheet 10, so that at time 20 (sec). When the rolling mill pressing force drops from 200 (tonf) to 0 (tonf).

Next, the state change of the coiler 450 in the first operation example will be described with reference to FIG. 24. FIG. 24 is a diagram showing a coiler speed graph showing a time change of the coiler speed in the first operation example.
As shown in FIG. 24, by the process of FIG. 17, at time 20 (sec), the coiler speed starts to decrease and the coiler speed changes from 80 (mpm) to 5 (mpm). Then, when the broken portion of the steel plate 10 passes through the second pinch roll 301B at time 23 (sec), the coiler speed starts to decrease again and the coiler speed becomes 0 (mpm).

[Second operation example]
Next, a second operation example of the control system 1 will be described with reference to FIGS. 25 to 28.
In the second operation example, the control system 1 is in a steady casting state until time 20 (sec), and at time 20 (sec), the steel plate 10 breaks in the rear region 604 and the elevating roll 401 falls. This is an operation example. At time 20 (sec), the fracture determination unit 555 determines in step S108 of FIG. 14 that the fractured portion of the steel plate 10 is in the rear region 604.
The state change of the double-roll type continuous casting machine 150 in the second operation example is the same as the state change of the double-roll type continuous casting machine 150 in the first operation example described with reference to FIGS. 20 (a) and 20 (b). The same is true.

Next, the state change of the first conveyor 300A in the second operation example will be described with reference to FIGS. 25 (a) and 25 (b). FIG. 25A is a diagram showing a first pinch roll speed graph showing a time change of the first pinch roll speed in the second operation example. FIG. 25B is a diagram showing a first pinch roll gap graph showing a time change of the first pinch roll gap in the first operation example.
At time 20 (sec), as shown in FIG. 25 (a), by the process of FIG. 18, the first pinch roll speed starts to decrease and the first pinch roll speed changes from 80 (mpm) to 0 (mpm). .. Further, as shown in FIG. 25 (b), the first pinch roll 301A is opened, and the distance between the pair of first pinch rolls 301A is expanded to 50 (mm).

Next, the state change of the second conveyor 300B in the second operation example will be described with reference to FIGS. 26 (a) and 26 (b). FIG. 26A is a diagram showing a second pinch roll speed graph showing a time change of the second pinch roll speed in the second operation example. FIG. 26B is a diagram showing a second pinch roll gap graph showing a time change of the second pinch roll gap in the second operation example.
At time 20 (sec), as shown in FIG. 26 (a), the process of FIG. 18 starts to decrease the second pinch roll speed, and the second pinch roll speed changes from 80 (mpm) to 0 (mpm). .. Further, as shown in FIG. 26 (b), the process of FIG. 18 opens the second pinch roll 301B, and the distance between the pair of second pinch rolls 301B is expanded to 50 (mm).

Next, the state change of the rolling mill 350 in the second operation example will be described with reference to FIGS. 27 (a), 27 (b), and (c). FIG. 27A is a diagram showing a rolling mill speed graph showing a time change of the rolling mill speed in the second operation example. FIG. 27B is a diagram showing a rolling roll gap graph showing a time change of the rolling roll gap in the second operation example. FIG. 27C is a diagram showing a rolling mill pressing force graph showing a time change of the rolling mill pressing force in the second operation example.
As shown in FIG. 27 (a), by the process of FIG. 18, at time 20 (sec), the rolling mill speed starts to decrease and the rolling mill speed changes from 80 (mpm) to 0 (mpm). Further, as shown in FIG. 27 (b), by the process of FIG. 18, at time 20 (sec), the rolling rolls 351 are opened and the distance between the pair of rolling rolls 351 is expanded to 50 (mm). .. Further, as shown in FIG. 27 (c), at time 20 (sec), the distance between the pair of rolling rolls 351 begins to increase and the rolling mill 350 does not roll the steel sheet 10, so that at time 20 (sec). When the rolling mill pressing force drops from 200 (tonf) to 0 (tonf).

Next, the state change of the coiler 450 in the second operation example will be described with reference to FIG. 28. FIG. 28 is a diagram showing a coiler speed graph showing a time change of the coiler speed in the second operation example.
As shown in FIG. 28, by the process of FIG. 18, at time 20 (sec), the coiler speed starts to decrease and the coiler speed changes from 80 (mpm) to 0 (mpm).

