Oxygen trepanning device

Abstract

An oxygen tapping device (8) is provided with: a transport device (10) that transports an oxygen lance tube so that the tip of the oxygen lance tube for guiding oxygen is disposed in a pouring hole (3) provided in the lower part of a molten steel ladle (2) and in a position heated by a heat source located at a position distant from the pouring hole (3); an ignition control unit (114) that controls the transport device (10) so that the tip section is disposed at a position heated by the heat source and the tip section is ignited; and a hole-opening control unit (115) that controls the transport device (10) so that the ignited tip section is disposed within the pouring hole (3) and the blocked pouring hole (3) is opened.

Description

Technical Field

[0001] The present disclosure relates to an oxygen opening device. Background Art

[0002] Patent Document 1 discloses an automatic oxygen hole opening device. The automatic oxygen hole opening device includes a tube feeding device, a deflecting device, a rotating device, and an oxygen supply device. The tube feeding device includes a reel around which an oxygen injection tube is wound, a feed roller that unwinds the oxygen injection tube from the reel and continuously feeds it, and a tube guide that guides the oxygen injection tube from below into a sliding gate nozzle. The deflecting device rotates the tube feeding device vertically. The rotating device rotates the tube feeding device horizontally. The oxygen supply device supplies oxygen to the oxygen injection tube.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 6-182526 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] The present disclosure provides an oxygen opening device that is effective in opening a clogged pouring hole of a ladle at a timely manner with high reliability.

[0008] Solutions for solving problems

[0009] An oxygen hole opening device according to a technical solution of the present disclosure comprises: a conveying device that conveys the oxygen lance tube so as to position the tip end portion of the oxygen lance tube for guiding oxygen at a pouring hole provided at the lower portion of a ladle for molten steel and at a position heated by a heat source located away from the pouring hole; an ignition control unit that controls the conveying device so as to position the tip end portion at a position heated by the heat source and ignite the tip end portion; and a hole opening control unit that controls the conveying device so as to position the ignited tip end portion in the pouring hole and open the blocked pouring hole.

[0010] If a blocked pouring hole is not opened promptly, the molten steel in the ladle will solidify without being drained, potentially forcing the entire ladle and the entire molten steel to be discarded. Therefore, opening the pouring hole is a critical task. In contrast, with this device, a pre-ignited oxygen lance is inserted into the pouring hole. This eliminates the need to wait for ignition within the pouring hole; the continuous combustion of the oxygen lance within the pouring hole allows for timely opening of the pouring hole. Consequently, the pouring hole can be opened promptly and reliably, unaffected by residual heat within the pouring hole.

[0011] Alternatively, the ignition control unit may control the conveying device so that the tip portion is positioned to be heated by the heat source, using the molten steel stored outside the ladle as a heat source. By effectively utilizing the heat of the molten steel for ignition of the tip portion, the device structure can be simplified.

[0012] Alternatively, an ignition device may be further provided around the ladle, and the ignition control unit may control the conveying device so as to position the tip portion at a position where it is heated by the heat source, using the ignition device as a heat source. Even when the amount of molten steel is small and it is difficult to position the tip portion within the molten steel, the tip portion can be ignited.

[0013] Alternatively, a nozzle for guiding molten steel from the pouring hole may be installed below the pouring hole, and the hole opening control unit may control the conveying device so that the ignited tip portion is positioned upward in a standby position adjacent to the nozzle, and after the nozzle is removed, the ignited tip portion is positioned within the pouring hole. This allows the oxygen lance tube to be quickly inserted into the pouring hole after the nozzle is removed, allowing the pouring hole to be opened more quickly.

[0014] Alternatively, a second conveying device may be provided to convey the nozzle that guides the molten steel from the pouring hole between an installation position below the pouring hole and a retreated position. This allows operations on the nozzle and the oxygen lance tube to be performed in parallel, thereby enabling the pouring hole to be opened more quickly.

[0015] Alternatively, the apparatus may further include a blockage detection unit for detecting blockage of the pouring hole based on the state of a gate opening and closing the pouring hole and a change in the weight of a tundish containing molten steel guided by the nozzle. The ignition control unit may control the conveyor device so that the tip portion is positioned relative to the heat source after the blockage detection unit detects blockage of the pouring hole and before the second conveyor device retracts the nozzle from the mounting position. By performing the ignition of the tip portion and the retraction of the nozzle in parallel, the time from detection of blockage to opening the hole can be further shortened.

[0016] Alternatively, the hole opening control unit may control the conveying device so that the ignited tip portion is positioned upward in a standby position adjacent to the nozzle before the second conveying device retracts the nozzle from the mounting position, and the ignited tip portion is positioned within the pouring hole after the second conveying device retracts the nozzle from the mounting position. This allows for more rapid insertion of the ignited oxygen lance barrel after the nozzle has retracted.

[0017] Alternatively, the device may further include: a sensor for acquiring three-dimensional data of the pouring hole from outside the ladle; and a position detection unit for detecting the position of the pouring hole based on the three-dimensional data acquired by the sensor, wherein the opening control unit positions the tip portion within the pouring hole based on the position of the pouring hole detected by the position detection unit. This enables the oxygen lance tube to be inserted into the pouring hole with high precision.

[0018] The apparatus may further include: a second sensor for acquiring image data of the tip portion after ignition; and a combustion detection unit for detecting whether combustion of the tip portion is continuing based on the image data acquired by the second sensor. If the combustion detection unit detects that combustion of the tip portion is not continuing, the ignition control unit controls the conveying device so as to reposition the tip portion to a position where it is heated by the heat source. This allows for more reliable insertion of the oxygen lance tube with the tip portion ignited.

[0019] Alternatively, the conveying device may include a lance holder that holds the oxygen lance tube; a base that is fixed around the bottom of the ladle; and a multi-jointed arm that connects the lance holder to the base and adjusts the position and posture of the lance holder relative to the base. This allows both ignition and hole drilling to be easily accomplished using a single device.

[0020] Alternatively, a force sensor may be provided on the lance holder, and the hole opening control unit may control the conveying device based on the detection result of the force sensor so as to insert the tip portion into the pouring hole while limiting the propulsion force of the tip portion into the pouring hole. This can easily prevent the liner in the pouring hole from being damaged by collision with the oxygen lance barrel.

[0021] Alternatively, the hole opening control unit may control the conveying device so that the tip portion contacts the inner surface of the casting hole at multiple locations when the tip portion is inserted into the casting hole to a first depth, calculate the center position of the casting hole based on the position of the tip portion when contacting the multiple locations, control the conveying device so that the center position of the tip portion coincides with the center position of the casting hole, and control the conveying device so that the tip portion is inserted to a second depth deeper than the first depth. By aligning the center position of the tip portion with the center position of the casting hole when the tip portion is inserted to the first depth, damage to the liner can be more reliably avoided until the tip portion reaches the second depth.

