JP2004050121A - Nozzle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize an ejection pattern even when a flow rate is changed. <P>SOLUTION: The tip of an inflow hole 16 of a large diameter along the central axis of a body 15 is made to communicate with independent holes 17 and 18, and the holes 17 and 18 are formed at symmetric positions in relation to the central axis through a partition 19. The channel area of the ejection side of each independent hole 17 or 18 is decreased gradually, and the tip is closed. A notch part 22 cut in the diameter direction in the shape of an arc or a taper is formed in the ejection side end surface of the body 15. The side on the central axis side of each independent hole 17 or 18 is notched by the notch part 22, and L-shaped perpendicular jet holes 20 and 21 opened to the side 22b and bottom surface 22a of the notch part 22 are formed. A spray thickness is expanded by the collision between fluids ejected from each jet hole 20 or 21 formed to face both sides of the notch part 22. A spray width is restricted in the notch part 22 by guiding the fluid ejected from each jet hole 20 or 21 by the notch part 22. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a nozzle, and more particularly to a nozzle capable of uniformly cooling a high-temperature steel sheet by using it in a continuous caster of steel or the like.
[0002]
[Prior art]
2. Description of the Related Art In recent years, in a continuous casting machine for manufacturing a steel sheet, cost reduction and high quality have been required at the same time with intensified international competition. Conventionally, when cooling a high-temperature steel sheet with the continuous casting machine, it is usual to perform cooling by spraying mist with a two-fluid spray nozzle.
As such a nozzle, a nozzle 1 as shown in FIG. 14 is used.
The nozzle 1 forms an injection port by forming an orifice 3 at the tip of an independent hole 2 formed on the center axis and providing a cutout 4 communicating with the orifice 3 from the injection side.
[0003]
Alternatively, the nozzle 5 disclosed in Japanese Patent Publication No. 3-15493 shown in FIG. 15 has a nozzle tip 6 attached to a tip of an adapter 9 into which a liquid and a gas are mixed and flow.
The nozzle tip 6 is provided with a stirring chamber 7 having a circular cross section, and is provided with a nozzle opening 6a which is inclined in a direction away from the front opening of the stirring chamber 7 and has two inlet holes facing each other on the side wall of the stirring chamber 7. 8 are drilled.
[0004]
[Problems to be solved by the invention]
However, in spite of the fact that a wide cooling range from rapid cooling to slow cooling is required by changing the injection flow rate by one continuous casting machine, in the nozzle 1 shown in FIG. In addition, the jet angle θn in the spray thickness direction also fluctuates, which may cause cooling unevenness and lead to a deterioration in the quality of the steel sheet. In particular, when the flow rate of the gas to the liquid is lowered and only the liquid is jetted, FIG. As shown in the conventional example 1, there is a problem that the spray angle θn in the spray thickness direction T becomes small.
Also, in the nozzle 5 shown in FIG. 15, when the flow rate changes, the injection angle θw in the spray width direction also changes, which may cause uneven cooling. In particular, if the flow ratio of the gas to the liquid is lowered and only the liquid is jetted, there is a problem that the flow distribution shape in the spray width direction becomes unstable as shown in Conventional Example 2 of FIG.
[0005]
In response to demands for cost reduction, it is desired to reduce the flow ratio of gas to liquid (or to use only liquid) in order to save energy by suppressing the power consumption of the compressor that supplies gas. It is necessary to obtain a stable spray pattern even when the gas flow rate ratio is lowered, and the nozzles 1 and 5 cannot sufficiently meet the needs.
[0006]
In addition, due to a demand for a higher speed of a continuous casting machine, an improvement in cooling capacity by a nozzle is desired, and for that purpose, a nozzle capable of coping with an increase in an injection area and an increase in a liquid flow rate is required.
