Device and method for improving steel ladle refining calcium treatment yield

Abstract

The invention discloses a device and a method for improving the calcium treatment yield in ladle refining. The device comprises a wire feeder, a walking vehicle, a lifting part, a limiting part, a rotating part and a wire control part, the wire feeding machine and the walking vehicle are arranged on the ground; the lifting part is arranged on the walking vehicle; the limiting part and the rotating part are arranged on the lifting part; and the wire control part is arranged on the rotating part. According to the method, the refined calcium treatment yield is effectively improved.

Description

Technical Field

[0001] The invention relates to a device and method for improving the calcium treatment yield of ladle refining, in particular to a device and method capable of improving the calcium treatment yield when calcium wire is put in, belonging to the technical field of calcium wire putting equipment for ladle refining. Background Art

[0002] Calcium treatment is a process of feeding calcium wire into molten steel for treatment. Its main purpose is to remove MnS inclusions and Al 2 O 3 The inclusions are denatured to reduce the number of inclusions, change their composition and properties, and thus purify the molten steel; but due to the characteristics of calcium such as high activity, low melting and boiling points, high vapor pressure, and low solubility of calcium in molten steel, it is easy to cause low calcium yield or unstable yield; At present, the research on improving the calcium wire yield of LF furnace is mainly focused on the calcium wire feeding equipment and the process before controlling calcium treatment, such as the patent application with publication number CN107022668A "A wire feeding device and method for improving the calcium alloy yield in steelmaking process", which is mainly aimed at the transformation of calcium feeding line equipment; the patent application with publication number CN111471826A "A process control method for improving the calcium wire yield of LF furnace" and the patent application with publication number CN116555519 A's patent application "A treatment method for improving the yield of refined calcium treatment" ensures the content of FeO+MnO in the slag by reducing the oxidizability of the slag before wire feeding. However, in the actual production process, the FeO+MnO content in the slag needs to go through a series of sample preparation and testing to obtain the result, which takes a long time and cannot be used directly to determine the oxidizability of the slag. It can be seen that the existing technology is not sufficient for research on improving the yield of calcium wire. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a device and method for improving the calcium treatment yield of ladle refining, which can effectively improve the value of the calcium treatment yield.

[0004] The problem described in the present invention is solved by the following technical solutions: A device for improving the recovery rate of calcium treatment in ladle refining comprises a wire feeding machine, a traveling vehicle, a lifting part, a limiting part, a rotating part and a wire control part; the wire feeding machine and the traveling vehicle are both arranged on the ground; the lifting part is arranged on the traveling vehicle; the limiting part and the rotating part are both arranged on the lifting part; and the wire control part is arranged on the rotating part.

[0005] The above-mentioned device for improving the recovery rate of calcium treatment in ladle refining, the lifting part includes a vertical plate, a winch, a first slide plate and a lifting horizontal plate; the vertical plate is arranged on the side wall of the traveling vehicle; a support plate is arranged at the top of the vertical plate, and the winch is arranged on the support plate; the side wall of the vertical plate is provided with a slide rail along the vertical direction, and the first slide plate is slidably arranged on the slide rail; the lifting horizontal plate is arranged on the first slide plate; the end of the winch rope is connected to the lifting horizontal plate; the side wall of the vertical plate is provided with scales along the vertical direction, and the side wall of the lifting horizontal plate is provided with a pointing plate, and the pointing plate corresponds to the scale position on the side wall of the vertical plate.

[0006] The above-mentioned device for improving the recovery rate of calcium treatment in ladle refining, the rotating part includes a limit ring, a disc, a first motor and a driving gear; the limit ring is arranged on the lifting horizontal plate; the upper end surface of the limit ring is provided with a circle of limit grooves, the bottom end surface of the disc is provided with a circle of limit strips, and the limit strips at the bottom end of the disc are slidably arranged in the limit grooves of the limit ring; the first motor is arranged at the edge of the upper end surface of the limit ring through a bracket, and the end of its output shaft is provided with a driving gear; a circle of teeth is provided on the circumferential side wall of the disc, and the teeth of the driving gear are meshed and transmission-connected with the teeth on the side wall of the disc.

[0007] The above-mentioned device for improving the recovery rate of calcium treatment in ladle refining, the limiting part includes a horizontal guide rod, a sliding rod, a U-shaped plate, a rotating plate and a limiting mechanism; the horizontal guide rod is set on the lifting horizontal plate through a bracket, and a guide hole is set at its end; the sliding rod is inserted into the guide hole at the end of the horizontal guide rod; the U-shaped plate is set at the end of the sliding rod; the center of the rotating plate is axially connected to the inner wall of the U-shaped plate through a rotating shaft, and the axis of the rotating shaft is a vertical direction line; the number of the limiting mechanisms is two, and they are both set on the rotating plate.

[0008] The above-mentioned device for improving the recovery rate of calcium treatment in ladle refining, the limiting mechanism includes a slider, a vertical round rod, a lower long rod and an upper long rod; the end surface of the rotating plate away from the sliding rod is provided with a sliding groove, and the slider is slidably arranged in the sliding groove of the rotating plate; the vertical round rod is arranged on the top surface of the slider; the ends of the lower long rod and the upper long rod are both provided with insertion holes, and the insertion holes at the ends of the lower long rod and the upper long plate are both passed through by the vertical round rod.

