JP2008272820A - Cutting device and method for continuously cast material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas type cutting device in continuous casting equipment where the gas torch movement part is manually retreated to the outside of the line, and the operation is continued, when the generation of abnormality regarding the movement of each gas torch movement part. <P>SOLUTION: The cutting device for a continuously cast material is provided with: a plurality of inverter devices for controlling-driving a plurality of gas torch movement units, respectively, each provided with a vector control system control unit and a V/f control system control unit working alternatively; and a controller controlling the plurality of gas torch movement units and the plurality of inverter devices and controlling a cutting operation for a continuously cast material. The controller works the vector control system control unit, so as to move each gas torch movement unit upon an ordinary cutting operation, and changes the same into the V/f control system control unit and works the same, so as to retreat the gas torch movement unit from the surface of the continuously cast material and practices a cutting operation by the other gas torch movement unit when the generation of abnormality regarding the movement of each gas torch movement unit is detected by a speed detector. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gas-type cutting device for continuously cast material cast by a continuous casting facility, and in particular, even when an abnormality occurs in the movement of the gas torch of the gas-type cutting device, the cutting operation of the continuous cast material is completed without interruption. It is about technology.

  In the continuous casting equipment of the steel industry, molten steel is continuously cooled and solidified to produce continuous cast material. The continuous casting material 2 is moved by the transport roll 4. In order to cut the continuous cast material 2, a gas type cutting device 1 as schematically shown in FIGS. 1 and 2 is often used. When the continuous casting material 2 reaches a desired length, the gas-type cutting device 1 presses and fixes the carriage 1a to the continuous casting material 2 with the clamp device 1b, and the continuous cutting material 2 on the transport roll 4 is fixed. While interlocking with the movement, the pair of (two) gas torches 1c on the moving portion 1j provided on the carriage 1a is orthogonal to the moving direction of the continuous cast material 2, that is, a continuous cast material (hereinafter referred to as a cast material). 2), the continuous cast material 2 is cut and separated into slabs 3.

  FIG. 2 is a front view of an example of the gas cutting device 1 viewed from the conveyance direction (production line direction) of the continuous cast material 2. The moving part 1j is provided with an end face detector 1d having a lifting function. When the continuous cast material 2 is cut, the end face detector 1d is lowered toward the continuous cast material 2. Then, the width is adjusted at a high speed to detect the position of the end face of the continuous cast material 2.

  When the end face position of the continuous cast material 2 is detected, the gas torch 1c temporarily stops its movement, and after the end face detector 1d is lifted, each gas torch 1c is moved again to the center of the continuous cast material 2 while being cut. Through the cutting process, the cutting of the continuous cast material 2 is completed. The operation of the end face detector 1d and the gas torch 1c is shown in FIG.

  Conventionally, as disclosed in Patent Document 1, the movement control of the blower tube (corresponding to the gas torch in the present application) of the cutting device has a fast feed control at the time of detecting the end face as described above in order to speed up the cutting operation. A two-stage configuration with low speed control at the time of cutting was used, and a composite servo motor or the like having a two-stage speed control region was used, but in order to use it stably, a clutch plate between the composite servo motors It was necessary to devise a method to detect slippage of the brake friction plate.

Therefore, as shown in FIG. 4, in recent years, instead of using a plurality of motors, the gas torch moving unit 1j has a wide speed control area and a speed by a vector control method that is excellent in speed accuracy in a low speed area. A controllable inverter controller (not shown) drives one induction motor 1f directly connected to a speed detector 1g for detecting rotation, rotates a pinion 1h (small gear), and is attached to a carriage 1a. The structure which moves via the rack 1i (straight tooth) is common.
JP 2000-249608 A

  Since the gas-type cutting device 1 during cutting moves in synchronism with the continuous casting material 2 as described above, vibration of the continuous casting material during casting is directly transmitted to the carriage 1a, and the continuous casting material 2 is heated to red and hot. In an environment exposed to heat from Therefore, the incidence rate regarding the gas-type cutting device 1 is high among equipment troubles of the continuous casting equipment.