[0022] The invention may further include a rack for storing a plurality of oxygen lance tubes at a position below and away from the ladle; and a lance replacement control unit for controlling the conveying device so that used oxygen lance tubes are placed on the rack and so that unused oxygen lance tubes stored on the rack are held in the lance holder. By automating the replacement of oxygen lance tubes with respect to the lance holder, it is possible to further reduce labor in the oxygen tapping operation.

[0023] Effects of the Invention

[0024] According to the present disclosure, it is possible to provide an oxygen gas opening device that is effective in opening a clogged pouring hole of a ladle at a timely manner with high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1It is a schematic diagram illustrating the structure of a continuous casting system.

[0026] Figure 2 This is a block diagram illustrating the functional structure of a control system.

[0027] Figure 3 This is a block diagram illustrating the hardware configuration of a control system.

[0028] Figure 4 This is a flow chart illustrating a pouring process from a ladle to a tundish.

[0029] Figure 5 This is a flow chart illustrating the oxygen gas opening process.

[0030] Figure 6 This is a schematic diagram illustrating a state where an oxygen lance is ignited.

[0031] Figure 7 This is a schematic diagram illustrating a state of waiting for the nozzle to retreat.

[0032] Figure 8 This is a flow chart illustrating the oxygen gas opening process.

[0033] Figure 9 This is a schematic diagram illustrating a state where the insertion operation of the oxygen lance tube is started.

[0034] Figure 10 This is a flow chart illustrating the oxygen gas opening process.

[0035] Figure 11 This is a flowchart illustrating the process of adjusting the position of the oxygen lance.

[0036] Figure 12 It is a schematic diagram illustrating the relationship between the position of the tip portion and the center position of the pouring hole in the position adjustment step. DETAILED DESCRIPTION

[0037] Hereinafter, the embodiment will be described in detail with reference to the accompanying drawings. In the description, the same elements or elements having the same functions are denoted by the same reference numerals, and redundant descriptions are omitted.

[0038] 〔Continuous Casting System〕

[0039] Figure 1 It is a schematic diagram illustrating the structure of a continuous casting system. Figure 1The continuous casting system 1 shown is a system for producing steel sheets using continuous casting. It includes a ladle 2, a pouring hole 3, a gate 4, a nozzle 5, a tundish 6, a mold 7, and an oxygen tapping device 8. The ladle 2 holds molten steel produced in a blast furnace or electric furnace. The ladle 2 has a pouring hole 3 and a gate 4 at its lower portion. The pouring hole 3 discharges the molten steel downward. The gate 4 opens and closes the pouring hole 3.

[0040] The nozzle 5 guides the molten steel from the pouring hole 3 downward. The tundish 6 receives the molten steel guided from above by the nozzle 5 and discharges it downward. The mold 7 receives the molten steel discharged from the tundish 6 from above, shaping it while conveying it downward. The molten steel gradually solidifies as it passes through the mold 7. The molten steel conveyed downward through the mold 7 is conveyed by multiple conveyor rollers and cut into steel sheets using a gas cutter or the like.

[0041] The oxygen hole opening device 8 is a device that, when the pouring hole 3 is clogged by molten steel that has become highly viscous or solidified within the ladle 2, places the tip 33 of an oxygen lance 30, which introduces oxygen, within the pouring hole 3 and uses the combustion heat of the oxygen lance 30 to open the pouring hole 3. Since the oxygen hole opening device 8 performs the opening operation of the pouring hole 3 instead of the operator using the oxygen lance 30, the burden on the operator can be greatly reduced.

[0042] The oxygen opening device 8 includes a conveying device 10 for conveying the oxygen lance 30 and a control system 100 for controlling the conveying device 10. During continuous casting, if the blocked pouring hole 3 is not opened in a timely manner, the molten steel in the ladle 2 will solidify without being discharged, and there may be cases where all the molten steel in the ladle 2 and the ladle 2 must be discarded. Therefore, the opening of the pouring hole 3 is a critical operation.

[0043] Therefore, the conveying device 10 is configured to convey the oxygen lance tube 30 so that the tip portion 33 is positioned within the pouring hole 3 and is heated by a heat source located away from the pouring hole 3. The control system 100 is configured to control the operation of the conveying device 10 so that the tip portion 33 is positioned near the heat source to ignite the tip portion 33, and to control the operation of the conveying device 10 so that the ignited tip portion 33 is positioned within the pouring hole 3 to open the blocked pouring hole 3.

[0044] Thus, the pre-ignited oxygen lance 30 is inserted into the pouring hole 3. Therefore, without waiting for ignition inside the pouring hole 3, the pouring hole 3 can be opened at the right time by utilizing the continuous combustion of the oxygen lance 30 inside the pouring hole 3. Therefore, the pouring hole 3 can be opened at the right time with high reliability without being affected by the residual heat inside the pouring hole 3.

[0045] The conveying device 10 can be constructed arbitrarily as long as it can arrange the tip portion 33 in the pouring hole 3 and the heat source at a position away from the pouring hole 3. As an example, Figure 1 The transport device 10 shown is composed of a serial type vertical multi-joint robot. For example, the transport device 10 includes a gun holding portion 11, a base 12, and a multi-joint arm 13.

[0046] The gun holding portion 11 holds the oxygen gun barrel 30. For example, the gun holding portion 11 is a master device (master) of the automatic tool changer, and holds the tool adapter 15 pre-assembled to the oxygen gun barrel 30. For example, the oxygen gun barrel 30 has a support portion 31 extending from the tool adapter 15 and an insertion portion 32 bent relative to the support portion 31. The support portion 31 is connected to an oxygen supply source using a hose (not shown), and the oxygen gun barrel 30 guides oxygen from the support portion 31 to the insertion portion 32. The oxygen guided to the insertion portion 32 is blown out from the end of the insertion portion 32. In this structure, the end of the insertion portion 32 is the top end portion 33 of the oxygen gun barrel 30. The gun holding portion 11 is configured to switch between a locked state for maintaining the tool adapter 15 and an unlocked state for releasing the tool adapter 15 according to a control signal.

[0047] The base 12 is fixed around the bottom of the ladle 2. For example, the base 12 is fixed to the stage 9 provided around the tundish 6 located below the ladle 2. The multi-jointed arm 13 extends to connect the gun holder 11 and the base 12, and the position and posture of the gun holder 11 relative to the base 12 are changed by the movement of multiple joint axes.

[0048] The multi-joint arm 13 has a plurality of drive shafts 14 for driving the plurality of joint axes. For example, the multi-joint arm 13 has six drive shafts 14 so as to be able to change the position of the gun holder 11 in three mutually perpendicular directions and the posture of the gun holder 11 around these three directions.

[0049] Thus, the conveyor device 10, which is comprised of a multi-jointed robot, can easily perform both ignition and drilling operations using a single device. However, as mentioned above, the conveyor device 10 is not limited to a vertical multi-jointed robot. For example, the conveyor device 10 may also be comprised of a so-called horizontal multi-jointed robot, a lifting actuator that raises and lowers the oxygen lance barrel 30, and a rotary actuator that rotates the oxygen lance barrel 30 to change the orientation of the tip portion 33. For example, the conveyor device 10 may also be comprised of an XY stage that moves the oxygen lance barrel 30 horizontally, a lifting actuator that raises and lowers the oxygen lance barrel 30, and a rotary actuator that rotates the oxygen lance barrel 30 to change the orientation of the tip portion 33.

