JPH11217661A - Gas injection nozzle device for regulating plating thickness - Google Patents

Abstract

PROBLEM TO BE SOLVED: To rapidly change the nozzle hole shape of a gas injection nozzle to an optimum shape without stopping operation. SOLUTION: The first rear surface 14 of an upper nozzle body 10 forms the front surface of the nozzle hole 6. A nozzle hole regulating piece 8 is attachably and detachably inserted via a positioning projecting part 26 and a positioning recessed part 43 to a lower nozzle body 11. The third front surface 47 of the nozzle hole regulating piece 8 forms the rear surface of the nozzle hole 6. A wedge piece 9 is attachably and detachably inserted between the lower nozzle body 11 and the nozzle hole regulating piece 8 and presses and fixes the nozzle hole regulating piece 8 to the lower nozzle body 11 by its wedge effect. Since the nozzle hole regulating piece 8 is rapidly attachable and detachable by the simple operation, the exchange of the nozzle hole regulating piece 8 is made possible without stopping the operation. As a result, the nozzle hole shape may be changed to the optimum shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas injection nozzle device for adjusting a plating thickness of a metal strip which is continuously hot-dipped.

[0002]

2. Description of the Related Art Conventionally, when hot dip plating is continuously performed on a metal strip, for example, a steel strip, the amount of plating applied has been controlled by a gas wiping method. The gas wiping method is a method in which excess plating metal attached to a steel strip is blown off by the pressure of a gas injected from a gas injection nozzle, whereby the amount of plating applied can be controlled to a predetermined value, Beautiful surface skin can be obtained. When this gas wiping method is used, the length of the gas injection nozzle extending in the width direction of the steel strip is configured to be longer than the width of the steel strip. As a result, a buffer flow is generated. This buffer flow impairs the wiping effect at the width end of the steel strip, causing a problem that the amount of plating applied to the width end of the steel strip increases (hereinafter, referred to as edge overcoat). For this reason, a method is provided in which an auxiliary nozzle capable of following the width of the steel strip is provided at the width end of the steel strip, and the wiping gas pressure is increased only at the width end of the steel strip to prevent edge overcoating. In this method, there is a problem that it becomes difficult to cope with an increase in the amount of plating.

As another method, a taper is formed in the nozzle hole of the gas injection nozzle, the interval between both ends of the nozzle hole is made larger than the center portion, and the flow rate of the injection gas at both ends is increased to form an edge overcoat. There have been ways to prevent this. In this method, if a taper is formed in the nozzle hole so as to fit a narrow steel strip, the taper is incompatible with a wide steel strip. And the distribution of the attached amount in the width direction becomes non-uniform. For this reason, it is necessary to design an appropriate taper for each steel strip width, and replace the gas injection nozzle with an appropriate taper according to the manufacturing width. In this case,
Since it takes a long time to replace the nozzle, it is necessary to stop the operation, and there is a problem that productivity is greatly reduced. In order to solve such a conventional problem, the following prior art is disclosed.

Japanese Patent Publication No. 52-32330 relates to an injection opening of an injection nozzle device for blowing away excess plated metal. In this publication, a lip is provided between an upper lip and a lower lip forming an injection opening, a screw that penetrates the upper lip in a vertical direction and is screwed to the lip, and a nut that is screwed to the screw The upper lip is provided in a plurality of lengthwise directions, the lip is vertically displaced by a screw and a nut, and the interval between the pressure gas passage openings formed between the lip and the lower lip can be adjusted. The configuration of the injection opening is disclosed.

Japanese Patent Publication No. 60-58785 relates to a nozzle header of a continuous hot-dip plating apparatus. In this publication, a plurality of gas injection nozzles are provided on the outer peripheral surface of a cylindrical nozzle header, and the gas injection nozzle is rotated at the same time as the rotation of the cylindrical nozzle header. A configuration of a nozzle header that selectively uses an ejection nozzle is disclosed.

[0006]

[Problems to be solved by the invention] Japanese Patent Publication No. 52-3233
According to the prior art disclosed in Japanese Patent Publication No. 0, since a plurality of screws and nuts for adjusting the interval between the pressure gas passage openings are provided in the longitudinal direction of the upper lip, that is, in the width direction of the metal band, metal Even if the width of the strip changes, the shape of the pressure gas passage opening can be adjusted without replacing the gas injection nozzle. On the other hand, in this prior art, since it is necessary to adjust a plurality of screws and nuts according to the width of the metal strip, there is a problem that it takes a long time for the adjustment and the operation must be stopped.

