KR20230149072A - Hot-dip galvanizing equipment with automatic scraper - Google Patents

Abstract

The present invention relates to a hot-dip galvanizing apparatus equipped with an automatic scraper, and more specifically, to a furnace filled with a plating solution; A sink roll installed in the furnace; A stabilizing roll installed in the furnace and supporting the steel plate that has passed through the sink roll; Arms supporting both ends of each of the sink roll and the stabilizing roll; And in order to form a foreign matter layer made of foreign matter with a thickness of 0.05 to 0.1 mm on the surfaces of each of the sink roll and the stabilizing roll, the ends of the blades are spaced 0.05 to 0.1 mm apart from the surfaces of each of the sink roll and the stabilizing roll. It is characterized in that it includes; a scraper portion installed to be maintained as a spaced apart sieve and movable parallel to the axis of the roll.

Description

Hot-dip galvanizing equipment with automatic scraper}

The present invention is a melting machine equipped with an automatic scraper that increases the grip of the surface of the roll against the steel sheet being transported and prevents the roll from slipping on the surface of the steel sheet and causing damage such as scratches to the plating layer formed on the surface of the steel sheet. It concerns galvanizing equipment.

Coated steel sheets (strips) have superior corrosion resistance and appearance compared to steel sheets, so they are used in various technological fields such as home appliances, office equipment, and automobiles. In particular, hot-dip galvanized steel sheet is a plated steel sheet in which a zinc layer is formed on the surface by dipping the steel sheet in zinc melted at about 450℃. The adhesion of zinc is excellent, making it easy to bond to the surface of home appliances, etc., and it is used to paint the surface. In this case, the adhesion of the coating film is good and the corrosion resistance after painting is excellent, making it highly usable.

A conventional hot-dip galvanizing device consists of a furnace filled with a hot-dip galvanizing solution, a sink roll, a stabilizing roll, a collecting roll, and an arm welded to both ends of each roll, and a long steel sheet (strip) supplied from outside the furnace. ) changes its transport direction upward along the circumference of the sink roll, and then maintains tension as it passes between the stabilizing roll and the collecting roll.

However, as the hot-dip galvanizing operation continues for a long time, impurities formed by mixing the molten zinc solution contained in the furnace, aluminum, and various other additives necessary for plating adhere to rolls such as sink rolls, forming an alloy layer on the surface of the roll, These alloy layers gradually accumulate to form a thick layer, and if part of the alloy layer is broken, the marks are transferred to the surface of the plated steel sheet and cause product defects, so a scraper is needed to remove the alloy layer on the roll surface.

For example, in Korea Public Utility Model No. 20-2011-0003832 (April 20, 2011), the first scraper 110 is brought into contact with the surface of the sink roll 10, and the first scraper 110 is applied to the surface of the stabilizing roll 20. 2 The technical feature is to remove foreign substances (alloy layer) adhered to the surfaces of each sink roll (10) and stabilizing roll (20) by contacting the scraper (210).

However, in the case of the prior art as described above, the grip force between the surface of the sink roll, stabilizing roll, etc. from which the foreign material layer has been removed by the scraper and the steel plate is weakened, so the roll often cannot rotate in accordance with the feed speed of the steel plate and slips on the surface of the steel plate. This causes damage such as scratches to the plating layer formed on the surface of the steel sheet, resulting in a problem that significantly deteriorates the quality of the plated steel sheet product.

1. Korean Patent Publication No. 2014-0066856 (June 3, 2014) 2. Korea Public Utility Model No. 2011-0003832 (2011. 04. 20.)

The present invention is intended to solve the above problems, and is intended to improve the contact force between the surface of the roll and the steel sheet being transported to prevent a discrepancy between the transport speed of the steel sheet and the rotational speed of the rotating roll due to contact friction with the steel sheet being transported. The purpose is to provide a hot-dip galvanizing device equipped with a sufficient automatic scraper.

The problem to be solved by the present invention is not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art from the following description. will be.