  In the gas torch moving part 1j, the speed detector 1g is particularly vulnerable to vibration and heat. From the speed detector 1g due to troubles such as a failure of the speed detector 1g or burnt wiring during the continuous casting 2 cutting. When a signal continuity failure to the inverter control device 8 occurs, in the vector control method using the speed measured by the speed detector 1g as a feedback value for internal calculation, the control becomes abnormal, so that the gas torch 1c Stop immediately. Since the pair of gas torches 1c are on the same moving rack 1i on the carriage 1a, in order to continue the operation by cutting the continuous cast material 2, the gas torch 1c stopped on the continuous cast material 2 is lined up. It will be necessary to evacuate outside. Therefore, the operator goes up to the carriage 1a and is exposed to the heat from the continuous casting material 2 while removing the pinion 1h (small gear) of the gas torch moving part 1j from the moving rack 1i and manually retracting it out of the casting line. There has occurred. In addition, if time is required for the evacuation work, the casting speed of the operation may be reduced, or in the worst case, the casting speed may be reduced to zero and the operation may be stopped. Moreover, the movement of the gas torch moving part 1j on the continuous cast material 2 may be difficult due to causes other than the speed detector 1g. As described above, once an abnormality such as the speed detector 1g occurs, it places a heavy burden on the operator and leads to an inhibition of production and a reduction in efficiency of casting equipment.

  The present invention solves the conventional problems as described above, even when the output value of the speed detector of the induction motor of the gas torch moving unit becomes abnormal, without placing a heavy burden on the operator, An object of the present invention is to provide a gas type cutting apparatus that can continuously cut a continuous cast material and continue the continuous casting operation without delay.

  The gas cutting device of the present invention comprises a cart that is movable in a continuous casting material moving direction, which is the manufacturing line direction, and a gas torch that heats and cuts the continuous casting material in the continuous casting material production line. A plurality of gas torch moving parts movable on the carriage in the direction perpendicular to the production line; a plurality of induction motors provided in each of the plurality of gas torch moving parts; and a plurality of rotation speeds for detecting the rotation speed of the induction motors A continuous cast material cutting device having a speed detector, wherein the vector control method control unit and the V / f control method control unit operate alternatively for controlling and driving each of the plurality of gas torch moving units. A control device for controlling a cutting operation of a continuous cast material by controlling the plurality of inverter devices, the plurality of gas torch moving units, and the plurality of inverter devices. The control device operates the vector control method control unit during normal cutting operation to move the gas torch moving unit, and the abnormality of the movement of the gas torch moving unit is detected by any of the plurality of speed detectors. When the occurrence is detected, the gas torch moving part whose rotational speed has been detected by the speed detector is operated by switching to the V / f control method control part to retract the gas torch moving part from the continuous cast material. Then, a cutting operation by another gas torch moving unit is executed.

  Also, the gas type cutting device of the present invention is configured such that the control device controls the inverter device for each of the plurality of gas torch moving units, and operates / stops each gas torch moving unit based on a preset cutting schedule. By comparing the speed control unit that outputs the speed command value, the speed actual value based on the rotational speed detected by the speed detection unit, and the preset specified speed, the abnormality of the movement of the gas torch moving unit An anomaly detector that detects the occurrence and outputs an anomaly signal, and an overall control of the cutting operation. Based on the anomaly signal, the control of the induction motor of the inverter device of the gas torch moving part that caused the anomaly is vector controlled. And a cutting control unit that switches from the system control unit to the V / f control system control unit.

  The gas cutting method of the present invention is a gas cutting method for cutting a continuous cast material into a slab using the gas cutting device described above, and operates the vector control method control unit of the inverter device during normal cutting operation. And a step of moving the gas torch moving unit, and a step of switching to the V / f control system control unit of the inverter device when the occurrence of an abnormality related to the movement of the gas torch moving unit is detected by the speed detector; Further, the gas torch moving part is evacuated from the continuous cast material, and a cutting operation by another gas torch moving part is executed.

  In the present invention, even if some abnormality occurs in the movement state of any of the gas torch moving parts among the plurality of gas torch moving parts, it becomes possible to automatically cut the continuous cast material in the other gas torch moving parts, Work that places an excessive burden on the operating operator can be eliminated, and the cause of troubles that cause a reduction in casting speed due to the above-described work and a situation where the worst operation is stopped can be eliminated.

