Submerged arc furnace laser hole burning device and method

Abstract

The invention discloses a submerged arc furnace laser hole burning device and method, and belongs to the technical field of smelting robots. The submerged arc furnace laser hole burning device comprises a high-energy laser device capable of continuously outputting, and laser generated by the high-energy laser device is transmitted to a beam shaper through an optical fiber; the beam shaper expands laser generated by the high-energy laser until the spot diameter is not smaller than one third of the required diameter of the furnace eye, the beam shaper is arranged on a multi-degree-of-freedom rotary table, and the posture of the rotary table is controlled by a control system so that the optical axis of the beam shaper can be parallel to the axis of the furnace eye. The rotary table can enable the optical axis of the beam shaper to draw a circular track with a set diameter with the axis of the furnace eye as the center, and the beam shaper is provided with a cooling system and a lens blowing mechanism. According to the invention, after laser beam expanding, energy is remotely projected to melt the hole plugging material to realize hole burning operation, so that a carbon rod contact type hole burning mode of a traditional furnace discharging robot is replaced, the production cost is reduced, and the effects of energy conservation and emission reduction are achieved.

Description

Technical Field

[0001] This invention relates to a laser burning device and method for a submerged arc furnace, belonging to the field of smelting robot technology. Background Technology

[0002] The tapping operation of submerged arc furnaces is complex and involves a harsh working environment. It mainly includes processes such as igniting the furnace eye, opening the eye, attaching fiber, cleaning the furnace tongue, repairing the eye, and plugging the eye. Among these, igniting the furnace eye is the most time-consuming part of the entire tapping process. Currently, high-temperature special-operation tapping robots are widely used in submerged arc furnaces such as calcium carbide furnaces, ferrosilicon furnaces, and industrial silicon furnaces. These robots can integrate and complete the tapping operation. Except for the furnace eye ignition process, most of the tapping steps can be automated. During the furnace eye ignition process, the tapping robot automatically holds the burn-through device and passes the carbon fiber through the front of the burn-through device. The high-temperature electric arc generated by the electric rods rapidly heats the plugging material in the furnace eye area. The feeding distance of the burner into the furnace eye needs to be remotely controlled by the operator to control the melting of the plugging material within a specified time. This semi-automatic method of using a furnace-mounted robot to burn the furnace eye not only consumes a large number of carbon rods, but also results in significant energy loss during the process of converting electrical energy into heat energy to melt the plugging material. For example, the burning time in a calcium carbide furnace is about 20 minutes, and each burning of the furnace eye using carbon rods consumes about 330 kWh of electricity. This makes the cost of burning the furnace eye very high and is also detrimental to environmental protection.

[0003] Laser radiation possesses characteristics such as high directionality, high coherence, high focusing, and high energy density. Due to its advantages of high efficiency, environmental friendliness, and precision, it is widely used in high-precision industrial processing fields such as cutting, welding, and 3D printing. In these applications, the laser is typically focused into a spot with a diameter of less than 0.3 mm to achieve high energy density, enabling the laser to generate a rapid thermal effect on the material surface. Therefore, medium-to-low energy density lasers are sufficient. This research applies the high directionality, high energy density, and high photothermal conversion efficiency of lasers to the burn-in process of submerged arc furnaces. Since submerged arc furnaces require burn-in diameters of up to 100 mm and depths of up to 1500 mm, existing laser application technologies are clearly insufficient to meet the requirements of laser burn-in, necessitating larger laser spot diameters and higher energy densities. Summary of the Invention

[0004] To address the problems of high power consumption, high cost, and severe environmental pollution caused by existing furnace-breaking robots using carbon rods for furnace eye burning, this invention proposes a laser burning device for submerged arc furnaces. It includes a continuously outputting high-energy laser. The laser beam generated by the high-energy laser is transmitted to a beam shaper via optical fiber. The beam shaper expands the laser beam to a spot diameter not less than one-third of the required furnace eye diameter. The beam shaper is mounted on a multi-degree-of-freedom turntable, whose attitude is controlled by a control system to ensure that the optical axis of the beam shaper is parallel to the axis of the furnace eye. Furthermore, the turntable allows the optical axis of the beam shaper to trace a circular trajectory of a set diameter centered on the axis of the furnace eye. The beam shaper is equipped with a cooling system to dissipate the heat generated by the beam shaper. The beam shaper also includes a lens cleaning mechanism, with its air outlet facing the external lens of the beam shaper.