According to the prior art disclosed in Japanese Patent Publication No. 60-58785, a plurality of gas injection nozzles are configured to be selectable by a rotating operation.
The gas injection nozzle can be replaced without stopping the operation. On the other hand, in this prior art, there is a limit to the number of gas injection nozzles that can be installed on the outer peripheral surface of the cylindrical nozzle header. Therefore, there is a problem that an optimum gas injection nozzle cannot be provided over the entire width range of the metal strip. is there.

An object of the present invention is to provide a plating thickness adjusting gas injection nozzle device which can change the nozzle hole shape of the gas injection nozzle to an optimum shape in a short time without stopping the operation.

[0009]

According to the present invention, a metal strip is conveyed above a bath surface of a hot-dip galvanized metal, on both sides of a plate surface of a metal strip which is conveyed almost vertically upward through the bath. Injection gas from the nozzle holes of a pair of gas injection nozzles provided as a gas injection nozzle device for adjusting the plating thickness to blow off the excess plating metal plated on the metal strip, A nozzle body having one of them and forming one inner surface of a nozzle hole extending in the width direction of the metal band, and a positioning recess or a positioning protrusion contacting one of the positioning protrusion or the positioning recess of the nozzle body. A nozzle hole adjusting piece detachably inserted into the nozzle body and forming the other inner surface of the nozzle hole, and a positioning convex portion or a positioning concave portion of the nozzle hole adjusting piece, the position of the nozzle body. A plating thickness regulating gas injection nozzle device which comprises a pressing means for pressing the projections or positioning recesses decided.

According to the present invention, since the nozzle hole adjusting piece that forms the other inner surface of the nozzle hole is detachably inserted, the nozzle hole adjusting piece can be replaced without stopping the operation. In addition, if a large number of nozzle hole adjusting pieces having different shapes are prepared, the optimum nozzle hole adjusting piece can be selected according to the width of the metal strip, so that the nozzle hole shape can be changed to the optimum shape. it can.

The pressing means of the present invention is a tapered wedge piece extending in the width direction of the metal strip, and the wedge piece is removably inserted between the nozzle body and the nozzle hole adjustment piece. It is characterized by the following.

According to the present invention, since the pressing means is a tapered wedge piece, the nozzle hole adjusting piece can be fixed / opened with respect to the nozzle body by a simple pushing / pulling operation. Therefore, the nozzle hole adjusting piece can be replaced in a short time.

The base end and the tip of the wedge piece of the present invention project outward from both ends of the nozzle body in the inserted state, and the tip of the projected wedge piece has a nozzle hole adjusting piece. Is provided.

According to the present invention, since the detachable guide for the nozzle hole adjusting piece is provided near the tip of the wedge piece, the long nozzle hole adjusting piece can be smoothly attached and detached. Therefore, the nozzle hole adjusting piece can be replaced in a shorter time.

[0015] The pressing means of the present invention further comprises an eccentric member whose distance between the axis and the outer peripheral surface increases and decreases along the circumferential direction.
The eccentric member is provided between the nozzle body and the nozzle hole adjusting piece, and is characterized in that it can be angularly displaced around the axis.

According to the present invention, since the pressing means is an eccentric device having an eccentric member capable of angular displacement, the nozzle hole adjusting piece is fixed to the nozzle body by a simple angular displacement operation.
Can be opened. Therefore, the nozzle hole adjusting piece can be replaced in a short time.

The nozzle body according to the present invention includes an upper nozzle body having a nozzle inner surface defining an upper surface of a nozzle hole;
A lower nozzle body that has one of a positioning protrusion or a positioning recess, and is integrally fixed to the upper nozzle body, and is interposed between mutual contact surfaces of the upper nozzle body and the lower nozzle body. And a shim made of a metal softer than the material of the nozzle body.

According to the present invention, the nozzle body is divided into upper and lower two parts, and a metal shim is provided between the upper nozzle body and the lower nozzle body. The vertical spacing of the nozzle holes can be adjusted to a predetermined value. Also, since a metal shim that is softer than each nozzle body is provided, when tightening the upper nozzle body and the lower nozzle body with bolts,
The tightening force can be equalized over the entire contact surface, and rattling between the upper nozzle body and the lower nozzle body after the tightening can be prevented.

