JPH0892626A - Steelmaking equipment for refining equipment - Google Patents

Abstract

PURPOSE: To prevent the intrusion of slag into molten steel at the time of tapping from a converter. CONSTITUTION: A linear motor 3 is installed between a tap hole 1a and a furnace bottom 1c along the peripheral wall of a furnace body 1 to generate moving magnetic fields in the direction toward the tap hole 1a from the furnace bottom 1c at the time of tapping. Flow is generated in the molten steel 9 and the flow is not generated in the slag 8. Since a build-up is generated in the molten steel 9 and, therefore, the outflow of only the molten steel 9 out of the tap hole 1a is possible at the time of starting the tapping or ending the tapping.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel output device for refining equipment such as blast furnace equipment, converter equipment, pretreatment equipment and secondary refining equipment.

[0002]

2. Description of the Related Art In a refining facility such as a converter, for example, when refining is completed, the furnace is tilted to transfer the molten steel in the furnace to a molten steel ladle, and the molten steel ladle is sent to the next step by a steel carrier.
The following conventional techniques are known for this type of tapping.

An electromagnetic stirrer is installed around the tapping mouth of the converter to stir the tapped steel stream.

A linear coil is installed around the tapping port of the converter to brake the tapping flow.

[0005]

By the way, the slag and the molten steel are present in a state where they are vertically separated from each other inside the converter after the refining is completed. Moreover, only the molten steel needs to be transferred from the converter to the molten steel ladle at the time of tapping, and the molten steel and the slag must be separated. However, when the converter is tilted to start tapping, not only molten steel but slag temporarily flows out to the tapping port. Further, when the completion time of tapping approaches, the amount of molten steel in the converter decreases, so that the slag again flows out to the tapping port. Therefore, it is difficult to output only molten steel to the molten steel ladle. Further, when the stirring is performed in the vicinity of the tap hole, the molten steel and the slag are mixed, and thus it is difficult to separate them again.

An object of the present invention is to reduce the amount of impurities such as slag mixed in molten steel during tapping.

[0007]

In order to solve the above-mentioned problems, a steel output device for refining equipment of the present invention is a furnace (1) in which molten steel and slag are held, and an attitude adjustment for adjusting the inclination of the furnace. Refining equipment including mechanism (2); tapping port (1a) of the furnace
Exciting means (3) including a plurality of electric coils arranged in the height direction of the furnace along the outer peripheral wall of the furnace belly side of the bottom of the furnace; steel is tapped from the bottom of the furnace by controlling the exciting means. Excitation control means (5) for generating a moving magnetic field in the direction toward the mouth and forming a rise (4a) of molten steel in the vicinity of the tapping mouth; and adjusting the inclination (θ) of the furnace and tapping A tapping control means (6) for controlling the outflow of molten steel from the mouth is provided.

Further, according to a second aspect of the present invention, the tapping control means adjusts the inclination of the furnace until the position of the upper surface of the slag in the furnace approaches the tapping port in response to the tapping start instruction, and then the excitation control is performed. It includes means (S22 to S26) for instructing the means to generate the moving magnetic field, detecting the outflow of the molten steel from the tapping mouth, and then adjusting the inclination of the furnace according to the detected tapping flow rate.

Further, according to a third aspect of the present invention, in response to the tapping start instruction, the tapping control means adjusts the inclination of the furnace until the position of the upper surface of the slag in the furnace approaches the tapping port, and then the excitation control is performed. Means for instructing the means to generate the moving magnetic field, detecting the outflow of molten steel from the tapping mouth, and then adjusting the strength of the moving magnetic field according to the detected tapping flow rate (S82 to S86).
including.

According to the present invention, a plate-like member (7) made of a magnetic material is installed along the outer peripheral wall of the furnace abdomen between the furnace and the exciting means.

The symbols shown in the above parentheses are the reference numerals of the corresponding elements in the embodiments described later, but each component of the present invention is a specific element in the embodiments. It is not limited to only.

[0012]

In the present invention, the exciting means (3) installed in the furnace (1) is arranged along the outer peripheral wall of the furnace abdomen on the furnace bottom side with respect to the steel tapping port (1a) of the furnace. It includes a plurality of electric coils arranged toward each other. Further, the excitation control means (5) controls the excitation means to generate a moving magnetic field in the direction from the furnace bottom side to the tap hole, and forms a rise (4a) of molten steel in the vicinity of the tap port. Further, the tapping control means (6) is
The outflow of molten steel from the tap hole is controlled by adjusting the inclination (θ) of the furnace.

