JP2013202631A - Secondary cooling device for continuous casting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a secondary cooling device for continuous casting apparatus that cools a cast slab according to a change in cast slab width, without lowering spray efficiency, and uniformly.SOLUTION: A secondary cooling device 1 for continuous casting apparatus 7 is configured to support a cast slab 5 between a plurality of support rolls 3 from above and below and to draw the cast slab 5 out of a mold 15 continuously for casting. The secondary cooling device 1 for the continuous casting apparatus 7 includes three or more spray nozzles (a first spray nozzle 9a to a fourth spray nozzle 9d) arranged in a gap between the plurality of support rolls 3 arranged in the drawing-out direction of the cast slab 5, in a cast slab width direction, and a spray nozzle moving device 11 which moves the first spray nozzle 9a to the fourth spray nozzle 9d in the cast slab width direction while maintaining the ratio of distances among the first spray nozzle 9a to the fourth spray nozzle 9d.

Description

  The present invention relates to a secondary cooling device for continuous casting equipment.

Secondary cooling of continuous casting equipment is a process of cooling and solidifying the slab, and its cooling rate and temperature distribution are important techniques that lead to quality defects in the slab.
In the past, secondary cooling was spray-cooled only with water, but recently, with the aim of uniform cooling, it has been mainly performed by two-fluid spray (mist spray) with compressed air and water.

The secondary cooling device of the continuous casting facility, which is a device for performing the secondary cooling as described above, is required to spray uniformly in the slab width direction between the support rolls for the purpose of uniform cooling.
However, particularly in the edge portion of the slab, the coolant sprayed on the upper and lower surfaces of the slab wraps around the plate thickness side of the edge portion and cools the edge portion also from the side. When the temperature of the edge portion is too low, when the slab cast into a large arc shape is returned straight, the edge portion will be cracked so that the edge portion can be managed not to be overcooled. is necessary.

Further, since the slab width is changed according to demand, the secondary cooling device is required to be able to change the cooling range in accordance with the change of the slab width.
As a secondary cooling device for responding to the above request, for example, there is one disclosed in Patent Document 1.
The secondary cooling device disclosed in Patent Document 1 describes a spray nozzle arranged so as to face the slab surface, and the spray nozzle in a direction perpendicular to the slab traveling direction along an outer line of a specific injection angle. A nozzle moving device that moves in a direction toward or away from the slab, and a nozzle position detector provided in the nozzle moving device for disposing the spray nozzle at an arbitrary position with respect to the slab. "Characteristic" (see claim of Patent Document 1).

Japanese Patent Laid-Open No. 61-226152

The secondary cooling device described in Patent Document 1 adjusts the spray width by moving the spray nozzle in the direction approaching or leaving the slab along the outer line of the specific injection angle.
The movement direction of the spray nozzle is moved along the outer line of the specific injection angle in order to prevent the spray range from overlapping and gaps with the movement of the spray nozzle.
However, it is only when the spray nozzles at both ends in the slab width direction are moved that the overlap or gap does not occur in the spray range. Therefore, Patent Document 1 discloses a case where two spray nozzles are provided in the slab width direction, or a case where only the spray nozzles arranged on both sides of the slab width direction are movable and the others are fixed. Yes.

  However, if the movement of the two spray nozzles arranged in the slab width direction is to cope with the change in the slab width, the vertical movement distance of the spray nozzle becomes large, for example, a spray installed on the upper side of the slab. In the nozzle, the spray nozzle may move to a position higher than the height of the support roll. In such a case, the injected refrigerant is blocked by the support roll, and a slight gap between the front and rear support rolls is generated. Since the refrigerant is injected from the effective spray zone, the effective spray zone is greatly reduced, resulting in a decrease in spray efficiency.

In addition, the spray nozzle installed on the lower side of the slab has the following problems in addition to the problem of the decrease in spray efficiency. In the spray nozzle installed on the upper side of the slab, the coolant blocked by the support roll becomes water droplets, but such water droplets can fall on the slab through the support roll and cool the slab. it can.
However, in the spray nozzle installed on the lower side of the slab, even if the coolant blocked by the support roll becomes water droplets, it just falls and does not contribute to cooling the slab. Therefore, there exists a problem that cooling capacity will be impaired further than the spray nozzle installed in the upper side of slab.
In addition, the secondary cooling device disclosed in Patent Document 1 moves the spray nozzle in a direction approaching or moving away from the slab along the outer line of the specific injection angle, so that there is a large space up and down across the slab. Although necessary, there is also a problem that it cannot be applied when such a space cannot be secured.

  The present invention has been made to solve such a problem, and a secondary cooling device for continuous casting equipment that uniformly cools a slab without reducing spray efficiency in accordance with a change in slab width. The purpose is to get.

(1) The secondary cooling device of the continuous casting equipment according to the present invention is the above-described continuous casting equipment that supports a plurality of support rolls so that the upper and lower sides of the slab are sandwiched and continuously pulls out the slab from the mold and performs casting. A secondary cooling device for secondary cooling of the slab,
Each of the sprays while maintaining the ratio of the distance between the spray nozzles arranged in the gap width direction between the plurality of support rolls arranged in the drawing direction of the slab and the adjacent spray nozzles. And a spray nozzle moving device for moving the nozzle in the slab width direction.

(2) Further, in the above (1), the spray nozzle moving device moves the spray nozzle in parallel to the surface of the slab.

(3) In the above (1), the spray nozzle moving device is
When the spray nozzle is moved in a direction in which the ratio of the distance between the adjacent spray nozzles is increased, the spray nozzle is also moved in a direction in which the distance between the spray nozzle and the slab is separated,
When the spray nozzle is moved in a direction in which the ratio of the distance between the adjacent spray nozzles is reduced, the spray nozzle is also moved in a direction in which the distance between the spray nozzle and the slab approaches. It is.

(4) Moreover, in the above-mentioned one of (1) to (3), the spray nozzle moving device is arranged at equal intervals in the slab width direction and is supplied with three or more header tubes. And a header pipe moving device that supports the header pipe and moves the header pipes in the slab width direction while maintaining the ratio of the distance between the adjacent header pipes.
The spray nozzle is attached to the header pipe via a branch pipe.

(5) Moreover, in the above-described (4), the header pipe moving device supports the same number of header pipes arranged on both sides with the center of the slab width direction as a boundary. The ratio of the moving distance of the header pipe is proportional to the ratio of the distance from the center of the slab width direction, and the direction of movement between the one arranged on the same side and the other side of the slab width direction center Is moved in the opposite direction.

(6) In the above (4) or (5), the header pipe moving device moves the header pipe in a direction parallel to the slab surface.

(7) Further, in the above (4) or (5), the header pipe moving device supports the header pipe via a connecting rod,
When moving the header pipe in a direction in which the ratio of the distance between the adjacent header pipes is increased, the header pipe is also moved in a direction in which the distance between the header pipe and the cast piece is increased,
When the header pipe is moved in a direction in which the ratio of the distance between the adjacent headers is reduced, the header pipe is also moved in a direction in which the distance between the header pipe and the cast piece approaches. is there.

  In the present invention, the secondary cooling device is a secondary cooling device of the continuous casting facility according to the present invention. The secondary cooling device is supported by sandwiching the upper and lower sides of the slab with a plurality of support rolls, and continuously casting the slab from the mold. A secondary cooling device that performs secondary cooling of the slab in a continuous casting facility that is arranged in the gap between the plurality of support rolls arranged in the drawing direction of the slab in the slab width direction. The spray nozzle and a spray nozzle moving device that moves each spray nozzle in the slab width direction while maintaining the ratio of the distance between adjacent spray nozzles. Thus, the slab can be cooled uniformly without reducing the spray efficiency.