[0050] The continuous casting system 1 may further include an ignition device 41 as the heat source. The ignition device 41 is disposed around the ladle 2. For example, the ignition device 41 is disposed around the tundish 6 below the ladle 2. As an example, the ignition device 41 is disposed on the stage 9.

[0051] For example, the ignition device 41 is a burner that uses gas to generate a flame. The location heated by the ignition device 41 is within the flame generated by the ignition device 41. Alternatively, the ignition device 41 is an induction heating device that uses electromagnetic induction from a coil to heat the tip portion 33. In this case, the location heated by the ignition device 41 is within the coil. Alternatively, the ignition device 41 is a grinder that uses friction to heat the tip portion 33. In this case, the location heated by the ignition device 41 is the location in contact with the grinder.

[0052] The continuous casting system 1 may further include a sensor 42. The sensor 42 acquires three-dimensional data of the pouring hole 3 from outside the ladle 2. For example, the sensor 42 acquires three-dimensional data of the pouring hole 3, which opens to the outside of the ladle 2 through the gate 4. Three-dimensional data represents the three-dimensional shape of an object arranged in three-dimensional space using, for example, a sequence of points in the three-dimensional space. The three-dimensional data acquired by the sensor 42 can be used to adjust the position of the tip portion 33 relative to the pouring hole 3.

[0053] Sensor 42 is, for example, a Time-of-Flight (TOF) camera. A TOF camera detects the distance to an object based on the time it takes for light irradiated by the object to be reflected by the object and enter an imaging unit. The TOF camera captures distance image data containing distance information to the object for each pixel as three-dimensional data.

[0054] The sensor 42 can be any sensor as long as it can acquire three-dimensional data. For example, the sensor 42 can also be a stereo camera or a laser scanning three-dimensional shape sensor. The sensor 42 can also acquire information on the position and posture of a mark used for image recognition whose relative position relative to the pouring hole 3 is known as three-dimensional data. Based on the position and posture of the mark whose relative position relative to the pouring hole 3 is known, the position and posture of the pouring hole 3 can be derived, so the position and posture of the mark are also included in the three-dimensional data of the pouring hole 3. The sensor 42 can also be fixed to a part (such as the gun holding part 11) whose position and posture are changed by the conveying device 10. In this case, by using the conveying device 10 to change the position and posture of the sensor 42, the sensor 42 can be used in common to acquire three-dimensional data of various objects. In addition, by combining the three-dimensional data acquired from multiple viewpoints, the position of the pouring hole 3 can also be identified with higher accuracy.

[0055] The continuous casting system 1 may also include a second sensor 43. The second sensor 43 acquires image data of the top portion 33 after ignition. The second sensor 43 may be, for example, a black and white visible light camera or a color visible light camera. For example, the second sensor 43 is configured to be able to capture the top portion 33 disposed in a standby position P11 adjacent to the upward nozzle 5 in order to wait for the nozzle 5 to retreat. The image data acquired by the second sensor 43 can be used, for example, to detect a situation in which the combustion of the top portion 33 is interrupted while waiting for the nozzle 5 to retreat, thereby requiring re-ignition of the top portion 33. In addition, the second sensor 43 may also be fixed to a portion (such as the gun holding portion 11) whose position and posture are changed by the conveying device 10. In this case, by using the conveying device 10 to change the position and posture of the second sensor 43, the second sensor 43 can be used to acquire image data of various objects. In addition, the blind spot of the second sensor 43 can also be reduced, thereby detecting the state of the top portion 33 with higher reliability.

[0056] The continuous casting system 1 may further include a force sensor 16. The force sensor 16 detects the force acting on the oxygen lance tube 30. The force sensor 16 detects at least the force acting on the oxygen lance tube 30 along the insertion portion 32. The force sensor 16 may also detect the force acting on the oxygen lance tube 30 in a direction intersecting the insertion portion 32.

[0057] For example, the force sensor 16 is provided in the gun holding portion 11. Examples of the force sensor 16 include a strain gauge load sensor and the like.

[0058] The continuous casting system 1 may further include a rack 44. The rack 44 stores a plurality of oxygen lance tubes 30 at a position below and away from the ladle 2. For example, the rack 44 is disposed on the aforementioned stage 9. A tool adapter 15 may be pre-assembled with each of the plurality of oxygen lance tubes 30 stored in the rack 44. This allows the conveying device 10 to replace a used oxygen lance tube 30 with a new one.

[0059] The rack 44 may be divided into a used rack for storing used oxygen lance tubes 30 and an unused rack for storing unused oxygen lance tubes 30. The used rack and the unused rack may be adjacent to each other, arranged one above the other, or arranged separately from each other.

[0060] The continuous casting system 1 may further include a weight sensor 45. The weight sensor 45 detects the weight of the tundish 6. The detection result of the weight sensor 45 can be used to detect blockage of the pouring hole 3, etc.

[0061] The continuous casting system 1 may further include a second conveying device 20. The second conveying device 20 conveys the nozzle 5 between an installation position P1 below the pouring hole 3 and a retreat position P2 that is retreated from the installation position P1. The retreat position P2 is located approximately below the ladle 2. For example, the second conveying device 20 rotates about a vertical axis at a position away from below the ladle 2, thereby conveying the nozzle 5 along an arc-shaped track between the installation position P1 and the retreat position P2.

[0062] By providing the second conveying device 20 for conveying the nozzle 5 independently of the continuous casting system 1 for conveying the oxygen lance 30, operations on the nozzle 5 and the oxygen lance 30 can be performed in parallel. Therefore, the pouring hole 3 can be opened more quickly.

[0063] Figure 2 is a block diagram illustrating the structure of a control system. Figure 2 As shown, the control system 100 includes an opening and closing control unit 111 , a clogging detection unit 112 , a nozzle transport control unit 113 , an ignition control unit 114 , and an opening control unit 115 as functional components (hereinafter referred to as “functional blocks”).

[0064] The opening and closing control unit 111 opens and closes the gate 4. The blockage detection unit 112 detects blockage of the pouring hole 3 based on the state of the gate 4 and the weight change of the tundish 6. Blockage, in this context, means a state in which, despite the gate 4 opening the pouring hole 3, the flow of molten steel from the pouring hole 3 is completely or significantly impeded by, for example, increased viscosity or solidification of the molten steel. For example, the blockage detection unit 112 receives information about the state of the gate 4 from the opening and closing control unit 111 and information about the weight of the tundish 6 from the weight sensor 45. After the gate 4 opens the pouring hole 3, the blockage detection unit 112 obtains multiple detection results from the weight sensor 45 in a time series and calculates the weight change of the tundish 6 per unit time based on these multiple detection results. The blockage detection unit 112 detects blockage of the pouring hole 3 when the calculated weight change is less than a predetermined threshold value. The threshold value is preset to a value lower than the weight change expected if the pouring hole 3 were not blocked.

