JP3697572B2 - Red smoke prevention device when handling molten metal - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a method for preventing red smoke at the time of molten metal handling so as to prevent red smoke generated when molten metal such as hot metal or molten steel is poured into a receiver.
[0002]
[Prior art]
Conventional methods for preventing red smoke during molten metal handling include, for example, Japanese Patent Application Laid-Open No. 49-9405 (hereinafter referred to as a first conventional example) and Japanese Patent Application Laid-Open No. 9-96492 (hereinafter referred to as a second conventional example). ) Are listed.
In the first conventional example, when the hot metal is discharged into the receiver, the container is filled with an inert gas or spray water in advance, and then the hot metal is discharged into the container. Is disclosed.
[0003]
In addition, in the second conventional example, when pouring hot metal into the container, the inert gas is blown into the container prior to the pouring to eliminate the air and to inactivate the atmosphere in the container. And the red smoke prevention method at the time of hot metal handling which was made to perform pouring while supplying an inert gas in a container after that is indicated.
[0004]
[Problems to be solved by the invention]
However, when an inert gas is used as in the first conventional example and the second conventional example, in order to obtain a red smoke suppression effect, for example, in a ladle scale of 150 tons, about 20,000 Nm ³ / H inert gas is required, which is not practical due to the increased cost, and it is difficult to stably supply the inert gas due to the instantaneous use of the inert gas in large quantities, which is possible for experiments. However, there is an unresolved issue that implementation on a factory scale is impossible.
[0005]
In addition, as in the first conventional example, it is more realistic to use spray water instead of inert gas because of the effect of suppressing red smoke and economy, but a steam explosion occurs due to contact between water and a high-temperature melt. There is an unresolved problem that there is a fear that safe operation cannot be secured. Therefore, the present invention has been made paying attention to the above-mentioned unsolved problems of the conventional example, and when water is used to suppress the generation of red smoke, the occurrence of a steam explosion is reliably prevented while preventing red smoke. It aims at providing the red smoke prevention apparatus at the time of the molten metal handling which can suppress generation | occurrence | production of smoke.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the apparatus for preventing red smoke at the time of molten metal handling according to claim 1 includes a dust collection hood and a water spray mechanism disposed on a traverse frame of a movable carriage having traveling wheels. An apparatus for preventing red smoke during handling of molten metal, wherein the dust collecting hood includes a central hood portion fixed to the traverse frame, and a rotating hood protruding in the left-right direction from the central hood portion. Further, the water spray mechanism includes a rotating shaft that extends in the front-rear direction on the transverse frame and is rotatably disposed by a pair of front and rear bearings, and an outer periphery that is fixed at one end to the rotating shaft and extends downward. A cylinder whose portion is covered with a heat insulating plate, two front and rear headers provided with a plurality of spray nozzles disposed at the tip of the cylinder, a water supply pipe for supplying water to the header, and an end of the water supply pipe Connected to the part through a joint. A sprayable hose and a rotation mechanism for rotating the rotation shaft are provided, and the spray nozzle is set so that water spray is performed covering the entire width direction of the molten iron flow flowing down from the kneading vehicle. In addition, a water supply system connected to a water supply source and a purge system water supply control unit connected to a gas source connected to the water supply system are connected to the water supply pipe .
[0007]
In the first aspect of the present invention, a dust collecting hood having a central hood portion and a rotating hood portion protruding in the left-right direction from the central hood portion on the transverse frame, and a rotating shaft rotated by a rotating mechanism. A water spray mechanism having two sets of front and rear headers provided with a plurality of spray nozzles at the tip of the cylinder fixed to the cylinder is disposed, so that the chaotic vehicle can be moved on either side by moving the traversing frame. Even if it exists, it is possible to cover all of the width direction of the hot metal flow flowing down from the kneading car with one set of dust collecting hood and water spray mechanism, and to prevent the generation of red smoke. .
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 and 2 are a front view and a side view showing a raw material yard of a steelmaking factory to which the present invention can be applied, in which 1A and 1B arrive at chaotic vehicles 2A and 2B that contain hot metal from a blast furnace. A pair of left and right platforms, and hot metal ladles 5A and 5B as receiving devices having a traveling carriage 4 in which molten metal is poured from the kneading wheels 2A and 2B in a recess 3 formed between the platforms 1A and 1B. Is formed.