It is an elevational view including the partial cross section of the secondary cooling device which concerns on Embodiment 1 of this invention. It is a top view containing the partial cross section of the secondary cooling device of FIG. It is explanatory drawing explaining a continuous casting installation. It is explanatory drawing explaining operation | movement of the secondary cooling device of FIG. 1, Comprising: It is a figure explaining the case where a wide slab is cooled. It is explanatory drawing explaining operation | movement of the secondary cooling device of FIG. 1, Comprising: It is a figure explaining the case where a narrow slab is cooled. It is explanatory drawing explaining the control apparatus of the secondary cooling device described in FIG. It is explanatory drawing explaining the flow of the process which controls a spray angle. It is explanatory drawing explaining the other aspect of the secondary cooling device which concerns on Embodiment 1 of this invention, Comprising: It is a top view including a partial cross section. It is a top view including the partial cross section of the secondary cooling device which concerns on Embodiment 2 of this invention. It is an elevational view including a partial cross section of the secondary cooling device according to Embodiment 3 of the present invention. It is explanatory drawing explaining operation | movement of the secondary cooling device of FIG. 10, Comprising: It is a figure explaining the case where a wide slab is cooled. It is a figure explaining the spray range of the secondary cooling device of FIG. It is the figure which extracted and expanded a part of FIG. 12 for more detailed description. It is a figure explaining the influence on the cooling of the secondary cooling device of FIG. 10 (the 1). It is a figure explaining the influence on the cooling of the secondary cooling device of FIG. 10 (the 2). It is explanatory drawing of the other aspect of the secondary cooling device which concerns on Embodiment 3 of this invention, Comprising: It is a top view including a partial cross section.

<Embodiment 1>
As shown in FIG. 1, the secondary cooling device 1 according to the embodiment of the present invention supports the slab 5 so that the upper and lower sides are sandwiched by a plurality of support rolls 3 and continuously pulls out the slab 5 from the mold. The secondary cooling device 1 of the continuous casting equipment 7 (see FIG. 3) for casting,
A plurality of spray nozzles (first spray nozzle 9a, second spray nozzle 9b, third from the right side of the figure in order from the right side of the figure) in the gap between the plurality of support rolls 3 arranged in the drawing direction of the slab 5 A spray nozzle 9c and a fourth spray nozzle 9d), and a spray nozzle moving device 11 that moves adjacent spray nozzles in the slab width direction while maintaining the ratio of the distance between the first spray nozzle 9a to the fourth spray nozzle 9d. It is characterized by having.

Since secondary cooling device 1 concerning an embodiment of the invention is provided in continuous casting equipment 7, before explaining details of secondary cooling device 1, continuous casting equipment 7 is outlined.
As shown in FIG. 3, the continuous casting equipment 7 continuously draws the molten steel 17 supplied from the tundish 13 to the mold 15 as the slab 5 while being cooled by the mold 15, and the extracted slab 5 is a plurality of pieces. The support roll 3 is further pulled out to the downstream side so as to sandwich the upper and lower sides and cast.
A plurality of the support rolls 3 constitute a segment 19 with some of them as a set, and the secondary cooling device 1 is installed for each segment 19.
In FIG.1 and FIG.2, the example of the segment 19 of the support roll 3 and the secondary cooling device 1 installed in the said segment 19 are shown.

Next, each configuration of the secondary cooling device 1 will be described in detail with reference to FIGS. 1 and 2 as appropriate.
As shown in FIGS. 1 and 2, the secondary cooling device 1 is installed for each segment 19 of the continuous casting equipment 7 and cools the slab 5 passing through the segment 19.
Since the secondary cooling device 1 cools both the upper surface side and the lower surface side of the slab 5, the first spray nozzle 9 a to the fourth spray nozzle 9 d and the spray nozzle moving device 11 are provided on the upper surface side and the lower surface side of the slab 5. have. Since the first spray nozzle 9a to the fourth spray nozzle 9d and the spray nozzle moving device 11 arranged on the upper and lower surfaces are basically the same in configuration, the first spray nozzle 9a to the second spray nozzle 9a arranged on the upper side will be described below. The four spray nozzle 9d and the spray nozzle moving device 11 will be described as an example.

As described above, the secondary cooling device 1 includes the first spray nozzle 9a to the fourth spray disposed in the width direction of the slab 5 in the gaps between the plurality of support rolls 3 disposed in the drawing direction of the slab 5. A spray nozzle moving device 11 that moves the first spray nozzle 9a to the fourth spray nozzle 9d in the width direction of the slab 5 while maintaining the ratio of the distance between the nozzle 9d and the first spray nozzle 9a to the fourth spray nozzle 9d. And have.
Hereinafter, the spray nozzle and the spray nozzle moving device 11 will be described separately.

<Spray nozzle>
The first spray nozzle 9 a to the fourth spray nozzle 9 d are attached to the distal end of a branch pipe 21, which will be described later, which is a component of the spray nozzle moving device 11. ing. In the present embodiment, the first spray nozzle 9a to the fourth spray nozzle 9d are arranged in the gaps at equal intervals in the slab width direction.
The first spray nozzle 9a to the fourth spray nozzle 9d of the present embodiment are so-called two-fluid nozzles that mix refrigerant and compressed air to be misted and ejected. A refrigerant is supplied from the branch pipe 21 to the first spray nozzle 9a to the fourth spray nozzle 9d, and compressed air is supplied from an air supply pipe (not shown).

<Spray nozzle moving device>
The spray nozzle moving device 11 has a function of moving the first spray nozzle 9a to the fourth spray nozzle 9d in the width direction of the slab 5 while maintaining the ratio of the distance between the first spray nozzle 9a to the fourth spray nozzle 9d. Have.
In order to realize the above function, the spray nozzle moving device 11 is connected to the motor 23 with a speed reducer and the output shaft of the motor 23 with the speed reducer, and divides the driving force of the motor 23 with the speed reducer. 25, a connecting shaft 27 that is connected to the output side of the T-shaped miter gear box 25 to transmit the driving force, and an L-shaped miter gear box 29 that is connected to the connecting shaft 27 and branches the driving force. A rotating shaft 31 connected to the output side of the T-shaped miter gear box 25 and the L-shaped miter gear box 29 so as to extend in the slab width direction, and a predetermined interval between each rotating shaft 31. Sleeve members installed separately (a first sleeve member 33a, a second sleeve member 33b, a third sleeve member 33c, and a fourth sleeve member 3 in this order from the base end side of the rotating shaft 31). d), and header pipes fixed to the first sleeve member 33a to the fourth sleeve member 33d (first header pipe 35a, second header pipe 35b, third header pipe 35c and first header pipe 35a in order from the base end side of the rotating shaft 31). 4 header pipes 35d), one end of which is connected to the first header pipe 35a to the fourth header pipe 35d and the other end of which the first spray nozzle 9a to the fourth spray nozzle 9d are attached, and the support roll 3 pipes are suspended. And a branch pipe 21 installed to do so.
Of the configuration of the spray nozzle moving device 11, the configuration other than the header tube is an aspect of the header tube moving device in the present invention.

Each rotating shaft 31 has male screw portions (first male screw portion 37a, second male screw portion 37b, third male screw portion 37c and fourth male screw portion in order from the base end side of the rotating shaft 31) at four positions at predetermined intervals. The male screw portion 37d) is provided, and the first sleeve member 33a to the fourth sleeve member 33d are installed in the first male screw portion 37a to the fourth male screw portion 37d.
The first header member 35a to the fourth header tube 35d are fixed to the first sleeve member 33a to the fourth sleeve member 33d, respectively. The intervals between the first header tube 35a to the fourth header tube 35d are equal. Is set to
Since the intervals between the first header pipe 35a to the fourth header pipe 35d are equal intervals, the intervals between the branch pipes 21 installed in the first header pipe 35a to the fourth header pipe 35d are also equal intervals. The intervals (spray nozzle intervals) between the first spray nozzle 9a to the fourth spray nozzle 9d attached to the nozzle are also equal.
Further, the first header pipe 35a to the fourth header pipe 35d are arranged so that the intermediate position of the distance between the second header pipe 35b and the third header pipe 35c coincides with the intermediate position C in the slab width direction. If the horizontal distance from the intermediate position C in the slab width direction to the second header pipe 35b and the third header pipe 35c is m, the first header pipe 35a or the fourth header pipe 35d from the intermediate position C in the slab width direction. The horizontal distance is 3 m, which is three times the horizontal distance.
The interval between adjacent header tubes is 2 m.

  The first male screw portion 37a and the second male screw portion 37b are screws whose screw winding direction is clockwise (hereinafter referred to as “forward screw”), and the third male screw portion 37c and the fourth male screw portion 37d are The screw is wound counterclockwise (hereinafter referred to as “reverse screw”). Therefore, when the rotation shaft 31 is rotated, the first sleeve member 33a and the second sleeve member 33b move in the same direction with respect to the rotation shaft 31, and the third sleeve member 33c and the fourth sleeve member 33d rotate. The shaft 31 moves in the opposite direction to the first sleeve member 33a and the second sleeve member 33b. At this time, the first header pipe 35a and the second header pipe 35b move in the same direction with respect to the slab width direction, and the third header pipe 35c and the fourth header pipe 35d have the first header with respect to the slab width direction. The pipe 35a and the second header pipe 35b move in the opposite direction.