[0005] The beam shaper is also equipped with an infrared thermal imager.

[0006] A beam splitter is also provided between the high-energy laser and the optical fiber. The beam splitter can sequentially switch the laser to multiple optical fibers, and the optical fibers transmit the laser to multiple sets of beam shapers. The multiple sets of beam shapers correspond to multiple furnace holes in the furnace body.

[0007] The laser burning device for a submerged arc furnace described in this invention replaces the turntable with a furnace-unloading robot.

[0008] The method using the aforementioned laser burning device for a submerged arc furnace includes the following process steps: S1 Laser beam expander: The beam shaper expands the beam output from the high-energy laser to a spot diameter not less than one-third of the required furnace eye diameter; S2 Laser Burning: The control system controls the optical axis of the beam shaper to be parallel to the axis of the furnace eye, so that the optical axis of the beam shaper draws a circular trajectory of a set diameter with the axis of the furnace eye as the center and moves at a set speed. S3 Process Monitoring: Monitors the laser burning process of the furnace eye using an infrared thermal imager.

[0009] Before the S1 laser beam expansion, the location of the furnace eye that needs to be burned through is selected. The laser output from the high-energy laser is switched to the optical fiber corresponding to the selected furnace eye through the beam distributor, and the laser is transmitted to the corresponding beam shaper by the optical fiber.

[0010] The beneficial effects of this invention are: A. By using a high-energy laser to generate a laser beam, combined with a beam shaper to expand the laser beam, and using the expanded laser radiation energy density as the energy source for burning, the plugging material absorbs the remotely projected laser radiation energy and heats up rapidly, increasing the melting rate of the plugging material. This causes the plugging material to turn into a liquid state and be discharged, thus achieving the purpose of burning. This method replaces the traditional carbon rod contact burning method used by furnace robots. The energy loss of the remotely projected laser burning method is very small. Under the same total heat energy required for burning, the power consumption of a single burning is reduced to about one-tenth of the original, which greatly reduces production costs and also achieves the effect of energy saving and emission reduction.

[0011] B. By using a beam shaper set on a multi-degree-of-freedom turntable, the position and dwell time of the laser beam irradiating the furnace eye can be automatically controlled by the control system. This facilitates automatic and precise control of the burn-in diameter and burn-in depth. The projection area of ​​the laser beam can be automatically adjusted according to factors such as the plugging material, furnace eye diameter, and furnace eye depth, thereby increasing the melting speed of the plugging material and improving work efficiency.

[0012] C. The beam shaper is equipped with a cooling system that can dissipate the heat generated by the beam shaper in a timely manner, ensuring stable long-term operation of the beam shaper, extending the service life of the equipment, and improving the reliability of this burn-in device.

[0013] D. By utilizing the lens cleaning mechanism on the beam shaper, dust that falls onto the lens outside the beam shaper can be promptly blown away during the burning process, avoiding increased energy loss due to dust blocking laser projection and preventing the equipment from burning out due to energy accumulation caused by dust obstruction, thus improving the reliability of the equipment.

[0014] E. By using the infrared thermal imager installed on the beam shaper, the laser eye burning process can be monitored in real time to generate thermal images. Based on the changes in the displayed temperature distribution, the progress of laser eye burning can be monitored in real time.

[0015] F. A beam splitter can be used to sequentially distribute the high-energy laser generated by a single laser to multiple transmission fibers, which are then used by multiple beam shapers to sequentially complete the burning process of different furnace holes on the furnace body, reducing the number of lasers and lowering equipment costs.