The present invention, derived to solve the above problems, relates to a hot-dip galvanizing device equipped with an automatic scraper, and more specifically, to a furnace filled with a plating solution; A sink roll installed in the furnace; A stabilizing roll installed in the furnace and supporting the steel plate that has passed through the sink roll; Arms supporting both ends of each of the sink roll and the stabilizing roll; And in order to form a foreign matter layer made of foreign matter with a thickness of 0.05 to 0.1 mm on the surfaces of each of the sink roll and the stabilizing roll, the ends of the blades are spaced 0.05 to 0.1 mm apart from the surfaces of each of the sink roll and the stabilizing roll. It is characterized in that it includes; a scraper portion installed to be maintained as a spaced apart sieve and movable parallel to the axis of the roll.

According to the hot-dip galvanizing device equipped with an automatic scraper according to the present invention, sufficient contact force can be obtained between the surface of the roll and the steel sheet being transported, so that the rotating roll is controlled by the transport speed of the steel sheet and contact friction with the steel sheet being transported. It has the effect of preventing discrepancies between rotational speeds from occurring, which causes the roll to fail to rotate in accordance with the feed speed of the steel sheet and slip on the surface of the steel sheet, causing damage such as scratches to the plating layer formed on the surface of the steel sheet. can be prevented.

Figure 1 shows a front view of a hot-dip galvanizing apparatus equipped with an automatic scraper according to an example of the present invention.
Figure 2 shows a side view of a hot-dip galvanizing apparatus equipped with an automatic scraper according to an example of the present invention.
Figure 3 is a photograph taken of a state in which the surface of the foreign material layer created on the surface of the roll is not uniform and part of the foreign material layer is damaged.

Since the present invention can be modified in various ways and can have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all transformations, equivalents, and substitutes included in the spirit and technical scope of the present invention. In describing the present invention, if it is determined that a detailed description of related known technologies may obscure the gist of the present invention, the detailed description will be omitted.

The terms used in this application are only used to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Terms such as first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

The present invention relates to a hot-dip galvanizing apparatus equipped with an automatic scraper, and more specifically, to a furnace filled with a plating solution; A sink roll installed in the furnace; A stabilizing roll installed in the furnace and supporting the steel plate that has passed through the sink roll; Arms supporting both ends of each of the sink roll and the stabilizing roll; And in order to form a foreign matter layer made of foreign matter with a thickness of 0.05 to 0.1 mm on the surfaces of each of the sink roll and the stabilizing roll, the ends of the blades are spaced 0.05 to 0.1 mm apart from the surfaces of each of the sink roll and the stabilizing roll. It is characterized in that it includes; a scraper portion installed to be maintained as a spaced apart sieve and movable parallel to the axis of the roll.

In the present invention, the furnace is filled with a plating solution, and the plating solution is a liquid metal for plating the surface of a steel sheet, and may be, for example, a zinc molten solution.

In the present invention, the sink roll is installed in the furnace, and serves to change the direction of movement of the steel plate along the surface so that the steel plate entering the furnace can change direction and exit upward. The sink roll is generally designed to have a larger diameter than the stabilizing roll to prevent the steel plate from bending excessively.

In the present invention, the stabilizing roll is installed in the furnace, supports the steel sheet that has passed through the sink roll, and serves to allow the steel sheet that has passed through the sink roll to rise vertically without bending.

In the present invention, the arm supports both ends of each of the sink roll and the stabilizing roll, and the arm supports both ends of each of the sink roll and the stabilizing roll, allowing each roll to rotate in contact with the steel plate. . One arm may support a plurality of rolls, and each arm may support one sink roll and one stabilizing roll. However, in order to be able to set the arrangement between the plurality of rolls more freely, a roll may be installed on each arm. It is desirable that these are supported one by one.