[0009] The above-mentioned device for improving the recovery rate of calcium treatment in ladle refining, the wire control part includes a transverse movement mechanism and a wire release mechanism; the transverse movement mechanism is arranged on the disc, and the wire release mechanism is arranged on the transverse movement mechanism.

[0010] The above-mentioned device for improving the recovery rate of calcium treatment in ladle refining, the transverse movement mechanism includes a second motor, a screw, a screw nut and a second slide plate; the upper end surface of the disc is provided with a strip hole along the diameter direction, and the length of the strip hole is equal to the radius of the disc; the second motor and the support plate are both arranged on the upper end surface of the disc, and are respectively located at the two ends of the strip hole; one end of the screw is connected to the output shaft of the second motor, and the other end of the screw is connected to the support plate axis; the screw nut is arranged on the screw; the second slide plate is slidably arranged in the strip hole of the disc, and the screw nut is connected to the second slide plate.

[0011] The above-mentioned device for improving the recovery rate of calcium treatment in ladle refining, the wire-releasing mechanism includes a bent pipe, a vertical hollow pipe and a high-temperature resistant pipe; the second slide plate is provided with a vertical hole, and the vertical hollow pipe is arranged in the vertical hole; the high-temperature resistant pipe is arranged at the bottom end of the vertical hollow pipe, and the bottom end hole of the vertical hollow pipe is connected with the top end hole of the high-temperature resistant pipe; a joint is provided at the top end of the side wall of the high-temperature resistant pipe, and the joint is connected to the inner cavity of the high-temperature resistant pipe; a circle of sliding grooves is provided at the top end of the inner wall of the vertical hollow pipe, a circle of sliding strips is provided at the end of the outer wall of the bent pipe, and the sliding strips on the outer wall of the bent pipe are slidably arranged in the sliding grooves at the top end of the inner wall of the vertical hollow pipe.

[0012] In the above device for improving the recovery rate of calcium treatment in ladle refining, the calcium wire enters the molten steel in the ladle after passing through the wire feeding machine, the elbow, the vertical hollow tube and the high-temperature resistant tube in sequence.

[0013] A method for improving the yield of ladle refining calcium treatment, comprising the following steps: Step 1: Adjust the slag of the ladle. According to the condition of the slag, add aluminum powder, lime, refined slag, etc. to adjust the slag. The Alt content of the molten steel before feeding the calcium line is required to be controlled at 0.020%-0.040%, the S content is ≤0.012%, and the temperature T is controlled at 1620-1630℃; Take a sample after the slag is adjusted, and then take a sample again after an interval of 3 minutes. The oxidizability of the molten steel is determined by analyzing the full composition of the steel. The specific determination is: ∆Alt=Alt 1 -Alt 2 ≤0.002%, ∆Si=Si 2 -Si 1 ≥0.005%; In the formula, ∆Alt and ∆Si are the differences between the components analyzed in two samplings; Alt 1 、Si 1 Analyze the composition value for the first sampling; Alt 2 、Si 2 Analyze the composition values ​​for the second sampling; When it is determined that the requirements are met, it can be determined that the molten steel is in a weakly oxidizing or reducing state, and the calcium wire can be added; Step 2: Push the traveler to move in front of the ladle, and adjust the position of the traveler so that the axis of the disc coincides with the central axis of the ladle; if the ladle has a single argon blowing hole at the bottom, and control a limit mechanism to move, drive a slider to move to the top of the bottom argon blowing hole, and then swing the lower long rod and the upper long rod, the two long rods are 15 degrees apart from the connecting line of the slider and the center point of the disc in different directions; the area between the upper long rod and the lower long plate is a fan-shaped area, and the subsequent pay-off mechanism position needs to be adjusted to the fan-shaped area between the upper long rod and the lower long plate; If there are two argon blowing holes at the bottom of the ladle, the two sliders are controlled to move to the top of the two argon blowing holes respectively, and then the upper long rod on one slider is controlled to move, and the lower long rod on the other slider is controlled to move, and the two moving long rods are made to pass through the axis of the disc. At this time, the fan-shaped area of ​​the angle between the lower long rod and the upper long rod is the position range of the subsequent wire release mechanism; Step 3: Adjust the position of the pay-off mechanism so that it falls into the specified sector area; the first motor drives the disc to rotate, and the second motor drives the second slide plate to slide, and the two cooperate to adjust the position of the direction mechanism so that the pay-off mechanism falls into the specified sector area, and then fine-tune the position of the pay-off mechanism so that the minimum distance between the high temperature resistant tube and the inner wall of the ladle is within the range of 0.3 to 0.5 times the inner diameter of the ladle; Step 4: Control the action of the winch to drive the lifting horizontal plate downward, and drive the rest of the parts set on the lifting horizontal plate to move downward synchronously; until the bottom end of the high-temperature resistant tube contacts the slag, and then according to the scales on the winch and the side wall of the vertical plate, the bottom end of the high-temperature resistant tube is moved into the molten steel, and it is ensured that the insertion depth of the bottom end of the high-temperature resistant tube is greater than 300mm, and the distance between the bottom end and the bottom end of the ladle is greater than 1000mm.