Molten steel and slag are present in a vertically separated state inside the furnace where the refining is completed. That is, Si, Mn,
Since the specific gravity of slag made of a compound such as P is about 1 to 2, and the specific gravity of molten steel is about 7, as shown in FIG.
Molten steel sinks below and slag floats on it. When the exciting means is energized, a moving magnetic field in the direction from the furnace bottom side to the tap hole is generated near the furnace abdominal outer peripheral wall of the furnace by the plurality of electric coils. By the way, since molten steel is a conductor, when the moving magnetic field is generated, an eddy current flows in the molten steel in the vicinity thereof. Then, the interaction between the eddy current and the moving magnetic field causes a flow in the molten steel. On the other hand, since the slag is an insulator, no flow occurs in the slag. Also,
The flow generated in the molten steel flows in the direction from the furnace bottom side to the tap hole. Therefore, due to the flow in the molten steel, a rise (4a) of the molten steel is formed in the vicinity of the tap hole of the furnace as shown in FIG. When the moving magnetic field is sufficiently strong, the position of the rising portion of the molten steel is higher than the upper surface of the slag.
If the inclination of the furnace is increased or the strength of the moving magnetic field is increased in that state, the position of the top of the molten steel becomes higher than the tap hole, so that the molten steel flows out from the tap port. Moreover, since the upper surface position of the slag at this time can be maintained lower than the tap hole, only the molten steel can be made to flow out from the tap port. Therefore, the amount of impurities such as slag mixed in the molten steel at the time of tapping can be reduced.

In the present invention, when the tapping start instruction is issued, the inclination of the furnace is adjusted until the slag upper surface position in the furnace approaches the tapping port, and then the excitation control means is instructed to generate the moving magnetic field. Then, after detecting the outflow of molten steel from the tapping port, the inclination of the furnace is adjusted according to the detected tapping flow rate. That is,
After tapping is started, the tapping flow rate is maintained at its target value by adjusting the inclination of the furnace.

According to the third aspect of the present invention, when the tapping start instruction is issued, the inclination of the furnace is adjusted until the slag upper surface position in the furnace approaches the tapping port, and then the moving magnetic field is generated by the excitation control means. After instructing and detecting the outflow of molten steel from the tapping port, the strength of the moving magnetic field is adjusted according to the detected tapping flow rate. That is, after the tapping is started, the magnitude of the flow in the molten steel is adjusted by adjusting the strength of the moving magnetic field, and the tapping flow rate is maintained at the target value. If all the molten steel cannot be tapped by adjusting only the strength of the moving magnetic field, adjustment of the inclination of the furnace may be used together.

According to the present invention, since the plate member (7) made of a magnetic material is installed along the outer peripheral wall of the furnace between the furnace and the exciting means, the outer peripheral wall of the furnace. A magnetic path can be formed along with to form a stable flow in the molten steel.

[0017]

EXAMPLES An example of the structure of a converter for carrying out the present invention is shown in FIG. This will be described with reference to FIG. The furnace body 1 is formed in a pot shape having a circular cross section, and most of the peripheral wall and the like are made of refractory material. The inside of the furnace body 1 is hollow,
An opening 1b is formed at the top, and a tap hole 1a, which is a relatively small opening, is formed at the furnace abdomen. 1c is the bottom of the furnace. The furnace body 1 includes a trunnion ring 1 that surrounds the central portion of the furnace body 1.
It is configured integrally with 1. The shaft 12 of the trunnion ring 11 is rotatably supported by the bearing of the tilting device 2. Further, the gear 13 fitted to the shaft 12 is connected to the drive shaft of the electric motor 15 via the speed reducer 14. Therefore, by driving the electric motor 15, the trunnion ring 11 can be rotated about the shaft 12 and the furnace body 1 can be tilted.

The molten steel before the refining treatment is poured into the furnace body 1 through an opening 1b at the top by an unillustrated equipment installed above, in a state where the furnace body 1 is not tilted as shown in FIG. Be refined. Impurities contained in the molten steel before treatment, that is, C, Si, Mn, P, S, etc. are separated by refining. A part of the separated impurities is released to the outside of the furnace body 1 as a gas, and the remaining impurities (compounds such as Si, Mn, P) remain in the furnace body 1 as slag 8. The slag 8 has a specific gravity of about 1 to 2, and the molten steel 9 separated from the impurities has a specific gravity of about 7. Therefore, as shown in FIG.
The slag 8 floats above the bottom of the slag.