The first male screw portion 37a and the fourth male screw portion 37d have the same screw pitch, and the second male screw portion 37b and the third male screw portion 37c have the same screw pitch. The screw pitch of the first male screw portion 37a and the fourth male screw portion 37d is the same, and is set to three times the screw pitch of the second male screw portion 37b and the third male screw portion 37c.
Therefore, when the rotary shaft 31 is rotated, the first sleeve member 33a and the fourth sleeve member 33d move in the opposite directions by the same distance with respect to the rotary shaft 31, and the second sleeve member 33b and the third sleeve member 33c moves in the opposite direction to each other by the same distance relative to the rotating shaft 31 (a distance that is 1/3 of the moving distance of the first sleeve member 33a and the fourth sleeve member 33d). At this time, the first header pipe 35a and the fourth header pipe 35d move in the opposite directions by the same distance with respect to the slab width direction, and the second header pipe 35b and the third header pipe 35c move in the slab width direction. Are moved in opposite directions by the same distance (1/3 of the moving distance of the first header pipe 35a and the fourth header pipe 35d). That is, the ratio of the moving distance of each header pipe is proportional to the ratio of the distance from the center of the slab width direction, and is disposed on a different side from the header pipe disposed on the same side with respect to the center of the slab width direction. The header tube moves in the opposite direction.

As described above, since the first spray nozzle 9a to the fourth spray nozzle 9d are attached to the first header pipe 35a to the fourth header pipe 35d via the branch pipes 21, respectively, the first spray nozzle 9a to the fourth header pipe 35d are attached. The 4 spray nozzle 9d moves in the same manner as the first header pipe 35a to the fourth header pipe 35d.
That is, when the rotating shaft 31 is rotated, the first spray nozzle 9a and the fourth spray nozzle 9d move in opposite directions by the same distance with respect to the rotating shaft 31, and the second spray nozzle 9b and the third spray nozzle 9 9c moves in the opposite direction to each other by the same distance (a distance of 1/3 of the moving distance of the first sleeve member 33a and the fourth sleeve member 33d) with respect to the rotation shaft 31.

The spray nozzle interval when the rotating shaft 31 rotates will be specifically described.
The spray nozzle interval before the rotation of the rotating shaft 31 is an equal interval, and this is assumed to be 2 m. The rotation shaft 31 rotates in the direction of increasing the spray nozzle interval, and the second spray nozzle 9b and the third spray nozzle 9c move by a distance L in a direction away from each other, and the second spray nozzle 9b and the third spray nozzle 9c Assume that the spray nozzle interval is 2 m + 2 L. At this time, the first spray nozzle 9a moves by 3L in the same direction as the second spray nozzle 9b. Therefore, the spray nozzle interval between the first spray nozzle 9a and the second spray nozzle 9b is obtained by adding the distance 3L of the movement of the first spray nozzle 9a to the original spray nozzle interval of 2 m, and the second spray nozzle 9b is the first spray nozzle. The distance L moved to the 9a side is subtracted to be 2m + 2L. Similarly, the spray nozzle interval between the third spray nozzle 9c and the fourth spray nozzle 9d is also 2m + 2L. That is, the intervals between all the spray nozzles are 2m + 2L, and are maintained at equal intervals even after the rotation shaft 31 is rotated.

In addition, when the spray nozzle interval is changed, it is preferable to change the cooling range of the first spray nozzle 9a to the fourth spray nozzle 9d accordingly.
For example, when the slab width is changed from a narrow case to a wide case, the spray nozzle interval is widened, so that the cooling range of the first spray nozzle 9a to the fourth spray nozzle 9d is increased, for example, the first spray nozzle. What is necessary is just to make wide the angle (henceforth a "spray angle") which the spray ejected from 9a-the 4th spray nozzle 9d makes. Specifically, the amount of refrigerant is increased and / or the amount of supplied air is increased.
Conversely, when the spray nozzle interval is narrowed, for example, the spray angle may be narrowed so as to narrow the cooling range of the first spray nozzle 9a to the fourth spray nozzle 9d. Specifically, the amount of refrigerant is reduced and / or the amount of supplied air is reduced.

Next, the operation of the secondary cooling device 1 of the present embodiment configured as described above will be described.
When cooling a slab wider than the slab 5 shown in FIG. 1, as shown in FIG. 4, the rotary shaft 31 is rotated clockwise as viewed from the base end side, and the The spray nozzle interval is widened so that the outside of the spray range of the 1 spray nozzle 9 a and the 4th spray nozzle 9 d becomes the edge portion of the cast piece 39. At this time, the spray nozzles 9a to 9d move in the horizontal direction while maintaining the initial ratio, that is, 1: 1. Then, the refrigerant flow rate and / or the air flow rate are set so as to widen the cooling range of the first spray nozzle 9a to the fourth spray nozzle 9d so that no gap is generated in the cooling range of the first spray nozzle 9a to the fourth spray nozzle 9d. adjust.

  Moreover, when cooling the slab narrower than the slab 5 shown in FIG. 1, as shown in FIG. 5, the rotating shaft 31 is rotated counterclockwise when viewed from the base end side, and the slab width direction is changed. The spray nozzle interval is narrowed so that the outside of the spray range of the first spray nozzle 9a and the fourth spray nozzle 9d at both ends becomes the edge portion of the cast piece 41. At this time, the spray nozzles 9a to 9d move in the horizontal direction while maintaining the initial ratio, that is, 1: 1. Then, the refrigerant flow rate and / or the air flow rate are set so as to narrow the cooling range of the first spray nozzle 9a to the fourth spray nozzle 9d so that the cooling range of the first spray nozzle 9a to the fourth spray nozzle 9d does not largely overlap. Adjust.

  As described above, in the secondary cooling device 1 of the present embodiment, when the spray nozzle interval is adjusted in accordance with the slab width, each spray nozzle only moves in the horizontal direction. Since the spraying position of the spray does not move above the support roll 3 and the spray is not blocked by the support roll 3, the spray efficiency is not lowered. Moreover, since the 1st spray nozzle 9a-the 4th spray nozzle 9d move maintaining the spray nozzle space | interval in the initial ratio, a cooling nonuniformity does not arise.

The adjustment of the spray nozzle interval in the secondary cooling device 1 is automatically performed. An outline of a control device for performing automatic control in that case will be described below.
FIG. 6 is a block diagram for explaining the outline of the control device 51.
The control device 51 includes a spray position control unit 53 that controls the spray nozzle interval by controlling the motor 23 with a reduction gear, and an air flow rate adjustment valve that adjusts the air flow rate supplied to the first spray nozzle 9a to the fourth spray nozzle 9d. An air flow rate control unit 57 that controls the opening degree of 55, a refrigerant flow rate control unit 61 that controls the opening degree of the refrigerant flow rate adjustment valve 59 that adjusts the refrigerant flow rate supplied to the first spray nozzle 9a to the fourth spray nozzle 9d, and It has.
The control device 51 receives information such as casting speed, slab width, outlet side slab temperature, slab edge temperature, slab width direction temperature unevenness, spray pitch unevenness and the like as information for performing each control. Each information is acquired by various sensors.

  FIG. 7 is a diagram showing a control flow. The control flow will be described based on FIG. When the slab width is input, the spray position control unit 53 calculates the movement distance of the first spray nozzle 9a to the fourth spray nozzle 9d based on the slab width, and the spray nozzle moving device 11 based on the calculation result. To control. When the temperature unevenness in the width direction of the slab is caused by unevenness in the cooling range of the first spray nozzle 9a to the fourth spray nozzle 9d (spray pitch unevenness), the air flow rate is adjusted by the air flow rate adjustment unit, and the slab Reduce temperature unevenness in the width direction. When the temperature of the slab edge is lowered, the information on the slab width is corrected and the positions of the first spray nozzle 9a to the fourth spray nozzle 9d are readjusted. Thereby, an appropriate temperature distribution is ensured.

  On the other hand, as control for ensuring an appropriate slab temperature, a casting speed is input, and based on this, the refrigerant flow rate control unit 61 calculates an appropriate cooling speed. The refrigerant flow rate control unit 61 controls the refrigerant flow rate by adjusting the opening of the refrigerant flow rate adjustment valve 59 based on the calculation result, the spray width information, and the fed-out slab temperature fed back. The temperature on the outlet side of the secondary cooling device 1 in the slab is fed back to the refrigerant flow rate control unit 61 as described above. Thereby, an appropriate slab temperature is ensured.