[Third operation example]
Next, a third operation example of the control system 1 will be described.
The third operation example is a steady casting state until the time 19.5 (sec), and at the time 19.5 (sec), the operation example of the control system 1 when the steel plate 10 breaks in the second intermediate region 603. Is. At time 19.5 (sec), the estimation unit 556 estimates that the steel plate 10 broke in the region between the first conveyor 300A and the rolling mill 350 in step S115 of FIG.
With reference to FIG. 29, the state change of the rolling mill 350 in the third operation example will be described. FIG. 29 is a diagram showing a rolling mill pressing force graph showing a time change of the rolling mill pressing force in the third operation example.
As shown in FIG. 29, by the process of step S500 of FIG. 19, at time 19.5 (sec), the rolling mill pressing force starts to decrease and weakens from 200 (tonf) to 1 (tonf), and the rolling mill 350. Is in a state of lightly rolling the steel plate 10.

Further, the third operation example is an operation example in which the broken portion of the steel sheet 10 passes through the rolling mill 350 and reaches the rear region 604 at time 20 (sec). Therefore, the state of the control system 1 after the time 20 (sec) is the same as that of the second operation example described with reference to FIGS. 25 to 28.

In the third operation example, step S500 in FIG. 19 is executed, but step S502 in FIG. 19 is not executed. This is because the processing is performed as follows.
First, when the time is 19.5 (sec), step S500 in FIG. 19 is executed as described above. After that, in the process of FIG. 19, step S501 is executed until the false positive determination time of 1 (sec) elapses and the time reaches 20.5 (sec).
On the other hand, at time 20 (sec), in step S108 of FIG. 14, the fracture determination unit 555 determines that there is a fracture portion in the rear region 604, which is the region between the rolling mill 350 and the coiler 450, and FIG. The casting machine stop process of FIG. 18 and the second fracture control process of FIG. 18 are executed, and then the casting and rolling control process of FIG. 14 ends.
Therefore, in the third operation example, the casting / rolling control process of FIG. 14 is completed before the step S501 of FIG. 19 is executed, so that the step S501 of FIG. 19, which is a process in the casting / rolling control process, is not executed. ..
Even when the steel plate 10 breaks in the first intermediate region 602, the control system 1 operates in the same manner as in the third operation example.

[Fourth operation example]
Next, a fourth operation example of the control system 1 will be described.
The fourth operation example is an operation example of the control system 1 when the estimation unit 556 mistakenly estimates that the steel plate 10 is broken in the second intermediate region 603 at time 20 (sec). In the fourth operation example, the steel plate 10 is not actually broken.
The operation of the casting and rolling equipment 100 other than the rolling mill 350 in the fourth operation example is the operation in the steady casting state.

With reference to FIG. 30, the state change of the rolling mill 350 in the fourth operation example will be described. FIG. 30 is a diagram showing a rolling mill pressing force graph showing a time change of the rolling mill pressing force in the fourth operation example.
As shown in FIG. 30, by the process of step S500 of FIG. 19, at time 20 (sec), the rolling mill pressing force starts to decrease and weakens from 200 (tonf) to 1 (tonf), and the rolling mill 350 becomes a steel plate. It is in a state of lightly rolling down 10. Further, after the erroneous detection determination time of 1 (sec) has elapsed, as shown in FIG. 30, the state in which the rolling mill 350 lightly presses the steel plate 10 is released, and the rolling mill is pressed in the steady casting state. It returns to the power of 200 (tonf).
In the fourth operation example, unlike the case of the third operation example, the steel plate 10 is not actually broken. Therefore, the fracture determination unit 555 does not determine that there is a fracture portion in the rear region 604, which is the region between the rolling mill 350 and the coiler 450, and the casting and rolling control process of FIG. 14 is not completed. Therefore, after the erroneous detection determination time elapses, step S502 in FIG. 19 is executed, and the rolling mill pressing force returns to 200 (tonf).