When the refining is completed and the steelmaking operation is started, a molten steel ladle 16 is arranged below the furnace body 1 as shown in FIG. When the furnace body 1 is tilted, the position of the tapped steel port 1a is lowered, so that the molten steel 9 flows out from the tapped steel port 1a and moves to the molten steel ladle 16. Since the molten steel ladle 16 is supported on the steel receiving cart 17, it can be moved along the rail 18. A load cell 19 for detecting the weight of tapped steel is installed between the steel receiving cart 17 and the molten steel ladle 16.

By the way, since the slag 8 is located above the molten steel 9, when the inclination of the furnace body 1 is gradually increased from the state shown in FIG. 3, first, a part of the upper slag 8 is tapped. When flowing out from the opening 1a and further increasing the inclination, the molten steel 9 on the lower side flows out from the tapping opening 1a. Therefore, the slag 8 mixes with the molten steel 9 in the molten steel ladle 16. In order to avoid such a problem, as shown in FIG. 3, a linear motor 3 is installed along the outer peripheral surface of the furnace abdomen of the furnace body 1 between the tap hole 1a and the furnace bottom 1c. is there.

An enlarged view of the portion of the linear motor 3 shown in FIG. 3 is shown in FIG. This will be described with reference to FIG. The cores (iron cores) 31 of the linear motor 3 are arranged along the furnace wall of the furnace body 1 and are formed at equal intervals in the vertical direction (direction from the furnace bottom to the furnace top of the furnace body). Has slots. An electric coil 32 is installed in each slot. The 24 electric coils 32 are connected to each other in series, four adjacent to each other, forming six groups. These electric coils 32 have three-phase AC power U,
V and W are supplied. The phases of the power supplied to the six groups are + U, -V, + W, -U, + V, in order from the bottom.
-W, and have a phase difference of 60 degrees from each other. Therefore, when electric power is supplied to the electric coil of the linear motor 3, as shown in FIG. 7, a moving magnetic field is formed along the furnace wall of the furnace body 1 in the direction from the furnace bottom side to the tap hole 1a.

A cross section of the furnace body 1 is shown in FIG. Referring to FIG. 6, the core 31 is formed in an arc shape along the peripheral wall of the furnace body. A thin plate 7 made of stainless steel is mounted on the outer peripheral surface of the furnace body 1 facing the linear motor 3. Since the thin plate 7 is a ferromagnetic material, the magnetic path of the linear motor 3 is formed thereby. That is, the magnetic path of the linear motor 3 is formed along the peripheral wall of the furnace body.

When electric power is supplied to the electric coil of the linear motor 3, a moving magnetic field as shown in FIG. 7 is generated. Therefore, as shown in FIG. Flow A1 in the direction from the side toward the tap hole 1a, and in a portion of the molten steel 9 away from the linear motor 3, a flow A2 in the direction from the tap port 1a to the furnace bottom side occurs. However, no flow occurs in the slag 8. Such a flow A
Due to 1, A2, a rise 4a is generated in the molten steel 9 in the vicinity of the tap hole 1a. When the driving force of the linear motor 3 is sufficiently large, the height of the raised portion 4a becomes higher than the upper surface of the slug 8. Therefore, since the slag 8 is shielded from the steel tap 1a by the rise 4a in the molten steel 9, the slag 8 may flow out from the tap 1a even if the inclination of the furnace body 1 is increased. Instead, it becomes possible to tap only the molten steel 9.

FIG. 9 shows the configuration of an electric circuit for controlling tapping of the converter equipment shown in FIG. This will be described with reference to FIG. The control unit 6 is composed of a microcomputer or the like, and controls the electric motor 15 and the linear motor 3 when tapping the steel from the converter. The control unit 6 includes
From the process computer PC, a tapping instruction and information on the total weight of molten steel in the furnace body 1 are input. The table TBL holds the values of various parameters used by the control unit 6. For example, since the conditions such as the inclination of the furnace body 1 when tapping is started change according to the total weight of molten steel in the furnace body 1,
The table TBL holds all such parameter values for each total weight of molten steel.