[0007]
The present invention has been made in view of the above problems, and provides a nozzle having a stable ejection pattern in which the variation in the ejection thickness and the ejection width is small even when the flow rate is changed, and further, the ejection area and the ejection flow rate are large. That is the task.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the present invention provides a method in which a tip of a large-diameter inflow hole along a center axis of a body communicates with a plurality of independent holes, and the plurality of independent holes are partitioned at symmetrical positions with respect to the center axis. While the injection side of each independent hole gradually reduces the flow path area and closes the tip,
A cutout portion cut in an arc shape or a tapered shape in the diameter direction is provided on the injection side end surface of the body, and the cutout portion cuts off the side surface on the central axis side of each of the independent holes, and the side surface and the bottom surface of the cutout portion A right-angled L-shaped nozzle opening at
The spray thickness of the fluids ejected from the nozzles formed opposite to both sides of the cut portion is increased by collision, and the fluid ejected from the nozzles inside the cut portion is cut off by the cuts. The nozzle is characterized in that the spray width is regulated by being guided by the insertion portion.
[0009]
With the above configuration, the fluid flowing out of the nozzles facing each of the independent holes collides and diffuses, so that the spray thickness can be increased. In addition, since the spray in the thickness direction is guided and sprayed on the side surface of the cut portion, it is possible to provide a stable spray thickness even when the flow rate changes.
Further, since the independent hole is provided with a front end closing portion having a reduced flow path area at a position before the injection port, the collision of the fluid is performed at a high speed and a high pressure, and the effect of diffusing the spray is enhanced.
[0010]
In addition, since the bottom surface of the cut portion is concavely formed in an arc shape or a tapered shape opened to the ejection side, the spray width direction of the fluid to be ejected is guided by the bottom surface of the cut portion, Even if the flow rate fluctuates, it is possible to provide a stable spray width. In particular, in the case of an arc shape, the spray is smoothly guided, thereby enabling the spray with little loss. Moreover, since the spray is sufficiently diffused as described above, the flow rate distribution in the spray width direction can be kept uniform even if the flow rate fluctuates.
[0011]
Furthermore, since the above-mentioned nozzle is formed in an L-shaped cross section in which the bottom surface and the side surface of the cut portion are perpendicular to each other, the opening of the nozzle can be enlarged as compared with a case where the cross section is linear or curved, for example, and the flow rate can be reduced. The upper limit can be increased. Further, the nozzle can be reduced in size because the nozzle can be enlarged without changing the body size.
[0012]
As described above, according to the nozzle of the present invention, the ejection pattern is stable even when the flow rate fluctuates. For example, when two fluids, liquid and gas, are supplied, the flow rate ratio of gas to liquid Even if the (air-water ratio) is lowered, the above nozzle can be used without replacing the nozzle. Therefore, a fluid supply pipe for supplying one or two fluids can be communicated with the inflow port of the inflow hole of the body, so that one or two fluids can be sprayed from the nozzle.
Further, since the air-water ratio can be reduced while maintaining a stable injection pattern, the power consumption of the gas supply compressor is suppressed, and energy saving can be achieved.
[0013]
The nozzle of each of the independent holes is formed by cutting out a side surface on the center axis side away from the tip closing portion of each of the independent holes, and the fluid returns from the tip closing portion of each of the independent holes to the nozzle. preferable.
[0014]
With the above configuration, the fluid ejected from each of the opposed injection ports slightly U-turns and flows in the return direction, so that the flow is stirred and the collision of the two flows can be increased. Can be sufficiently secured.
[0015]
Further, it is preferable that both side surfaces of the cut portion are inclined such that the leading end of the opening expands in the separating direction.
[0016]
With this configuration, the spray thickness stabilized between the side surfaces of the cut portion can be expanded and guided by the inclined tapered portion regardless of the magnitude of the flow rate.
[0017]
Two independent holes are provided at symmetrical positions with respect to the central axis, or four independent holes are provided at point-symmetrical positions with respect to the central axis.
[0018]
In particular, when a total of four independent holes are formed at point symmetric positions with respect to the central axis, the upper limit of the flow rate can be increased as a whole nozzle, and the fluid ejected from the nozzles of the opposed independent holes can be increased. Are performed at two points, and the spray thickness and the spray width can be increased.