  DESCRIPTION OF EMBODIMENTS Embodiments for carrying out the present invention will be described in detail with reference to the drawings. In each figure, the same reference numerals are used to indicate the same parts, and the description is clarified to avoid duplication.

<First Embodiment>
FIG. 5 is a diagram showing an outline of the configuration of the cutting control system of the cutting device in the embodiment for carrying out the present invention, and FIG. 4 is a schematic diagram of the gas torch moving unit 1j. In the present embodiment, the cutting control system includes an induction motor 1f that drives the gas torch moving unit 1j, a speed detector 1g that is attached to the induction motor 1f and detects rotation, and a detection output of the speed detector 1g. The inverter device 8 is driven by controlling the rotation, and the control device 7 controls the inverter device 8 and other devices in the cutting device. In the present embodiment, there are two inverter devices 8 for each of the two gas torch moving parts 1j. Note that the present invention can also be applied when there are three or more pairs of the gas torch moving unit 1j and the inverter device 8. Each gas torch moving part 1j has an induction motor 1f and a speed detector 1g.

  The internal configurations and functions of the control device 7 and the inverter device 8 will be described with reference to FIG. The control device 7 includes a cutting control unit 7a that controls the entire cutting operation for cutting the continuous cast material 2 in the cutting device. Process for managing the continuous casting process = cutting schedule such as slab cutting length setting and cutting speed setting is input from an upper computer 9 such as a computer via an I / O unit 7e configured by a LAN board for network connection, for example. Is done. In addition, using the operation screen 10 constituted by a computer = display for the operation worker to perform operation and monitoring of the operation state, the operation worker can change from time to time via the I / O unit 7f equipped with a keyboard and a mouse. If the cutting schedule can be input and changed, a flexible operation can be realized.

  The cutting schedule input to the control device 7 is accumulated in a storage unit 7d configured by an HDD, a DVD-RAM, or a semiconductor memory (volatile or non-volatile) via the cutting overall control unit 7a. For each cutting of each slab, the set value of the cutting schedule of the slab is read out by the cutting control unit 7a and used to control the cutting length of the continuous cast material and the cutting speed of the gas torch moving unit 1j during cutting.

  From the control device 7 to the host computer 9, the actual cutting length value and the actual cutting speed value are output via the I / O unit 7 e for each slab cut from the continuous cast material 2. The actual value is displayed via the / O section 7f.

  The length measuring unit 7 h of the control device 7 is measured by a length measuring device 11 constituted by a length measuring pulse generator (PLG, not shown) installed on a dedicated length measuring roll (not shown) or the transport roll 4. Based on the measured value of the advance length, the advance length of the continuous cast material 2 is converted into the length from the cut surface of the continuous cast material 2 and output to the cutting control unit 7a. The length measuring detector may be a rotation angle detector (not shown) instead of the pulse generator.

  The cutting determination part 7i is being fixed to the outer side of the both ends of the continuous cast material 2 in the vicinity of the conveyance roll 4 separately from the gas torch moving part 1j (not shown). For example, the light transmission detector 12 composed of a light emitter and a light receiver monitors the separation of the continuous cast material 2 and the slab. When the light transmission detector 12 changes from the light-shielded state to the light-transmitted state during the cutting operation, the cutting determination unit. 7i has a function of determining that the cutting has been completed and outputting a cutting completion signal to the cutting control unit 7a.

  The cutting overall control unit 7a compares the cutting length setting value read from the storage unit 7d with the measured value of the length from the cutting surface input from the length measuring unit 7h, derives a difference, and the difference is preset. When the length reaches or below the specified length, a clamp command is output to the clamp controller 7g. In addition, when a cutting completion signal is input from the cutting determination unit 7i, the cutting overall control unit 7a outputs a clamp release command to the clamp control unit 7g. The clamp control unit 7g is responsible for pressing or releasing the clamp device 1b against the continuous casting material 2 in accordance with these commands from the cutting control unit 7a.