In the present invention, the scraper part is movable parallel to the axis of the roll, and is used to form a foreign material layer of 0.05 to 0.1 mm thick foreign material on the surface of each of the sink roll and stabilizing roll. It is characterized in that the ends of the blades are installed to be maintained at intervals of 0.05 to 0.1 mm from the surface of each of the easing rolls. The present invention, unlike the existing hot-dip galvanizing equipment equipped with a scraper, forms a foreign material layer made of foreign material with a thickness of 0.05 to 0.1 mm on the surface of each of the sink roll and stabilizing roll, thereby forming a surface of the roll on which the foreign material layer is formed. Since it is possible to have sufficient grip force between the steel plate and the steel plate being transported, it is possible to prevent a discrepancy between the conveying speed of the steel plate and the rotational speed of the rotating roll due to contact friction with the steel plate being transported. This prevents the roll from occurring between the steel plate and the steel plate being transported. This prevents damage such as scratches to the plating layer formed on the surface of the steel sheet due to failure to rotate in accordance with the transfer speed and slipping on the surface of the steel sheet. If the gap between the surface of each of the sink roll and the stabilizing roll and the end of the blade of the scraper is less than 0.05 mm, the thickness of the foreign material layer formed on the surface of the roll is too thin or almost so that the grip force for the steel sheet being transported is sufficient. This causes the roll to slip on the steel plate, causing product defects. If the gap between the surface of each of the sink roll and stabilizing roll and the end of the blade of the scraper exceeds 0.1 mm, the roll This phenomenon of slipping on the steel plate can be prevented, but the thickness of the foreign material layer formed on the surface of the roll is too thick, so the overall surface is not uniform, and even some of the foreign material layer is easily damaged, such as dents, leaving marks on the damaged area. This is because there is a problem that it is transferred to the surface of the plating layer and increases the defect rate of the product.

In the present invention, the scraper unit includes a blade for scraping off a foreign material layer of alloy components formed on a roll, a support arm supporting the blade, a buffer portion coupled to one end of the support arm, and a buffer portion engaged with the buffer portion so that the buffer portion is horizontal. It is characterized by including a horizontal moving member so that it can be moved. In order to provide a suspension effect when in contact with the foreign material layer of the roll rotating on the blade, the buffer part has a space formed inside, a support arm is coupled to the lower part, and the shock absorber is provided with a space applied by an air cylinder or hydraulic cylinder. A housing that can be moved up and down by pressure; and a spring portion provided vertically in the inner space of the housing and capable of adjusting the elastic force by tightening and loosening the nut. In particular, the spring unit includes a rod having one end coupled to the upper surface of the internal space of the housing and equipped with a nut to enable loosening and tightening of the nut. A fixing part coupled to the other end of the rod and fixed to the outside of the housing so that its position is fixed regardless of the vertical movement of the housing; and a spring into which the rod is inserted and provided between the nut and the fixing part.

The scraper part is a sieve in which the end of the blade is in contact with the foreign material layer of the alloy component formed on the surface of the roll. As the roll rotates, the blade of the scraper part is pushed in the rotation direction of the roll, so that when the plating device is operated for a long time, there is a gap between the roll and the blade of the scraper part. Since the gap widens and the scraper unit cannot remove the foreign material layer accumulated on the surface of the roll, in this case, pressure by an air cylinder or hydraulic cylinder is applied to the scraper unit to prevent the blade of the scraper unit from being pushed. However, the existing scraper unit has a problem in that when pressure is applied by an air cylinder or hydraulic cylinder, the blade of the scraper unit adheres too strongly to the foreign material layer on the surface of the roll, thereby impeding the rotation of the roll. However, the scraper unit according to the present invention It is characterized by including a buffer part, so that even if pressure from an air cylinder or hydraulic cylinder is added to the scraper part, the pressure applied by the blade to the foreign material layer formed on the surface of the roll is almost canceled by the buffer part, so the rotation of the roll is prevented. At the same time, it allows the thin layer of foreign matter formed evenly on the surface of the roll to be maintained for a long time. In other words, thin film control of the foreign material layer of alloy components formed on the surface of the roll becomes possible. To be more specific, when pressure from an air cylinder or hydraulic cylinder is added to the housing of the buffer part of the scraper part, the pressure is transmitted downward to the support arm and blade, but an elastic force is applied upward from the spring provided in the internal space of the buffer part. This occurs and lifts the housing upward, thereby canceling out the pressure transmitted to the blade of the scraper unit. When the amount of pressure applied to the housing by the air cylinder or hydraulic cylinder increases, the spring is compressed by tightening the nut provided in the spring part of the buffer unit, and the stronger elastic force of the spring lifts the housing of the scraper unit upward. , This makes it possible to offset the pressure applied by the blade to the foreign material layer formed on the surface of the roll to an appropriate level.