In the first embodiment, the case where the number of header tubes is four has been described. However, the number of header tubes is not particularly limited.
However, when the number of header pipes is an odd number, one header pipe is arranged at the center of the slab width direction, the header pipe is fixed, and the header pipes arranged on both sides of the fixed header pipe are moved. What should I do?
When the number of header pipes increases, the gap between adjacent header pipes becomes narrow, and there may be a case where a sleeve member for supporting and moving all the header pipes cannot be installed on one rotary shaft 31. Arise. In such a case, the number of rotating shafts 31 that support the header tube in a movable manner may be increased and assigned.

FIG. 8 is an explanatory view for explaining an aspect of the secondary cooling device 71 in the case as described above.
In the example shown in FIG. 8, a fifth header pipe 35e, a sixth header pipe 35f, and a seventh header pipe 35g are added to the secondary cooling device 1 shown in FIG. 2, and the number of header pipes is seven. , Is an odd number. In FIG. 8, the same parts as those in FIG. 2 and corresponding parts are denoted by the same reference numerals.
Since the number of header pipes is an odd number, the sixth header pipe 35f disposed at the center of the slab width direction is fixed and does not move.
Moreover, in the example shown in FIG. 8, since the number of header pipes is increasing, two rotating shafts 31 are added. The added rotary shaft 31 supports the fifth header pipe 35e and the seventh header pipe 35g.

<Embodiment 2>
In the first embodiment, as the mechanism of the spray nozzle moving device 11, the first sleeve member 33a to the fourth sleeve member 33d are movably installed on the rotating shaft 31, and the first header pipe 35a is provided on each of the sleeve members. The fourth header pipe 35d is fixed.
However, the spray nozzle moving device may be any mechanism as long as it moves the first sleeve member 33a to the fourth sleeve member 33d in the slab width direction while maintaining the ratio of the spray nozzle interval.
The second embodiment shows another example of the mechanism of the spray nozzle moving device.
FIG. 9 is an explanatory diagram of the secondary cooling device 101 of the present embodiment, in which the same parts as those in FIGS. 1 and 2 showing the first embodiment are denoted by the same reference numerals.

The secondary cooling device 101 according to the present embodiment employs a chain transmission mechanism using a roller chain and a sprocket as the mechanism of the spray nozzle moving device 103.
Hereinafter, the secondary cooling device 101 of the present embodiment will be described based on FIG. 9 with the spray nozzle moving device 103 as the center.
As shown in FIG. 9, the spray nozzle moving device 103 according to the present embodiment includes a first transmission unit 105 disposed on the upper side in the drawing and a second transmission unit 107 disposed on the lower side in the drawing.
The first transmission unit 105 includes a single-stage sprocket 109 disposed on one side of the slab width direction, a first two-stage sprocket 111a and a second two-stage sprocket disposed on the single-stage sprocket 109 and the slab width direction. 111b and a third two-stage sprocket 111c. The first to third two-stage sprockets 111c are two-stage sprockets in which a small diameter portion is formed on a large diameter portion.

The large diameter portions of the single stage sprocket 109 and the first second stage sprocket 111a to the third second stage sprocket 111c are set to have the same diameter and the same number of teeth. The small diameter portions of the first two-stage sprocket 111a to the third two-stage sprocket 111c are set to have the same diameter and the same number of teeth.
The circumference ratio of the large diameter portion and the small diameter portion of the single-stage sprocket 109 and the first two-stage sprocket 111a to the third two-stage sprocket 111c is set to 3: 1.
The first roller chain 113a is wound around the large-diameter portion of the single-stage sprocket 109 and the first two-stage sprocket 111a, and the small-diameter portion of the first two-stage sprocket 111a and the small-diameter portion of the second two-stage sprocket 111b are second. The roller chain 113b is wound, and the third roller chain 113c is wound around the large diameter portion of the second second-stage sprocket 111b and the large diameter portion of the third second-stage sprocket 111c.

The second transmission unit 107 has the same configuration as the first transmission unit 105, and in FIG. 9, the part corresponding to the part configuring the first transmission unit 105 in the part configuring the second transmission unit 107 is the same. The symbol is attached.
An interlocking roller chain 115 is wound around the small diameter portion of the third two-stage sprocket 111c of the first transmission portion 105 and the small diameter portion of the third two-stage sprocket 111c of the second transmission portion 107, whereby the first transmission The part 105 and the second transmission part 107 can be interlocked.

The arrangement of the first header pipe 35a to the fourth header pipe 35d is the same as in the first embodiment, and is arranged so that the intervals between adjacent header pipes are equal.
The fourth header pipe 35d is fixed to the upper side of the first roller chain 113a in the figure via a fourth connecting part 117d. The third header pipe 35c is attached to the upper side of the second roller chain 113b in the drawing via a third connecting portion 117c. Further, the second header pipe 35b is fixed to the lower side of the second roller chain 113b in the drawing via a second connecting portion 117b. Further, the first header pipe 35a is fixed to the lower side of the third roller chain 113c in the figure via the first connecting portion 117a.

In the spray nozzle moving device 103 of the present embodiment configured as described above, when the single-stage sprocket 109 of the first transmission unit 105 is rotationally driven by a driving device (not shown), the first transmission unit 105 and the second transmission unit All 107 sprockets (single-stage sprocket 109, first two-stage sprocket 111a to third two-stage sprocket 111c) rotate in the same direction and at the same rotation speed.
By rotating all the sprockets, all the roller chains wound around this (the first roller chain 113a to the third roller chain 113c, the interlocking roller chain 115) rotate, and the first roller chain 113a to the third roller chain rotate. The first header pipe 35a to the fourth header pipe 35d attached to the roller chain 113c via the first connecting portion 117a to the fourth connecting portion 117d move in the slab width direction.
Hereinafter, the moving direction and moving distance of the first header pipe 35a to the fourth header pipe 35d will be described.

When the single-stage sprocket 109 of the first transmission unit 105 is rotated in the direction of the arrow (clockwise) in the figure by a driving device (not shown), the fourth header pipe 35d and the third header pipe 35c are indicated by the arrows in the figure. The second header pipe 35b and the first header pipe 35a move in the left direction in the figure. Further, the moving distance between the fourth header pipe 35d and the first header pipe 35a is equal, and the moving distance between the third header pipe 35c and the second header pipe 35b is equal. Furthermore, the moving distance of the fourth header pipe 35d and the first header pipe 35a is three times the moving distance of the third header pipe 35c and the second header pipe 35b.
This will be specifically described below. Assume that the initial interval between the header pipes is equal to m, and that the third header pipe 35c and the second header pipe 35b have moved by L in the direction of the arrow in FIG. At this time, the distance between the third header pipe 35c and the second header pipe 35b is m-2L.
Further, the distance between the fourth header pipe 35d and the third header pipe 35c is such that the fourth header pipe 35d moves 3L in the right direction in the figure and the third header pipe 35c moves by L in the right direction in the figure. −3L + L = m−2L. Further, the distance between the second header pipe 35b and the first header pipe 35a is such that the first header pipe 35a moves 3L in the left direction in the figure and the first header pipe 35a moves in the left direction in the figure by L. −3L + L = m−2L.
As described above, also in the case of the spray nozzle moving device 103 of the present embodiment, the first header pipe 35a to the fourth header pipe 35d may be moved in the slab width direction as in the case of the first embodiment. These intervals are kept at the original ratio (1: 1).

  Therefore, also in the secondary cooling device 101 of the present embodiment, the spray efficiency does not decrease as in the case of the first embodiment, and the first spray nozzle 9a to the fourth spray nozzle 9d are sprayed. Since the nozzle spacing is moved while maintaining the original ratio, there is an effect that cooling unevenness does not occur.

In the second embodiment, the case where the single-stage sprocket 109 of the first transmission unit 105 is rotationally driven by a driving device (not shown) has been described, but any sprocket that is rotationally driven may be used.
Further, it goes without saying that the change in the number of header tubes and the case where the number of header tubes is an odd number can be dealt with by adding the same change as described in the first embodiment.

  Of the configuration of the spray nozzle moving device 103 in the present embodiment, the configuration other than the header tube is an aspect of the header tube moving device of the present invention.

  The spray nozzle moving device 103 of the present invention is not limited to the first and second embodiments, and can be applied by applying various mechanisms. For example, a mechanism using a rack and pinion with a different gear ratio, or an electromagnetically controllable mechanism such as a hydraulic cylinder or an electric cylinder may be applied.