[0019]
Further, when the central axes of the plurality of independent holes are parallel to the central axis of the body, or when two independent holes are provided side by side on one side of the cut portion, the central axes of these independent holes are aligned with the body. If the tip is inclined in the direction away from the center axis, the flow can be formed so as to spread in the spray width direction, so that the spray width can be increased.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 6 show a first embodiment.
1 (A) and 1 (B) show a connection mode of the nozzle 10, in which the nozzle 10 is externally fitted to the tip of the adapter 11, and a liquid pipe 12 is attached to a side surface of the adapter 11, so that the liquid pipe 12 and the liquid pipe 12 are formed in an L-shape. A check valve 14 is attached via an elbow 13 of the adapter, and the check valve 14 is used as a liquid supply port, while the rear end of the adapter 11 is used as a gas supply port.
[0021]
As shown in FIGS. 2 to 5, the nozzle 10 has a cylindrical inflow hole 16 formed in the rear end side of the body 15, and a partition wall 19 on the axis of the nozzle 10 is formed from the front end surface of the inflow hole 16. Independent holes 17 and 18 are provided along the axis of the nozzle 10.
The distal ends of the independent holes 17 and 18 form tapered distal end closing portions 17a and 18a, respectively, which gradually reduce the flow path area, and a notch 22 is recessed from the distal end of the body 15 on the injection side to close each distal end. Portions 17a and 18a are in communication with one opposite side. The openings of the distal end closing portions 17a, 18a communicated by the cutout portions 22 are injection holes 20, 21, respectively.
[0022]
The cut portion 22 has a bottom surface 22a concavely formed in an arc shape open to the ejection side, and a side surface 22b thereof is parallel to the axial direction of the nozzle 10. The radius of curvature R of the arc of the bottom surface 22a is in the range of 4 to 50 mm and is determined according to the body size and the required spray width.
[0023]
The injection ports 20 and 21 have an L-shaped cross section in which the bottom surface 22a and the side surface 22b of the cutout portion 22 are orthogonal.
As shown in FIG. 6 (A), the distal end closing portions 17a, 18a have a U-shaped portion 17b having a shape in which the fluid is U-turned back to the partition wall 19 from the distal ends of the independent holes 17, 18 to the injection ports 20, 21, 18b.
Further, a taper portion 23 is provided which extends in the separating direction continuously from the ejection-side tip of the side surface 22b of the cut portion 22.
[0024]
Next, a process of ejecting the fluid at the nozzle 10 will be described.
As shown in FIGS. 6A and 6B, the gas-liquid two-phase flow (hereinafter, referred to as a fluid) mixed by the adapter 11 is supplied to the inflow hole 16 of the nozzle 10 and is provided with two independent holes 17 and 18. Flow into each of them.
The fluid that has flowed into the independent holes 17 and 18 increases the flow velocity in accordance with the reduction in the flow path area at the distal end closure portions 17a and 18a, and the fluids that respectively flow out of the opposed injection ports 20 and 21 are cut into the cut portions 22. Collide within.
[0025]
The collision promotes the diffusion of the fluid in the spray thickness direction T and the spray width direction W. At this time, since the U-shaped portions 17b and 18b having a shape to return the fluid to the partition wall 19 side from the tips of the independent holes 17 and 18 to the injection ports 20 and 21 are provided slightly, the fluid ejected from each of the injection ports 20 and 21 slightly increases. Flowing in the return direction, the flow is stirred, and the collision of the two flows can be promoted. Even when the flow rate is small, the jet angle θn in the spray thickness direction T and the jet angle θw in the spray width direction W are sufficiently secured. can do.
[0026]
The colliding fluid is guided in the spray thickness direction T by the side surface 22b of the cut portion 22 and the spray width direction W is smoothly guided by the arc-shaped bottom surface 22a of the cut portion 22. Therefore, it is possible to provide a stable spray angle θn in the spray thickness direction T and a spray angle θw in the spray width direction W even when the flow rate fluctuates.