[0065] The nozzle transport control unit 113 controls the second transport device 20 to transport the nozzle 5 between the installation position P1 and the retreat position P2. For example, the nozzle transport control unit 113 uses the second transport device 20 to position the nozzle 5 at the installation position P1 before the opening and closing control unit 111 controls the gate 4 to open the pouring hole 3. After the opening and closing control unit 111 controls the gate 4 to open the pouring hole 3, if the clogging detection unit 112 detects clogging of the pouring hole 3, the nozzle transport control unit 113 uses the second transport device 20 to transport the nozzle 5 from the installation position P1 to the retreat position P2.

[0066] The ignition control unit 114 controls the transport device 10 so that the tip portion 33 is positioned in a position heated by the heat source and the tip portion 33 is ignited. For example, the ignition control unit 114 controls the transport device 10 so that the gun holder 11 is moved to a target position and posture predetermined so that the tip portion 33 is positioned in a position heated by the heat source. For example, the ignition control unit 114 uses inverse kinematics or the like to calculate the operating angles of the multiple drive shafts 14 required to move the gun holder 11 from its current position and posture to the target position and posture, and then operates the multiple drive shafts 14 based on the calculated angles.

[0067] The ignition control unit 114 can control the conveying device 10 so that the tip portion 33 is positioned to be heated by the heat source, using the molten steel stored outside the ladle 2. For example, the ignition control unit 114 can control the conveying device 10 so that the tip portion 33 is positioned near or within the molten steel contained in the tundish 6. By effectively utilizing the heat of the molten steel for ignition of the tip portion 33, the device structure can be simplified.

[0068] The ignition control unit 114 can also control the conveying device 10 so that the tip portion 33 is positioned at a position heated by the heat source, using the ignition device 41 as a heat source. Even when the amount of molten steel accumulated in the tundish 6 or the like is small, making it difficult to position the tip portion 33 near or within the molten steel, the tip portion 33 can be ignited.

[0069] When the ignition device 41 is a burner, the ignition control unit 114 controls the conveying device 10 so that the tip portion 33 is positioned within the flame generated by the ignition device 41. When the ignition device 41 is an induction heating device, the ignition control unit 114 controls the conveying device 10 so that the tip portion 33 is positioned within the coil. When the ignition device 41 is a grinder, the ignition control unit 114 controls the conveying device 10 so that the tip portion 33 is positioned in contact with the grinder.

[0070] The hole opening control unit 115 controls the conveying device 10 so that the ignited tip portion 33 is positioned within the pouring hole 3, thereby opening the blocked pouring hole 3. For example, the hole opening control unit 115 controls the conveying device 10 so that the insertion portion 32 is inserted into the pouring hole 3, thereby positioning the ignited tip portion 33 within the pouring hole 3. The combustion heat of the pouring hole 3 is used to melt the molten steel that has become highly viscous or solidified, thereby clearing the blockage of the pouring hole 3.

[0071] The hole-drilling control unit 115 can also control the conveying device 10 so that the ignited tip portion 33 is positioned upward at a standby position P11 adjacent to the nozzle 5, and then positioned within the pouring hole 3 after the nozzle 5 is removed. For example, the hole-drilling control unit 115 can control the conveying device 10 so that the gun holder 11 is moved to a predetermined first target position and first target posture, with the support portion 31 extending horizontally from the tool adapter 15 below the standby position P11, the insertion portion 32 extending upward from the end of the support portion 31, and the tip portion 33 positioned at the standby position P11. For example, the hole-drilling control unit 115 uses inverse kinematics or the like to calculate the operating angles of the multiple drive shafts 14 required to move the gun holder 11 from its current position and posture to the first target position and first target posture, and then operates the multiple drive shafts 14 based on the calculated angles. Furthermore, the orientation of the tip portion 33 when positioned at the standby position P11 is not necessarily limited to upward. For example, the hole opening control unit 115 may control the conveying device 10 so as to arrange the distal end portion 33 at the standby position P11 facing the horizontal direction.

[0072] After the nozzle 5 is removed, the hole opening control unit 115 controls the conveying device 10 so that the gun holder 11 is moved to the second target position and second target posture that are predetermined so that the upward-pointing tip 33 moves from below toward the center of the pouring hole 3. For example, the hole opening control unit 115 uses inverse kinematics or the like to calculate the operating angles of the multiple drive shafts 14 required to move the gun holder 11 from the first target position and first target posture to the second target position and second target posture, and operates the multiple drive shafts 14 based on the calculated results.

[0073] Thereafter, the hole-drilling control unit 115 controls the conveying device 10 so that the gun holder 11 is linearly displaced to a third target position and a third target posture that are predetermined so that the insertion portion 32 is inserted into the casting hole 3 and the tip portion 33 is positioned within the casting hole 3. For example, the hole-drilling control unit 115 uses inverse kinematics or the like to calculate the operating angles of the plurality of drive shafts 14 required to linearly displace the gun holder 11 from its current position and current posture to the third target position and third target posture, and operates the plurality of drive shafts 14 in accordance with the calculated results.

[0074] In this way, by positioning the ignited tip portion 33 upward at the standby position P11 while waiting for the removal of the nozzle 5, the oxygen lance tube 30 can be quickly inserted into the pouring hole 3 after the nozzle 5 is removed, thereby opening the pouring hole 3 more quickly. Removing the nozzle 5 means, for example, retracting the nozzle 5 from under the pouring hole 3 to a position where the oxygen lance tube 30 can be inserted into the pouring hole 3.

[0075] When the continuous casting system 1 further includes a second conveying device 20, the ignition control unit 114 may control the conveying device 10 so that the tip portion 33 is positioned relative to the heat source after the blockage detection unit 112 detects blockage of the pouring hole 3 and before the second conveying device 20 retracts the nozzle 5 from the mounting position P1. The state in which the nozzle 5 is retracted from the mounting position P1 means that the oxygen lance tube 30 can be inserted into the pouring hole 3 by moving the nozzle 5 from the mounting position P1 toward the retracted position P2. By performing the ignition of the tip portion 33 and the retraction of the nozzle 5 from the mounting position P1 in parallel, the time from detection of blockage in the pouring hole 3 to opening of the pouring hole 3 can be further shortened.

[0076] The hole opening control unit 115 can also control the conveying device 10 so that the ignited tip portion 33 is positioned upward at the standby position P11 adjacent to the nozzle 5 before the second conveying device 20 retracts the nozzle 5 from the mounting position P1, and the ignited tip portion 33 is positioned within the pouring hole 3 after the second conveying device 20 retracts the nozzle 5 from the mounting position P1. For example, the hole opening control unit 115 determines whether the nozzle 5 has retracted from the mounting position P1 based on the operating status of the second conveying device 20 controlled by the nozzle conveying control unit 113. This allows the ignited oxygen lance tube 30 to be quickly inserted after the nozzle 5 has retracted.