In addition, in the scraper unit according to the present invention, even if some lumpy and protruding portions of the foreign material layer of the alloy component formed on the surface of the roll pass the blade of the scraper unit due to the rotation of the roll, the scraper unit according to the present invention is able to Because the protruding area is not removed suddenly at once, but is removed flexibly over several times, it is possible to prevent damage such as denting of part of the foreign matter layer on the surface of the roll, and this allows all foreign matter layer on the surface of the roll to be removed. You can prevent situations where you have to remove or replace the roll itself.

The foreign matter layer is formed by accumulating on the surface of the roll as zinc, aluminum, and various other additives in the molten metal are mixed. The present invention finely forms the foreign matter layer on the surface of the roll, thereby connecting the steel sheet to the surface of the roll. It is characterized by increasing the surface contact force between the plates to prevent the roll from slipping on the steel plate, and keeping the feed speed of the steel plate and the rotation speed of the roll the same. However, once the foreign material layer is formed on the surface of the roll, the growth rate of the foreign material layer becomes faster, and if the foreign material layer is formed thickly on the surface of the roll, damage to some of the foreign material layer is likely to occur, and when this happens, marks on the damaged area are likely to occur. There is a problem in that this is transferred to the surface of the plated steel sheet, causing defects in the product. In other words, in the present invention, it is very important to continuously maintain a thin layer of foreign matter of an appropriate thickness formed on the surface of the roll immersed in the molten metal, and this can be seen as being directly related to the service life of the roll.

In the present invention, the scraper unit is designed to quickly and accurately automatically measure the fine gap between the surface of the roll and the end of the blade, so that the surface and blade of each of the sink roll and stabilizing roll are removed before the start of the process. It may be desirable to include a gap detection unit that detects the size of the gap between the ends. The shock detection unit can be any device that can directly or indirectly measure the size of the gap between the surface of each of the sink roll and stabilizing roll and the end of the blade, but it can be used to increase the precision and accuracy of the measurement. In order to quickly measure the gap, it is preferable to use the laser irradiation method. The gap detection unit of the laser irradiation method is a first laser measurement unit that irradiates a laser to measure the distance to the surface of each of the sink roll and the stabilizing roll, and separately irradiates a laser to measure the distance to the end of the blade. Using the distance value to the surface of each of the sink roll and stabilizing roll measured by the second laser measuring unit and the first laser measuring unit, and the distance value to the end of the blade measured by the second laser measuring unit Thus, it may be configured to include a gap calculation module unit that calculates the size of the gap between the surface of each of the sink roll and the stabilizing roll and the end of the blade.

Hereinafter, the present invention will be described through embodiments shown in the drawings. The embodiments shown in the drawings below are merely examples to aid understanding of the present invention, and are not intended to limit the scope of the present invention.

Figure 1 is a front view of a hot-dip galvanizing apparatus equipped with an automatic scraper according to an example of the present invention, and Figure 2 is a side cross-sectional view of a hot-dip galvanizing apparatus equipped with an automatic scraper according to an example of the present invention and a buffer portion. It shows an enlarged side cross-sectional view.