[0010]
In addition, left and right guide rails 7F and 7R are laid on the upper ends of the front and rear side walls forming the recess 3, and the hood cart 8 is arranged so as to be movable in the left and right directions by being guided by these guide rails 7F and 7R. . The hood carriage 8 includes machine frames 10F and 10R having traveling wheels 9 engaged with the guide rails 7F and 7R, a transverse frame 11 bridged between the machine frames 9F and 9R, and the transverse frame 11. The dust collecting hood 12 and the water spray mechanism 13 are configured.
[0011]
Here, the dust collection hood 12 includes a central hood portion 12a fixed to the traverse frame 11, and rotating hood portions 12b and 12c projecting in the left-right direction from the central hood portion 11a. When the hot metal ladle 5A on the platform 1A side is at a position facing the upper side from above, the rotating hood 12b is in a horizontal state to cover the upper part of the chaotic wheel 2A, and the rotating hood 12c is inclined to the lower right to form the hot metal ladle. When dust generated in 5A is collected and the hood cart 8 is in a position facing the hot metal ladle 5B on the platform hole 1B side from above, the rotating hood 12b is inclined leftward and generated in the hot metal ladle 5B. Dust is collected, and the rotating hood 12c covers the upper part of the chaotic wheel 2B.
[0012]
As shown in FIGS. 3 to 5, the water spray mechanism 13 extends in the front-rear direction to a position near the center of the traversing frame 11 and is pivotally disposed by a pair of front and rear bearings 14. A rectangular tube 16 whose one end is fixed to the rotating shaft 15 and whose outer peripheral portion extends downward is covered with a heat insulating plate, and a plurality of spray nozzles 17a to 17f disposed at the tip of the rectangular tube 16 are provided. Two sets of front and rear headers 18A and 18B provided, and a water supply pipe 19A that passes through the rectangular cylinder 16 that supplies water to the headers 18A and 18B, is exposed to the outside in the middle, and is disposed along the rotary shaft 15. 19B, flexible hoses 20A and 20B connected to the ends of the water supply pipes 19A and 19B via joints, and a rotating mechanism 21 that rotates the rotating shaft 15.
[0013]
Here, the header 18A is disposed in a state where the spray nozzles 17a to 17f provided on the header 18A are inclined 145 ° counterclockwise with respect to the central axis of the rectangular tube body 16, as shown in FIG. 18B is arranged in a state where spray nozzles 17a to 17f provided thereon are inclined by 130 ° clockwise with respect to the central axis of the rectangular tube body 16.
[0014]
Each of the spray nozzles 17a to 17f employs a full cone nozzle having a circular spray pattern and an even flow distribution, a standard pressure of 2 kg / cm ² , an injection angle of 80 °, and an injection amount of 28. (L / min), the average particle size is set to about 740 μm, and water spraying is performed so as to cover all of the width direction of the molten iron flow flowing down from the kneading wheels 2A and 2B.
[0015]
Further, as shown in FIGS. 3 and 4, the rotation mechanism 21 includes a rotation lever 22 fixed to the right end of the rotation shaft 15, and a power cylinder 23 having one end rotatably attached to the transverse frame 11. The piston rod 24 of the power cylinder 23 is rotatably attached to the tip of the rotation lever 22 and the extension amount of the piston rod 24 is controlled so that the rectangular tube body 16 is shown by a solid line in FIG. Inclined position for hot metal ladle 5A inclined about 5 ° counterclockwise with respect to the vertical line, for example, inclined position for hot metal ladle 5B inclined about 20 ° clockwise with respect to the vertical line shown in FIG. In FIG. 1, the rotation is controlled between a maintenance position inclined about 70 ° counterclockwise with respect to a vertical line shown by a two-dot chain line.