[0019]

FIG. 1 is a side view showing a simplified structure of a gas injection nozzle of a gas injection nozzle device for plating thickness adjustment according to an embodiment of the present invention, and FIG. 2 is shown in FIG. FIG. 3 is a plan view of a gas injection nozzle, and FIG. 3 is a side view showing a simplified configuration of a gas injection nozzle device for plating thickness adjustment according to an embodiment of the present invention. The plating thickness adjusting gas injection nozzle device 1 is configured to include a pair of gas injection nozzles 3 having the same configuration. The pair of gas injection nozzles 3 oppose each other across a metal strip, for example, a steel strip 5 which passes through the bath at the same position on the bath surface of the hot-dip galvanized metal, for example, hot-dip zinc 4, and is conveyed almost vertically upward. It is provided. A pair of gas injection nozzles 3 injects gas from the nozzle holes 6 on both sides of the steel strip 5 on the plate surface, blows away excess molten zinc 4 plated on the steel strip 5, and removes the plating thickness, that is, the zinc adhesion amount. To adjust. The gas to be injected is air, nitrogen, combustion exhaust gas, or the like. In the present embodiment, air is used.

The gas injection nozzle 3 includes a nozzle body 7, a nozzle hole adjusting piece 8, and a wedge piece 9 as a pressing means. The nozzle body 7 is divided into upper and lower parts with the nozzle hole 6 as a boundary, and the upper nozzle body 10 and the lower nozzle body 1 are divided.
1 and a shim 68. Upper nozzle body 10
Is a member extending in the width direction of the steel strip 5 (hereinafter, abbreviated as the width direction), and its cross section perpendicular to the axis is substantially a beak shape. The tip portion 13 of the upper nozzle body 10 is provided facing the steel strip 5, and the first lower surface 14 of the tip portion 13 is formed substantially parallel to a horizontal plane. The first lower surface 14 forms one inner surface of the nozzle hole 6, that is, the upper surface of the nozzle hole 6. The outer surface 40 facing the steel strip 5 near the tip portion 13 is inclined downward as approaching the steel strip 5. The inclination angle is set to a predetermined angle.

The upper nozzle body 10 has the first lower surface 14
Are formed, and a gas supply path 16 is formed. The groove 15 is formed in the first lower surface 14 and extends in the width direction, and forms a gas supply chamber as described later. The gas supply path 16 is a communication hole that communicates the notch groove 19 formed in the rear end face 18 of the upper nozzle body 10 with the groove 15, and a plurality of gas supply paths 16 are formed at intervals in the width direction.
The second lower surface 20 of the rear end portion 17 of the upper nozzle body 10 is formed substantially parallel to a horizontal plane, and is present in the same plane as the first lower surface 14. A first bolt insertion hole 21 extending in the vertical direction and a second bolt insertion hole 22 extending in the horizontal direction are formed in the rear end portion 17 of the upper nozzle body 10.
End face covers 39 are provided on the end faces at both ends in the width direction of the upper nozzle body 10, as shown in FIG.

FIG. 4 is a simplified perspective view showing the structure of the lower nozzle body 11 shown in FIG. Lower nozzle body 11
Is a member extending in the width direction, and has a substantially beak-like cross-sectional shape perpendicular to the axis as shown in FIGS. The distal end portion 23 of the lower nozzle body 11 is provided facing the steel strip 5, and a first upper surface 24, which is the upper surface of the distal end portion 23, is formed substantially parallel to a horizontal plane. Since the first upper surface 24 forms a positioning surface of the nozzle hole adjusting piece 8 as described later,
Hereinafter, it is referred to as a first positioning surface 24. First positioning surface 24
Has a shallow groove 25 extending in the width direction.

The tip 23 of the lower nozzle body 11 has a substantially V
A positioning protrusion 26 having a U-shape is formed, and a fitting groove 29 extending in the width direction is formed between the front end 23 and the rear end 28 of the lower nozzle body 11. The positioning projection 26 projects into the fitting groove 29 as shown in FIG. 4 and extends in the width direction. The positioning projection 26 is
It has the first positioning surface 24, the second positioning surface 27, and the top surface 30, and the second positioning surface 27 is inclined downward as approaching the steel strip 5. First positioning surface 24
Is an acute angle with the second positioning surface 27.
The first side surface 33 on the distal end portion 23 side of the fitting groove 29 and the top surface 30 are formed so as to be substantially parallel to the plate surface of the steel strip 5. On the other hand, the rear end 2 of the fitting groove 29
The 8th second side surface 34 is inclined with respect to the plate surface of the steel strip 5, and the inclined surface in this embodiment is from one end to the other end in the width direction of the steel strip 5, that is, from above in FIG. 2. It is formed so as to approach the plate surface downward.