In particular, in the spray width direction W, the bottom surface 22a of the cut portion 22 serving as a guide wall is formed in an arc shape, thereby enabling spray with little energy loss.
[0027]
Finally, regardless of the flow rate, the spray in the spray thickness direction T stabilized between the side surfaces 22b of the cut portions 22 is guided by the tapered portion 23 that is continuous from the side surfaces 22b of the cut portions 22 to the tip side. To increase the injection angle θn.
[0028]
As described above, since the spray is sufficiently diffused, the flow rate distribution in the spray width direction W can be kept uniform even if the flow rate fluctuates.
Further, since the injection ports 20 and 21 have an L-shaped cross section in which the bottom surface 22a and the side surface 22b of the cut portion 22 are orthogonal to each other, the openings of the injection ports 20 and 21 can be enlarged, and the upper limit of the flow rate can be increased. Since the nozzles 20 and 21 can be enlarged without changing the size of the body 15, the size of the nozzle 10 can be reduced.
[0029]
Moreover, according to the nozzle 10 of the present invention, since the injection pattern is stable even when the flow rate fluctuates, the flow rate ratio (gas-water ratio) of gas to liquid can be reduced, and the power of the gas supply compressor can be reduced. Consumption is also reduced, and energy savings can be achieved.
For example, the turndown ratio, which is the range in which the liquid flow rate can be increased or decreased while maintaining the ejection pattern, is about 1:15 (ex. Liquid flow rate of 1 to 15 L / min) in the conventional two-fluid nozzle, and 1 in the conventional one-fluid nozzle. : 3, the turndown ratio can be increased to 1:25 in the one-fluid / two-fluid nozzle 10 of the present invention.
[0030]
In addition, since the injection pattern is stable even if the flow rate ratio of gas to liquid (air-water ratio) is reduced, it is possible to cope with this nozzle 10 alone without replacing the nozzle, and to use the one-fluid nozzle (liquid only). ).
[0031]
Next, the injection patterns of the nozzle 10 of the first embodiment of the present invention and the nozzles 1 and 5 of Conventional Example 1 (FIG. 14) and Conventional Example 2 (FIG. 15) will be compared and considered.
FIG. 7 is a table comparing the flow rate distributions of the nozzle 10 of the first embodiment of the present invention and Conventional Examples 1 and 2.
[0032]
The injection angle θn of the nozzle 1 of the conventional example 1 in the injection thickness direction T is θn = 20 ° when two fluids of water and air are used, but θn = 6 ° when one fluid of only water is used. °, and when the air-water ratio is largely changed, a stable injection pattern cannot be obtained.
The injection angle θw in the injection width direction W by the nozzle 5 of Conventional Example 2 is θw = 78 ° when two fluids of water and air are used, but θn = 90 ° when one fluid only of water is used. In addition, the flow rate distribution shape shows a wave-shaped non-uniform distribution, and a stable injection pattern cannot be obtained when the air-water ratio is largely changed.
[0033]
According to the nozzle 10 of the present invention, the injection angle θn in the injection thickness direction T when using two fluids of water and air is 60 °, and the injection angle θn when using one fluid only with water is also 60 °. Even if the air-water ratio fluctuates, the flow rate distribution fluctuates little and is stable.
In addition, the injection angle θw in the injection width direction W when using two fluids of water and air is 115 °, and the injection angle θw when using one fluid including only water is 115 °, which is stable with little fluctuation. In addition, a uniform distribution shape can be obtained even when the air-water ratio is reduced and only water is used.
[0034]
FIG. 8 shows a second embodiment.
The difference from the first embodiment is that the bottom surface 22a 'of the cut portion 22' is tapered so as to expand toward the injection side instead of having an arc shape.
With the above configuration, as in the first embodiment, the fluid that has flowed out of the nozzles 20 and 21 and collided is guided by the inclined bottom surface 22a ′ of the notch 22 ′, so that the fluid is stable even when the flow rate fluctuates. The spray angle θw in the spray width direction W can be provided.