[0016]
Furthermore, the other ends of the flexible hoses 20A and 20B connected to the headers 18A and 18B are connected to a water supply control unit 30 provided on the ground as shown in FIG. This water supply control unit 31 includes a pump 33 whose suction side is connected to a water supply source via a shutoff valve 32, a flow rate adjusting valve 34, a damper valve 35, an electromagnetic on-off valve 36, which are sequentially connected to the protruding side of the pump 33, A water supply system 38 having a pressure control valve 37, a flow control valve 39 connected to a nitrogen gas source as an inert gas, and a purge system 41 including an electromagnetic opening / closing valve 40, and shutting off the water supply system 38. The output side of the valve 37 and the output side of the electromagnetic open / close valve 40 of the purge system 41 are connected to each other, and the connecting end is branched and connected to the flexible hoses 20A and 20B via the electromagnetic open / close valves 42 and 43, respectively. .
[0017]
And the pump 33 of the water supply control unit 31, the flow control valves 34 and 39, and the electromagnetic on-off valves 36, 40, 42 and 43 are controlled by the controller 44. The controller 44 is connected to a water supply switch 45 for supplying water on the header 18A side operated by an operator, and a water supply switch 46 for supplying water on the header 18B side, and from the chaotic vehicle 2A on the platform 1A side. Prior to starting the pouring of the hot pot 5A, when the operator turns on the water supply switch 45, first, nitrogen gas is supplied to the header 18A and sprayed from the spray nozzles 17a to 17f. Water supply is started after a sufficient time has passed for discharging from the spray nozzles 17a to 17f, and when the water supply reaches the spray nozzles 17a to 17f, fine water mist is generated from the spray nozzles 17a to 17f. When enough time has passed for this water mist to fill the receiving pans 5A, 5B, After pouring hot water from the carts 2A and 2B to the receiving pans 5A and 5B, after a predetermined time has elapsed, the supply of nitrogen gas is shut off and the spraying state is shifted to water only, and then the hot metal ladle As will be described later, the flow rate and pressure of the feed water are controlled so that the oxygen concentration in the hot metal ladle 5A during pouring of hot metal to 5A is 12% or less, preferably 8% or less.
[0018]
Thereafter, at the end of water supply, after supplying a nitrogen gas in the water supply state and after a predetermined time sufficient for the nitrogen gas to reach the spray nozzles 17a to 17f, the water supply is stopped, and the flexible hose 20A, the water supply pipe 19A and the header are stopped. The supply of nitrogen gas is stopped after a sufficient time has passed to completely eliminate the water in 18A.
Next, the operation of the above embodiment will be described with reference to the flowchart of FIG. 6 showing an example of a water supply control processing procedure executed by the controller 44 of the water supply control unit 31.
[0019]
In this water supply control process, first, in step S1, it is determined whether or not the water supply switch 45 for supplying water to the header 18A side is turned on. 40 and 42 are controlled to be in an open state, and then the process proceeds to step S3 to determine whether or not a predetermined time T1 required until nitrogen gas is discharged from the tip of the spray nozzles 17a to 17f in the header 18A. When the predetermined time T1 has not elapsed, the process waits until the predetermined time T1 has elapsed. When the predetermined time T1 has elapsed, the process proceeds to step S4, the pump 33 is driven, and the electromagnetic on-off valve 36 is controlled to be opened. The process proceeds to step S5.
[0020]
In this step S5, water supply is started and water is discharged from the tips of the spray nozzles 17a to 17f in the header 18A, so that water mist finely divided is generated from these spray nozzles 17a to 17f, and this water mist is received in the receiving pan. It is determined whether or not a predetermined time T2 that is sufficient to start filling the molten metal 5A and start pouring molten metal from the kneading vehicle 2A has elapsed, and when the predetermined time T2 has not elapsed, the predetermined time T2 has elapsed. When the predetermined time T2 has elapsed, the process proceeds to step S6, and the electromagnetic on-off valve 40 is controlled to be closed, and then the process proceeds to step S7.
[0021]
In this step S7, the feed water flow rate and feed water pressure are controlled such that the oxygen concentration in the hot metal ladle 5A is the target water spray amount Q ^* (l / min) that is 12% or less, preferably 8% or less.
