KR101778457B1 - Backwarded cooling apparatus for coated strip and coating facility - Google Patents

Abstract

The present invention relates to a coated steel plate pre-cooling device, a coated steel plate post-cooling device, and a plating facility including the same, capable of improving a quality of the coated steel plate by raising a cooling speed of the steel plate coated with a plating solution. That is, the present invention comprises: a plating bath provided such that a plating solution passes through a steel plate; a coated steel plate pre-cooling device provided such that the plating solution cools the steel plate, coated on an outer surface thereof, in the plating bath; and a coated steel plate post-cooling device provided after the pre-cooling device on a movement path of the steel plate, and provided to cool again the steel plate having been cooled by the plating steel plate pre-cooling device.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plating apparatus,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plated steel plate after-cooling apparatus and a plating apparatus including the same.

In the manufacturing process of steel products, continuous plating process is performed to produce coated steel sheet according to customer's needs.

In such a continuous plating process, the molten plating liquid attached to the surface of the steel sheet passing through the plating bath provided with a plating solution such as zinc is cooled to produce a coated steel sheet.

That is, since the steel plate having passed through the plating bath has excess plating liquid adhered to both sides thereof, it is formed into a plating layer having an appropriate thickness by using an air knife, and then the unfused zinc solution of about 460 DEG C or more is cooled And a plating layer having sufficient strength is formed on the surface of the steel sheet by solidification using the apparatus, thereby producing a coated steel sheet.

However, if the cooling of the plating solution does not proceed rapidly, the sequin pattern, which is a crystal growth pattern generated on the surface of the plating layer, can not be miniaturized, thereby causing a problem in the plating quality.

On the other hand, in order to solidify the plating layer, the uncoagulated plating solution is cooled using air such as an air cooler, and the plating layer, which is partially solidified and secured to a certain degree of strength, is cooled by a cooling nozzle Respectively.

The reason why the steel plate coated with the plating solution is cooled by using the air cooler at the initial stage of cooling of the steel plate is as follows. When water droplets of the cooling water are sprayed on the coating layer in an uncoagulated state, a pit mark .

That is, at the initial stage of cooling of the plating layer, air is sprayed to cool the plating layer, thereby preventing occurrence of surface defects on the coated steel sheet.

In addition, the plated layer, which is solidified to some extent by the air cooler and secured to a certain degree of strength, is completely solidified by spraying cooling water from a cooling nozzle. In order to cool the plated layer, the cooling water is attached to the plated layer, However, since only a part of the injected cooling water adheres to the plating layer, there is a problem that the cooling ability is lowered.

As described above, the cooling method using the air at the initial stage of the solidification of the plated layer is slower than the cooling method using the cooling water, and only the cooling water is adhered to the plating layer even in the cooling method by the injection of the cooling water. There arises a problem that a sequin which is a zinc coagulation pattern of the plating layer due to low-speed cooling becomes excessively large.

That is, when the sequin pattern shown in FIG. 5 (a) is formed on the surface of the coated steel sheet, the degree of gloss and the gloss of the plated product are lowered, so that they can not be used for high quality products such as automobile exterior materials and exterior materials for home appliances.

Further, when the plating layer which has not sufficiently cooled contacts with the transfer roll, a part of the plating liquid adheres to the roll, thereby generating a pick-up mark in the longitudinal direction on the surface of the steel sheet, There is also a problem that becomes a factor.

In addition, according to the low-speed cooling of the plating layer, it is necessary to secure a sufficient cooling time of the coated steel sheet in the equipment for continuously producing the coated steel sheet, and as a result, the length of the cooling line becomes longer.

An object of the present invention is to improve the quality of a coated steel sheet by increasing the cooling rate of the coated layer applied to the steel sheet, and also to provide a plating steel post traced cooling apparatus and a plating apparatus including the same.

The plated steel plate after-cooling apparatus according to an embodiment of the present invention is provided with a trailing body unit, which is provided on a moving path of a partially coagulated steel plate, and a trailing body unit, And a charging unit provided in the trailing body unit integrally with the cooling water spraying unit, for charging the cooling water to impart polarity to the cooling water spraying unit.

In addition, the charging unit of the coated steel plate after-cooling apparatus according to an embodiment of the present invention may include an electrode portion provided in the electrode supporting portion and the electrode supporting portion provided in the trailing body unit and having an electrostatic charge applied thereto to form an electric field And at least a part of the flow path portion of the cooling water injection unit through which the cooling water flows is provided in front of the electrode portion with respect to the cooling water injection direction so as to charge the cooling water provided in the flow path portion with the same polarity .