[0014] Step 5: Before wire feeding, the argon flow rate of the ladle bottom is 300L / min-500L / min; when feeding the wire, the argon flow rate of the ladle bottom is 100L / min-200L / min; when feeding the wire, the joint at the top of the high-temperature resistant tube is connected to the argon source, and the argon flow rate in the high-temperature resistant tube is 100L / min-200L / min; when feeding the wire, the calcium wire passes through the wire feeding machine, the elbow, the vertical hollow tube and the high-temperature resistant tube in turn and enters the molten steel in the ladle; after the wire feeding is completed, remove this device and the ladle returns to the normal argon blowing state.

[0015] The present invention provides a device and method for improving the yield of ladle refining calcium treatment, so that the composition of molten steel is properly controlled before feeding the calcium wire, and the oxidizability of the molten steel is indirectly characterized by the change of the composition of the molten steel, and the wire is fed when the oxidizability of the molten steel reaches a certain level, thereby avoiding the problem that the oxidizability of the molten steel is difficult to judge and the calcium wire oxidation yield is low; at the same time, by adjusting the position of the wire control part, the operation of the wire control part and argon blowing, the calcium wire is in contact with the molten steel in the middle of the molten steel, thereby avoiding the situation that the yield is unstable due to the low solubility of calcium in the molten steel. It has a good effect on improving the calcium wire yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall three-dimensional structure of the present invention; Figure 2 It is a schematic diagram of a partially enlarged structure of A of the present invention; Figure 3 It is a schematic diagram of the elevation angle stereo structure of the present invention; Figure 4 It is the limiting area of ​​the high temperature resistant tube when the bottom blowing hole of the ladle is a single hole; Figure 5 It is the limiting area of ​​the high temperature resistant tube when the bottom blowing hole of the ladle is a double hole.

[0017] The list of numbers in the figure is: 1. Traveling vehicle, 2. Vertical plate, 3. Winch, 4. First slide plate, 5. Lifting horizontal plate, 6. Limiting ring, 7. Disc, 8. First motor, 9. Horizontal guide rod, 10. U-shaped plate, 11. Rotating plate, 12. Slider, 13. Vertical round rod, 14. Lower long rod, 15. Upper long rod, 16. Second motor, 17. Screw nut, 18. Second slide plate, 19. Bend pipe, 20. Vertical hollow pipe, 21. High temperature resistant pipe. DETAILED DESCRIPTION

[0018] See also Figure 1 , 2 , 3, 4 and Figure 5 The present invention includes a wire feeding machine, a traveling vehicle 1, a lifting part, a limiting part, a rotating part and a wire control part; the wire feeding machine is a common wire feeding device at present, which can directly feed the wire; the wire feeding machine and the traveling vehicle 1 are both arranged on the ground; the lifting part is arranged on the traveling vehicle 1; the lifting part can control the wire-laying depth of the wire control part; the limiting part and the rotating part are both arranged on the lifting part; the limiting part is used to plan the wire-laying position and the high-temperature resistant tube argon blowing position; the wire control part is arranged on the rotating part; the wire control part is used to control the wire-laying depth and position.

[0019] The lifting part includes a vertical plate 2, a winch 3, a first slide plate 4 and a lifting horizontal plate 5; the vertical plate 2 is arranged on the side wall of the traveling vehicle 1; a support plate is arranged at the top of the vertical plate 2, and the winch 3 is arranged on the support plate; the side wall of the vertical plate 2 is provided with a slide rail along the vertical direction, and the first slide plate 4 is slidably arranged on the slide rail; the lifting horizontal plate 5 is arranged on the first slide plate 4; the first slide plate 4 can slide on the vertical plate 2 through the slide rail; the winch 3 can drive the lifting horizontal plate 5 to rise and fall vertically, thereby controlling the depth of the high-temperature resistant pipe in the molten steel; the end of the pull rope of the winch 3 is connected to the lifting horizontal plate 5; the side wall of the vertical plate 2 is provided with a scale along the vertical direction, and the side wall of the lifting horizontal plate 5 is provided with a pointing plate, and the pointing plate corresponds to the scale position on the side wall of the vertical plate 2; the insertion depth of the high-temperature resistant pipe can be accurately controlled through the scale.

[0020] The rotating part includes a limit ring 6, a disc 7, a first motor 8 and a driving gear; the limit ring 6 is arranged on the lifting horizontal plate 5; the upper end face of the limit ring 6 is provided with a circle of limit grooves, the bottom end face of the disc 7 is provided with a circle of limit strips, and the limit strips at the bottom end of the disc 7 are slidably arranged in the limit grooves of the limit ring 6; the disc 7 can rotate in situ on the limit ring 6; the first motor 8 is arranged at the edge of the upper end face of the limit ring 6 through a bracket, and a driving gear is arranged at the end of its output shaft; a circle of teeth is arranged on the circumferential side wall of the disc 7, and the teeth of the driving gear are meshed and connected with the teeth on the side wall of the disc 7; the first motor 8 can drive the driving gear to rotate, thereby driving the teeth on the disc to follow, and finally driving the disc 7 to rotate.