Here, when hot metal is poured into the hot metal ladle 5A, as shown in FIG. 7 (b), a downward flow of outside air is generated on the inner peripheral surface side of the hot metal pan 5A, and this downward flow is As shown in FIG. 7 (b), this updraft occupies 80% of the cross-sectional area of the hot metal ladle 5A. Since this updraft contacts the hot metal to be poured, red smoke is generated.
[0022]
This red smoke generation mechanism is focused on the fact that the amount of red smoke generated is less when pouring molten steel than when pouring molten steel and when pouring molten steel. It was confirmed that it was due to the same bubble burst phenomenon as the dust generation mechanism. That is, splashing particles having a particle size of about 100 μm including iron Fe and carbon C are generated during molten metal pouring, and the oxygen affinity of carbon C in the splashing particles is strong and oxidizes before iron Fe. By gasifying as carbon monoxide CO, the splashing particles suddenly expand in volume, exploding without being able to withstand this volume expansion, and becoming finer iron Fe particles of about several μm. It was confirmed that this oxidized to red smoke. As a result, it has been found that in order to suppress red smoke, it is sufficient to control the oxygen concentration so that the refined iron Fe particles are not oxidized.
[0023]
Accordingly, since the inactive state in the hot metal ladle 5A changes due to the air entering from outside the system due to convection in the hot metal ladle 5A, the oxygen concentration in the hot metal ladle 5A is maintained at 12% or less by water spraying.
That is, as a result of an experiment on the relationship between the oxygen concentration (%) during molten metal pouring using a 60-ton ladle and the amount of dust generated (g / Nm ³ ), as shown in FIG. When the concentration is taken and the vertical axis indicates the dust concentration, when the oxygen concentration exceeds 12%, the generated dust concentration shows a high value of 6 to 11 g / Nm ³ and a large amount of red smoke is generated. However, when the oxygen concentration is 12% or less, the generated dust concentration is 2 g / Nm ³ or less, the generation of red smoke can be suppressed to about 1/3 or less, and the oxygen concentration is 8% or less. It was found that the dust concentration becomes approximately 0 g / Nm ³ and the generation of red smoke can be reliably prevented.
[0024]
Therefore, by controlling the oxygen concentration in the hot metal ladle 5A to 12% or less, the generation of red smoke can be suppressed, but the spray nozzles 17a to 17f for maintaining the oxygen concentration at 12% or less. The target water spray amount Q ^* in FIG. 5 is: D (m) for the inner diameter of the hot metal ladle 5A, v (m / s) for the rising flow velocity from the hot metal ladle 5A, and k for the estimation determining constant It can be calculated by the following equation (2).
[0025]
Q ^* ≧ kπD ² v (2)
A target water supply amount QW ^* and a target water supply pressure PW ^* are set so as to maintain the target water spray amount Q ^* , and the flow rate of the water supply system 38 is set by a flow meter 47 arranged on the outlet side of the pressure control valve 37. The pressure is detected by a pressure gauge 48 disposed on the outlet side of the pressure control valve 37 in the same manner, and the flow rate detection value Q and the pressure detection value P maintain the target water supply amount QW ^* and the target water supply pressure PW ^* . Feedback control.
[0026]
Next, the process proceeds to step S8, where it is determined whether or not the water supply switch 45 is in an off state. When the on state continues, the process returns to step S7, and when it is in the off state, the process proceeds to step S9. Then, the electromagnetic on-off valve 40 is opened, and supply of nitrogen gas is started. Then, the process proceeds to step S10, where it is determined whether or not a predetermined time T3 of about several seconds has elapsed, and the predetermined time T3 has elapsed. If not, the process waits until the elapsed time T3 elapses, and when the elapsed time T3 elapses, the process proceeds to step S11, the electromagnetic on-off valve 36 is controlled to be closed, and then the process proceeds to step S12 where the flexible hose 20A, the water supply pipe 19A, the header It is determined whether or not a predetermined time T4 required for completely discharging the water inside 18A has elapsed, and this elapses when the predetermined time T4 has not elapsed. Wait, when the predetermined time T4 has elapsed the process proceeds to step S13, returns the solenoid valve 42 from the control to the closed state to the step S1.