[0077] The control system 100 may further include a position detection unit 116. The position detection unit 116 detects the position of the pouring hole 3 based on the three-dimensional data acquired by the sensor 42. For example, the position detection unit 116 determines the position and posture of the three-dimensional model within the three-dimensional data by matching a pre-stored three-dimensional model of the pouring hole 3 and its surroundings with the three-dimensional data, and detects the position of the pouring hole 3 based on the determined position and posture of the three-dimensional model.

[0078] If the control system 100 further includes a position detector 116, the hole opening control unit 115 may also position the tip portion 33 within the pouring hole 3 based on the position of the pouring hole 3 detected by the position detector 116. For example, the hole opening control unit 115 may correct the previously determined target position and target posture of the lance holder 11 (e.g., the second target position, the second target posture, and the third target position and posture described above) so that the center axis of the insertion portion 32 is aligned with the center axis of the pouring hole 3 based on the position detected by the position detector 116, and then operate the lance holder 11 in accordance with the corrected target position and target posture. This allows the oxygen lance tube 30 to be inserted into the pouring hole 3 with high precision.

[0079] Based on the detection results of the force sensor 16, the hole opening control unit 115 can also control the conveying device 10 to insert the tip portion 33 into the casting hole 3 while limiting the propulsion force of the tip portion 33 into the casting hole 3. For example, the hole opening control unit 115 calculates the reaction force applied to the insertion of the tip portion 33 based on the detection results of the force sensor 16. If the calculated reaction force exceeds a predetermined reaction force threshold, the hole opening control unit 115 controls the conveying device 10 to reduce the displacement speed of the lance holder 11 until the reaction force is less than the reaction force threshold. This can easily prevent the liner in the casting hole 3 from being damaged by collision with the oxygen lance tube 30.

[0080] The hole-drilling control unit 115 can also cause the conveyor device 10 to align the tip portion 33 with respect to the casting hole 3 based on the detection results of the force sensor 16. For example, the hole-drilling control unit 115 controls the conveyor device 10 so that the tip portion 33 contacts the inner surface of the casting hole 3 at multiple locations, while inserting the tip portion 33 to a first depth within the casting hole 3. For example, the hole-drilling control unit 115 controls the conveyor device 10 so that the tip portion 33 contacts the inner surface of the casting hole 3 at multiple locations, while confirming whether the tip portion 33 contacts the inner surface of the casting hole 3 based on the detection results of the force sensor 16. Each time the tip portion 33 contacts the inner surface of the casting hole 3, the hole-drilling control unit 115 calculates the position of the tip portion 33 at the time of contact based on the position of the gun holder 11. Thus, the position of the tip portion 33 at multiple locations of contact with the inner surface of the casting hole 3 is calculated.

[0081] The drilling control unit 115 calculates the center position of the casting hole 3 based on the position of the tip portion 33 when it contacts the inner surface of the casting hole 3 at multiple locations, and controls the conveying device 10 so that the center position of the tip portion 33 coincides with the center position of the casting hole 3. For example, the drilling control unit 115 controls the conveying device 10 so that the difference between the center position of the casting hole 3 and the center position of the tip portion 33 is zero. The drilling control unit 115 then controls the conveying device 10 so that the tip portion 33 is inserted to a second depth greater than the first depth, while maintaining the center position of the tip portion 33 aligned with the center position of the casting hole 3. By aligning the center position of the tip portion 33 with the center position of the casting hole 3 while the tip portion 33 is inserted to the first depth, damage to the liner can be more reliably avoided until the tip portion 33 reaches the second depth.

[0082] The control system 100 may further include a combustion detection unit 117. The combustion detection unit 117 detects whether the tip portion 33 is continuing to burn based on the image data acquired by the second sensor 43. For example, the combustion detection unit 117 detects whether the tip portion 33 is continuing to burn based on the brightness of the portion corresponding to the tip portion 33 in the image data.

[0083] When the control system 100 further includes a combustion detection unit 117, the hole opening control unit 115 can also control the conveying device 10 so as to reposition the tip portion 33 to a position where it is heated by the heat source when the combustion detection unit 117 detects that the combustion of the tip portion 33 is not continuing. This allows the oxygen lance tube 30 to be inserted more reliably with the tip portion 33 having been ignited.

[0084] The control system 100 may further include a gun replacement control unit 118. The gun replacement control unit 118 controls the conveyor device 10 to place the used oxygen lance 30 on the gate 4 and to hold the unused oxygen lance 30 stored in the rack 44 in the gun holder 11. For example, the gun replacement control unit 118 controls the conveyor device 10 to place the used oxygen lance 30 on the gate 4 and then switch the gun holder 11 from a locked state to an unlocked state. The gun replacement control unit 118 then controls the conveyor device 10 to connect the gun holder 11 to the tool adapter 15 attached to the unused oxygen lance 30 stored in the rack 44 and switch the gun holder 11 from an unlocked state to a locked state. By automating the replacement of the oxygen lance 30 with respect to the gun holder 11, further labor-saving oxygen tapping operations can be achieved.

[0085] Figure 3 This is a block diagram illustrating the hardware structure of the control system. Figure 3 As shown, the control system 100 includes a circuit 190 , which includes a processor 191 , a memory 192 , a storage device 193 , an input / output port 194 , and control circuits 195 , 196 , and 197 .

[0086] The storage device 193 is composed of one or more non-volatile storage devices such as a flash memory or a hard disk. The storage device 193 stores a program for causing the control system 100 to control the operation of the conveyor device 10 by placing the tip portion 33 near a heat source to ignite the tip portion 33, and to control the operation of the conveyor device 10 by placing the ignited tip portion 33 within the pouring hole 3 to open a blocked pouring hole 3. For example, the storage device 193 stores a program for configuring the control system 100 to implement the aforementioned functional blocks.

[0087] Memory 192 is composed of one or more volatile storage devices, such as random access memory. Memory 192 temporarily stores programs loaded from storage device 193. Processor 191 is composed of one or more computing devices, such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). Processor 191 configures control system 100 into the aforementioned functional blocks by executing programs loaded into memory 192. Calculation results from processor 191 are temporarily stored in memory 192.

[0088] The input / output port 194 inputs and outputs information to and from the sensor 42, the second sensor 43, the force sensor 16, the weight sensor 45, and the like in response to requests from the processor 191. The control circuit 195 operates the conveyor device 10 in response to requests from the processor 191. The control circuit 196 operates the second conveyor device 20 in response to requests from the processor 191. The control circuit 197 opens and closes the gate 4 in response to requests from the processor 191. The hardware configuration shown above is merely an example and can be modified as appropriate. For example, the circuit 190 may be divided into multiple circuits capable of communicating with each other.

[0089] 〔Pouring process〕

[0090] As an example of a pouring method, a pouring step of pouring from the ladle 2 to the tundish 6 performed in the continuous casting system 1 is shown. Figure 4 is a flow chart illustrating the pouring process. Figure 4 As shown, the control system 100 first executes steps S01 and S02. In step S01, the opening and closing control unit 111 opens the gate 4 to start the discharge of molten steel from the pouring hole 3. In step S02, the blockage detection unit 112 confirms whether the pouring hole 3 is blocked based on the state of the gate 4 and the weight change of the tundish 6.