[0021] The limiting part includes a horizontal guide rod 9, a sliding rod, a U-shaped plate 10, a rotating plate 11 and a limiting mechanism; the horizontal guide rod 9 is arranged on the lifting horizontal plate 5 through a bracket, and a guide hole is arranged at its end; the sliding rod is inserted into the guide hole at the end of the horizontal guide rod 9; the sliding rod can slide out of the horizontal guide rod 9, thereby extending its total length; the U-shaped plate 10 is arranged at the end of the sliding rod; the center of the rotating plate 11 is axially connected to the inner wall of the U-shaped plate 10 through a rotating shaft, and the axis line of the rotating shaft is a vertical direction line; through the sliding of the sliding rod, the rotating plate 11 can be axially connected in the U-shaped plate 10, so that the slider 12 can be moved to the specified point, ensuring that the slider 12 can be moved to the top of the specified bottom blowing argon hole; the number of the limiting mechanisms is two, and they are both arranged on the rotating plate 11; when there is only one bottom blowing hole at the bottom of the ladle, only one limiting mechanism is needed, and if there are two bottom blowing holes, two limiting mechanisms need to be put into use.

[0022] The limiting mechanism includes a slider 12, a vertical round rod 13, a lower long rod 14 and an upper long rod 15; a sliding groove is provided on the end surface of the rotary plate 11 away from the sliding rod, and the slider 12 is slidably arranged in the sliding groove of the rotary plate 11; the slider 12 can slide on the rotary plate 11 to adjust its position; the vertical round rod 13 is arranged on the top surface of the slider 12; the ends of the lower long rod 14 and the upper long rod 15 are both provided with insertion holes, and the insertion holes at the ends of the lower long rod 14 and the upper long plate are both passed through by the vertical round rod 13; the long rod can rotate on the vertical round rod 13 to define the position of the line-releasing mechanism.

[0023] The line control part includes a transverse movement mechanism and a line-releasing mechanism; the transverse movement mechanism is arranged on the disc 7, and the line-releasing mechanism is arranged on the transverse movement mechanism; the transverse movement mechanism can adjust the position of the line-releasing mechanism.

[0024] The transverse movement mechanism includes a second motor 16, a lead screw, a lead screw nut 17 and a second slide plate 18; the upper end surface of the disk 7 is provided with a strip hole along the diameter direction, and the length of the strip hole is equal to the radius of the disk 7; the second slide plate 18 can slide on the strip hole to adjust the position of the wire-releasing mechanism; the second motor 16 and the support plate are both arranged on the upper end surface of the disk 7, and are respectively located at the two ends of the strip hole; one end of the lead screw is connected to the output shaft of the second motor 16, and the other end of the lead screw is connected to the support plate axis; the second motor 16 can drive the lead screw to rotate, and then drive the lead screw nut to move along the lead screw; the lead screw nut 17 is arranged on the lead screw; the second slide plate 18 is slidably arranged in the strip hole of the disk 7, and the lead screw nut 17 is connected to the second slide plate 18; when the lead screw nut is driven to move, it drives the second slide plate 18 to slide synchronously.

[0025] The wire-releasing mechanism includes a curved tube 19, a vertical hollow tube 20 and a high-temperature resistant tube 21; a vertical hole is provided on the second slide plate 18, and the vertical hollow tube 20 is provided in the vertical hole; the high-temperature resistant tube 21 is provided at the bottom end of the vertical hollow tube 20, and the bottom end hole of the vertical hollow tube is connected to the top end hole of the high-temperature resistant tube 21; a joint is provided at the top end of the side wall of the high-temperature resistant tube 21, and the joint is connected to the inner cavity of the high-temperature resistant tube 21, and this joint is used to pass argon gas; a circle of sliding grooves is provided at the top end of the inner wall of the vertical hollow tube 20, and a circle of sliding strips is provided at the end of the outer wall of the curved tube 19, and the sliding strips on the outer wall of the curved tube 19 are slidably provided in the sliding grooves at the top end of the inner wall of the vertical hollow tube 20; the curved tube 19 can be rotated at the top end of the vertical hollow tube 20 to change the receiving orientation, thereby facilitating it to receive the calcium wire from the wire feeding machine.

[0026] The calcium wire passes through the wire feeding machine, the curved pipe 19, the vertical hollow pipe 20 and the high temperature resistant pipe 21 in sequence and then enters into the molten steel in the ladle.

[0027] The present invention comprises the following steps: Step 1: Adjust the slag of the ladle. According to the condition of the slag, add aluminum powder, lime, refined slag, etc. to adjust the slag. The Alt content of the molten steel before feeding the calcium line is required to be controlled at 0.020%-0.040%, the S content is ≤0.012%, and the temperature T is controlled at 1620-1630℃; The reason for adjusting the slag is that deep desulfurization can only be carried out after the molten steel is deoxidized, and aluminum, as a strong deoxidizer, can effectively remove oxygen from the molten steel. However, since aluminum will be oxidized during the refining process, the Alt content of the molten steel is controlled at 0.020-0.040wt% before this treatment to ensure the low oxidation of the molten steel before calcium treatment and the completion of the desulfurization task; practice shows that when the S content in the molten steel is not more than 0.012%, adding calcium wire will not produce a large amount of CaS and reduce the yield of calcium wire; the temperature of 1620-1630℃ is mainly to ensure the outlet temperature of the molten steel after the calcium treatment process is completed; Take a sample after the slag is adjusted, and then take a sample again after an interval of 3 minutes. The oxidizability of the molten steel is determined by analyzing the full composition of the steel. The specific determination is: ∆Alt=Alt 1 -Alt 2 ≤0.002%, ∆Si=Si 2 -Si 1 ≥0.005%; In the formula, ∆Alt and ∆Si are the differences between the components analyzed in two samplings; Alt 1 、Si 1 Analyze the composition value for the first sampling; Alt 2 、Si 2 Analyze the composition values ​​for the second sampling; When it is determined that the requirements are met, it can be determined that the molten steel is in a weakly oxidizing or reducing state, and the calcium wire can be added; The main purpose of sampling is to determine the chemical composition changes caused by the changes in the oxidation of molten steel. Based on long-term exploration and repeated experiments, it was concluded that the composition of two samples taken three minutes apart is ∆Alt=Alt. 1 -Alt 2 ≤0.002%, ∆Si=Si 2 -Si 1 ≥0.005%; This is because during the refining process, the oxidizing property of the molten steel continuously oxidizes the aluminum content. When the aluminum content no longer shows a downward trend, it means that the oxidizing property of the molten steel has been controlled; when the molten steel is weakly oxidizing or reducing, the SiO in the slag 2 Will be reduced, so that Si element enters the steel, increasing the Si content in the steel. 2 -Si 1 ≥0.005%, it can be determined that the molten steel is in a weakly oxidizing or reducing state.