[0027]
On the other hand, if the determination result in step S1 is that the water supply switch 45 is in the OFF state, the process proceeds to step S14, and whether or not the water supply switch 46 that starts water supply to the hot metal ladle 5B is in the ON state. If this is in the off state, the process returns to step S1, and if it is in the on state, the process proceeds to steps S15 to S26, and the electromagnetic on / off valve 43 is controlled to be opened instead of the electromagnetic on / off valve 42 in step S15. In step S26, the electromagnetic on / off valve 43 is controlled to be closed instead of the electromagnetic on / off valve 42, and step S2 described above is performed except that it is determined in step S21 whether or not the water supply switch 46 is in an off state. After performing the same process as the process of ~ S13, the process returns to step S1.
[0028]
Therefore, when the molten metal is not poured from the kneading wheels 2A and 2B to the hot metal ladles 5A and 5B, both the water supply switches 45 and 46 are in the off state. Therefore, in the water supply control process of FIG. S1 and step S14 are repeated, the electromagnetic on-off valves 36, 40, 42 and 43 are closed, and the supply of water and nitrogen gas to the spray nozzles 17a to 17f of the headers 18A and 18B is stopped. .
[0029]
In this state, when the kneading vehicle 2A arrives at the platform 1A and the molten metal is poured from the kneading vehicle 2A into the hot metal ladle 5A, first, the hood cart 8 is moved to a position above the hot metal ladle 5A, By rotating the rotation lever 24 to the position indicated by the solid line in FIG. 4 by the rotation mechanism 21 of the spray mechanism 13, the spray nozzles 17a to 17f of the header 18A enter the molten metal flow path as shown by the solid line in FIG. It will be in the state which opposes with the inclination-angle of 60 degrees from a horizontal surface.
[0030]
In this state, the operator turns on the water supply switch 45 before tilting the kneading wheel 2A to start pouring molten metal into the hot metal ladle 5A. Accordingly, in the water supply control process of FIG. 6, the process proceeds from step S1 to step S2, and first, nitrogen gas is injected from the spray nozzles 17a to 17f of the header 18A, and in this state, the pump 33 is driven to rotate, The electromagnetic on-off valve 36 is opened, and water supply to the spray nozzles 17a to 17f of the header 18 is started. At this time, since nitrogen gas has been previously injected into the spray nozzles 17a to 17f, even if this injection gas and water are mixed and the discharge pressure of the pump 33 is low immediately after the start of water supply, water having a small particle size is used. It becomes a mist state and is sprayed and filled in the hot metal ladle 5A. By the way, when water supply is started directly without spraying nitrogen gas at the start of water spraying with the spray nozzles 17a to 17f, the discharge pressure of the pump 33 is low, so that the spray nozzles 17a to 17f are not atomized and are shower-like. There is a risk of dripping, and the water droplets reach the bottom of the hot metal ladle 5A without evaporating. In this state, hot metal is poured or drops of water fall into the shape of the accumulated hot metal, causing a steam explosion. In this embodiment, water mist is generated even at the start of water supply, and it is possible to reliably prevent dripping. Therefore, steam explosion can be avoided and safe operation should be performed. Can do.
[0031]
When hot metal is poured into the hot metal ladle 5A in a state where the hot metal pan 5A is filled with water mist, water mist sprayed from the spray nozzles 17a to 17f is directly sprayed on the hot metal, and thereafter After a predetermined time T2, the electromagnetic on-off valve 40 is closed, and only water is supplied to the spray nozzles 17a to 17f of the header 18A. The spray nozzles 17a to 17f are sprayed with a particle size of about 740 μm. . For this reason, since the spray water sprayed directly contacts the molten iron flow falling from the kneading wheel 2A, it is instantly steamed, and water particles are jetted obliquely downward from the spray nozzles 17a to 17f. The generated water vapor is reliably drawn into the hot metal ladle 5A by the descending airflow formed by the hot metal flow, and the hot metal ladle 5A is filled with water vapor.
[0032]
The flow rate and pressure of the water supply system 38 are feedback-controlled so that the spray amount at this time becomes the target water spray amount Q ^* .