The potentiometer PM is connected to the shaft 12 that supports the furnace body 1, and detects the inclination θ of the furnace body 1. In this example, as shown in FIGS. 1 and 3, the inclination θ in the state where the furnace top opening 1b faces upward is set to 0 degree. The signal output from the potentiometer PM is input to the control unit 6 via the A / D converter AD1. Low
The doscel 19 is arranged below the molten steel ladle 16 as shown in FIG. 3, and detects its weight. Load cell 19
By subtracting the own weight of the molten steel ladle 16 from the weight detected by, the weight of molten steel in the molten steel ladle 16, that is, the weight of tapped steel up to that point can be obtained. Further, the tapped steel flow rate is obtained as a change in the tapped steel weight per unit time. The signal output from the load cell 19 is input to the control unit 6 via the A / D converter AD2.

The electric motor 15 for rotating the shaft 12 is
It is connected to the control unit 6 via the motor driver DRV. A control unit 6 is connected to a three-phase AC power supply 5 that supplies electric power to the linear motor 3. The control unit 6 outputs to the motor driver DRV a signal indicating ON / OFF of driving and a signal indicating the rotation direction of the motor. Further, to the three-phase AC power supply 5, a signal indicating ON / OFF of power supply and a signal for determining the value of current flowing through the linear motor 3 are output.

The structure of the three-phase AC power supply 5 of FIG. 9 is shown in FIG. This will be described with reference to FIG. The AC power supplied from the three-phase power supply 21 is rectified by the thyristor bridge 22 and smoothed by the inductor 25 and the capacitor 26. Therefore, a DC voltage appears between the terminals of the capacitor 26. The voltage appearing across the terminals of capacitor 26 varies depending on the phase at which thyristor bridge 22 is triggered. The voltage command value Vdc applied to the phase angle calculator 24 is a signal from the control unit 6 and adjusts the DC voltage appearing between the terminals of the capacitor 26 to obtain a linear mode.
It is used to adjust the current flowing through the electric coil of the controller 3. The phase angle calculator 24 calculates the trigger phase angle α corresponding to the voltage command value Vdc. The gate driver 23 generates a trigger signal applied to each gate terminal so as to trigger each thyristor of the thyristor bridge 22 with the trigger phase angle α output by the phase angle calculator 24.
That is, a zero-cross point of an AC waveform that each thyristor switches is detected, and a trigger signal is generated when a time corresponding to the phase angle α has elapsed after the zero-cross point was detected.

The transistor bridge 27 switches the DC voltage appearing between the terminals of the capacitor 26 to generate three-phase AC voltages U, V, W. A signal for controlling the switching of the transistor bridge 27 is generated by the comparator 29 and applied to the base terminal of each transistor via the gate driver 28. The output of the signal generator SG and the output of the triangular wave generator 30 are connected to the input terminal of the comparator 29. The signal generator SG has a frequency of 2H.
Three-phase AC voltages U1, V1, W1 of z sine wave are output. U1 and V1 and V1 and W1 each have a phase difference of 120 degrees. Further, the triangular wave generator 30 outputs a triangular wave signal having a repetition frequency of 3 KHz. The comparator 29 has six analog comparators built-in, and the positive half-wave voltage and the negative half-wave voltage of the three-phase AC voltages U1, V1, and W1 are triangular wave generators which are independent analog comparators. Three
0 is compared with the triangular wave voltage output, and the comparison results are output as six binary signals. These binary signals are applied to the transistor bridge 27 via the gate driver 28, and three-phase AC voltages U, V, W appear at the output of the transistor bridge 27.

Although not shown, a relay is inserted between the three-phase AC power supply 21 and the thyristor bridge 22, and the relay is switched by the ON / OFF signal output from the control unit 6, and the linear motor is operated. The power supply to the controller 3 can be turned on / off.

FIG. 2 shows an outline of the operation of the control unit 6 relating to tapping, and FIG. 10 shows changes in the state of the apparatus of the embodiment during tapping. The operation of the control unit 6 will be described with reference to FIG. In the first step S21, each part is initialized. For example, the driving of the electric motor 15 is stopped, and the power supply to the linear motor 3 is also stopped. Information on the total weight of molten steel is input from the process computer PC, and the values of various parameters corresponding to the information are input from the table TBL.