<Embodiment 3>
The secondary cooling device 131 according to the present embodiment will be described.
In the spray nozzle moving device 11 of the first embodiment, the header pipe is directly attached to the sleeve member. However, in the spray moving device 133 of the present embodiment, a connecting rod is installed between the sleeve member and the header pipe. Thus, a configuration is adopted in which the header pipe is supported by the connecting rod.
Moreover, the point which attaches four sleeve members to one rotating shaft is the same as that of Embodiment 1, but the position and screw pitch differ from Embodiment 1.

Hereinafter, points different from the first embodiment will be described in detail with reference to FIGS. 10 shows a case where the slab 5 to be cooled is cooled, and FIG. 11 shows a case where the slab 39 wider than the slab 5 is cooled.
Note that the secondary cooling device 131 according to the present embodiment differs from the first embodiment only in the configuration of the spray moving device, and the other configurations are the same. Therefore, in FIGS. 10 and 11, FIGS. The same parts as those in FIG. 2 are denoted by the same reference numerals, and description thereof is omitted.
Also in the present embodiment, the configuration of the spray nozzle moving device 133 other than the header tube is one aspect of the header tube moving device of the present invention.

First, a support structure for the first header pipe 35a to the fourth header pipe 35d will be described.
The first header pipe 35a includes a first connecting rod 137a having one end pin-coupled to the first sleeve member 135a and the other end pin-coupled to the first header pipe 35a, and one end pin-coupled to the second sleeve member 135b. The end is supported by a second connecting rod 137b pin-coupled to the first header pipe 35a.
The second header pipe 35b includes a third connecting rod 137c whose one end is pin-coupled to the second sleeve member 135b and the other end is pin-coupled to the second header pipe, and one end is pin-coupled to a fixing portion 139 such as an apron. The end is supported by a fourth connecting rod 137d that is pin-coupled to the second header pipe 35b. In addition, the fixing | fixed part 139 is located above the intermediate position C of the slab width direction.
The third header pipe 35c has one end pin-coupled to the fixing portion 139 and the other end pin-coupled to the third header pipe 35c, and one end pin-coupled to the third sleeve member 135c and the other end pin-coupled. It is supported by a sixth connecting rod 137f that is pin-coupled to the third header tube 35c.
The fourth header pipe 35d includes a seventh connecting rod 137g having one end pin-coupled to the third sleeve member 135c and the other end pin-coupled to the fourth header pipe 35d, and one end pin-coupled to the fourth sleeve member 135d. The end is supported by an eighth connecting rod 137h pin-coupled to the fourth header pipe 35d.

The first connecting rod 137a to the eighth connecting rod 137h have the same length, and the pin coupling positions on the sleeve member side or the fixing portion 139 side of the first connecting rod 137a to the eighth connecting rod 137h are equally spaced. It has become.
Since the first connecting rod 137a to the eighth connecting rod 137h support each header tube as a set of two as described above, each header tube is connected to the sleeve member side or the fixed portion of the connecting rod that supports the header tube. It is arranged in the center in plan view of the pin coupling position on the 139 side.
Therefore, a straight line connecting the pin coupling positions of the adjacent sleeve members or the fixing portion 139 and the sleeve member adjacent thereto is the bottom, and the triangle having the apex at the pin coupling position on the header pipe side facing the bottom is adjacent to the triangle. The triangles having the pin connection position on the header pipe side as the base and the pin connection position of the sleeve member or the fixing portion 139 facing this as the apex are congruent. Therefore, the interval between the pin coupling positions of the adjacent sleeve members or the fixing portion 139 and the sleeve member adjacent thereto and the interval between the pin coupling positions on the header pipe side are the same. As described above, since the intervals between the pin coupling positions of the adjacent sleeve members or the fixing portion 139 and the sleeve member adjacent thereto are equal intervals, the pin coupling positions on the header pipe side are also equal intervals.

  Since the pin coupling positions of the first connecting rod 137a to the eighth connecting rod 137h on the sleeve member side or the fixing portion 139 side are equally spaced, it is assumed that the pin coupling position from the fixing portion 139 to the pin coupling position of the second sleeve member 135b is assumed. When the distance is n, the distance from the fixing portion 139 to the pin coupling position of the third sleeve member 135c is also n. Further, the distance from the fixing portion 139 to the pin coupling position of the first sleeve member 135a and the distance from the fixing portion 139 to the pin coupling position of the fourth sleeve member 135d are both 2n.

  The first male screw portion 141a and the second male screw portion 141b are forward screws, and the third male screw portion 141c and the fourth male screw portion 141d are reverse screws. Therefore, when the rotation shaft 143 is rotated, the first sleeve member 135a and the second sleeve member 135b move in the same direction with respect to the rotation shaft 143, and the third sleeve member 135c and the fourth sleeve member 135d rotate. The shaft 143 moves in the opposite direction to the first sleeve member 135a and the second sleeve member 135b. This is the same as in the first embodiment.

The first male screw portion 141a and the fourth male screw portion 141d have the same screw pitch, and the second male screw portion 141b and the third male screw portion 141c have the same screw pitch. The screw pitch of the first male screw portion 141a and the fourth male screw portion 141d is set to be twice the screw pitch of the second male screw portion 141b and the third male screw portion 141c.
Accordingly, when the rotation shaft 143 is rotated, the second sleeve member 135b and the third sleeve member 135c move in the opposite directions by the same distance with respect to the rotation shaft 143, and the first sleeve member 135a and the fourth sleeve member 135d moves in the opposite directions to each other by the same distance (a distance twice as long as the second sleeve member 135b and the third sleeve member 135c) with respect to the rotation shaft 143.

For example, when the rotation shaft 143 rotates in the direction of widening the spray nozzle interval and the second sleeve member 135b and the third sleeve member 135c move by L in a direction away from each other, the first sleeve member 135a and the fourth sleeve member 135d are , Move 2L away from each other. At this time, the interval between the pin coupling positions of the fixing portion 139 and the second sleeve member 135b and the interval between the pin coupling positions of the fixing portion 139 and the third sleeve member 135c are n + L. In addition, the interval between the pin coupling position of the second sleeve member 135b and the pin coupling position of the first sleeve member 135a is shortened by L from which the second sleeve member 135b moves to the first sleeve member 135a side from the initial n. Since the first sleeve member 135a moves by 2L in the direction away from the second sleeve member 135b, n−L + 2L = n + L. Similarly, the pin coupling position of the third sleeve member 135c and the pin coupling position of the fourth sleeve member 135d are n + L. Therefore, the intervals between the pin coupling positions of the adjacent sleeve members or the fixing portion 139 and the adjacent sleeve member are maintained at equal intervals.
As described above, since the interval between the pin coupling positions of the adjacent sleeve members or the fixing portion 139 and the sleeve member adjacent thereto and the interval between the pin coupling positions on the header pipe side are the same, the rotation shaft Even if 143 rotates, the interval between the pin coupling positions on the header tube side is kept the same. Since the interval between the pin coupling positions on the header tube side is the same as the spray nozzle interval, the spray nozzle interval is also kept the same.

As described above, also in the spray nozzle moving device 133 of the third embodiment, by rotating the rotating shaft 143, each spray nozzle is moved in the slab width direction while maintaining the ratio of the distance between the spray nozzles. Can be made.
In addition, it is the same as that of Embodiment 1, 2 that the moving distance of each header pipe | tube and each spray nozzle in case the rotating shaft 143 rotates is proportional to the ratio of the distance from the center position C of a slab width direction. .

When each spray nozzle is moved so as to spread in the slab width direction, each spray nozzle is pulled up by the connecting rod, so that the height of the spray nozzle from the slab increases. Since the spray range is widened by increasing the height of the spray nozzle, it is possible to prevent the spray gap from being generated due to the wide distance between the spray nozzles, or to reduce the gap.
On the contrary, when each spray nozzle is moved so as to narrow in the slab width direction, each spray nozzle is pushed down by the connecting rod, so that the height of the spray nozzle from the slab becomes low. Since the spray range is narrowed by reducing the height of the spray nozzles, it is possible to prevent or reduce the overlap of sprays caused by the narrowing of the distance between the spray nozzles.

Here, the relationship between the height of the spray nozzle from the slab and the spray range when the distance between the spray nozzles changes will be described in more detail with reference to FIG.
FIGS. 12A to 12C show a part of the state in which the refrigerant is injected from the two adjacent spray nozzles onto the surface 145 of the slab 5. Since the relationship between two adjacent spray nozzles is the same between the spray nozzles, in the following description, the second spray nozzle 9b and the third spray nozzle 9c will be described.