[0028] Step 2: Push the traveler 1 to move in front of the ladle, and adjust the position of the traveler 1 so that the axis of the disc 7 coincides with the central axis of the ladle; if the ladle has a single argon blowing hole at the bottom, and control a limit mechanism to move, drive a slider 12 to move to the position just above the bottom argon blowing hole, and then swing the lower long rod 14 and the upper long rod 15, the two long rods are fifteen degrees apart from the connecting line of the slider 12 and the center point of the disc 7 in different directions; the area between the upper long rod 15 and the lower long plate is a fan-shaped area, and the subsequent position of the pay-off mechanism needs to be adjusted to the fan-shaped area between the upper long rod 15 and the lower long plate; If there are two argon blowing holes at the bottom of the ladle, the two sliders 12 are controlled to move to the top of the two argon blowing holes respectively, and then the upper long rod 15 on one slider 12 is controlled to move, and the lower long rod 14 on the other slider 12 is controlled to move, and the two moving long rods are made to pass through the axis of the disk 7. At this time, the fan-shaped area of ​​the angle between the lower long rod 14 and the upper long rod 15 is the position range of the subsequent wire release mechanism; Step 3: Adjust the position of the pay-off mechanism so that it falls into the specified sector-shaped area; the first motor 8 drives the disc 7 to rotate, and the second motor 16 drives the second slide plate 18 to slide, and the two cooperate to adjust the position of the direction mechanism so that the pay-off mechanism falls into the specified sector-shaped area, and then fine-tune the position of the pay-off mechanism so that the minimum distance between the high-temperature resistant tube 21 and the inner wall of the ladle is within the range of 0.3 to 0.5 times the inner diameter of the ladle; Step 4: Control the action of the winch 3 to drive the lifting horizontal plate 5 downward, and drive the rest of the parts arranged on the lifting horizontal plate 5 to move downward synchronously; until the bottom end of the high temperature resistant tube 21 contacts the steel slag, and then according to the winch 3 and the scales on the side wall of the vertical plate 2, the bottom end of the high temperature resistant tube 21 is moved into the molten steel, and it is ensured that the insertion depth of the bottom end of the high temperature resistant tube 21 is greater than 300mm, and the distance between the bottom end and the bottom end of the ladle is greater than 1000mm. The insertion depth is controlled because if the distance from the slag layer is close, the molten steel will be exposed to oxidation due to the reaction when feeding the calcium wire. It should not be too close to the bottom of the ladle, mainly considering the melting of the calcium wire and not letting the calcium be in the dead zone at the bottom of the molten steel flow field, so that the calcium can be more evenly absorbed by the molten steel under the action of the flow field; Step 5: Before wire feeding, the argon flow rate of the ladle bottom is 300L / min-500L / min; when feeding the wire, the argon flow rate of the ladle bottom is 100L / min-200L / min; when feeding the wire, the joint at the top of the high temperature resistant tube 21 is connected to the argon source, and the argon flow rate in the high temperature resistant tube 21 is 100L / min-200L / min; the purpose of the high temperature resistant tube 21 participating in argon blowing is to prevent the molten steel from entering the high temperature resistant tube 21, and to blow argon to form a circulation to drive calcium absorption; when wire feeding starts, the calcium wire passes through the wire feeding machine, the elbow 19, the vertical hollow tube 20 and the high temperature resistant tube 21 in turn and then enters the molten steel in the ladle; after wire feeding is completed, the device is removed and the ladle returns to normal argon blowing state. Example 1

[0029] When smelting SPHC steel, after the molten steel enters the station, the electrode is inserted into the ladle and the electricity is turned on to increase the temperature. During the heating process, slag-making materials, lime, aluminum chips, etc. are added to adjust the slag. After the heating is completed, the temperature of the molten steel is 1630℃, and the refined slag is observed to be white; The chemical composition of the molten steel was tested by sampling. The steel contained C: 0.045%, Mn: 0.20%, S: 0.010%, P: 0.018%, Si: 0.02%, Alt: 0.035%. The molten steel met the requirements of the calcium feeding line. After an interval of three minutes, the chemical composition was tested again. The steel contained C: 0.045%, Mn: 0.20%, S: 0.009%, P: 0.018%, Si: 0.025%, Alt: 0.034%; Determine the oxidizability of molten steel ∆Alt=Alt 1 -Alt 2 =0.035%-0.034%=0.001%<0.002%, ΔSi=Si 2 -Si 1 =0.025%-0.02%=0.005%; the composition difference between the two samples meets the requirements.