Further, the cooling water spraying unit of the coated steel plate traverse cooling apparatus according to an embodiment of the present invention may include a trailing container unit that is provided in the trailing body unit and is grounded to the ground, to which cooling water is supplied, And a spot nozzle part for receiving cooling water from the trailing container part and spraying the cooling water to the steel plate.

Further, the spot nozzle portion of the coated steel plate after-cooling apparatus according to an embodiment of the present invention may be provided with a plurality of regions having a width larger than the width of the steel sheet.

The cooling water spraying unit of the coated steel plate after-cooling apparatus according to an embodiment of the present invention may include a pressure-providing portion communicating with the spot nozzle portion and providing air to increase the spraying pressure of the cooling water .

Further, the trailing body unit of the coated steel plate traverse cooling apparatus according to an embodiment of the present invention may include a trailing frame portion provided on a moving path of the steel plate and a peripheral portion of the spot nozzle portion, And a trailing air curtain portion leading to the steel sheet.

According to another embodiment of the present invention, there is provided a plating facility comprising a plating tank having a steel plate passed through a plating solution, a plated steel plate preceding cooling device provided to cool a steel plate coated on the outer surface of the plating solution in the plating tank, And the plating steel plate following cooling device provided downstream of the movement path of the steel plate than the cooling device and provided to cool the steel plate cooled by the plating steel plate preceding cooling device again.

The post-cooling of the coated steel sheet of the present invention and the plating facility including the same have the advantage that the quality of the coated steel sheet can be improved and the size of the equipment can be prevented by increasing the cooling rate of the coated layer.

Particularly, when the cooling water is sprayed for cooling the steel plate coated with the plating solution partially coated on the outer surface, the cooling water is jetted while being charged, so that the charging efficiency with respect to the cooling water sprayed can be enhanced, The effect of increasing the rate can be obtained.

Accordingly, the cooling efficiency due to the injection of the cooling water can be increased.

In addition, when at least a part of the flow path portion of the cooling water injection unit through which the cooling water flows is provided in front of the electrode portion of the charging unit based on the cooling water injection direction, the polarity of the charged cooling water can be sprayed with the same polarity So that it is possible to prevent the problem that the charging polarity of the cooling water is canceled in the spraying process, thereby further increasing the deposition rate of the cooling water on the plating layer.

1 is a front view showing a plating facility of the present invention.
2 is a front view showing a plated steel plate after-cooling device of the present invention.
3 is a perspective view showing a plated steel plate after-cooling apparatus according to the present invention.
Fig. 4 is a front view showing an embodiment in which the trailing body unit in the plated steel plate after-cooling apparatus of the present invention includes a trailing air curtain portion.
Fig. 5 is a photograph showing a state in which a sequin pattern is coarsened at the time of cooling the plating layer according to the prior art, and a state in which a sequin pattern is refined at the time of cooling the plating layer according to the present invention.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventive concept. Other embodiments falling within the scope of the inventive concept may readily be suggested, but are also considered to be within the scope of the present invention.

The same reference numerals are used to designate the same components in the same reference numerals in the drawings of the embodiments.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plated steel plate preceding cooling apparatus 100, a plated steel plate post cooling apparatus 200, and a plating apparatus including the same, wherein the cooling rate of the plated layer applied to the steel plate S is increased, Not only the quality can be improved, but also the size of the facility can be prevented.

5 is a front view showing a plating facility of the present invention. FIG. 5 (a) is a photograph showing a state in which a sequin pattern is coarsened when a plating layer is cooled by a conventional technique, and FIG. 5 ) Is a photograph showing a state in which a sequin pattern has become finer at the time of cooling the plating layer by the present invention.

The plating solution according to another embodiment of the present invention includes a plating tank 300 in which a steel sheet S is passed through as a plating solution L, Is provided downstream of the movement path of the steel plate (S) than the preceding cooling device, and the plated steel plate preceding cooling device (100) is provided after the plated steel plate preceding cooling device And a plated steel plate following cooling apparatus 200 provided to cool the cooled steel sheet S again.

Such a plating steel plate preceding cooling apparatus 100 and the coated steel plate following cooling apparatus 200 can improve the cooling rate for the steel sheet S coated with the plating solution L, The sequin pattern that can be formed in the solution L can be made finer.