Thus, the oxygen concentration in the hot metal ladle 5A is reduced to 12% or less by controlling the water spray amount sprayed from the spray nozzles 17a to 17f to the hot metal to the target water spray amount Q ^* . At this time, if the oxygen concentration is controlled within the range of 12% or less and exceeding 8%, the amount of red smoke generated should be reduced by 1/3 or more compared to the amount of red smoke generated when the oxygen concentration exceeds 12%. Further, when the oxygen concentration is controlled to 8% or less, generation of red smoke can be surely prevented.
[0033]
Thereafter, when the hot metal pouring is completed, the operator switches the water supply switch 45 to the OFF state, whereby the electromagnetic on-off valve 40 is first controlled to be in the open state, and nitrogen gas is supplied to the spray nozzles 17a to 17f of the header 18A. When the nitrogen gas is discharged from the spray nozzles 17a to 17f, water mist having a small particle diameter is sprayed as described above, and in this state, the electromagnetic on-off valve 36 is controlled to be closed, Water supply is stopped.
[0034]
As a result, only the nitrogen gas is supplied to the flexible hose 20A, the water supply pipe 19A, and the header 18A to be in a purge state, and all the remaining moisture is discharged from the spray nozzles 17a to 17f, and the electromagnetic is generated when the purge is completed. By closing the on-off valve 42 and subsequently closing the electromagnetic on-off valve 40, the supply of nitrogen gas to the header 18A is also shut off. For this reason, it is possible to prevent drooling at the end of the water supply and to stop the water supply safely, and there is no water droplets remaining in the water supply path at the start of the next spraying. It can be performed.
[0035]
Further, since nitrogen gas, which is an inert gas, is used as the purge gas, the nitrogen gas accumulates at the bottom of the hot metal ladle 5A or 5B during the purge, so that the oxygen in the hot metal ladle 5A is also collected by this accumulated nitrogen gas. There is an effect of reducing the concentration.
In addition, when pouring hot metal from the kneading wheel 2B to the hot metal ladle 5B on the platform 1B side, the hood cart 8 is moved to a position facing the hot metal ladle 5B as shown in FIG. By rotating the rectangular tube 16 in the clockwise direction as viewed in FIG. 4 by the rotation mechanism 21 of the water spray mechanism 13, the spray nozzles 17a to 17f of the header 18B are placed on a horizontal plane as shown by the chain line in FIG. In contrast, the oxygen concentration in the hot metal ladle 5B is preferably 12% or less by facing the hot metal flow path from the kneading wheel 2B in a state inclined by 60 ° and performing water supply control in the same manner as described above. Can be controlled to 8% or less to suppress or prevent the generation of red smoke.
[0037]
Moreover, in the said embodiment, about the case where the water spray mechanism 13 is arrange | positioned in the food cart 8, and red smoke generation | occurrence | production at the time of the pouring to the hot metal ladle 5A and 5B from the kneading vehicles 2A and 2B is prevented. Although explained, it is not limited to this, You may make it provide a water spray mechanism separately.
Furthermore, in the above-described embodiment, before the molten metal is started to be poured from the kneading wheels 2A and 2B, the atomized water mist obtained by mixing water and the purge gas from the spray nozzles 17a to 17f of the water spray mechanism 13 is molten. The case where the oxygen concentration is reduced by spraying the hot pots 5A and 5B and filling the hot metal hot pots 5A and 5B with water mist to prevent the generation of red smoke has been described. Instead, the water mist may be sprayed into the hot metal flow at the same time as or immediately before the start of hot metal pouring.
[0038]
Furthermore, in the above embodiment, the target spray amount Q ^* of the headers 18A and 18B is set so that the oxygen concentration in the hot metal ladles 5A and 5B is 12% or less, preferably 8% or less, and this target spray amount Q ^* is maintained. As described above, the case where the pressure and flow rate of the water supply system 38 are controlled has been described. However, the present invention is not limited to this, and the oxygen concentration in the hot metal ladles 5A and 5B is directly measured with an oxygen concentration meter. The flow rate and pressure of the water supply meter 38 may be feedback controlled so that the oxygen concentration is 12% or less, preferably 8% or less.