[0030] The ladle is single-hole bottom blowing, and the flow rate of bottom blowing argon is reduced from 500L / min to 200L / min. According to the position of the bottom blowing hole, the position of the high-temperature resistant tube is within the range of ±15° of the line connecting the bottom blowing hole and the center of the bottom circle of the ladle. The distance between the position of the high-temperature resistant tube and the ladle wall is adjusted to 0.5R. The high-temperature resistant tube is inserted into the molten steel, and the depth is 800mm from the refining slag layer. At the same time, argon is passed into the high-temperature resistant tube, and the argon flow rate is 100L / min; then the calcium wire is added, and the amount of calcium wire added is 200m. After the wire feeding is completed, the wire feeding device is removed; After blowing argon for 8 minutes, samples were taken to test the composition of the molten steel. C: 0.045%, Mn: 0.20%, S: 0.006%, P: 0.018%, Si: 0.028%, Alt: 0.034%, Ca: 0.0030%, Calculate the calcium recovery rate: the weight of molten steel is 90t, the calcium content of each meter of calcium wire is 60g, the purity of calcium wire is 98%, and the recovery rate of calcium wire is 28.34%. Example 2

[0031] To smelt MRT2.5 steel, after the molten steel enters the station, the electrode is inserted into the ladle and the electricity is turned on to heat it up. During the heating process, slag-making materials, lime, aluminum chips, etc. are added to adjust the slag. After the heating is completed, the temperature of the molten steel is 1630℃, and the refined slag is observed to be white; Sampling to test the chemical composition of molten steel, C: 0.045%, Mn: 0.25%, S: 0.010%, P: 0.015%, Si: 0.015%, Alt: 0.030%, molten steel meets the requirements of calcium feeding line. After an interval of three minutes, sampling again to test the chemical composition, C: 0.045%, Mn: 0.25%, S: 0.009%, P: 0.016%, Si: 0.025%, Alt: 0.032%; Determine the oxidizability of molten steel ∆Alt=Alt 1 -Alt 2 =0.030%-0.032%=-0.002%<0.002%, ΔSi=Si 2 -Si 1 =0.025%-0.015%= 0.01%>0.005%. The composition difference between the two samples meets the requirements; The ladle is double-hole bottom blowing, and the flow rate of bottom blowing argon is reduced from 500L / min to 200L / min. According to the position of the bottom blowing hole, the high temperature resistant tube is located in the fan-shaped area between the center of the two bottom blowing holes and the extension line of the line connecting the center of the bottom circle of the ladle. The distance between the position of the high temperature resistant tube and the ladle wall is adjusted to 0.5R. The high temperature resistant tube is inserted into the molten steel, and the depth is 800mm from the refined slag layer. At the same time, argon is passed into the high temperature resistant tube, and the argon flow rate is 100L / min. Then the calcium wire is added, and the amount of calcium wire added is 200m. After the wire feeding is completed, the wire feeding device is removed; After blowing argon for 8 minutes, samples were taken to detect the composition of the molten steel. C: 0.045%, Mn: 0.25%, S: 0.006%, P: 0.016%, Si: 0.028%, Alt: 0.032%, Ca: 0.0033%; Calculate the calcium recovery rate: the weight of molten steel is 90t, the calcium content of each meter of calcium wire is 60g, and the purity of calcium wire is 98%, then the calcium wire recovery rate is 31.18%.

[0032] Comparative Example 1 When smelting SPHC steel, after the molten steel enters the station, the electrode is inserted into the ladle and the electricity is turned on to heat it up. During the heating process, slag-making materials, lime, aluminum chips, etc. are added to adjust the slag. After the heating is completed, the temperature of the molten steel is 1630℃, and the refined slag is observed to be white.

[0033] Sampling was taken to test the chemical composition of the molten steel, showing C: 0.045%, Mn: 0.20%, S: 0.010%, P: 0.015%, Si: 0.015%, and Alt: 0.030%.

[0034] The ladle is a single-hole bottom blowing ladle. The flow rate of the bottom blowing argon gas is reduced from 500L / min to 200L / min. The wire feeding position is just above the bottom blowing hole. The amount of calcium wire added is 200m. After the wire feeding is completed, the wire feeding device is removed.

[0035] After blowing argon for 8 minutes, take a sample to test the composition of the molten steel. C: 0.045%, Mn: 0.20%, S: 0.006%, P: 0.016%, Si: 0.016%, Alt: 0.028%, Ca: 0.0013%, calculate the calcium recovery rate: the weight of the molten steel is 90t, the calcium content of each meter of calcium wire is 60g, the purity of the calcium wire is 98%, and the recovery rate of the calcium wire is 12.28%.

[0036] Comparative Example 2 To smelt MR T2.5 steel, after the molten steel enters the station, the electrode is inserted into the ladle and the electricity is turned on to heat it up. During the heating process, slag-making materials, lime, aluminum chips, etc. are added to adjust the slag. After the heating is completed, the temperature of the molten steel is 1630℃, and the refined slag is observed to be white.

[0037] Sampling was taken to test the chemical composition of the molten steel, showing C: 0.045%, Mn: 0.25%, S: 0.010%, P: 0.015%, Si: 0.015%, and Alt: 0.030%.