In other words, as shown in Fig. 5 (b), as compared with the case where the cooling rate is not secured conventionally as shown in Fig. 5 (a), in the present invention, a cooling rate capable of finely dividing the sequin pattern can be secured It is.

The plated steel plate preceding cooling apparatus 100 is an apparatus for cooling the steel plate S coated with the plating solution L at an initial stage in which the steel plate S is discharged from the plating vessel 300, Cooling is performed.

The plated steel plate following cooling apparatus 200 is a device for cooling the plated layer of the partially coagulated steel sheet S cooled by the plated steel plate preceding cooling apparatus 100 to finish the cooling of the plated layer do.

To this end, the plated steel plate following cooling apparatus 200 is positioned behind the moving path of the steel plate S from the plated steel plate preceding cooling apparatus 100. That is, the steel plate S is discharged from the plating tank 300, passes through the plated steel plate preceding cooling apparatus 100 firstly, and then passes through the plated steel plate following cooling apparatus 200 secondarily .

In the case of the plating vessel 300, the plating solution L is applied to the steel sheet S. To this end, the plating tank 300 is provided with a plating solution L such as a molten zinc solution, and a pot roll 400 for guiding the movement of the steel sheet S may be provided.

An air knife 500 is provided at a position between the plating bath 300 and the plated steel plate preceding cooling apparatus 100 to adjust the thickness of the plating solution L applied to the plating bath 300 Lt; / RTI >

Particularly, since the plating-steel following cooling apparatus 200 discharges the cooling water while charging the cooling water for cooling the steel plate S on which the plating solution L coated on the outer surface is partially solidified, It is possible to increase the charging efficiency with respect to some solidified plated layers and to increase the cooling efficiency with the injection of the cooling water.

In addition, at least a part of the flow path portion 221 of the cooling water spraying unit 220 through which the cooling water flows flows toward the electrode portion 232 of the charging unit 230 based on the cooling water spraying direction, It is possible to spray the polarity of the cooling water jetted with the same polarity so that the charging polarity of the cooling water is canceled out during the jetting process to prevent the cooling water from adhering to the plating layer .

FIG. 2 is a front view showing a plating-steel following cooling apparatus 200 according to the present invention. Referring to FIG. 2, the plating-steel following cooling apparatus 200 according to an embodiment of the present invention includes a plating solution L A trailing body unit 210 provided on a moving path of a partly solidified steel plate S and a cooling water spraying unit provided in the trailing body unit 210 for spraying cooling water to the steel plate S by air pressure, And a charging unit 230 provided in the trailing body unit 210 integrally with the cooling water injection unit 220 and charging the cooling water to impart polarity to the cooling water.

As described above, the coated steel plate after-cooling apparatus 200 of the present invention is provided with the charging unit 230 integrally with the cooling water injection unit 220 through which the cooling water is injected, so that the cooling water can be injected after the polarity is imparted.

Accordingly, since the charging efficiency of the cooling water can be increased, the deposition rate of the cooling water on the plating layer on the steel sheet S can be increased and the cooling efficiency can be increased.

Here, the trailing body unit 210 serves as a body provided with the cooling water injection unit 220 and the charging unit 230, and the plating solution L may be a part of the steel sheet S coated with the plated layer And is provided on the movement path.

The trailing body unit 210 may include a trailing frame portion 211 and a trailing air curtain portion 212 to control the jetting area of the cooling water jetted from the cooling water jetting unit 220, A detailed description will be given later with reference to Fig.

The cooling water spray unit 220 serves to spray the cooling water to the steel plate S. To this end, the cooling water spray unit 220 includes a flow path portion 221, a trailing container portion 222, (223), and an air pressure providing unit (224).

Particularly, the passage portion 221 serves to transfer the cooling water to be sprayed from the trailing container portion 222 to the spot nozzle portion 223. At this time, a part of the flow passage portion 221 is connected to the charging unit 230, the cooling water to be injected can be charged and jetted to the same electrode. A detailed description thereof will be described later.

The trailing container portion 222 is provided with cooling water to be sprayed, and may be connected to a supply pipe for receiving cooling water W from the outside, and some of the stored cooling water may be discharged through a drain pipe. However, most of the stored cooling water is transferred to the spot nozzle part 223 through the flow path part 221 and sprayed to the steel plate S.