In step S22, the process waits until refining in the converter is completed and a steel output start instruction is input from the process computer PC. When the tapping start instruction is input, the process proceeds to the next step S23.

In step S23, the electric motor 15 is driven so as to rotate the furnace body 1 in the direction in which the position of the tap hole 1a is lowered (counterclockwise in FIGS. 3 and 4). And
The inclination θ of the furnace body is detected by the potentiometer PM.
The detected inclination .theta. Is compared with a constant .theta.1 (a parameter previously input from TBL and determined), and if they do not match, the drive of the electric motor 15 is continued. That is, the furnace body 1 is tilted from the state where the tilt θ is 0 degree until the tilt θ becomes θ1.

When θ = θ1 in step S23, the process proceeds to step S24, and the driving of the electric motor 15 is stopped. In this state, as shown in FIG. 4, both the positions of the upper surface of the molten steel 9 and the upper surface of the slag 8 are located below the lower end of the tap hole 1a, so that both the molten steel 9 and the slag 8 are tapped. Does not flow out of the mouth 1a.

In the following step S25, the linear motor 3 is
Apply a specified current to the electric coil. As a result, due to the moving magnetic field generated by the linear motor 3, flows A1 and A2 are generated in the molten steel 9, and a protuberance 4a is formed on the upper surface of the molten steel 9 in a portion near the linear motor 3. In step S25, the current value of the linear motor 3 is set so that the position of the top of the ridge 4a is higher than the upper surface of the slug 8. Therefore, the space between the slag 8 and the tap hole 1a is shielded by the rising 4a of the molten steel 9, so that the slag 8 is prevented from flowing out from the tap port 1a. Further, the current value of the linear motor 3 is set so that the position of the top of the rising 4a is higher than the lower end of the tap hole 1a. Therefore, the molten steel 9 flows out from the rising portion 4a toward the tapping opening 1a. That is, tapping is started.

In the next step S26, the tapped steel flow rate Q is first obtained from the change in the tapped steel weight detected by the load cell 19 per unit time. Further, the inclination θ of the furnace body is detected by the potentiometer PM. Then, the furnace inclination θx required to bring the tapping flow rate Q to the target value Qx is obtained, and the electric motor 15 is driven so that the furnace inclination becomes θx. That is, the inclination of the furnace is automatically adjusted so that the tapping flow rate Q is maintained at the target value Qx. For example, when the amount of molten steel in the furnace body 1 decreases as the tapping progresses, the liquid level of the molten steel 9 decreases and the flow rate decreases. Therefore, in order to raise the liquid level of the molten steel 9, the furnace inclination θ To maintain the flow rate Q constant.

When the remaining amount of the molten steel 9 in the furnace body 1 is reduced to a certain extent, the flow rate Q is remarkably reduced, and it becomes impossible to maintain Q constant even if the inclination θ of the furnace is adjusted. Therefore, in step S26, the inclination θ is compared with a constant θ2 (parameter previously input from TBL and determined), and when θ = θ2, the process proceeds to the next step S27.

In step S27, the electric motor 15 is driven at a constant speed in the direction in which the inclination θ of the furnace body 1 increases. Further, the tapped steel weight W detected by the load cell 19 is input, and W is compared with a constant WT (parameter previously input from TBL and determined). When the remaining amount of the molten steel 9 in the furnace body 1 becomes extremely small, W = WT, and steps S27 to S
Proceed to 28. The constant WT is a value slightly smaller than the weight of the molten steel 9 in the furnace body 1 before the start of tapping.

In step S28, the electric motor 15 is reversely driven so as to rotate the furnace body 1 in the direction in which the inclination θ becomes smaller (clockwise direction in FIG. 3). In addition, the inclination θ of the furnace body is detected by the potentiometer PM, and θ is a constant θ.
3 (parameter previously input from TBL and determined). Then, when θ = θ3, the process proceeds to the next step S29, and the energization of the linear motor 3 is stopped. In this example,
The inclination of the furnace body 1 when the upper surface position of the slag 8 remaining in the furnace body 1 is lower than the lower end of the tap hole 1a is defined as θ3. Therefore, when the energization of the linear motor 3 is stopped in step S29, the rising 4a in the molten steel disappears and the outflow of the molten steel 9 from the tap hole 1a is stopped, but at that time, the slag 8 is discharged from the tap hole 1a. It will not be leaked. That is, it is possible to prevent the slag 8 from mixing with the molten steel in the molten steel ladle 16 even when the tapping is finished.