Note that the other configuration is the same as that of the first embodiment, and the description is omitted.
[0035]
FIG. 9 shows a third embodiment.
The difference from the first embodiment is that a concave portion 19a 'having an arc-shaped cross section is provided at the tip of the partition wall 19'.
With the above configuration, the space of the concave portion 19a 'functions as a stirring chamber for the fluid flowing out of the injection ports 20, 21, and the diffusion of the spray can be enhanced.
Note that the other configuration is the same as that of the first embodiment, and the description is omitted.
[0036]
FIG. 10 shows a fourth embodiment.
The difference from the first embodiment is that a projection 19a "having an arc-shaped cross section protrudes from the tip of the partition wall 19".
With the above configuration, the flow path on the downstream side of the nozzles 20 and 21 is narrowed, the collision pressure of the fluid flowing out from the opposed nozzles 20 and 21 is increased, and the diffusion of the spray can be enhanced.
Note that the other configuration is the same as that of the first embodiment, and the description is omitted.
[0037]
FIG. 11 shows a fifth embodiment.
The difference from the first embodiment is that the distal ends of the independent holes 17 'serving as the distal end closing portions 17a' and 18a 'do not have a U-shaped portion. That is, the distal end closing portions 17a 'and 18a' smoothly communicate with the cut portion 22 as they are.
Note that the other configuration is the same as that of the first embodiment, and the description is omitted.
[0038]
FIG. 12 shows a sixth embodiment.
The difference from the first embodiment is that four independent holes 17-1, 17-2, 18-1, and 18-2 are arranged at point-symmetric positions with respect to the central axis.
With the above configuration, a total of four independent holes 17-1, 17-2, 18-1, 18-2 are formed, so that the upper limit of the flow rate of the nozzle 10 as a whole can be increased, and the opposed independent holes are formed. The collision of the fluid ejected from the nozzles 20-1, 21-1, 20-2, and 21-2 of the holes 17-1 and 18-1 and 17-2 and 18-2 is performed at two places, and the spray thickness and Spray width can be increased.
Note that the other configuration is the same as that of the first embodiment, and the description is omitted.
[0039]
FIG. 13 shows a seventh embodiment.
The difference from the sixth embodiment is that the center axes of the two independent holes 17-1 ′ and 17-2 ′ disposed on one side of the partition wall 19 are separated from each other with the center axis of the body 15 interposed therebetween. The point is that it is inclined in the direction.
With the above configuration, the flow of the fluid can be formed so as to diffuse in the spray width direction T, so that the spray width can be increased.
The other configuration is the same as in the sixth embodiment, and a description thereof will not be repeated.
[0040]
【The invention's effect】
As is clear from the above description, according to the nozzle of the present invention, the spray thickness and the spray width can be increased by colliding and diffusing the fluid flowing out from the opposed nozzles of the respective independent holes. . In addition, since the spray is guided and sprayed on the side surface and the arc-shaped bottom surface of the cut portion, a stable spray thickness and a spray width can be obtained even if the flow rate fluctuates, and the flow rate distribution is uniform. Can be kept.
Further, since the independent hole is provided with a front end closing portion having a reduced flow path area at a position before the injection port, the collision of the fluid is performed at a high speed and a high pressure, and the effect of diffusing the spray can be enhanced.
[0041]
In addition, since the above-mentioned injection port has an L-shaped cross section in which the bottom surface and the side surface of the cut portion are perpendicular to each other, the opening area can be increased, the upper limit of the flow rate can be increased, and the nozzle can be downsized.
Furthermore, since the ejection pattern is stable even if the flow rate fluctuates, even if the flow rate ratio (gas-water ratio) of the gas to the liquid is lowered, it can be used without replacing the nozzle, and it can be used for one fluid. The nozzle can be used for two fluids.