[0016] G. Replacing the turntable with the existing furnace-unloading robot can directly replace the traditional furnace-unloading robot's method of grabbing carbon rods and performing burn-in, realizing fully automated and integrated furnace-unloading operations and reducing the production costs of user companies. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the present invention.

[0018] Figure 2This is a schematic diagram of a large-diameter furnace eye created by a small-diameter light spot. Detailed Implementation

[0019] To make the objectives, technical solutions, and beneficial effects of the present invention clearer, the embodiments of the present invention are described in detail below with reference to the accompanying drawings. The embodiments are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0020] See Figures 1-2 The first embodiment of the present invention proposes a laser burning device for a submerged arc furnace, which includes a high-energy laser 1 capable of continuous output. The laser generated by the high-energy laser 1 is transmitted to a beam shaper 4 through an optical fiber 2. The beam shaper 4 expands the laser generated by the high-energy laser 1 to a beam diameter not less than one-third of the required furnace eye diameter. The beam shaper 4 is mounted on a multi-degree-of-freedom turntable 3. The turntable 3 is controlled by a control system to make the optical axis of the beam shaper 4 parallel to the axis of the furnace eye 6. The turntable 3 can also make the optical axis of the beam shaper 4 draw a circular trajectory of a set diameter with the axis of the furnace eye 6 as the center. The beam shaper 4 is equipped with a cooling system 9, which can dissipate the heat generated by the beam shaper 4. The beam shaper 4 is also equipped with a lens blowing mechanism 7, the air outlet of which faces the external lens of the beam shaper 4.

[0021] Furthermore, the beam shaper 4 is also equipped with an infrared thermal imager 8, which can monitor the burning process in real time and generate thermal images. Based on the changes in the displayed temperature distribution, the progress of laser burning can be monitored in real time.

[0022] Specifically, the high-energy laser 1 refers to a laser device with a continuous output power exceeding 1.5 kilowatts, which emits high-energy-density laser light that can cause a phase change in the furnace eye material, transforming it from a solid state to a liquid state. The high-energy laser 1 is preferably a fiber laser. Currently, the highest output power fiber lasers available on the market are 100kW-level, and with future technological advancements, lasers with even higher output power can be configured.

[0023] In one embodiment of the present invention, the diameter of the furnace eye at the outlet of the calcium carbide furnace is 50 mm and the depth of the furnace eye is 1000 mm. The selected high-energy laser 1 is configured as a fiber laser with a maximum output power of 100 kW. In use, a continuous output power of 88 kW is adopted. The specific process steps include the following: S1 Laser beam expansion: Select the furnace eye 6 that needs to be burned through, and switch the laser output from the high-energy laser 1 to the fiber 2 corresponding to the selected furnace eye through the beam distributor. The fiber 2 transmits the laser to the corresponding beam shaper 4, and the beam shaper 4 expands the beam output from the high-energy laser 1 to a spot diameter of 50mm. S2 Laser Burning: The control system controls the optical axis of the beam shaper 4 to be parallel to the axis of the furnace eye 6. After 4.5 minutes of continuous burning, the heat energy converted by the laser will convert the solid plugging material with a depth of 1000mm into liquid and discharge it completely. S3 Process Monitoring: The process of laser burning the furnace eye is monitored by infrared thermal imager 8.

[0024] The power consumption for this laser beam burning process is 6.6 kWh (6.6 kWh). During the burning process, the cooling system 9 can dissipate the heat generated by the beam shaper 4 in a timely manner. The lens cleaning mechanism 7 continuously cleans the external lens of the beam shaper 4 during the laser beam burning process to prevent dust from falling on the lens and blocking the laser beam projection. The turntable 3 adopts an articulated structure. A dust removal and ventilation system is set in the projection area of ​​the high-energy laser 1 to further reduce energy loss during laser projection.

[0025] The second embodiment of the present invention, based on the first embodiment, further includes a beam splitter between the high-energy laser 1 and the optical fiber 2. The beam splitter can sequentially switch the laser to multiple optical fibers 2, and the optical fibers 2 transmit the laser to multiple sets of beam shapers 4. The multiple sets of beam shapers 4 correspond to multiple furnace holes 6 of the furnace body 5. When one of the furnace holes 6 is locked for this furnace firing, the corresponding burning work can be completed by one set of beam shapers 4.