  The inverter device 8 that controls and drives the gas torch moving unit 1j switches between the vector control method control unit 8a and the V / f control method control unit 8b, which are controllers for driving the induction motor 1f, and these two control method units. A control method switching unit 8c and a changeover switch 8d. The inverter device 8 is provided in each of the plurality of gas torch moving units 1j, and each inverter device 8 includes a vector control method control unit 8a, a V / f control method control unit 8b, a control method switching unit 8c, and a changeover switch 8d. have. A speed control system switching signal is output from the cutting overall control section 7a of the control device 7 to the control system switching section 8c, and the selector switch 8d is switched. On the other hand, information on the speed control method currently used by the control method switching unit 8c is input from the control method switching unit 8c to the cutting overall control unit 7a. In addition, an operation / stop command and a speed command value are output from the speed control unit 7 b of the control device 7 to the inverter device 8. The operation / stop command and the speed command value are sent to the controller selected from the vector control method control unit 8a and the V / f control method control unit 8b through the changeover switch 8d controlled by the control method switching unit 8c. Is output.

  Regardless of whether the controller of the vector control system control unit 8a or the V / f control system control unit 8b is selected, the control output of the system control unit is an electrical output (specifically, voltage) via the semiconductor power supply unit 8e. Or the current) to drive the induction motor 1f. When the vector control system control unit 8a is selected as a controller, the rotational speed feedback value (actual value) of the speed detector 1g is converted into a speed feedback value by the speed conversion unit 8f, and the vector control system controller performs an internal calculation. Used for. When the V / f control method control unit 8b is selected as a controller, the speed feedback value is not used because it is not necessary for internal calculation. The speed feedback value is also input from the speed conversion unit 8f to the abnormality detection unit 7c of the control device 7, and the abnormality detection unit 7c monitors the value so that the movement state of the speed detector 1g and the gas torch moving unit is normal. / It has a function to detect an abnormal state and output a speed abnormality detection signal when an abnormality is detected. In addition, the structure which inputs the rotation speed feedback value of the speed detector 1g directly into the abnormality detection part 7c instead of a speed feedback value may be sufficient.

  In addition to the above, although not shown in FIG. 8, the cutting control unit 7 a has a function of controlling an actuator, an electromagnetic valve, and the like that perform forward and backward movement of the carriage 1 a, up and down of the end face detector 1 d, and gas flame pattern control. Yes.

(Vector control method)
During operation, the host control device 7 outputs a signal for selecting the vector control method as the speed control method to the inverter device 8. The vector control method includes a frequency command value obtained by converting the cutting speed command value with a host controller, an actual current value flowing through the induction motor measured by the inverter device, an actual rotational speed value measured by the speed detector 1g, and an inverter device in advance. Based on the simplified electric circuit model of the induction motor 1f set in 8, the excitation current component and the torque current component are independently calculated in the inverter device 8 and synthesized on the vector space to actually generate the induction motor 1f. This is a method of controlling the desired torque with high accuracy by calculating the primary current value to be passed through the motor. Therefore, it is known that the speed control region is wide and suitable for speed control of a gas torch moving device that requires speed accuracy in a low speed region.

  During operation of the continuous casting facility, when the length of the continuous casting material 2 reaches a preset cutting set length, the carriage 1a is clamped to the continuous casting material 2 by the command of the clamp control 7g of the control device 7. Then, the cutting control unit 7a and the speed control unit 7b of the control device 7 output to the inverter device 8 speed command values corresponding to the end face detection, cutting, and cutting processes together with the operation commands. . The inverter device 8 controls the speed of the induction motor 1f using the actual speed value obtained by converting the signal from the speed detector 1g into the speed feedback value by the speed converter 8f according to the command.

  Processing for detecting an abnormality in the actual speed value will be described. FIG. 6 shows a flowchart of the abnormality determination logic of the speed detector 1g by the abnormality detector 7c. The actual speed value detected by the speed detector 1 g is converted from a rotation value to a speed by the speed conversion unit 8 f in the inverter device 8 and then input to the upper control device 7. The abnormality detection unit 7c in the control device first determines whether or not an operation command is being output to the inverter device (S100). If the operation command is being output, the first actual speed value is set in advance. It is determined whether or not the specified speed α1 is below the predetermined speed α1 (S101). On the other hand, during the stop command output, it is determined whether or not the actual speed exceeds a preset second specified speed α2 (S102). An abnormality of the speed detector 1g is determined based on the determination result, and when it is determined to be abnormal, a speed abnormality detection signal is output (S103), thereby constantly monitoring the speed feedback value from the speed detector 1g. In addition, each regulation speed (alpha) 1 and (alpha) 2 are preset based on the driving | running condition of a continuous casting installation.