FIG. 12A shows a part extracted from the range surrounded by the dotted frame W in FIG. 10 and omits the branch pipe and the header pipe.
Specifically, the fourth connecting rod 137d, the fifth connecting rod 137e, the second spray nozzle 9b, and the third spray nozzle 9c are shown, and the state of spraying from the respective spray nozzles to the surface 145 of the slab 5 is shown. ing.
The illustration of the first header pipe 35a to the fourth header pipe 35d and the branch pipe 21 is omitted in order to simplify the explanation.

  FIG. 12B shows a state in which the rotation shaft 143 is rotated forward from the state of FIG. 12A to increase the distance between spray nozzles, and FIG. 12C shows the state of FIG. Further, the rotation shaft 143 is further rotated forward to increase the distance between the spray nozzles.

Further, FIG. 12 (a) ~ (c), from the second spray nozzle 9b and the third spray nozzle 9c, the manner in which coolant is ejected as a spray angle theta _S on the surface 145 of the slab 5 of the spray nozzle center It is represented by a cross section passing through. Each of the two isosceles triangles (the isosceles triangle surrounded by the dotted line in FIG. 12 and the surface 145 of the slab 5) having the second spray nozzle 9b and the third spray nozzle 9c as vertices was sprayed. Refrigerant (hereinafter referred to as “spray refrigerant”). In addition, the shape of the spray refrigerant is originally a three-dimensional shape such as a cone, but the cross section is such that the cross section of the spray refrigerant is maximized. That is, the base of the isosceles triangle represents the maximum width of the spray range (hereinafter simply referred to as “spray range R”). The distance from the base of the isosceles triangle to the apex angle represents the spray height H from the slab 5.
Note that the length of the connecting rod is X.

FIG. 12A shows a state where there is no gap or overlap between the two spray refrigerants, and this state is an ideal state for injecting the refrigerant. Note that a point in contact of an isosceles triangle representing the two spray coolant and the point P _a.

FIG. 12B shows a state in which the rotating shaft 143 is rotated forward from the state of FIG. 12A and the distance between the spray nozzles is slightly widened as described above. As it spreads, the spray height H increases.
When the spray height H is increased, as shown in FIG. 12B, the isosceles triangle representing the spray refrigerant becomes larger, and the spray range R becomes wider. Further, since the isosceles triangle representing the spray refrigerant is similar before and after the change of the spray height H, the spray height H and the spray range R are in a proportional relationship before and after the change of the distance between the spray nozzles. Therefore, if the splay height H is increased in proportion to the spread of the splay range, that is, in proportion to the horizontal movement distance of the splay nozzle, no gap or overlap occurs in the splay range.
However, when the distance between the spray nozzles increases, the second spray nozzle 9b and the third spray nozzle 9c move on an arc whose radius is the length X of the fourth connecting rod 137d and the fifth connecting rod 137e. The increase in the distance between the spray nozzles cannot be proportional to the amount of change in the spray height H.
Therefore, gaps and overlaps occur in the spray range R before and after the change in the interval between the spray nozzles.

This will be described with reference to FIGS. 12B and 12C. In FIG. 12B, the spray range R is widened by increasing the spray height H, but the spread of the spray range R has not caught up with the increase in the distance between the spray nozzles. There is a gap in the spray range _{Rb of the} refrigerant ejected from (see the circled portion in FIG. 12B. Note that the circled portion in FIG. 12B is enlarged. (Shown below FIG. 12 (b)). Such a gap where the spray ranges R do not overlap is referred to as a spray gap S in the following description.

FIG. 12C shows a state in which the rotation shaft 143 is further rotated forward from the state of FIG. 12B to increase the distance between the spray nozzles. In FIG. 12 (c), the spray height H _c becomes too wide spray range R _c in be higher, and it is a portion overlapping with the spray range R _c adjacent. The part which overlaps in such splay range R is called spray overlap D in the following description.

  If the splay gap S and the splay overlap D (hereinafter collectively referred to as “spray error U”) occur as described above, it is considered that the slab 5 may be adversely affected. Therefore, since this effect was considered, this will be described below.

  As described above, it is ideal that there is no spray error U as shown in FIG. The ideal spray range R is a range in which one spray nozzle is to be cooled, and a spray error U occurs regardless of whether it is larger or smaller. The splay error U means how much the splay range is deviated from the ideal state. If the ratio of the splay error U to the ideal splay range R is obtained, the degree of the error and thus the slab cooling is given. I understand the impact.

Therefore, in the following, the splay error U will be considered when a gap is generated in the splay range shown in FIG. 12B and when the splay range shown in FIG.
First, in the case shown in FIG. 12B, the ratio of the spray error U (the spray gap S in the case of FIG. 12B) to the ideal spray range R is obtained. In FIG. 12, since the figure is too small, FIGS. 12 (a) and (b) are extracted and enlarged and shown in FIGS. 13 (a) and 13 (b).
In FIG. 13B, the two dotted lines extending below the solid line representing the surface 145 of the slab 5 represent the virtual spread of each spray refrigerant when the slab 5 is absent. The isosceles triangle formed by this virtual spread represents two virtual spray refrigerants. The point where the isosceles triangle representing these two virtual spray coolant contact and the point P _b. Since this virtual spray is an ideal spray state with no spray error U, this virtual spray refrigerant is an ideal spray refrigerant.

Here, the spray range of the ideal spray refrigerant is R _b ′, and the spray height is H _b ′. Also, the point P _b vertices and bottom spray gap S, the height of the isosceles triangle which is upside down and [Delta] L _b. Since this isosceles triangle and the isosceles triangle representing the ideal spray refrigerant have a similar relationship, the ratio of the spray gap S to be obtained to the ideal spray range R _b ′ is the height ΔL _b is high. It is the same as the ratio to H _b ′.
Therefore, by obtaining the ratio of the height ΔL _b to the height H _b ′, the ratio of the spray gap S to be obtained to the ideal spray range R _b ′ can be obtained.
Hereinafter, how to determine the ratio of the height ΔL _b to the height H _b ′ will be described.

In FIG. 13 (a), the length of the straight line connecting the fixing portion 139 and the _{P a} (fixed portion from 139 to the surface 145 of the slab 5 height and the same) and _{L a,} in FIG. 13 (b), the fixed part When the straight line connecting the 139 and _{P b} the length and _{L b,} height ΔLb is represented by the formula (1).
ΔL _b = L _b -L _a (1)

First, the _{L a.}
When _a perpendicular line is drawn from one spray nozzle to the straight line connecting the fixing portion 139 and Pa, a right triangle with the fourth connecting rod 137d as the hypotenuse is formed. Of the two straight lines at right angles to the right-angled triangle, and the length of the other straight line the perpendicular line and K _a, L _a is be represented by the length of the sum of the spray height H _a and K _a Can do.
H _a is the half length of the R _a and r _a, when the base angle of the spray coolant and theta, represented by the formula (2).
H _a = r _a tanθ (2)
On the other hand, K _a is obtained by the equation (3) from the three-square theorem.
K _a = (X ² −r _a ² ) ^1/2 (3)
From the above, _{L a} is the formula (4) is represented by the formula.
L _a = H _a + K _a = r _a tanθ + (X ² −r _a ² ) ^1/2 (4)

Next, _Lb will be examined. In FIG. _13B , when a perpendicular line is drawn from one spray nozzle to a straight line connecting the fixing portion 139 and Pb, a right triangle having the fourth connecting rod 137d as a hypotenuse is formed. Of the two straight lines forming a right angle of the right triangle, the length of the other side of the perpendicular is _Kb .
Since L _b is a length obtained by adding the ideal spray height H _b ′ and K _b , the following equation (5) is obtained.
L _b = H _b ′ + K _b = r _b tan θ + (X ² −r _b ² ) ^1/2 (5)
Here, r _b is half the length of the ideal spray range R _b ′, and θ is the base angle of an isosceles triangle representing the ideal spray refrigerant in FIG.