In the next step S2A, the electric motor 15 is reversely driven so that the furnace body 1 is further rotated in the direction in which the inclination θ becomes smaller. Further, the inclination θ of the furnace body is detected by the potentiometer PM, and the inclination is adjusted until θ becomes zero. When the inclination θ becomes 0, the driving of the electric motor 15 is stopped in step S2B.

FIG. 8 shows the operation of the control unit 6 in the modified embodiment, and FIG. 11 shows the state change of this apparatus during tapping. The operation of the control unit 6 will be described with reference to FIG. Steps S81 to S85 are the same as steps S21 to S25 of the above embodiment. That is, the first step S
In 81, each part is initialized, and the next step S82.
Then, the process waits until a tapping start instruction is input from the process computer PC, and in the next step S83, the furnace body 1
Is inclined from the state where the inclination θ is 0 degree until the inclination θ becomes θ1. Further, in step S84, driving of the electric motor 15 is stopped, and in a succeeding step S85, a predetermined current is supplied to the electric coil of the linear motor 3.

When step S85 is executed, the linear mode
The moving magnetic field generated by the rotor 3 causes a flow A in the molten steel 9.
1 and A2 are generated, and molten steel 9 is present in the portion close to the linear motor 3.
4a is formed on the upper surface of the. In step S85, the current value of the linear motor 3 is set so that the position of the top of the rising 4a is higher than the upper surface of the slug 8. Therefore, the space between the slag 8 and the tap hole 1a is shielded by the rising 4a of the molten steel 9, so that the slag 8 is prevented from flowing out from the tap port 1a. Further, the current value of the linear motor 3 is set so that the position of the top of the rising 4a is higher than the lower end of the tap hole 1a. Therefore, the molten steel 9 flows out from the rising portion 4a toward the tapping opening 1a. That is, tapping is started.

In the next step S86, the tapped steel flow rate Q is first obtained from the change in the tapped steel weight detected by the load cell 19 per unit time. Then, the current value of the linear motor 3 required to set the tapping flow rate Q to the target value Qx is obtained, and the information corresponding to the current value is output to the three-phase AC power supply 5. That is, the current value of the linear motor 3 is automatically adjusted so that the tapping flow rate Q is maintained at the target value Qx. For example, with the outflow of the molten steel 9 from the tap hole 1a, the amount of molten steel in the furnace body 1 decreases and the liquid level decreases, so the height of the rising portion 4a relative to the tap hole 1a also decreases,
If the current value of the linear motor 3 is increased, the rise 4a is increased, so that it is possible to compensate so that the tapped steel flow rate Q does not decrease.

However, since it is difficult to produce all the molten steel in the furnace body 1 only by controlling the current value of the linear motor 3,
In this embodiment, the tapping flow rate is controlled by adjusting the inclination θ of the furnace body 1 together. That is, in step S86, the weight W of tapping steel is detected by the load cell 19, this weight W is compared with a constant Wn (Wn = W1, W2, W3, W4), and when W matches any of Wn, To step S87.

In step S87, the target value θx of the inclination of the furnace body is corrected until the inclination θ of the furnace body matches θx.
The electric motor 15 is driven in the direction in which the inclination increases.
That is, the inclination of the furnace body is increased. Then, the inclination θ of the furnace body is detected by the potentiometer PM, and the inclination θ is a constant θ.
Compare with 2. If θ <θ2, step S86 again
Then, the flow rate of tapping steel Q is controlled to be constant. θ =
When θ2 is reached, the process proceeds to step S88.

In steps S86 and S87, the inclination θ is adjusted so that the position of the upper surface of the slag 8 is maintained lower than the lower end of the tap hole 1a. Therefore, the slag 8 is prevented from flowing out of the tap hole 1a.

Steps S88 to S8C are steps S of the above embodiment.
This is similar to the processing of 27 to S2B. That is, step S8
In No. 8, when the inclination θ of the furnace body 1 is increased, the electric motor 15 is driven at a constant speed, and when the remaining amount of the molten steel 9 in the furnace body 1 becomes extremely small, the process proceeds to S89. In step S89, the electric motor 15 is reversely driven so as to rotate the furnace body 1 in the direction in which the inclination θ becomes smaller (clockwise direction in FIG. 3), and when θ = θ3, the process proceeds to the next step S8A, The energization of the linear motor 3 is stopped. In the next step S8B, the electric motor 15 is reversely driven so that the furnace body 1 is rotated in the direction in which the inclination θ becomes smaller, and the inclination is adjusted until θ becomes zero. When the inclination θ becomes 0, step S8
At C, the driving of the electric motor 15 is stopped.