  Next, FIG. 7 is a flowchart of the control device 7 when an abnormality of the speed detector 1g is detected by the abnormality detection unit 7c while the continuous cast material 2 is being cut. The cutting overall control unit 7a of the control device 7 stores the clamp command output to the clamp control unit 7g for each slab based on the speed abnormality detection signal in the storage unit 7d as a continuous cast material cutting signal. When the slab cutting completion signal based on the detection signal of the light transmission detector is input from the cutting determination unit 7i to the cutting overall control unit 7a when the slab cutting is completed during cutting, the continuous cast material cutting in-process signal is Erase from storage. Thus, whether or not the continuous cast material 2 is being cut is determined based on whether or not the continuous casting material cutting signal is present in the storage unit 7d (S200). If cutting is in progress, the normality or abnormality of the speed detector 1g is determined by the abnormality determination logic of the speed detector 1g using the processing flow of S100 to S103 (S201). And when abnormality is detected, the stop command is output with respect to the speed control part 7b, and the movement of the width direction of a gas torch is stopped (S202). On the other hand, the gas of the gas torch 1c or the cutting flame is squeezed to make a pilot flame (low flame), and the solenoid valve for gas supply is controlled so that the flame does not reach the surface of the continuous casting material 2 (S203).

  Thereafter, the cutting overall control unit 7a of the control device 7 outputs a switching signal for switching the speed control method to the V / f control method to the control switching unit 8c of the inverter device 8. When the speed control switching signal is input, the control method switching unit 8c in the inverter device 8 switches the speed control method from the vector control method to the V / f control method using the changeover switch 8d (S204). When the switching is completed, the control method switching unit 8c outputs a switching completion signal to the control device 7, and when the switching completion signal is input, the control device 7 indicates that the speed control method has been switched to the V / f control method. Determination is made (S205).

  The cutting overall control unit 7a of the control device 7 sends the inverter device 8 that controls and drives the gas torch moving unit 1j on the side where the speed detector 1g detects an abnormality in the pair of gas torch moving units 1j to the direction opposite to the cutting direction. And a backward speed command value set in advance in the control device 7 to output the gas torch moving part 1j from above the continuous cast material 2 being cut out of the line. (S206). The control device 7 determines that the gas torch moving unit 1j has moved back out of the line (S207) when detected by a backward limit sensor (not shown) provided outside the transfer line (S207), and stops at the inverter device 8. A command is output and the gas torch moving part 1j is stopped (S208).

(V / f control method)
The above-mentioned V / f control system controls the ratio of the voltage (Voltage) output from the inverter device 8 to the induction motor 1f and its frequency (Frequency), thereby keeping the magnetic flux of the induction motor 1f constant and variable speed control. However, at low speed, the required magnetic flux cannot be secured due to the voltage drop of the primary resistance in the induction motor 1f, and the torque is reduced. Therefore, it is not suitable for speed control in a low speed region such as a cutting process and a cutting process. . However, it is sufficient to perform a retreat operation irrelevant to cutting at a non-low speed range, for example, at a speed that is 1/5 or more of the fast-forward speed at the time of detecting the end face, and the present invention utilizes the feature.

  As described above, the gas torch whose speed detector 1g is normal among the pair of gas torch moving portions 1j continues to cut the continuous cast material 2 regardless of the other failure. Since the other moving device that should have become an obstacle is retracted, the continuous cast material 2 can be cut to the end.

<Other embodiments>
In the above embodiment, the control device 7 includes an I / O input / output board such as a LAN board for network connection, an input / output device such as a keyboard and a mouse, an I / O device with other peripheral measurement devices, an HDD, a DVD. The hardware is configured by using an external storage device such as a RAM and a semiconductor memory device, and a computer (A) having a computer = display for displaying control inputs and control states. Then, the control device 7 is realized by recording and loading a computer program that causes the computer to execute information processing of each step of S100 to S103 and S200 to S208 in the external storage device or the built-in memory. The present invention can be implemented.