[effect]
As described above, the control device 500 controls to stop the rotation of the pair of casting rolls 201 after the discharge time has elapsed when the steel plate 10 breaks in the front region 601. Therefore, even if the steel plate 10 is broken, the casting roll 201 is stopped after the hot water pool 210 is emptied, so that the molten steel 11 does not solidify in the hot water pool 210. Therefore, the work of peeling the steel material adhered to the casting roll 201 from the casting roll 201 becomes unnecessary. Therefore, it is possible to prevent the life of the casting roll 201 from being shortened due to scraping of the surface dimples of the casting roll due to the work of peeling the steel material from the casting roll 201, and it is possible to protect the twin roll type continuous casting machine 150. Further, the complexity of maintenance work can be reduced. As described above, in the control system 1, when the steel sheet is broken, the double-roll type continuous casting machine can be appropriately stopped.
Further, the control device 500 determines that the steel plate 10 is broken in the front region 601 when the steel plate 10 reaches the first reference height below the casting roll gap of the double roll type continuous casting machine 150. Therefore, the control device 500 can accurately determine the breakage of the steel plate 10.

Further, the control device 500 determines that the steel plate 10 is broken in the front region 601 when the state in which the steel plate 10 reaches the first reference height continues during the first reference time. Therefore, the risk of erroneous determination is reduced.

Further, the control device 500 controls the stopper 162 to close the spout of the tundish 161 when it is determined that the steel plate 10 is broken in the front region 601. Therefore, when the steel plate 10 breaks in the front region 601 the injection of the molten steel 11 into the puddle 210 is stopped, and the puddle 210 can be emptied.

Further, the control device 500 determines that there is a broken portion of the steel plate 10 in the rear region 604 when the vertical position of the elevating roll 401 is equal to or less than the second reference height. Therefore, the breakage of the steel plate 10 can be accurately detected without a time lag without using a measuring instrument such as a tension detector which may be damaged by the heat of the steel plate 10. Further, when the control device 500 determines that there is a broken portion of the steel plate 10 in the rear region 604, the control device 500 controls to stop the rotation of the rolling roll 351 and stop the discharge of the steel plate 10 by the rolling mill 350. Further, the control device 500 controls to stop the rotation of the coiler motor 455 and stop the pulling of the steel plate 10 by the coiler 450. Therefore, when there is a broken portion of the steel plate 10 in the rear region 604, the transportation of the steel plate 10 can be stopped quickly.

Further, the control device 500 determines that the steel plate 10 has a broken portion in the rear region 604 when the vertical position of the elevating roll 401 is equal to or less than the second reference height during the second reference time. Therefore, the risk of erroneous determination is reduced.

Further, the control device 500 controls to stop the rotation of the pair of casting rolls 201 after the discharge time has elapsed when it is determined that the steel plate 10 has a broken portion in the rear region 604. Therefore, since the casting roll 201 is stopped after the puddle 210 is emptied, the molten steel 11 does not solidify in the puddle 210.

Further, when the control device 500 determines that the steel plate 10 is broken in the front region 601 or determines that the steel plate 10 has a broken portion in the rear region 604, at least one of the rolling rolls 351 is separated from the steel plate 10. As described above, the control for increasing the distance between the pair of rolling rolls 351 is performed. Therefore, when the transportation of the steel sheet 10 is stopped, maintenance work such as taking out the steel sheet 10 from the casting and rolling equipment 100 becomes easy.

Further, the control device 500 is a region between the first conveyor 300A and the rolling mill 350 based on the amount of change in the current flowing through the first transfer motor 303A or the amount of change in the current flowing through the second transfer motor 303B. It is estimated whether or not the steel plate 10 is broken. Then, when the steel plate 10 is estimated to be broken, the control device 500 weakens the rolling mill pressing force from the estimation that the steel plate 10 is broken until the erroneous detection determination time elapses. Therefore, even if the steel plate 10 is actually broken and the broken portion of the steel plate 10 passes through the rolling rolls 351 and comes into contact with the pair of rolling rolls 351 but the rolling mill pressing force is weakened. As described with reference to FIG. 2, the risk of damage to the rolling mill 350 is reduced.
Further, when the broken portion of the steel plate 10 passes through the rolling roll 351 and immediately after passing, the control device 500 determines that the broken portion of the steel plate 10 is in the rear region 604 based on the looper height 41, and the rolling roll. Open 351. Therefore, the contact of the pair of rolling rolls 351 can be avoided, and even if the pair of rolling rolls 351 come into contact with each other, the contact time can be shortened. Therefore, the risk of damage to the rolling mill 350 is reduced.