The bottom surface 31 of the fitting groove 29 is formed substantially parallel to a horizontal plane. The outer surface 41 of the distal end portion 23 of the lower nozzle body 11 facing the steel strip 5 is inclined upward as approaching the steel strip 5. The inclination angle is set to a predetermined angle. A plurality of third bolt insertion holes 36 extending in the vertical direction and a plurality of fourth bolt insertion holes 37 extending in the horizontal direction are formed in the rear end portion 28 of the lower nozzle body 11 at intervals in the width direction. The third bolt insertion hole 36 is formed at a position corresponding to the first bolt insertion hole 21. The second upper surface 35 of the rear end portion 28 of the lower nozzle body 11 is formed substantially parallel to a horizontal plane. The shim 68 will be described later.

FIG. 5 is a simplified perspective view showing the structure of the nozzle hole adjusting piece shown in FIG. The nozzle hole adjusting piece 8
It is a member extending in the width direction, and its cross-section perpendicular to the axis is substantially L-shaped. The lower part of the nozzle hole adjusting piece 8 has a substantially V
A letter-shaped positioning recess 43 is formed. The positioning recess 43 includes a third positioning surface 44 that contacts the first positioning surface 24 and a fourth positioning surface 44 that contacts the second positioning surface 27.
It has a positioning surface 45 and a valley bottom surface 51. The third positioning surface 44 is a third lower surface of the tip end portion 46 of the nozzle hole adjusting piece 8 and is formed substantially horizontally on a horizontal plane.
The fourth positioning surface 45 is inclined downward as approaching the steel strip 5. The angle between the third positioning surface 44 and the fourth positioning surface 45 is an acute angle, and is equal to the angle α between the first positioning surface 24 and the second positioning surface 27. Therefore, the nozzle hole adjusting piece 8 can slide in the width direction by bringing the corresponding positioning surfaces of the positioning concave portion 43 and the positioning convex portion 26 into contact with each other. Also, as shown in FIG. 1, the nozzle hole adjusting piece 8 can be inserted into and attached to the lower nozzle main body 11 as shown in FIG. Since the sliding surface is a surface, wear of the sliding surface can be reduced. Furthermore, the first positioning surface 24
The shallow groove 25 is formed in the first positioning surface 24
And the third positioning surface 44 can be brought into uniform contact.

The third upper surface 47 of the tip end portion 46 of the nozzle hole adjusting piece 8 forms the other inner surface of the nozzle hole 6, that is, the lower surface of the nozzle hole 6 at the time of the mounting. The shape of the third upper surface 47 will be described later. Tip 46 of nozzle hole adjusting piece 8
The outer surface 54 facing the steel strip 5 is inclined upward at a predetermined angle as approaching the steel strip 5. This outer surface 54
The outer surface 41 of the lower nozzle main body 11 is substantially in the same plane as the outer surface 41. Fourth upper surface 49 of rear end portion 48 of nozzle hole adjusting piece 8
Is formed with a step below the third upper surface 47, and forms a gas supply chamber as described later. The fourth upper surface 49 and the fourth lower surface 50 of the rear end portion 48 are formed substantially parallel to a horizontal plane. Bottom surface 51 of positioning recess 43, third side surface 52 continuing to fourth positioning surface 45
The rear end side fourth side surface 53 of the nozzle hole adjusting piece 8 is formed substantially parallel to the plate surface of the steel strip 5. The length of the nozzle hole adjusting piece 8 in the width direction is formed longer than the lower nozzle main body 11 as shown in FIG. Therefore, the nozzle hole adjusting piece 8 at the time of the mounting protrudes outward at both ends of the width of the lower nozzle body 11.

The dimensions of the positioning projection 26 and the positioning recess 43 are as shown in FIG.
0 and the valley bottom surface 51 so as not to contact with each other, and the first side surface 3
3 and the third side surface 52 so as not to contact with each other, and
The bottom surface 31 of the nozzle 9 and the fourth lower surface 50 of the nozzle hole adjusting piece 8 are set so as not to contact with each other. As described above, the nozzle hole adjusting piece 8 and the lower nozzle main body 11 are configured so as to abut only on the corresponding positioning surface but not in other parts, so that the positioning of the nozzle hole adjusting piece 8 can be accurately performed. Can be done.