In addition, since the gas-water ratio can be reduced, the power consumption of the gas supply compressor is also suppressed, and energy saving can be achieved.
[0042]
In addition, by providing the U-shaped portion from the tip of the independent hole to the injection port, the fluid ejected from each of the opposed injection ports slightly flows in the return direction and is stirred, and the collision of the two flows can be increased, Even when the flow rate is small, a sufficient spray area can be secured.
[Brief description of the drawings]
FIG. 1A is a side view showing a use mode of a nozzle according to a first embodiment of the present invention, and FIG. 1B is a front view.
FIG. 2 is a cross-sectional view of the nozzle according to the first embodiment.
FIG. 3 is a cross-sectional view in a direction orthogonal to FIG.
FIG. 4 is a front view of the ejection side of the nozzle according to the first embodiment.
FIG. 5 is a rear view of the nozzle of the first embodiment on the inflow side.
6A is an enlarged cross-sectional view of a main part of FIG. 2, and FIG. 6B is an enlarged cross-sectional view of a main part of FIG.
FIG. 7 is a table showing a comparison of a flow rate distribution between the nozzle of the first embodiment and a conventional example.
FIG. 8 is a sectional view of a nozzle according to a second embodiment.
FIG. 9 is a sectional view of a main part of a nozzle according to a third embodiment.
FIG. 10 is a sectional view of a main part of a nozzle according to a fourth embodiment.
FIG. 11 is a sectional view of a main part of a nozzle according to a fifth embodiment.
FIG. 12A is a sectional view of a nozzle according to a sixth embodiment, and FIG. 12B is a front view.
FIG. 13 is a sectional view of a nozzle according to a seventh embodiment.
FIG. 14 is a sectional view of a nozzle of Conventional Example 1.
FIG. 15 is a cross-sectional view of a nozzle of Conventional Example 2.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Nozzle 11 Adapter 12 Liquid pipe 13 Elbow 14 Check valve 15 Body 16 Inflow hole 17, 18 Independent hole 17a, 18a Tip closing part 17b, 18b U-shaped part 19 Partition wall 20, 21 Injection opening 22 Cut part 22a Bottom surface 22b Side surface 23 Taper Department

Claims (6)

The distal end of the large-diameter inflow hole along the center axis of the body is communicated with a plurality of independent holes, and the plurality of independent holes are formed at positions symmetrical with respect to the center axis via a partition wall. While the injection side of the hole gradually reduces the flow path area and closes the tip,
A cutout portion cut in an arc shape or a tapered shape in the diameter direction is provided on the injection side end surface of the body, and the cutout portion cuts off the side surface on the central axis side of each of the independent holes, and the side surface and the bottom surface of the cutout portion A right-angled L-shaped nozzle opening at
The spray thickness of the fluids ejected from the nozzles formed opposite to both sides of the cut portion is increased by collision, and the fluid ejected from the nozzles inside the cut portion is cut off by the cuts. A nozzle characterized in that the spray width is regulated by a guide portion. The nozzle of each of the independent holes is formed by cutting out a side surface on the central axis side away from the tip closing part of each of the independent holes, and fluid is returned to the nozzle from the tip closing part of each of the independent holes. Item 2. The nozzle according to Item 1. 3. The nozzle according to claim 1, wherein both side surfaces of the cut portion are inclined so that an opening tip expands in a separating direction. 4. 4. The nozzle according to claim 1, wherein two of the independent holes are provided at symmetrical positions with respect to the central axis, or four of the independent holes are provided at point-symmetrical positions with respect to the central axis. 5. The central axis of the plurality of independent holes is parallel to the central axis of the body, or when two independent holes are provided side by side on one side of the cut portion, the central axes of the independent holes are aligned with the central axis of the body. 5. The nozzle according to claim 4, wherein the tip is inclined in the separating direction with respect to the nozzle. A fluid supply pipe for supplying one or two fluids is communicated with an inflow port of the inflow hole of the body, so that one or two fluids can be sprayed from the orifice. Nozzle according to item.

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