Further, the control device 500 controls to return the rolling mill pressing force of the rolling mill 350 after the false detection determination time has elapsed. Therefore, when the control device 500 presumes that the steel sheet 10 is erroneously broken, the control system 1 can continue the steady casting state, and can continue the casting and rolling of the steel sheet 10.
Further, the control device 500 weakens the pressing force of the rolling mill until the false detection determination time elapses, but does not open the rolling roll 351. Therefore, the state in which the rolling roll 351 is in contact with the steel sheet 10 is continued. Therefore, when the control device 500 mistakenly estimates that the steel sheet 10 is broken, even if the rolling mill pressing force of the rolling mill 350 is returned, the rolling roll 351 once separated from the steel plate 10 comes into contact with the steel sheet 10 again, and the steel sheet It is possible to prevent the movement of the 10 from being disturbed and causing an unstable state such as the heated steel plate 10 coming into contact with each device.

Further, when the control device 500 determines that the steel plate 10 is broken in the front region 601 and determines that the broken portion of the steel plate 10 has passed through the first conveyor 300A, the control device 500 is controlled to stop the transportation by the first conveyor 300A. I do. Further, the control device 500 determines that the broken portion of the steel plate 10 has passed through the first conveyor 300A, and after the hunting convergence time has elapsed, the broken portion of the steel plate 10 has passed through the second conveyor 300B. When the determination is made, the control for stopping the transfer by the second transfer machine 300B is performed. Here, the movement of the steel plate 10 is unstable until the hunting convergence time elapses, and the control device 500 may mistakenly determine that the broken portion of the steel plate 10 has passed through the second conveyor 300B. .. However, the control device 500 controls to stop the transfer by the second transfer machine 300B based on the pass determination of the broken portion after the hunting convergence time has elapsed. Therefore, the possibility that the control device 500 mistakenly determines that the broken portion of the steel plate 10 has passed through the second conveyor 300B is reduced.

Further, when the control device 500 determines that the steel plate 10 is broken in the front region 601 and the broken portion has passed through the second conveyor 300B, the control device 500 stops the rotation of the rolling roll 351 and causes the steel plate 10 to break. Control is performed to stop the discharge, and further, control is performed to stop the winding of the steel plate 10 by the coiler 450 and stop the drawing of the steel plate 10. Therefore, the control device 500 does not stop the rotation of the rolling roll 351 and does not stop the winding of the steel sheet 10 by the coiler 450 until it is determined that the broken portion of the steel sheet 10 has passed through the second conveyor 300B. .. Therefore, even if the steel plate 10 is broken, the coiler 450 can sufficiently wind the steel plate 10.

Further, when the control device 500 determines that the steel plate 10 is broken in the front region 601, the control device 500 slows down the casting roll speed, the pinch roll speed, the rolling mill speed, and the coiler speed. Therefore, the possibility that the broken steel plate 10 will move unstable is reduced, and the safety of the casting and rolling equipment 100 is ensured.

[Other embodiments]
The casting and rolling equipment 100 includes one rolling mill 350, but there may be a plurality of rolling mills 350. For example, a plurality of the rolling mills may be arranged between the second transporter 300B and the looper 400 in the transport path of the steel sheet 10. At this time, the second transporter 300B transports the steel sheet 10 to the rolling mill 350 closest to the double-roll type continuous casting machine 150 in the transport path of the steel sheet 10. The rolling mill 350 closest to the looper 400 in the transport path of the steel sheet 10 discharges the steel sheet 10 to the looper 400. As a result, using a plurality of rolling mills 350, the accuracy of rolling can be improved and the steel sheet 10 can be rolled so as to be thinner than in the case of one rolling mill 350.
Similar to steps S114 and S115 in FIG. 14, the control device 500 estimates whether or not the steel plate 10 is broken in the region between the adjacent rolling mills 350 based on the amount of change in the current flowing through the rolling mill 354. do. When it is estimated that the steel plate 10 is broken in the region between the adjacent rolling mills 350, the control device 500 executes the breaking estimation control process of FIG. The rolling mill pressing force of the rolling mill 350 is weakened by the rupture estimation control process. Therefore, even if the steel plate 10 is actually broken and the broken portion of the steel plate 10 passes through the rolling rolls 351 and comes into contact with the pair of rolling rolls 351 but the rolling mill pressing force is weakened. As described with reference to FIG. 2, the risk of damage to the rolling mill 350 is reduced.