FIG. 6 is a front view showing the shape of the nozzle hole as viewed from the plate surface of the steel strip. The nozzle hole 6 is a gas injection space that extends in the width direction, that is, in the left-right direction in FIG. 6, and the upper nozzle body 1 that defines the upper surface of the nozzle hole 6 as described above.
The first lower surface 14 (hereinafter, referred to as the nozzle hole upper surface) and the third upper surface 47 (hereinafter, referred to as the nozzle hole lower surface) of the nozzle hole adjusting piece 8 that defines the lower surface of the nozzle hole 6. The shape of the nozzle hole lower surface 47 is not flat but trapezoidal. That is, the regions E1 and E5 near the both ends in the width direction of the nozzle hole adjusting piece 8 are formed on flat surfaces substantially parallel to the horizontal plane, and the region E3 in the center portion in the width direction is formed.
Is formed on a flat surface above the regions E1 and E5 and substantially parallel to the horizontal plane. On the contrary,
The intermediate regions E2 and E4 are formed as tapered surfaces that are inclined upward toward the center in the width direction. As described above, since the nozzle hole upper surface 14 is formed substantially parallel to the horizontal plane, the interval between the nozzle holes 6 becomes the minimum interval G1 in the width direction central region E3, and the interval increases toward both ends in the width direction. Regions E1 and E5 near both ends in the width direction
Becomes the maximum interval G2. The division of the regions E1 to E5 and the difference between the maximum interval G2 and the minimum interval G1, that is, the gradient of the taper, are set in advance according to the sheet width of the steel strip 5, the type of hot-dip metal, and the like.

FIG. 7 is a simplified perspective view showing the structure of the wedge piece shown in FIG. The wedge piece 9 is a tapered rectangular rod-shaped body extending in the width direction, and the fourth side face 53 of the nozzle hole adjusting piece 8.
A fifth side surface 55 that contacts the second side surface 34 of the fitting groove 29 of the lower nozzle body 11, a fifth side surface 57 that contacts the bottom surface 31 of the fitting groove 29, 5 upper surface 58. The fifth side surface 55 is formed substantially parallel to the plate surface of the steel strip 5, and the fifth lower surface 57 and the fifth upper surface 58 are formed substantially parallel to a horizontal plane. On the other hand, the sixth side surface 56 is inclined so as to approach the steel strip 5 from one end in the width direction to the other end. Fifth side 5
The angle θ between the fifth side and the sixth side 56 is the same as the inclination angle of the fitting groove 29 with respect to the plate surface of the second side 34. Therefore, the wedge piece 9 is in contact with the fourth side face 53 of the nozzle hole adjustment piece 8,
It can be removably inserted between the lower nozzle body 11 and the second side surface 34. When the wedge piece 9 is inserted and pushed toward the other end in the width direction, and the fifth side face 55, the sixth side face 56, and the fifth lower face 57 are brought into contact with the corresponding contact surfaces, the wedge piece is formed. 9 can apply a pressing force in a direction perpendicular to the plate surface of the steel strip 5 to the nozzle adjusting piece 8 by a wedge effect. As a result, the nozzle adjustment piece 8 can be securely fixed to the lower nozzle main body 11 via the positioning projection 26 and the positioning recess 43. Further, if the wedge piece 9 is pulled out in the width direction, the pressing force can be released, so that the nozzle adjustment piece 8 can be easily pulled out. in this way,
Since the nozzle hole adjusting piece 8 can be fixed and opened by a simple operation, the nozzle hole adjusting piece 8 can be quickly replaced in a short time. Fifth upper surface 58 of wedge piece 9
The fourth upper surface 49 of the groove 15 and the nozzle hole adjusting piece 8
At the same time, a gas supply chamber is formed.

The length of the wedge piece 9 is formed longer than the length of the lower nozzle body 11, as shown in FIG. Therefore, in the inserted state, the base end portion 60 and the tapered distal end portion 61 of the wedge piece 9 protrude outward from both end portions in the width direction of the lower nozzle main body 11. An attachment / detachment guide 63 is provided at the tip 61 of the projecting wedge piece 9.
Are attached to the lower surface 57 of the wedge piece 9 by fixing bolts 64. The base end portion 60 and the front end portion 61 of the wedge piece 9
Locking hole 6 for locking the jig when inserting and withdrawing wedge piece 9
5 are formed. The upper nozzle body 10, the lower nozzle body 11, the nozzle hole adjusting piece 8 and the wedge piece 9 are all made of the same steel type steel material, for example, chromium molybdenum steel.