[0091] If blockage of the pouring hole 3 is detected in step S02, the control system 100 executes step S03. The details of step S03 will be described below. Next, the control system 100 executes step S04. If blockage of the pouring hole 3 is not detected in step S02, the control system 100 executes step S04 without executing step S03. In step S04, the opening and closing control unit 111 waits for the completion of pouring. For example, based on the detection results of the tundish 6, the opening and closing control unit 111 waits for the pouring amount from the time the gate 4 is opened to reach a predetermined amount.

[0092] Next, the control system 100 executes step S05 . In step S05 , the opening and closing control unit 111 closes the gate 4 to stop the discharge of molten steel from the pouring hole 3 .

[0093] (Oxygen opening process)

[0094] Figure 5 : is a flow chart illustrating the oxygen opening process in step S03. Figure 5 As shown, the control system 100 first executes steps S11 and S12. In step S11, the ignition control unit 114 starts the operation of the transport device 10 to place the tip portion 33 in a position heated by the heat source and ignite the tip portion 33. In step S12, the nozzle transport control unit 113 causes the second transport device 20 to begin transporting the nozzle 5 from the installation position P1 to the retreat position P2. Step S12 may be executed before or simultaneously with step S11.

[0095] Next, the control system 100 executes step S13. In step S13, the ignition control unit 114 waits for the ignition of the tip portion 33. For example, after the tip portion 33 is placed in a position heated by the heat source, the ignition control unit 114 waits for the ignition time (see Figure 6 ).

[0096] Next, the control system 100 executes steps S14 and S15. In step S14, the hole opening control unit 115 controls the conveying device 10 (see FIG. 1 ) so that the ignited tip 33 faces upward and is disposed at the standby position P11 adjacent to the nozzle 5. Figure 7 In step S15 , the combustion detection unit 117 detects whether the combustion of the tip portion 33 is continuing based on the image data acquired by the second sensor 43 .

[0097] If it is determined in step S15 that the combustion of the tip portion 33 is continuing, the control system 100 executes step S16. In step S16, the hole opening control unit 115 checks whether the nozzle 5 has been completely retracted from the installation position P1 based on the operating status of the second conveying device 20 implemented by the nozzle conveying control unit 113.

[0098] If it is determined in step S16 that the nozzle 5 has not been completely retracted from the installation position P1, the control system 100 returns the process to step S15. Thereafter, while confirming that the combustion of the tip portion 33 is continuing, the control system 100 continues to wait for the nozzle 5 to be completely retracted from the installation position P1 until the nozzle 5 is completely retracted from the installation position P1. If it is determined in step S15 that the combustion of the tip portion 33 is not continuing, the control system 100 proceeds to step S17. In step S17, the ignition control unit 114 initiates the operation of the conveying device 10 to re-ignite the tip portion 33 by placing the tip portion 33 in a position heated by the heat source. The control system 100 then returns the process to step S13.

[0099] If it is determined in step S16 that the nozzle 5 has been completely retracted from the installation position P1, Figure 8 As shown, the control system 100 executes steps S21 and S22. In step S21, the position detection unit 116 detects the position of the pouring hole 3 based on the three-dimensional data acquired by the sensor 42. In step S22, the hole opening control unit 115 corrects the predetermined target position and target posture based on the position detected by the position detection unit 116 so that the center axis of the insertion portion 32 is along the center axis of the pouring hole 3. For example, the hole opening control unit 115 corrects the second target position and second target posture predetermined so that the upward-facing tip portion 33 moves from below toward the center of the pouring hole 3, and the third target position and third target posture predetermined so that the tip portion 33 is positioned within the pouring hole 3.

[0100] Next, the control system 100 executes steps S23, S24, and S25. In step S23, the conveying device 10 is controlled so as to insert the tip portion 33 into the pouring hole 3 to the first depth based on the corrected second target position, second target posture, third target position, and third target posture (see FIG. Figure 9 In step S24, the conveying device 10 is controlled so that the tip portion 33 contacts the inner surface of the pouring hole 3 at multiple locations, thereby aligning the pouring hole 3 with respect to the pouring hole 3. The details of step S24 will be described later. In step S25, the hole opening control unit 115 controls the conveying device 10 so that the tip portion 33 is inserted to a second depth greater than the first depth while maintaining the center position of the tip portion 33 aligned with the center position of the pouring hole 3.

[0101] Then, if Figure 10 As shown, the control system 100 executes steps S31, S32, and S33. In step S31, the hole opening control unit 115 waits for the pouring hole 3 to be opened by the combustion heat of the oxygen lance tube 30. For example, the hole opening control unit 115 waits for a predetermined hole opening time to elapse. Alternatively, based on the detection results of the weight sensor 45, the hole opening control unit 115 waits for the weight of the tundish 6 to begin increasing due to the opening of the pouring hole 3. Alternatively, the hole opening control unit 115 waits for the start of liquid discharge from the pouring hole 3 using a camera capable of detecting the state of liquid discharge from the pouring hole 3.

[0102] In step S32, the hole opening control unit 115 controls the conveying device 10 so as to remove the oxygen lance tube 30 from the pouring hole 3. For example, the hole opening control unit 115 controls the conveying device 10 so as to move the lance holder 11 to the second target position and the second target position described above before inserting the oxygen lance tube 30 into the pouring hole 3. In step S33, the hole opening control unit 115 controls the conveying device 10 so as to retract the oxygen lance tube 30 from under the pouring hole 3.

[0103] Next, the control system 100 executes steps S34, S35, S36, and S37. In step S34, the opening and closing control unit 111 closes the gate 4, temporarily halting the discharge of liquid from the pouring hole 3. In step S35, the nozzle transport control unit 113 uses the second transport device 20 to transport the nozzle 5 from the retreat position P2 to the installation position P1. In step S36, the opening and closing control unit 111 opens the gate 4, resuming the discharge of liquid from the pouring hole 3. In step S37, the gun replacement control unit 118 controls the transport device 10 to place the used oxygen lance tube 30 on the gate 4 and to hold the unused oxygen lance tube 30 stored in the rack 44 in the gun holder 11. This completes the oxygen opening process.

[0104] (Position adjustment process)

[0105] Figure 11 : is a flowchart illustrating the position adjustment process of the oxygen lance tube 30 in step S24. Figure 11 As shown, the control system 100 first executes steps S41 and S42. In step S41, the hole opening control unit 115 controls the conveying device 10 so as to displace the gun holder 11 in a horizontal first direction until the oxygen gun tube 30 contacts the inner surface of the pouring hole 3. In step S42, the hole opening control unit 115 calculates the center position P21 of the tip 33 based on the current position and current posture of the gun holder 11 (see Figure 12 ).

[0106] Next, the control system 100 executes steps S43 and S44. In step S43, the hole-opening control unit 115 controls the conveying device 10 to displace the lance holder 11 in the second horizontal direction until the oxygen lance tube 30 contacts the inner surface of the pouring hole 3. In step S44, the hole-opening control unit 115 calculates the center position P22 of the tip portion 33 based on the current position and posture of the lance holder 11.