[0038] The ladle has double-hole bottom blowing. The flow rate of bottom blowing argon is reduced from 500L / min to 200L / min. The wire feeding position is on the extension line of the line connecting the center of the two bottom blowing holes and the center of the bottom circle of the ladle. The amount of calcium wire added is 200m; after the wire feeding is completed, the wire feeding device is removed.

[0039] After blowing argon for 8 minutes, samples were taken to test the composition of the molten steel. C: 0.045%, Mn: 0.25%, S: 0.006%, P: 0.016%, Si: 0.016%, Alt: 0.028%, Ca: 0.0018%, Calculate the calcium recovery rate: the weight of molten steel is 90t, the calcium content of each meter of calcium wire is 60g, the purity of calcium wire is 98%, and the recovery rate of calcium wire is 17.01%.

[0040] It can be seen from the above comparative examples that the calcium wire yield rate using the method of the present invention is more than 10% higher than that not using the method of the present invention.

Claims

1. A device for improving the yield of calcium treatment in ladle refining, characterized in that: It comprises a wire feeding machine, a traveling vehicle (1), a lifting part, a limiting part, a rotating part and a wire control part; the wire feeding machine and the traveling vehicle (1) are both arranged on the ground; the lifting part is arranged on the traveling vehicle (1); the limiting part and the rotating part are both arranged on the lifting part; and the wire control part is arranged on the rotating part.

2. The device for improving the calcium treatment yield of ladle refining according to claim 1, characterized in that: The lifting part comprises a vertical plate (2), a hoist (3), a first slide plate (4) and a lifting horizontal plate (5); the vertical plate (2) is arranged on the side wall of the traveling vehicle (1); a support plate is arranged at the top of the vertical plate (2), and the hoist (3) is arranged on the support plate; a slide rail is arranged on the side wall of the vertical plate (2) along the vertical direction, and the first slide plate (4) is slidably arranged on the slide rail; the lifting horizontal plate (5) is arranged on the first slide plate (4); the end of the pull rope of the hoist (3) is connected to the lifting horizontal plate (5); a scale is arranged on the side wall of the vertical plate (2) along the vertical direction, and a pointing plate is arranged on the side wall of the lifting horizontal plate (5), and the pointing plate corresponds to the scale position on the side wall of the vertical plate (2).

3. The device for improving the calcium treatment yield of ladle refining according to claim 2, characterized in that: The rotating part comprises a limit ring (6), a disc (7), a first motor (8) and a driving gear; the limit ring (6) is arranged on the lifting horizontal plate (5); the upper end surface of the limit ring (6) is provided with a circle of limit grooves, the bottom end surface of the disc (7) is provided with a circle of limit strips, and the limit strips at the bottom end of the disc (7) are slidably arranged in the limit grooves of the limit ring (6); the first motor (8) is arranged at the edge of the upper end surface of the limit ring (6) through a bracket, and the end of its output shaft is provided with a driving gear; a circle of teeth is provided on the circumferential side wall of the disc (7), and the teeth of the driving gear are meshed and transmission-connected with the teeth on the side wall of the disc (7).

4. The device for improving the calcium treatment yield of ladle refining according to claim 3 is characterized in that: The limiting part comprises a horizontal guide rod (9), a sliding rod, a U-shaped plate (10), a rotating plate (11) and a limiting mechanism; the horizontal guide rod (9) is arranged on the lifting horizontal plate (5) through a bracket, and a guide hole is arranged at the end of the horizontal guide rod (9); the sliding rod is inserted into the guide hole at the end of the horizontal guide rod (9); the U-shaped plate (10) is arranged at the end of the sliding rod; the center of the rotating plate (11) is axially connected to the inner wall of the U-shaped plate (10) through a rotating shaft, and the axis of the rotating shaft is a vertical direction line; the number of the limiting mechanisms is two, and both are arranged on the rotating plate (11).

5. The device for improving the calcium treatment yield of ladle refining according to claim 4, characterized in that: The limiting mechanism comprises a slider (12), a vertical round rod (13), a lower long rod (14) and an upper long rod (15); a sliding groove is provided on the end surface of the rotary plate (11) away from the sliding rod, and the slider (12) is slidably arranged in the sliding groove of the rotary plate (11); the vertical round rod (13) is arranged on the top surface of the slider (12); the ends of the lower long rod (14) and the upper long rod (15) are both provided with insertion holes, and the insertion holes at the ends of the lower long rod (14) and the upper long plate are both penetrated by the vertical round rod (13).

6. The device for improving the calcium treatment yield of ladle refining according to claim 5, characterized in that: The wire control part comprises a transverse movement mechanism and a wire release mechanism; the transverse movement mechanism is arranged on a disc (7), and the wire release mechanism is arranged on the transverse movement mechanism.

7. The device for improving the calcium treatment yield of ladle refining according to claim 6, characterized in that: The transverse movement mechanism comprises a second motor (16), a lead screw, a lead screw nut (17) and a second slide plate (18); the upper end surface of the disk (7) is provided with a strip hole along the diameter direction, and the length of the strip hole is equal to the radius of the disk (7); the second motor (16) and the support plate are both arranged on the upper end surface of the disk (7), and are respectively located at two ends of the strip hole; one end of the lead screw is connected to the output shaft of the second motor (16), and the other end of the lead screw is axially connected to the support plate; the lead screw nut (17) is arranged on the lead screw; the second slide plate (18) is slidably arranged in the strip hole of the disk (7), and the lead screw nut (17) is connected to the second slide plate (18).