A second lower surface 20 of the upper nozzle body 10,
Lower nozzle body 11 which is a contact surface corresponding to second lower surface 20
As shown in FIG. 1, a shim 68
Is provided. The shim 68 is a thin plate made of a metal softer than the upper nozzle main body 10 and the lower nozzle main body 11, for example, brass. As described above, since the nozzle body 7 is vertically divided and the shim 68 is provided between the upper and lower nozzle bodies 10 and 11, the minimum distance G1 between the nozzle holes 6 can be adjusted to a predetermined value. Also, since the shim 68 is softer than the upper nozzle body 10 and the lower nozzle body 11, bolts are inserted through the first bolt insertion hole 21 and the third bolt insertion hole 36, and the upper nozzle body 10 and the lower nozzle body 11 When the bolts are integrally fixed, the bolt tightening force can be equalized over the entire contact surface, and rattling after the tightening can be prevented.

After assembling the upper nozzle body 10 and the lower nozzle body 11 via the shim 68 as described above, the gas injection nozzle 3 is assembled by positioning the nozzle hole adjusting piece 8 with the positioning projection 26 and the positioning projection 26. This is performed by inserting the recess 43 into contact with the lower nozzle main body 11 and further inserting the wedge piece 9 to fix the nozzle hole adjusting piece 8 to the lower nozzle main body 11. The assembled gas injection nozzle 3 is attached to a nozzle header (not shown) by bolts inserted into the second and fourth bolt insertion holes 22 and 37. The gas supplied from the nozzle header passes through the gas supply path 16, the gas supply chamber, and the nozzle holes 6 in this order, and is sprayed on the plate surface of the steel strip 5. To replace the nozzle hole adjusting piece 8, the wedge piece 9 is displaced toward one end in the width direction to release the pressing force, the nozzle hole adjusting piece 8 is extracted, and another nozzle hole adjusting piece 8 is replaced with the lower nozzle by the same procedure. This is performed by inserting it into the main body 11. Note that the displacement of the wedge piece 9 for releasing the pressing force may be small, and the insertion and removal of the nozzle hole adjustment piece 8 is performed by mounting the other end of the nozzle hole adjustment piece 8 on the detachable guide table 63. This is carried out by placing it and moving it in the width direction.

As described above, since the nozzle hole adjusting piece 8 can be quickly replaced by a simple operation, there is no need to stop the operation at the time of replacement. Therefore, productivity can be significantly improved. If a large number of nozzle hole adjusting pieces 8 having different shapes of the nozzle hole lower surface 47 are prepared,
Since the optimum nozzle hole adjusting piece 8 can be selected according to the plate width of the steel strip 5, the nozzle hole shape can be changed to the optimum shape by replacement. As a result, gas wiping can always be performed with the optimum nozzle hole shape. Therefore, it is possible to achieve both prevention of edge overcoat and uniformization of the distribution of the attached amount in the width direction.

Further, since the positioning of the nozzle hole adjusting piece 8 is performed by pressing the positioning concave portion 43 against the positioning convex portion 26 by the pressing force of the wedge piece 9, the nozzle hole adjusting piece 8 is surely positioned at a predetermined position. It can be fixed accurately. Therefore, the nozzle hole adjustment piece 8 during operation
The rattling can be prevented, and the widthwise opening degree distribution of the nozzle holes 6 can be accurately set to a predetermined value. Further, since the nozzle body 7, the nozzle hole adjusting piece 8 and the wedge piece 9 are made of the same steel material, the coefficient of thermal expansion is the same, and it is difficult to attach and detach the nozzle hole adjusting piece 8 and the wedge piece 9 due to the difference in the coefficient of thermal expansion. Can be avoided. In addition, since a detachable guide for the nozzle hole adjusting piece 8 is provided near the distal end portion 61 of the wedge piece 9, the nozzle hole adjusting piece 8 can be smoothly attached and detached.

As described above, in this embodiment, the nozzle body 7 is divided into upper and lower parts with the nozzle hole 6 as a boundary, but the nozzle body 7 may be formed integrally without dividing. In the present embodiment, the lower nozzle body 11
The positioning protrusions 26 are formed on the lower nozzle main body 11, and the positioning recesses 43 are formed on the nozzle hole adjusting pieces 8.
The positioning convex part 26 may be formed in the first position.
Further, in the present embodiment, although the lower nozzle main body 11 is provided with the nozzle hole adjusting piece 8 and the wedge piece 9, the upper nozzle main body 10 may be provided with them.