Here, the trailing container portion 222 is grounded at the ground, and is constituted by the material of the conductor, so that it can perform a function of receiving a negative charge at the ground or discharging a negative charge at the time of charging the cooling water .

In particular, since the cooling water in the trailing container portion 222 is charged with the same polarity by the electrode portion 232 to be described later, it is possible to prevent the problem that the charging polarity is canceled in the middle of the injection of the cooling water.

The spot nozzle unit 223 serves to spray the cooling water transferred from the trailing container unit 222 through the flow path unit 221 to the steel plate S. [

Here, the spot nozzle unit 223 may include a hole having a shape in which the injection path of the cooling water to be injected is gradually reduced, thereby increasing the injection speed of the cooling water to be injected.

In addition, the spot nozzle unit 223 may be provided as a spray nozzle capable of widening the spray area of the cooling water to be sprayed.

As described above, the cooling water spraying unit 220 of the coated steel plate after-cooling apparatus 200 according to an embodiment of the present invention is provided in the trailing body unit 210 and is grounded to the ground, And a spot nozzle unit 223 connected to the container unit 222 and the flow path unit 221 to receive the cooling water from the trailing container unit 222 and to spray the cooling water to the steel plate S .

In addition, a plurality of the spot nozzles 223 may correspond to the width of the steel sheet S, and a detailed description thereof will be given later with reference to FIG.

The pressure providing unit is provided to increase the spraying power of the cooling water transferred from the trailing container unit 222 to the spot nozzle unit 223 through the flow path unit 221.

In other words, the cooling water may be sprayed from the spot nozzle unit 223 only by the spraying force caused by the flow of the cooling water, but the air pressure providing unit 224 may further be provided to further increase the spraying power of the cooling water.

In other words, the cooling water injection unit 220 of the plated steel plate following cooling apparatus 200 according to an embodiment of the present invention is connected to the spot nozzle unit 223, (224) for providing the air pressure (A).

The air pressure providing unit 224 may be configured to receive the air A from the outside through the piping and to supply the received air A to the spot nozzle unit 223, (A) flow path that communicates with the outlet (223) can be formed.

The charging unit 230 is configured to be injected in a charged state so that the cooling water can have a polarity.

To this end, the charging unit 230 is provided integrally with the cooling water injection unit 220 and is provided in the trailing body unit 210.

Particularly, the charging unit 230 is positioned behind the part of the flow path 221 of the cooling water injection unit 220 in the direction of spraying the cooling water, so that the cooling water to be sprayed can be formed in the same polarity and sprayed. A detailed description thereof will be described later.

The charging unit 230 of the coated steel plate after-cooling apparatus 200 according to the embodiment of the present invention is provided in the electrode supporting portion 231 and the electrode supporting portion 231 of the trailing body unit 210 And at least a part of the flow path portion 221 of the cooling water injection unit 220 through which the cooling water flows is connected to the electrode And the cooling water provided in the flow path portion 221 is charged in the same polarity.

In other words, the flow path unit 221 serves to transfer the cooling water to be sprayed from the trailing container unit 222 to the spot nozzle unit 223. At this time, the charging unit 230 is connected to the flow path unit 221 So that the cooling water to be injected can be injected by being charged by the same electrode.

That is, by charging the cooling water at a polarity opposite to that of the polarity of the electrode unit 232, the entire cooling water can be charged and discharged with the same polarity.

The electrode support part 231 serves to support the electrode part 232 so as to be integrally formed with the cooling water injection unit 220.

The electrode support part 231 may be provided in the trailing body unit 210 provided with the cooling water injection unit 220 and may include the electrode part 232 therein.

The high voltage generator PS is grounded to the ground and the electrode unit 232 is connected to the high voltage generator PS for applying external static electricity to the static electricity generator. The electrode unit 232 can maintain a state where a positive charge is applied to the positive electrode (+) or the negative electrode (-) by applying a high voltage in a state where the positive electrode (232) is connected.

For example, in order to apply the electrode unit 232 to the positive electrode of the positive electrode (+), the high voltage generator PS discharges the negative charge existing in the electrode unit 232 through the ground.

When the electrode part 232 is applied to the positive electrode of the positive electrode (+), the cooling water provided in the flow part 221 adjacent to the electrode part 232 is charged to the negative (-), The cooling water is increased in adhesion force to be adhered to the steel sheet, thereby enhancing the cooling ability.