From equations (1), (4), and (5), ΔL _b is expressed by equation (6).
ΔLb = L _b -L _a = (r _b -r _a ) tanθ + (X ² -r _b ² ) ^{1/ 2-} (X ² -r _a ² ) ^1/2 (6)

Since the ideal spray height H _b ′ is r _b tanθ, the ratio of the height ΔL _b to the ideal spray height H _b ′ is expressed by Equation (7).
ΔL _b / H _b ′ = {(r _b −r _a ) tan θ + (X ² −r _b ² ) ^1/2 − (X ² −r _a ² ) ^1/2 } / r _b tanθ (7) )

As described above, the ratio (equation (7)) of the height ΔL _{b to} the ideal spray height H _b ′ is the ratio of the spray gap S _{b to} be obtained to the ideal spray range R _b ′ (S _b / R _b ′), that is, since it is the same as the error rate, S _b / R _b ′ can be expressed by equation (8).
S _b / R _b ′ = {(r _b −r _a ) tan θ + (X ² −r _b ² ) ^1/2 − (X ² −r _a ² ) ^1/2 } / r _b tanθ (8) )

  Next, in the state where there is a splay overlap D as shown in FIG. 12C, the ratio of the splay overlap D to the ideal spray range R will be examined.

In FIG.12 (c), let _Pc be the point where the hypotenuses of the respective isosceles triangles representing the two spray refrigerants intersect. Further, when a straight line passing through _Pc and parallel to the surface 145 of the slab 5 is drawn, two isosceles triangles having a corner including _Pc as a base angle are formed. These isosceles triangles are ideal spray refrigerants. The spray range of this ideal spray refrigerant is R _c ′, and the spray height is H _c ′.
Also, the height of the isosceles triangle in which the point P _c vertices and bottom of the spray overlap D and [Delta] L _c. Since the isosceles triangle and the isosceles triangle representing the ideal spray refrigerant are in a similar relationship, the ratio of the spray overlap D to be obtained to the ideal spray range R _c ′ is an ideal ΔL _c. It is the same as the ratio to the spray height H _c ′. Therefore, by obtaining the ratio of ΔL _c to the ideal spray height H _c ′, the ratio of the splay overlap D to be obtained to the ideal spray range R _c ′ can be obtained.
Hereinafter, how to obtain the ratio of the height ΔL _c to the spray height H _c ′ will be described.

In FIG. 12C, if the length of the straight line connecting the fixed portion 139 and P _c is L _c , the height ΔL _c is expressed by equation (9).
ΔL _c = L _a -L _c (9)

First, _Lc is examined.
In FIG. 13C, when a perpendicular line is drawn from one spray nozzle to a straight line connecting the fixed portion 139 and _Pc , a right triangle having a hypotenuse as a straight line representing the fourth connecting rod 137d is formed. Of the two straight lines forming a right angle of the right triangle, the length of the other side of the perpendicular is K _c .
Since L _c is a length obtained by adding the ideal splay height H _c ′ and K _c , Equation (10) is obtained.
L _c = H _c ′ + K _c = r _c tan θ + (X ² −r _c ² ) ^1/2 (10)
Here, r _c is half the length of the ideal spray range R _c ′, and θ is the base angle of an isosceles triangle representing the ideal spray refrigerant.

L _a can be represented by the formula (4) below, as described above.
L _a = H _a + K _a = r _a tanθ + (X ² −r _a ² ) ^1/2 (4)
Therefore, ΔL _c is expressed by Expression (11) from Expressions (4), (9), and (10).
ΔL _c = L _a -L _c = (r _a -r _c ) tanθ + (X ² -r _a ² ) ^{1/ 2-} (X ² -r _c ² ) ^1/2 (11)

Since the ideal spray height H _c ′ is r _c tanθ, the ratio of the height ΔL _c to the ideal spray height H _c ′ is expressed by Expression (12).
ΔL _c / H _c ′ = {(r _a −r _c ) tan θ + (X ² −r _a ² ) ^1/2 − (X ² −r _c ² ) ^1/2 } / r _c tanθ (12) )

As described above, the ratio of the height ΔL _{c to} the ideal spray height H _c ′ is the same as the ratio (D _c / R _c ′) of the spray overlap D _{c to be obtained to} the ideal spray range R _c ′. Therefore, D _c / R _c ′ can be expressed by equation (13).
D _c / R _c ′ = {(r _a −r _c ) tan θ + (X ² −r _a ² ) ^1/2 − (X ² −r _c ² ) ^1/2 } / r _c tanθ (13) )

Expression (8) is an error ratio when the spray gap S occurs, and Expression (13) is an error ratio when the spray overlap D occurs.
To compare these two equations, unified spray clearance S and spray overlap D splay error U _k, ideal spray range R _k, the symbol replaces the length of half the r _k.

In the formula (8), the spray space S spray error _{U k,} replacing the ideal spray range _{R k,} the length of the half _{r k,} the equation (14).
U _k / R _k = {(r _k −r _a ) tan θ + (X ² −r _k ² ) ^1/2 − (X ² −r _a ² ) ^1/2 } / r _k tanθ (14)

Similarly, in equation (13), the spray overlap D splay error _{U k,} replaces the ideal spray range _{R k,} the length of the half _{r k,} the equation (15).
U _k / R _k = {(r _a −r _k ) tan θ + (X ² −r _a ² ) ^1/2 − (X ² −r _k ² ) ^1/2 } / r _k tanθ (15)

Comparing equation (14) and equation (15), it can be seen that these are reversed in positive and negative. This is because when the value of U _k / R _k (ratio of the spray error U _{k to} the ideal spray range R _k ) is a positive value, the spray gap is as shown in FIG. When S is generated and becomes a negative value, it indicates that the splay overlap D is generated as in the case shown in FIG.

In order to reduce the influence of the spray error U _k generated as described above on the cooling of the slab when the interval between the spray nozzles is changed corresponding to the change of the slab width, U _k / R _What is necessary is just to make the value of _k small.
As can be seen from the equations (14) and (15), the value of U _k / R _k is related to the base angle of the isosceles triangle representing the ideal spray refrigerant: θ and the length of the connecting rod: X. In addition, the change ratio of the slab width is considered to be about twice.
Therefore, by changing the value of θ and X, spray range for each value of θ and X R _k from 2 4, that is, when the length r _k of the half was changed 0.1 increments from 1 to 2 The U _k / R _k of was exemplarily examined.
The examination results are shown in Tables 1 to 3.

Table 1 shows the case where X = 2.6 and θ = 35 °, Table 2 shows the case where X = 3.0 and θ = 30 °, and Table 3 shows the case where X = 2.2 and θ = 45 °.
In Table 1, the maximum value of U _k / R _k is 7.2%, Table 2 is 6.9%, and Table 3 is 10.0%. Therefore, in Tables 1 to 3, it can be said that the case of Table 2 is the case where the error ratio (U _k / R _k ) is the smallest. This means that the error ratio (U _k / R _k ) can be reduced by appropriately setting the base angle: θ of the isosceles triangle representing the ideal spray refrigerant and the length of the connecting rod: X. It means you can do it.

Hereinafter, the case of Table 2 with the smallest error ratio will be considered.
When the top of the table 2 See section of the third stage, in the state of r _k is 1, since the spray error U _k has not occurred, the ratio ideal spray range R _k spray error U _k is 0 %. Between r _k is 1.1 to 1.9, has a positive value, it can be seen that the spray gap S is generated. The ratio _U k / _{R k} for the ideal spray range _{R k} spray error _{U k} is, _{r k} is the maximum value in the vicinity of 1.4, the value is 6.9%.
When r _k is 2, the ratio U _k / R _k of the spray error U _{k to} the ideal spray range has turned to a negative value, indicating that a splay overlap D has occurred. Also, it has a minimum value -1.3% when _{r k} is 2.

FIG. 14 is a graph of Table 2. In FIG. 14, the horizontal axis represents the length of r _k , and the vertical axis represents the ratio of the spray error U _{k to} the ideal spray range R _k .
Referring to FIG. 14, the curve representing the ratio of the spray error U _{k to} the ideal spray range R _k is biased upward. This means that the splay gap S is likely to occur, and the ratio of the splay error U _{k to} the ideal splay range R _k when the splay gap S occurs is also large.

In the case of Table 2, the maximum value of the ratio of the spray error U _k (spray gap S) to the ideal spray range R _k is 6.9%, and even this value has a sufficiently small effect on the slab cooling. It can be said.
However, even if the spray gap S is generated, even if the spray overlap D occurs, the ratio for those ideal spray range R _k is, it is more preferably a smaller value.
Therefore, a method for reducing the ratio of the spray error U _{k to} the ideal spray range R _k when the values of θ and X are fixed was studied. The examination results are shown below.

In order to reduce the ratio of the splay error U _{k to} the ideal splay range R _k , the curve shown in FIG. 14 may be adjusted so as to reduce the upward bias by lowering the curve shown in FIG. .