  In addition, the inverter device 8 is also configured in hardware by combining a known vector control type control device, a known V / f control type control device, and the computer (B) having the above configuration. Can do. Of course, the computer (A) may be used in the configuration of the inverter device.

  In the first embodiment, the embodiment in which the gas torch is one pair (two units) has been described as an example. However, the continuous casting material cutting apparatus and method of the present invention are not limited to this, and it is apparent that the present invention can be extended and applied to a cutting apparatus having three or more gas torches.

It is a schematic side view of arrangement | positioning of the gas type cutting device in a continuous casting installation. It is a front view (seen in a production line direction) of a gas cutting device. It is a figure which shows an example of an end surface detector position and a torch speed pattern. It is a perspective view which shows the outline of a structure of a gas torch moving apparatus. It is a schematic block diagram of the cutting | disconnection control system of the cutting device in embodiment of this invention. It is a speed detector abnormality determination flowchart in the control apparatus in an embodiment of the present invention. It is a flowchart at the time of speed detector abnormality determination in the control device in the embodiment of the present invention. It is an internal structure function figure of a control device and an inverter device in an embodiment of the invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Gas type cutting device 1a ... Carriage 1b ... Clamping device 1c ... Gas torch 1d ... End face detector 1e ... Cable bear 1f for gas torch moving device ... Gas torch drive induction Electric motor 1g ... Gas torch drive speed detector 1h ... Gas torch moving device side pinion 1i ... Dolly side moving rack 1j ... Gas torch moving part 2 ... Continuous casting material 3 ... Slab 4 ... Transport roll 5 ... Mold 6 ... Pinch roll 7 ... Control device 8 ... Inverter device 9 ... Host computer 10 ... Operation screen 11 ... Length measuring device 12 .... Light transmission detector 13 ... Other incidental devices

Claims (3)

In the continuous cast material production line, the cart is movable in the direction of movement of the continuous cast material, which is the direction of the production line, and a gas torch for heating and cutting the continuous cast material, and the cart in the direction perpendicular to the production line direction. Continuous casting material comprising a plurality of gas torch moving parts movable above, a plurality of induction motors provided in each of the plurality of gas torch moving parts, and a plurality of speed detectors for detecting the rotation speed of the induction motors Cutting device,
A plurality of inverter devices each including a vector control method control unit and a V / f control method control unit that are alternatively operated to control and drive each of the plurality of gas torch moving units;
A control device for controlling the cutting operation of the continuously cast material by controlling the plurality of gas torch moving units and the plurality of inverter devices;
The control device operates the vector control method control unit during normal cutting operation to move the gas torch moving unit, and detects occurrence of an abnormality related to the movement of the gas torch moving unit by any of the plurality of speed detectors. In some cases, the gas torch moving part whose rotational speed has been detected by the speed detector is operated by switching to the V / f control system control part, thereby retracting the gas torch moving part from the continuous cast material. A continuous casting material cutting device, wherein a cutting operation by a gas torch moving part is executed. The controller is
An abnormality detection unit that detects the occurrence of an abnormality related to the movement of the gas torch moving unit based on the actual number of revolutions measured by the speed detector and outputs a speed abnormality detection signal;
Based on the preset slab cutting schedule, it controls the cutting operation as a whole. Based on the speed abnormality detection signal, the control method of the inverter device of the gas torch moving part in which the abnormality is detected is controlled by the vector control system control unit. Cutting overall control unit for switching from V to f / V control method control unit,
The cutting according to claim 1, further comprising: a speed control unit that outputs each of the gas torch moving units to start / stop and a speed command value to each inverter device for the plurality of gas torch moving units based on an instruction from the cutting overall control unit. apparatus. A gas cutting method for cutting a continuous cast material into a slab using the gas cutting device according to claim 1 or 2,
A step of moving the gas torch moving unit by operating the vector control method control unit of the inverter device during normal cutting operation;
When the speed detector detects the occurrence of an abnormality related to the movement of the gas torch moving unit, the inverter device is instructed to switch the control of the gas torch moving unit from the vector control method control unit to the V / f control method control unit. Run,
And a step of retracting the gas torch moving part from the continuous cast material and executing a cutting operation by another gas torch moving part.

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