Here, the cooling water is charged because the trailing container portion 222 connected to the flow path portion 221 is grounded and receives a negative charge from the ground and transfers the negative charge to the cooling water, .

3 is a perspective view illustrating a coated steel plate post-cooling apparatus 200 according to the present invention. Referring to FIG. 3, the spot nozzle unit 223 of the coated steel plate post-cooling apparatus 200 according to an embodiment of the present invention, And a plurality of steel plates (S) having a width greater than the width of the steel sheet (S) are provided.

This is for uniformly cooling the steel sheet S. In other words, in order to form a uniform cooling effect by spraying the charged cooling water on the whole width of the steel strip S, a plurality of spot nozzle portions 223 are provided in the width direction of the steel strip S Respectively.

4 is a front view showing an embodiment in which the trailing body unit 210 includes a trailing air curtain part 212 in the coated steel plate after-cooling apparatus 200 of the present invention. Referring to FIG. 4, The trailing body unit 210 of the plated steel plate traverse cooling apparatus 200 according to the present invention is provided on the trailing frame portion 211 provided on the moving path of the steel sheet S and in the peripheral portion of the spot nozzle portion 223 And a trailing air curtain part 212 for guiding the cooling water to the steel sheet S, as shown in FIG.

The trailing body 210 includes the trailing air curtain 212 so as to control the injection area of the cooling water injected from the cooling water injection unit 220.

In other words, when the cooling water is sprayed from the spot nozzle unit 223, the following air curtain unit 212 shields the vicinity of the cooling water jetted by the air A to spray the cooling water, You can do it.

For this purpose, the trailing air curtain part 212 may be provided in connection with a pipe for receiving the air A from the outside.

100: Plated steel plate preceding cooling system 200: Plated steel plate post cooling system
210: trailing body unit 211: trailing frame part
212: a trailing air curtain section 220: a cooling water spraying unit
221: channel portion 222: trailing container portion
223: Spot nozzle unit 224: Air pressure supply unit
230: charging unit 231:
232: electrode part 300: plating bath
400: Port roll 500: Air knife

Claims (7)

A trailing body unit provided on a moving path of a partially solidified steel plate plating solution coated on the outer surface;
A cooling water injection unit provided in the trailing body unit and configured to inject cooling water into the steel plate by air pressure; And
A charging unit provided in the trailing body unit integrally with the cooling water injection unit, for charging the cooling water to impart polarity to the cooling water;
/ RTI >
The cooling water jetting unit includes:
A trailing container unit provided in the trailing body unit and grounded on the ground and provided with cooling water;
A spot nozzle unit that receives cooling water from the trailing container unit and ejects the cooling water to the steel plate; And
A channel portion provided between the trailing container portion and the spot nozzle portion for transmitting the cooling water from the trailing container portion to the spot nozzle portion;
Lt; / RTI >
The charging unit includes:
An electrode supporter provided in the trailing body unit; And
An electrode unit provided on the electrode support unit and forming an electric field by applying a static charge;
/ RTI >
Wherein at least a part of the flow path portion is provided in front of the electrode portion with respect to the cooling water spraying direction so that electric charges having the same polarity as the electrode portion existing in the cooling water are discharged to the ground through the trailing container portion, Wherein the entire cooling water is charged to an opposite polarity to that of the static electricity applied to the electrode unit and is transmitted to the spot nozzle unit. delete delete The method according to claim 1,
Wherein the spot nozzle portion is provided with a plurality of regions each having a width larger than the width of the steel plate. The method according to claim 1,
The cooling water jetting unit includes:
An air pressure providing unit communicating with the spot nozzle unit and providing air to increase an injection pressure of the cooling water;
Wherein the cooling device is a cooling device. The method according to claim 1,
Wherein the trailing body unit comprises:
A trailing frame portion provided on the movement path of the steel plate; And
A trailing air curtain provided at a periphery of the spot nozzle unit and guiding the cooling water to the steel plate;
Wherein the cooling device is a cooling device. A plating tank through which a steel sheet passes through a plating solution;
A plated steel plate preceding cooling device provided in the plating bath to cool a steel plate coated on the outer surface of the plating solution; And
The plating apparatus according to any one of claims 1 and 4 to 6, which is provided after the path of movement of the steel sheet ahead of the preceding cooling apparatus and is provided to cool the steel sheet cooled by the preceding steel sheet cooling apparatus, Cooling device;
≪ / RTI >

Images