FIG. 8 is a simplified side view showing the structure of a gas injection nozzle according to another embodiment of the present invention.
FIG. 9 is a plan view of the gas injection nozzle shown in FIG. The gas injection nozzle 73 shown in FIGS. 8 and 9 is similar to the gas injection nozzle 3, and the corresponding components are denoted by the same reference numerals. FIG. 9 shows the upper nozzle body 10 for convenience of illustration.
Is omitted. The difference between the gas injection nozzle 73 and the gas injection nozzle 3 is that the configuration of the pressing means for pressing the nozzle hole adjusting piece 8 against the lower nozzle main body 11 is different. That is, although the wedge piece 9 is used as the pressing means of the gas injection nozzle 3, the eccentric device 74 is used as the pressing means of the gas injection nozzle 73. In the present embodiment, since the wedge piece 9 is not used, the second side surface 34 of the fitting groove 29 of the lower nozzle main body 11 is not used.
Are formed parallel to the plate surface of the steel strip 5.

The eccentric device 74 includes an eccentric member 75 and a rotating shaft 76. The eccentric member 75 is realized by a cam, for example, and is configured such that the distance between the axis and the outer peripheral surface increases and decreases along the circumferential direction. Eccentric member 75
Are provided on the rotating shaft 76 at intervals in the axial direction, and the shapes of the plurality of eccentric members 75 are all the same. The axis of the eccentric member 75 and the axis 78 of the rotating shaft 76 are coaxial, and the outer peripheral surface of the eccentric member 75 is parallel to the axis 78. The rotation shaft 76 and the eccentric member 75 are
Side surface 53 of nozzle hole adjusting piece 8 and fitting groove 2
9 and the second side surface 34. The axis 78 of the rotating shaft 76 is parallel to the plate surface of the steel strip 5. The rotation shaft 76 is
The vicinity of both ends is supported by a side plate 79 so as to be freely angularly displaceable. One end of the rotating shaft 76 projects outward in the axial direction from the side plate 79, and a handle 77 is provided at the projecting portion. The handle 77 angularly displaces the rotation shaft 76 and the eccentric member 75. The other configuration is completely the same as the configuration of the gas injection nozzle 3.

The eccentric member 75 is operated by operating the handle 77.
Can be fixed by pressing the nozzle hole adjusting piece 8 against the lower nozzle main body 11 or can be opened. That is, as shown in FIG. 10, the handle 77 is operated to the first position 80 and the maximum eccentric surface 83 including the axis of the eccentric member 75 is operated.
If the eccentric member 75 is angularly displaced so as to be substantially parallel to the horizontal plane, a pressing force can be applied to the nozzle hole adjusting piece 8, and the nozzle hole adjusting piece 8 can be pressed against the lower nozzle body 11 and fixed. Can be. The maximum eccentric surface 83 is an imaginary surface in which the distance between the axis of the eccentric member 75 and the outer peripheral surface is maximized. Further, as shown in FIG. 11, if the handle 77 is operated to the second position 81 and the eccentric member 75 is angularly displaced so that the maximum eccentric surface 83 is substantially parallel to the plate surface of the steel strip 5. The pressure can be released, and the nozzle hole adjusting piece 8 can be easily pulled out. The first position 8
The angle between 0 and the second position 81 is 90 °.

As described above, in this embodiment, the nozzle hole adjusting piece 8 is moved to the lower nozzle body 11 by a simple handle operation.
Can be fixed or released to
The nozzle hole adjusting piece can be replaced in a short time.

[0040]

As described above, according to the first aspect of the present invention, since the nozzle hole adjusting piece is configured to be detachable, the nozzle hole can be adjusted according to the plate width of the metal strip without stopping the operation. The adjustment piece can be replaced, and the nozzle hole shape can be changed to the optimum shape. Therefore, gas wiping can always be performed with the optimum nozzle hole shape, and edge overcoat can be prevented and the distribution of the amount of adhesion in the width direction of the metal band can be made uniform.

According to the second aspect of the present invention, since the pressing means is a tapered wedge piece, it is possible to fix or open the nozzle hole adjusting piece with respect to the nozzle body by a simple operation. it can. Therefore, the nozzle hole adjusting piece can be replaced in a short time.

According to the third aspect of the present invention, the nozzle hole adjusting piece attachment / detachment guide is provided near the tip of the wedge piece, so that the nozzle hole adjusting piece can be smoothly attached / detached. it can. Therefore, the nozzle hole adjusting piece can be replaced in a shorter time.

According to the fourth aspect of the present invention, since the pressing means is an eccentric device capable of angular displacement, the nozzle hole adjusting piece can be fixed to or opened from the nozzle body by a simple angular displacement operation. can do. Therefore, the nozzle hole adjusting piece can be replaced in a short time.