In the above embodiment, step S2
The current of the linear motor is rapidly raised in S5 and S85, but the control may be changed so that the current value of the linear motor is gradually increased until tapping is started. Further, in the embodiment, the current value of the linear motor is set to 0 when the inclination θ of the furnace body is between 0 and θ1, but the current may be supplied to the linear motor even when the inclination θ is between 0 and θ1. Further, in the embodiment, the current value of the linear motor is rapidly cut off when the tapping is finished, but the current value may be controlled to be gradually decreased.

[0048]

As described above, according to the present invention, the moving magnetic field formed by the exciting means forms the bulge 4a in the molten steel 9 in the vicinity of the tapping hole, so that the tapping is started or tapped. Even at the end, only the molten steel 9 can be made to flow out from the tapping port 1a. Therefore, the amount of impurities such as slag mixed in the molten steel at the time of tapping can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a converter equipment of an embodiment as seen from the front.

FIG. 2 is a flowchart showing the operation of the control unit 6.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a cross-sectional view showing various states of the furnace body 1 having different inclinations θ.

5 is a vertical cross-sectional view showing an enlarged portion of the linear motor 3 in FIG.

FIG. 6 is a transverse cross-sectional view showing the furnace body 1 and the linear motor 3.

FIG. 7 is a vertical sectional view showing a moving magnetic field generated by the linear motor 3.

FIG. 8 is a flowchart showing the operation of the control unit 6 of a modified example.
It is a chart.

FIG. 9 is a block diagram showing an electric circuit of the apparatus of the embodiment.

FIG. 10 is a time chart showing a state change of each part of the apparatus of the embodiment.

FIG. 11 is a time chart showing a state change of each part of the modified device.

12 is a block diagram showing a configuration of the three-phase AC power supply of FIG.

[Explanation of symbols]

1: Furnace body 1a: Steel tap 1b: Opening 1c: Furnace bottom 2: Tilt device 3: Linear motor 4a: Rise 5: Three-phase AC power supply 6: Control unit 7: Thin plate 8: Slag 9: Molten steel 11: Trunnion ring 12: Shaft 13: Gear 14: Reducer 15: Electric motor 16: Ladle ladle 17: Steel trolley 18: Rail 19: Load cell 31: Core 32: Electric coil PC: Process computer PM: Potentiometer

Claims (4)

[Claims] 1. A refining facility including a furnace in which molten steel and slag are held, and a posture adjusting mechanism for adjusting the inclination of the furnace; along a furnace belly outer peripheral wall on the furnace bottom side with respect to the tap hole of the furnace. An exciting means including a plurality of electric coils arranged in the height direction of the furnace; controlling the exciting means to generate a moving magnetic field in a direction from the furnace bottom side to the tap hole, and near the tap hole A steel output device for refining equipment, which comprises: an excitation control means for forming a rise of molten steel; and a steel output control means for controlling the outflow of the molten steel from the steel output port by adjusting the inclination of the furnace. 2. The tapping control means, in response to a tapping start instruction, adjusts the inclination of the furnace until the position of the upper surface of the slag in the furnace approaches the tapping opening, and then causes the excitation control means to move the moving magnetic field. 2. The steel output of the refining equipment according to claim 1, further comprising means for instructing the generation of the molten steel, detecting the outflow of the molten steel from the steel output port, and adjusting the inclination of the furnace according to the detected steel output flow rate. apparatus. 3. The tapping control means responds to the tapping start instruction, adjusts the inclination of the furnace until the position of the upper surface of the slag in the furnace approaches the tapping opening, and then causes the excitation control means to move the moving magnetic field. Of the refining equipment according to claim 1, further comprising means for instructing the generation of molten steel and detecting the outflow of molten steel from the tapping mouth, and then adjusting the strength of the moving magnetic field according to the detected tapping flow rate. Tapping equipment. 4. A plate-shaped member made of a magnetic material is installed along the outer peripheral wall of the furnace belly of the furnace, between the furnace and the exciting means.
The tapping device of the refining equipment according to claim 1.