The casting and rolling equipment 100 includes two conveyors 300, but the conveyor 300 may be one or three or more.
Although the present invention has been described above with the embodiments, the above embodiments are merely examples of embodiment of the present invention, and the technical scope of the present invention is limitedly interpreted by these. It shouldn't be. That is, the present invention can be implemented in various forms without departing from the technical idea or its main features.

1 Control system, 100 casting and rolling equipment, 150 double-roll continuous casting machine, 300 conveyor, 350 rolling machine, 400 looper, 450 coiler, 500 control device

Claims (9)

A looper provided with an elevating roll arranged in a transport path of a steel plate and pressing the steel plate from above to generate tension, and a counter balance weight for adjusting the force with which the elevating roll presses the steel plate.
A discharge device arranged in the transport path of the steel plate and discharging the steel plate to the looper.
A pull-in device that pulls in the steel plate discharged from the looper, and
When the vertical position of the elevating roll is equal to or less than the roll reference height, it is determined that there is a broken portion which is an end portion of the broken steel plate in the determination region which is the region between the discharging device and the pulling device. A determination system including a break determination means. The break determination means determines that the break portion is in the determination region when the vertical position of the elevating roll continues to be equal to or lower than the roll reference height for a preset reference time. The determination system according to claim 1, wherein the determination system is characterized by the above. When the fracture determination means determines that the fractured portion is present in the determination region, the first control means for controlling the ejection of the steel sheet by the ejection device and the first control means.
The claim is further provided with a second control means for controlling the pulling of the steel sheet by the pulling device when it is determined by the breaking determining means that the broken portion is present in the determination region. The determination system according to 1 or 2. The discharge device is a rolling machine that rolls the steel sheet with a pair of rolling rolls so as to satisfy a preset rolling target.
When the breaking determination means determines that the breaking portion is in the determination region, the first control means stops the rotation of the rolling roll to stop the ejection of the steel sheet, and at least one of the above. The determination system according to claim 3, wherein the control is performed to increase the distance between the pair of the rolling rolls so that the rolling rolls are separated from the steel sheet. The determination system according to claim 4, wherein a plurality of the rolling mills are arranged in the transport path of the steel sheet. The pull-in device is a coiler that winds up the steel plate discharged from the looper.
The second control means controls to stop the winding of the steel sheet by the coiler and stop the pulling of the steel sheet when the break determination means determines that the break portion is in the determination region. The determination system according to any one of claims 3 to 5, wherein the determination system is characterized. A looper provided with an elevating roll arranged in a transport path of a steel plate and pressing the steel plate from above to generate tension, and a counter balance weight for adjusting the force with which the elevating roll presses the steel plate.
A discharge device arranged in the transport path of the steel plate and discharging the steel plate to the looper.
A determination device used in equipment equipped with a pull-in device for pulling in the steel plate discharged from the looper.
When the vertical position of the elevating roll is equal to or less than the roll reference height, it is determined that there is a broken portion which is an end portion of the broken steel plate in the determination region which is the region between the discharging device and the pulling device. A determination device including a break determination means. A looper provided with an elevating roll arranged in a transport path of a steel plate and pressing the steel plate from above to generate tension, and a counter balance weight for adjusting the force with which the elevating roll presses the steel plate.
A discharge device arranged in the transport path of the steel plate and discharging the steel plate to the looper.
It is a control method of a determination device used in a facility including a pull-in device for pulling in the steel plate discharged from the looper.
When the vertical position of the elevating roll is equal to or less than the roll reference height, it is determined that there is a broken portion which is an end portion of the broken steel plate in the determination region which is the region between the discharging device and the pulling device. A method for controlling a determination device, which comprises a fracture determination step. A program for operating a computer as the determination device according to claim 7.

Images