In FIG. 14, in order to eliminate the upward bias of the curve, an average value (2.8%) of the maximum value (6.9%) and the minimum value (−1.3%) of the curve may be used as a reference value. In order to use the average value as the reference value, the average value may be subtracted from the value of U _k / R _k shown in Table 1. The results are shown in Table 4.

A graph of Table 4 is shown in FIG. Table 4, looking at Figure 15, next to the maximum value of 4.1% the rate _U k / _{R k} for the ideal spray range _{R k} spray error _{U k} if _{r K} is 1.4, the spray when _{r K} is 2.0 The ratio U _k / R _{k of the} error U _{k to} the ideal spray range R _k is the minimum value −4.1%, and the ratio of the spray error U _{k to} the ideal spray range R _k is suppressed to about ± 4.1%. I can see that
Thus, by reducing the bias of the value of U _k / R _k when r _K changes, it is possible to reduce the value of U _k / R _k and prevent slab cooling unevenness.

Next, a method for changing the state of FIG. 14 to the state of FIG. 15 will be described.
Ratio _U k / _{R k} to Figure 15 when in the vicinity of _{r K} is 1.09 for the ideal spray range _{R k} spray error _{U k} is 0%. Therefore, the initial value of the distance between the spray nozzles may be adjusted so that the spray error U _k does not occur when r _K is near 1.09.

As described above, in the secondary cooling device 131 of the present embodiment, when three or more spray nozzles are arranged in the slab width direction and the spray nozzle interval is adjusted in accordance with the slab width, each spray nozzle Since the spray nozzles are moved in the horizontal direction and in the direction of separating from and coming into contact with the slab while maintaining the distance ratio, the moving distance of the spray nozzles approaching and leaving the slab can be reduced. Therefore, the spray position of the spray from each spray nozzle does not move above the support roll, the spray is not blocked by the support roll, and the spray efficiency does not decrease. In addition, each spray nozzle moves in a direction that keeps the distance between adjacent spray nozzles at the initial ratio and is in contact with the slab, so that cooling without uneven cooling is possible without changing the spray angle. Become.
However, when the distance between the spray nozzles is changed as in the first embodiment, it is not excluded that the spray angle is finely adjusted to further reduce the cooling unevenness.

Although the number of header tubes in the secondary cooling device 131 is four, the present invention can be applied by changing the number of sleeve members even when the number of header tubes increases or decreases.
Further, the number of header pipes of the secondary cooling device 131 is an even number, but the present invention is applicable even when the number of header pipes is an odd number. In this case, the fixing part 139 is unnecessary. Further, in this case, the central header pipe is installed so as to be positioned at the central position C in the slab width direction, and the header pipe does not move in the width direction of the slab 5 even if the rotary shaft 143 rotates.

  As an example, FIG. 16 shows a mode in which the number of header tubes is three. In the example of FIG. 16, the number of header pipes is three, and the number of sleeve members installed on one rotating shaft is four. The male screw portion (position, pitch) of the rotating shaft is the same as that of the rotating shaft 31 of the first embodiment, and each sleeve member installed corresponding to each male screw portion is also the same as that of the first embodiment. It is the same as each sleeve member. The first header pipe 35a is connected to the first sleeve member 33a and the second sleeve member 33b, the second header pipe 35b is connected to the second sleeve member 33b and the third sleeve member 33c, and the third header pipe 35c is connected to the third sleeve. The member 33c and the fourth sleeve member 33d are connected by connecting rods (first connecting rod 147a to sixth connecting rod 147f), respectively.

C center position W dotted frame 1 secondary cooling device 3 support roll 5 slab 7 continuous casting equipment 9a first spray nozzle 9b second spray nozzle 9c third spray nozzle 9d fourth spray nozzle 11 spray nozzle moving device 13 tundish 15 Mold 17 Molten steel 19 Segment 21 Branch pipe 23 Motor with reduction gear 25 T-shaped miter gear box 27 Connecting shaft 29 L-shaped miter gear box 31 Rotating shaft 33a First sleeve member 33b Second sleeve member 33c Third sleeve member 33d First 4th sleeve member 33e 5th sleeve member 33g 6th sleeve member 35a 1st header pipe 35b 2nd header pipe 35c 3rd header pipe 35d 4th header pipe 35e 5th header pipe 35f 6th header pipe 35g 7th header pipe 37a 7th header pipe 1 Male thread part 37 b 2nd male screw part 37c 3rd male screw part 37d 4th male screw part 37e 5th male screw part 37g 6th male screw part 39 Cast piece 41 Cast piece 51 Control device 53 Spray position control part 55 Air flow rate adjustment valve 57 Air flow control unit 59 Refrigerant flow control valve 61 Refrigerant flow control unit 71 Secondary cooling device 101 Secondary cooling device 103 Spray nozzle moving device 105 First transmission unit 107 Second transmission unit 109 Single stage sprocket 111a First two stage sprocket 111b Second second stage sprocket 111c Third second stage sprocket 113a First roller chain 113b Second roller chain 113c Third roller chain 115 Interlocking roller chain 117a First connecting part 117b Second connecting part 117c Third connecting part 117d Fourth connecting part 131 Secondary cooling device 133 Spray moving device 135a First spray Leave member 135b Second sleeve member 135c Third sleeve member 135d Fourth sleeve member 137a First connecting rod 137b Second connecting rod 137c Third connecting rod 137d Fourth connecting rod 137e Fifth connecting rod 137f Sixth connecting rod 137g Seventh Connecting rod 137h Eighth connecting rod 139 Fixed portion 141a First male screw portion 141b Second male screw portion 141c Third male screw portion 141d Fourth male screw portion 143 Rotating shaft 145 Surface 147a First connecting rod 147b Second connecting rod 147c Third connecting rod 147d Fourth connecting rod 147e Fifth connecting rod 147f Sixth connecting rod

Claims (7)

A secondary cooling device that performs secondary cooling of the slab in a continuous casting facility that supports the slab by sandwiching the upper and lower sides of the slab with a plurality of support rolls and continuously casts the slab from the mold,
Each of the sprays while maintaining the ratio of the distance between the spray nozzles arranged in the gap width direction between the plurality of support rolls arranged in the drawing direction of the slab and the adjacent spray nozzles. A secondary cooling device for continuous casting equipment, comprising a spray nozzle moving device for moving the nozzle in the slab width direction.   The secondary cooling device for a continuous casting facility according to claim 1, wherein the spray nozzle moving device moves the spray nozzle in parallel to the surface of the slab. The spray nozzle moving device is:
When moving the spray nozzle in a direction in which the ratio of the distance between the adjacent spray nozzles is increased, the spray nozzle is also moved in a direction in which the distance between the spray nozzle and the slab is separated,
When the spray nozzle is moved in a direction in which the ratio of the distance between adjacent spray nozzles is reduced, the spray nozzle is also moved in a direction in which the distance between the spray nozzle and the slab approaches. The secondary cooling device for continuous casting equipment according to claim 1. The spray nozzle moving device has three or more header pipes arranged at equal intervals in the slab width direction and supplied with a refrigerant, and maintains the ratio of the distance between the header pipes that support the header pipes and are adjacent to each other. A header pipe moving device for moving each header pipe in the slab width direction;
The secondary cooling device for a continuous casting facility according to any one of claims 1 to 3, wherein the spray nozzle is attached to the header pipe via a branch pipe.   The header pipe moving device supports the same number of header pipes arranged on both sides with the center of the slab width direction as a boundary, and the header pipe has a moving distance ratio from the center of the slab width direction. It is proportional to the ratio of the distance, and is moved so that the movement direction of the one arranged on the same side and the one arranged on a different side with respect to the center of the slab width direction is opposite. Item 5. A secondary cooling device for continuous casting equipment according to item 4.   The secondary cooling device for a continuous casting facility according to claim 4 or 5, wherein the header pipe moving device moves the header pipe in a direction parallel to a slab surface. The header pipe moving device supports the header pipe via a connecting rod,
When moving the header pipe in the direction in which the ratio of the distance between the adjacent header pipes is increased, the header pipe is also moved in a direction in which the distance between the header pipe and the cast piece is increased,
The header pipe is also moved in a direction in which the distance between the header pipe and the cast piece approaches when the header pipe is moved in a direction in which the ratio of the distance between the adjacent headers decreases. Item 6. The secondary cooling device for continuous casting equipment according to Item 4 or 5.