[0107] Next, the control system 100 executes steps S45 and S46. In step S45, the hole-opening control unit 115 controls the conveying device 10 to displace the lance holder 11 in the horizontal third direction until the oxygen lance tube 30 contacts the inner surface of the pouring hole 3. In step S46, the hole-opening control unit 115 calculates the center position P23 of the tip portion 33 based on the current position and posture of the lance holder 11.

[0108] Next, the control system 100 executes steps S47 and S48. In step S47, the hole opening control unit 115 calculates the center position CP of the pouring hole 3 based on the calculated center positions P21, P22, and P23. For example, the hole opening control unit 115 calculates the center position CP as a position that is equidistant from the center positions P21, P22, and P23. In step S48, the hole opening control unit 115 controls the conveying device 10 so that the center position of the tip portion 33 coincides with the center position of the pouring hole 3. This completes the position adjustment process for the oxygen lance tube 30.

[0109] 〔Summarize〕

[0110] The above embodiment includes the following structures.

[0111] (1) An oxygen hole opening device 8, wherein the oxygen hole opening device 8 comprises: a conveying device 10, which conveys the oxygen lance tube in a manner such that the top end portion of the oxygen lance tube for guiding oxygen is arranged at a pouring hole 3 provided at the lower part of a ladle 2 for molten steel and is heated by a heat source located at a position away from the pouring hole 3; an ignition control unit 114, which controls the conveying device 10 in a manner such that the top end portion is arranged at a position heated by the heat source and the top end portion is ignited; and an opening control unit 115, which controls the conveying device 10 in a manner such that the ignited top end portion is arranged in the pouring hole 3 and the blocked pouring hole 3 is opened.

[0112] If the blocked pouring hole 3 is not opened in a timely manner, the molten steel in the ladle 2 will solidify without being drained, and the entire molten steel and the ladle 2 may have to be discarded. Therefore, opening the pouring hole 3 is a critical task. In contrast, with this device, a pre-ignited oxygen lance is inserted into the pouring hole 3. Therefore, the pouring hole 3 can be opened in a timely manner by utilizing the continuous combustion of the oxygen lance in the pouring hole 3, without having to wait for ignition in the pouring hole 3. Consequently, the pouring hole 3 can be opened in a timely manner with high reliability, without being affected by residual heat in the pouring hole 3.

[0113] (2) The oxygen opening device 8 according to (1), wherein the ignition control unit 114 controls the conveying device 10 so that the tip portion is positioned to be heated by the heat source, using the molten steel accumulated outside the ladle 2 as the heat source.

[0114] By effectively utilizing the heat of the molten steel for ignition at the tip portion, the device structure can be simplified.

[0115] (3) The oxygen hole opening device 8 according to (1), wherein the oxygen hole opening device 8 further includes an ignition device 41 arranged around the ladle 2, and the ignition control unit 114 uses the ignition device 41 as a heat source to control the conveying device 10 in a manner such that the top end portion is arranged at a position heated by the heat source.

[0116] Even when the amount of molten steel accumulated is small and it is difficult to arrange the tip portion in the molten steel, the tip portion can be ignited.

[0117] (4) An oxygen opening device 8 according to any one of (1) to (3), wherein a nozzle 5 for guiding molten steel from the pouring hole 3 is installed below the pouring hole 3, and the opening control unit 115 controls the conveying device 10 in such a manner that the ignited top end is directed upward and arranged at a standby position P11 adjacent to the nozzle 5, and the ignited top end is arranged in the pouring hole 3 after the nozzle 5 is removed.

[0118] After the nozzle 5 is removed, the oxygen lance tube can be quickly inserted into the pouring hole 3 , so that the pouring hole 3 can be opened more quickly.

[0119] (5) An oxygen hole opening device 8 according to any one of (1) to (4), wherein the oxygen hole opening device 8 further includes a second conveying device 20, which conveys the nozzle 5 that guides the molten steel coming out of the pouring hole 3 between an installation position below the pouring hole 3 and a retreat position retreated from the installation position.

[0120] The operation on the nozzle 5 and the operation on the oxygen lance can be performed in parallel. Therefore, the pouring hole 3 can be opened more quickly.

[0121] (6) The oxygen hole opening device 8 according to (5), wherein the oxygen hole opening device 8 further includes a blockage detection unit, which detects blockage of the pouring hole 3 based on the state of the gate 4 that opens and closes the pouring hole 3 and the weight change of the ladle 6 that receives the molten steel guided by the nozzle 5, and the ignition control unit 114 controls the conveying device 10 in such a manner that the top end portion is arranged at the heat source after the blockage detection unit detects the blockage of the pouring hole 3 and before the second conveying device 20 retracts the nozzle 5 from the installation position.

[0122] By performing the operation of igniting the tip portion and the operation of retracting the nozzle 5 in parallel, the time from detection of clogging to opening of the hole can be further shortened.

[0123] (7) The oxygen hole opening device 8 according to (6), wherein the hole opening control unit 115 controls the conveying device 10 in such a manner that the ignited top end portion is directed upward and arranged at the standby position P11 adjacent to the nozzle 5 before the second conveying device 20 retracts the nozzle 5 from the installation position, and the ignited top end portion is arranged in the pouring hole 3 after the second conveying device 20 retracts the nozzle 5 from the installation position.

[0124] After the nozzle 5 has been retracted, the ignited oxygen lance can be inserted more quickly.

[0125] (8) The oxygen hole opening device 8 according to any one of (1) to (7), wherein the oxygen hole opening device 8 further comprises: a sensor 42, which obtains three-dimensional data of the pouring hole 3 from outside the ladle 2; and a position detection unit 116, which detects the position of the pouring hole 3 based on the three-dimensional data obtained by the sensor 42, and the hole opening control unit 115 arranges the top end portion in the pouring hole 3 based on the position of the pouring hole 3 detected by the position detection unit 116.

[0126] The oxygen lance tube can be inserted into the pouring hole 3 with high precision.

[0127] (9) The oxygen hole opening device 8 according to (8), wherein the oxygen hole opening device 8 further comprises: a second sensor 43, which obtains image data of the top end portion after ignition; and a combustion detection unit 117, which detects whether the combustion of the top end portion is continuing based on the image data obtained by the second sensor 43, and when the combustion detection unit 117 detects that the combustion of the top end portion is not continuing, the ignition control unit 114 controls the conveying device 10 in a manner that reconfigures the top end portion to a position where it is heated by a heat source.

[0128] The operation of inserting the oxygen lance tube in a state where the tip portion has been ignited can be performed more reliably.

[0129] (10) An oxygen opening device 8 according to any one of (1) to (9), wherein the conveying device 10 comprises: a gun holding portion 11 which holds the oxygen gun barrel; a base 12 which is fixed around the bottom of the ladle 2; and a multi-jointed arm 13 which connects the gun holding portion 11 to the base 12 and changes the position and posture of the gun holding portion 11 relative to the base 12.

[0130] Both ignition and hole opening operations can be easily accomplished with one device.