[0039]
Moreover, in the said embodiment, although the case where the water supply system 38 and the purge system 41 were automatically controlled by operation of the water supply switch 45,46 of an operator was demonstrated, it is not limited to this, From chaotic vehicles 2A, 2B The start of pouring of molten iron may be detected and the oil supply system 38 and the purge system 41 may be automatically controlled, and the water supply system 38 and the purge system 41 may be controlled manually by the operator. May be.
[0040]
Furthermore, in the above-described embodiment, the case where the electromagnetic on-off valve 36 is opened and controlled immediately after the pump 33 of the water supply system 38 is driven has been described. However, the present invention is not limited to this. A valve 37 is provided on the upstream side of the electromagnetic opening / closing valve 36, and a flow rate system 47 and a pressure gauge 48 are disposed between the pressure control valve 37 and the electromagnetic opening / closing valve 36, so that the feed water pressure measured by the pressure gauge 48 is increased. By starting the water supply by controlling the electromagnetic on-off valve 36 to the open state when the predetermined set value or more is reached, it is possible to more reliably prevent dripping at the start of water supply to the water spray mechanism 13.
[0041]
【The invention's effect】
As described above, according to the first aspect of the present invention, the dust collecting hood having the central hood portion and the rotating hood portion protruding in the left-right direction from the central hood portion on the traversing frame, and the rotating mechanism A water spray mechanism having two sets of front and rear headers provided with a plurality of spray nozzles at the tip of a cylindrical body fixed to a rotating shaft to be rotated is disposed. Even if there is a chaotic vehicle on either side, a set of dust collecting hood and water spray mechanism can cover all the width direction of the hot metal flow flowing down from the chaotic vehicle and perform water spraying . The effect that generation | occurrence | production can be prevented is acquired.
[Brief description of the drawings]
FIG. 1 is a front view showing an embodiment in which the present invention is applied to a raw material yard of a steelmaking factory.
FIG. 2 is a plan view of FIG.
FIG. 3 is a front view showing an example of a water spray mechanism.
4 is a right side view of FIG. 3. FIG.
FIG. 5 is a system diagram showing a water supply system of a water spray mechanism.
FIG. 6 is a flowchart illustrating an example of a water supply control process.
FIG. 7 is an explanatory diagram for explaining a convection state in a hot metal ladle.
FIG. 8 is a characteristic diagram showing experimental results of oxygen concentration and dust concentration.
[Explanation of symbols]
2A, 2B Chaotic wheel 5A, 5B Hot metal ladle 8 Hood bogie 13 Water spray mechanism 16 Square cylinder 18A, 18B Header 17a-17f Spray nozzle 19A, 19B Water supply pipe 20A, 20B Flexible hose 21 Rotating mechanism 31 Water supply control unit 33 Pump 34 Flow control valve 36 Electromagnetic on-off valve 37 Pressure control valve 40, 42, 43 Electromagnetic on-off valve 44 Controller 45, 46 Water supply switch 47 Flow meter 48 Pressure gauge

Claims (1)

A red smoke prevention device at the time of molten metal handling composed of a dust collection hood and a water spray mechanism arranged on a traversing frame of a movable carriage having traveling wheels,
The dust collection hood includes a central hood portion fixed to the traversing frame, and a rotating hood protruding in the left-right direction from the central hood portion, and the water spray mechanism extends to the traversing frame in the front-rear direction. A rotating shaft rotatably disposed by a pair of front and rear bearings, a cylindrical body having one end fixed to the rotating shaft and extending downward and covered with a heat insulating plate, Two sets of front and rear headers provided with a plurality of spray nozzles disposed at the tip, a water supply pipe for supplying water to the headers, a flexible hose connected to the end of the water supply pipe via a joint, and a rotating shaft And the spray nozzle is set to cover all of the width direction of the hot metal flow flowing down from the kneading wheel so that water spraying is performed, and the water supply pipe has Water supply system connected to a water supply source and the water supply Red smoke prevention device at the time the molten metal handling, characterized in that the water supply control unit of the connected purge system connected to the gas source is connected to.

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