8. The device for improving the calcium treatment yield of ladle refining according to claim 7, characterized in that: The wire-releasing mechanism comprises a curved tube (19), a vertical hollow tube (20) and a high-temperature resistant tube (21); a vertical hole is provided on the second slide plate (18), and the vertical hollow tube (20) is provided in the vertical hole; the high-temperature resistant tube (21) is provided at the bottom end of the vertical hollow tube (20), and the bottom end hole of the vertical hollow tube is connected to the top end hole of the high-temperature resistant tube (21); a joint is provided at the top end of the side wall of the high-temperature resistant tube (21), and the joint is connected to the inner cavity of the high-temperature resistant tube (21); a circle of sliding grooves is provided at the top end of the inner wall of the vertical hollow tube (20), and a circle of sliding strips is provided at the end of the outer wall of the curved tube (19), and the sliding strips on the outer wall of the curved tube (19) are slidably provided in the sliding grooves at the top end of the inner wall of the vertical hollow tube (20).

9. The device for improving the calcium treatment yield of ladle refining according to claim 8, characterized in that: The calcium wire passes through the wire feeding machine, the bending pipe (19), the vertical hollow pipe (20) and the high temperature resistant pipe (21) in sequence and then enters the molten steel in the ladle.

10. A method for improving the calcium treatment yield of ladle refining according to any one of claims 1 to 9, characterized in that: The steps include: Step 1: Adjust the slag of the ladle. According to the condition of the slag, add aluminum powder, lime, refined slag, etc. to adjust the slag. The Alt content of the molten steel before feeding the calcium line is required to be controlled at 0.020%-0.040%, the S content is ≤0.012%, and the temperature T is controlled at 1620-1630℃; Take a sample after the slag is adjusted, and then take a sample again after an interval of 3 minutes. The oxidizability of the molten steel is determined by analyzing the full composition of the steel. The specific determination is: ΔAlt=Alt1-Alt2≤0.002%, ΔSi=Si2-Si1≥0.005%; In the formula, ∆Alt and ∆Si are the differences between the components analyzed in two samplings; Alt1 and Si1 are the composition values ​​of the first sampling analysis; Alt2 and Si2 are the component values ​​of the second sampling analysis; When it is determined that the requirements are met, it can be determined that the molten steel is in a weakly oxidizing or reducing state, and the calcium wire can be added; Step 2: Push the travel vehicle (1) to move in front of the ladle, and adjust the position of the travel vehicle (1) so that the axis of the disc (7) coincides with the center axis of the ladle; if the ladle has a single argon blowing hole at the bottom, and control a limit mechanism to move, drive a slider (12) to move to the position just above the bottom argon blowing hole, and then swing the lower long rod (14) and the upper long rod (15), the two long rods are respectively in different directions and are fifteen degrees apart from the connecting line of the slider (12) and the center point of the disc (7); the area between the upper long rod (15) and the lower long plate is a fan-shaped area, and the subsequent position of the wire-releasing mechanism needs to be adjusted to the fan-shaped area between the upper long rod (15) and the lower long plate; If there are two argon blowing holes at the bottom of the ladle, the two sliders (12) are controlled to move respectively to the top of the two argon blowing holes at the bottom, and then the upper long rod (15) on one slider (12) is controlled to move, and the lower long rod (14) on the other slider (12) is controlled to move, and the two moving long rods are made to pass through the axis of the disk (7). At this time, the fan-shaped area of ​​the angle between the lower long rod (14) and the upper long rod (15) is the position range of the subsequent wire release mechanism; Step 3: adjusting the position of the wire-releasing mechanism so that it falls into the designated sector-shaped area; the first motor (8) is driven to rotate the disc (7), and the second motor (16) is driven to slide the second slide plate (18), and the two cooperate to adjust the position of the direction mechanism so that the wire-releasing mechanism falls into the designated sector-shaped area, and then fine-tuning the position of the wire-releasing mechanism so that the minimum distance between the high-temperature resistant tube (21) and the inner wall of the ladle is within the range of 0.3 to 0.5 times the inner diameter of the ladle; Step 4: Control the hoist (3) to move, drive the lifting horizontal plate (5) downward, and drive the remaining parts arranged on the lifting horizontal plate (5) to move downward synchronously; until the bottom end of the high-temperature resistant tube (21) contacts the steel slag, and then according to the coordination of the hoist (3) and the scales on the side wall of the vertical plate (2), the bottom end of the high-temperature resistant tube (21) is moved into the molten steel, and it is ensured that the insertion depth of the bottom end of the high-temperature resistant tube (21) is greater than 300 mm, and the distance between the bottom end and the bottom end of the ladle is greater than 1000 mm; Step 5: before wire feeding, the argon flow rate of the ladle bottom blowing is 300L / min-500L / min; during wire feeding, the argon flow rate of the ladle bottom blowing is 100L / min-200L / min; during wire feeding, the joint at the top of the high temperature resistant tube (21) is connected to the argon source, and the argon flow rate in the high temperature resistant tube (21) is 100L / min-200L / min; when wire feeding starts, the calcium wire passes through the wire feeding machine, the curved tube (19), the vertical hollow tube (20) and the high temperature resistant tube (21) in sequence and then enters the molten steel in the ladle; after wire feeding is completed, the device is removed and the ladle returns to the normal argon blowing state.

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