[0131] (11) The oxygen hole-opening device 8 according to (10), wherein the oxygen hole-opening device 8 further includes a force sensor 16 provided on the gun holding portion 11, and the hole-opening control portion 115 controls the conveying device 10 in a manner of inserting the top end portion into the pouring hole 3 while limiting the propulsion force of the top end portion into the pouring hole 3 based on the detection result of the force sensor 16.

[0132] It is possible to easily avoid the lining in the pouring hole 3 from being damaged due to collision with the oxygen lance tube.

[0133] (12) The oxygen opening device 8 according to (10) or (11), wherein the opening control unit 115 controls the conveying device 10 in a state where the top end portion is inserted into the casting hole 3 to a first depth so that the top end portion contacts the inner surface of the casting hole 3 at multiple locations, calculates the center position of the casting hole 3 based on the position of the top end portion when contacting the multiple locations, controls the conveying device 10 in a manner so that the center position of the top end portion is consistent with the center position of the casting hole 3, and controls the conveying device 10 in a manner so that the top end portion is inserted to a second depth deeper than the first depth.

[0134] By aligning the center position of the tip portion with the center position of the pouring hole 3 when the tip portion is inserted to the first depth, damage to the liner can be more reliably avoided until the tip portion reaches the second depth.

[0135] (13) An oxygen hole opening device 8 according to any one of (10) to (12), wherein the oxygen hole opening device 8 further comprises: a rack 44 that stores a plurality of oxygen lance tubes at a position below and away from the ladle 2; and a gun replacement control unit 118 that controls the conveying device 10 in a manner such that used oxygen lance tubes are arranged on the rack 44, and controls the conveying device 10 in a manner such that unused oxygen lance tubes stored in the rack 44 are retained in the gun retaining unit 11.

[0136] By automating the replacement of the oxygen lance tube with respect to the lance holder 11 , it is possible to further save labor in the oxygen gas drilling operation.

[0137] Description of Reference Numerals

[0138] 2. Ladle; 3. Pouring hole; 4. Gate; 5. Nozzle; 6. Tundish; 8. Oxygen opening device; 10. Conveying device; 11. Gun holding part; 12. Base; 13. Multi-joint arm; 41. Ignition device; 42. Sensor; 43. Second sensor; P11. Standby position; 16. Force sensor; 44. Rack; 20. Second conveying device; 114. Ignition control part; 115. Opening control part; 116. Position detection part; 117. Combustion detection part; 118. Gun replacement control part.

Claims

1. An oxygen opening device, wherein: The oxygen opening device has: a conveying device for conveying an oxygen lance for introducing oxygen gas so that a tip portion of the oxygen lance is positioned at a pouring hole provided at a lower portion of a ladle for molten steel and at a position heated by a heat source located at a position away from the pouring hole; a second conveying device for conveying a nozzle for guiding molten steel from the pouring hole between an installation position below the pouring hole and a retreat position retreated from the installation position; an ignition control unit configured to control the conveying device so as to place the tip portion at a position heated by the heat source and ignite the tip portion; as well as The opening control unit controls the conveying device so that the ignited tip portion is arranged in the pouring hole to open the blocked pouring hole when the second conveying device retracts the nozzle from the mounting position.

2. The oxygen opening device according to claim 1, wherein: The ignition control unit controls the conveying device so that the front end portion is positioned at a position heated by the heat source, using the molten steel stored outside the ladle as the heat source.

3. The oxygen opening device according to claim 1, wherein: The oxygen opening device further comprises an ignition device arranged around the ladle. The ignition control unit controls the conveying device so that the distal end portion is positioned at a position heated by the heat source, using the ignition device as the heat source.

4. The oxygen opening device according to any one of claims 1 to 3, wherein: A nozzle is installed below the pouring hole to guide the molten steel coming out of the pouring hole. The hole opening control unit controls the conveying device so that the ignited tip portion is positioned upward at a standby position adjacent to the nozzle, and the ignited tip portion is positioned in the pouring hole after the nozzle is removed.

5. The oxygen opening device according to any one of claims 1 to 3, wherein: The oxygen opening device further includes a clogging detection unit that detects clogging of the pouring hole based on the state of the gate opening and closing the pouring hole and the weight change of the tundish that receives the molten steel guided by the nozzle. The ignition control unit controls the conveying device so that the tip portion is positioned at the heat source after the clogging detection unit detects clogging of the pouring hole and before the second conveying device retracts the nozzle from the mounting position.

6. The oxygen opening device according to claim 5, wherein: The hole opening control unit controls the conveying device in such a manner that the ignited top end portion is directed upward and arranged in a standby position adjacent to the nozzle before the second conveying device retracts the nozzle from the installation position, and the ignited top end portion is arranged in the pouring hole after the second conveying device retracts the nozzle from the installation position.

7. The oxygen opening device according to any one of claims 1 to 3, wherein: The oxygen opening device also has: a sensor that acquires three-dimensional data of the pouring hole from outside the ladle; and a position detection unit that detects the position of the pouring hole based on the three-dimensional data acquired by the sensor, The hole opening control unit arranges the tip portion in the pouring hole based on the position of the pouring hole detected by the position detection unit.

8. The oxygen opening device according to claim 7, wherein: The oxygen opening device also has: a second sensor that acquires image data of the tip portion after ignition; and a combustion detection unit that detects whether the combustion of the tip portion is continuing based on the image data acquired by the second sensor, When the combustion detection unit detects that the combustion of the distal end portion is not continuing, the ignition control unit controls the conveying device so as to reposition the distal end portion to a position heated by the heat source.

9. The oxygen opening device according to any one of claims 1 to 3, wherein: The conveying device has: a lance holding portion that holds the oxygen lance tube; a base fixed around the bottom of the ladle; as well as A multi-joint arm connects the gun holding portion and the base portion, and changes the position and posture of the gun holding portion relative to the base portion.

10. The oxygen opening device according to claim 9, wherein: The oxygen opening device further includes a force sensor provided on the gun holding portion. The hole opening control unit controls the conveying device so as to insert the tip portion into the pouring hole while limiting the force of the tip portion propelling into the pouring hole based on the detection result of the force sensor.

11. The oxygen opening device according to claim 9, wherein: The hole opening control unit controls the conveying device so that the tip portion contacts the inner surface of the pouring hole at multiple locations when the tip portion is inserted into the pouring hole to a first depth. The hole opening control unit calculates the center position of the pouring hole based on the position of the tip portion when contacting the plurality of locations. The hole opening control unit controls the conveying device so that the center position of the top end portion coincides with the center position of the pouring hole. The opening control unit controls the delivery device so that the distal end portion is inserted to a second depth deeper than the first depth.

12. The oxygen opening device according to claim 9, wherein: The oxygen opening device also has: a rack for accommodating a plurality of oxygen lances at a position away from below the ladle; and The lance replacement control unit controls the transport device so that the used oxygen lance tubes are placed on the rack, and controls the transport device so that the unused oxygen lance tubes stored in the rack are held in the lance holding unit.

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