[0026] The third embodiment of the present invention replaces the turntable 3 with a furnace exit robot based on the first embodiment, realizing integrated furnace exit operation. Through the beam shaper 4 set on the furnace exit robot, the furnace exit robot can move the beam shaper 4 according to the actual furnace exit requirements of each furnace eye 6 on the furnace body 5, adjust the relative position of the laser beam and the furnace eye 6, and perform the burning operation of the corresponding furnace eye 6.

[0027] The fourth embodiment of the present invention, based on the second embodiment, replaces the turntable 3 with a furnace exit robot. The laser is sequentially switched to multiple optical fibers 2 by a beam distributor, and the laser is transmitted to multiple sets of beam shapers 4 by the optical fibers 2. Each set of beam shapers 4 is equipped with a furnace exit robot. The multiple furnace exit robots make the beam shapers 4 correspond to multiple furnace holes 6 of the furnace body 5 respectively. When one of the furnace holes 6 is locked, the corresponding furnace exit robot can be operated to drive the beam shaper 4 to complete the corresponding burning work.

Claims

1. A laser ablation device for a submerged arc furnace, comprising a continuously outputting high-energy laser (1), characterized in that: The laser generated by the high-energy laser (1) is transmitted to the beam shaper (4) through the optical fiber (2). The beam shaper (4) expands the laser generated by the high-energy laser (1) to a beam diameter not less than one-third of the required furnace eye diameter. The beam shaper (4) is set on a multi-degree-of-freedom turntable (3). The turntable (3) is controlled by the control system to make the optical axis of the beam shaper (4) parallel to the axis of the furnace eye (6). The turntable (3) can make the optical axis of the beam shaper (4) draw a circular trajectory of a set diameter with the axis of the furnace eye (6) as the center. The beam shaper (4) is equipped with a cooling system (9). The cooling system (9) can dissipate the heat generated by the beam shaper (4). The beam shaper (4) is also equipped with a lens cleaning mechanism (7). The air outlet of the lens cleaning mechanism (7) faces the external lens of the beam shaper (4).

2. The laser burning device for a submerged arc furnace according to claim 1, characterized in that: The beam shaper (4) is also equipped with an infrared thermal imager (8).

3. The laser burning device for a submerged arc furnace according to claim 1, characterized in that: A beam splitter is also provided between the high-energy laser (1) and the optical fiber (2). The beam splitter can sequentially switch the laser to multiple optical fibers (2), and the optical fibers (2) transmit the laser to multiple sets of beam shapers (4). The multiple sets of beam shapers (4) correspond to multiple furnace holes (6) of the furnace body (5).

4. The laser burning device for a submerged arc furnace according to any one of claims 1-3, characterized in that: The turntable (3) is replaced by a furnace exit robot.

5. A method for laser ablation of an anode in a submerged arc furnace performed using the apparatus according to any one of claims 1-4, comprising the following process steps: S1 Laser beam expander: The beam shaper (4) expands the beam output from the high-energy laser (1) to a beam diameter not less than one-third the diameter of the required furnace eye (6); S2 Laser eye burning: The control system controls the optical axis of the beam shaper (4) to be parallel to the axis of the furnace eye (6), so that the optical axis of the beam shaper (4) draws a circular trajectory of a set diameter with the axis of the furnace eye (6) as the center and according to the set movement speed. S3 Process monitoring: The process of laser burning the furnace eye is monitored by an infrared thermal imager (8).

6. The laser ablation method for a submerged arc furnace according to claim 5, characterized in that: Before the S1 laser beam expansion, the location of the furnace eye (6) to be burned through is selected, and the laser output from the high-energy laser (1) is switched to the optical fiber (2) corresponding to the selected furnace eye through the beam distributor. The laser is then transmitted to the corresponding beam shaper (4) by the optical fiber (2).

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