According to the present invention, the nozzle body is divided into upper and lower two parts, and a metal shim is provided between the upper nozzle body and the lower nozzle body. Can be adjusted so as to have a predetermined value in the vertical direction. Further, since a metal shim that is softer than each nozzle body is provided, it is possible to prevent rattling between the upper nozzle body and the lower nozzle body after tightening.

[Brief description of the drawings]

FIG. 1 is a side view showing a simplified configuration of a gas injection nozzle of a gas injection nozzle device for plating thickness adjustment according to an embodiment of the present invention.

FIG. 2 is a plan view of the gas injection nozzle shown in FIG.

FIG. 3 is a simplified side view showing the configuration of a gas injection nozzle device for plating thickness adjustment according to an embodiment of the present invention.

FIG. 4 is a simplified perspective view showing a configuration of a lower nozzle main body 11 shown in FIG.

FIG. 5 is a perspective view showing a simplified configuration of a nozzle hole adjusting piece shown in FIG. 1;

FIG. 6 is a front view showing the shape of a nozzle hole as viewed from a plate surface of a steel strip.

FIG. 7 is a simplified perspective view showing a configuration of a wedge piece shown in FIG. 1;

FIG. 8 is a simplified side view showing a configuration of a gas injection nozzle according to another embodiment of the present invention.

9 is a plan view of the gas injection nozzle shown in FIG.

FIG. 10 is a side view showing a state where the nozzle hole adjusting piece is pressed by the eccentric member.

FIG. 11 is a side view showing a state where the pressing force on the nozzle hole adjusting piece by the eccentric member is released.

[Explanation of symbols]

 1 Gas Injection Nozzle Device for Adjusting Plating Thickness 3, 73 Gas Injection Nozzle 5 Steel Strip 6 Nozzle Hole 7 Nozzle Body 8 Nozzle Hole Adjusting Piece 9 Wedge Piece 10 Upper Nozzle Body 11 Lower Nozzle Body 26 Positioning Protrusion 29 Fitting Groove 43 Positioning Recess 63 Removable guide 68 Shim 74 Eccentric device 75 Eccentric member 76 Rotating shaft 77 Handle

Claims (5)

[Claims] 1. On the both sides of a metal strip which is conveyed almost vertically upward through a bath above a bath surface of a hot-dip metal,
In the gas injection nozzle apparatus for adjusting the plating thickness, which injects gas from the nozzle holes of a pair of gas injection nozzles provided to face each other with the metal strip interposed therebetween, and blows off excessive plating metal plated on the metal strip. A nozzle body having one of a positioning protrusion or a positioning recess and forming one inner surface of a nozzle hole extending in the width direction of the metal band; and a nozzle body having a positioning protrusion or a positioning recess of the nozzle body. A nozzle hole adjusting piece having a positioning recess or a positioning protrusion that is in contact with the nozzle body and detachably inserted into the nozzle body and forming the other inner surface of the nozzle hole;
And a pressing means for pressing the positioning convex portion or the positioning concave portion of the nozzle body. 2. The pressure means is a tapered wedge piece extending in the width direction of a metal strip, and the wedge piece is detachably inserted between a nozzle body and a nozzle hole adjustment piece. The gas injection nozzle device for plating thickness adjustment according to claim 1, wherein: 3. A base end and a distal end of the wedge piece project outward from both ends of the nozzle body in the inserted state, and a nozzle hole adjusting piece is attached to and detached from the distal end of the projected wedge piece. The gas injection nozzle device for plating thickness adjustment according to claim 2, wherein a guide table is provided. 4. The pressing means includes an eccentric member whose distance between an axis and an outer peripheral surface increases and decreases in a circumferential direction, wherein the eccentric member is provided between a nozzle body and a nozzle hole adjusting piece, and is provided around an axis. 2. The gas injection nozzle device for plating thickness adjustment according to claim 1, wherein the gas injection nozzle device is capable of angular displacement. 5. The nozzle body has an upper nozzle body having a nozzle inner surface defining an upper surface of a nozzle hole, and one of a positioning projection and a positioning recess, and is integrally fixed to the upper nozzle body. A lower nozzle main body, and a shim interposed between mutual contact surfaces of the upper nozzle main body and the lower nozzle main body and made of a metal softer than the material of each nozzle main body. 5. The gas injection nozzle device for plating thickness adjustment according to any one of 4.