According to FIGS. 1 and 2, a hot-dip galvanizing apparatus equipped with an automatic scraper according to an example of the present invention includes a furnace 100 filled with a plating solution, a sink roll 200 installed in the furnace 100, and the sink roll ( 200) and a stabilizing roll 300 that supports the steel plate (strip) that has passed through the sink roll 200, and both ends of the sink roll 200 and the stabilizing roll 300, respectively. The ends of the blades 510 are installed on the surfaces of each of the supporting arm 400 and the sink roll 200 and stabilizing roll 300 to be spaced apart at a predetermined interval and are parallel to the axes of the rolls 200 and 300. It is configured to include a scraper portion 500 that can be easily moved. A thin layer of foreign matter 600 is formed on the surfaces of the sink roll 200 and the stabilizing roll 300.

In addition, according to FIG. 1, the scraper unit 500 includes a blade 510 for removing the foreign material layer formed on the rolls 200 and 300, a support arm 520 supporting the blade 510, and the support arm ( It is configured to include a buffer unit 530 coupled to one end of the buffer unit 520 and a horizontal moving member 540 engaged with the buffer unit 530 to enable the buffer unit 530 to move horizontally. The buffer unit 530, for example, has a space formed inside, a support arm 520 is coupled to the lower part, a housing that can move up and down by pressure applied by an air cylinder at the top, and an internal space of the housing. It is provided vertically and includes a spring part whose elastic force can be adjusted by tightening and loosening the nut, wherein one end of the spring part is coupled to the upper surface of the inner space of the housing, and a nut is provided to loosen and tighten the nut. A possible rod, a fixing part coupled to the other end of the rod, fixed to the outside of the housing and fixed in position regardless of the vertical movement of the housing, and a spring into which the rod is inserted and provided between the nut and the fixing part. It may consist of: When downward pressure is applied to the housing by the air cylinder, the elastic force of the spring of the spring unit provided in the internal space of the housing acts upward to lift the housing upward, thereby causing the air cylinder to The pressure applied to the housing is offset.

Experiment example

1. Roll traction test

For a hot-dip galvanizing device equipped with an automatic scraper, the frictional force of the roll and the resulting product defect rate (%) were tested by varying the spacing between the sink roll, stabilizing roll, and the end of the blade of the scraper part. The above experiment was conducted by operating the hot-dip galvanizing equipment for 5 minutes to produce galvanized steel sheets. During the operating time, the number of times the sink roll and stabilizing roll slipped on the galvanized steel sheets and the total number of galvanized steel sheets produced were measured. The product defect rate was evaluated by calculating the ratio of the defective plated steel product area to the product area, and the results were shown in Table 1 below.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 separation distance
(mm) 0.03 0.04 0.05 0.08 0.1 0.15 0.2 roll of
slide
Number of Occurrences
(th)
7
3
0
0
0
0
0 product
defect rate
(%)
5
2
0
0
0
3
5

As can be seen from Table 1, when the spacing between the sink roll, stabilizing roll, and the end of the blade of the scraper portion is 0.05 to 0.1 mm (Examples 3 to 5), slippage of the roll does not occur at all. It is possible to achieve sufficient surface grip of the roll and at the same time minimize the defect rate (%) of the final plated steel product. In the case of Examples 1 and 2 where the gap between the sink roll, stabilizing roll, and the end of the blade of the scraper part is less than 0.05 mm, the roll slips on the plated steel plate, which causes product defects. In addition, as the spacing became narrower, the thickness of the alloy layer was too thin or almost so, the number of times the roll slipped increased, and the defect rate of the product also increased accordingly. In addition, in the case of Examples 6 and 7 in which the spacing between the sink roll, stabilizing roll, and the end of the blade of the scraper part exceeded 0.1 mm, the slipping phenomenon of the roll did not occur due to the foreign material layer, but Figure 3 As can be seen, the foreign material layer created on the surface of the roll was too thick, so the surface was not uniform, and some damage to the foreign material layer was confirmed. As a result, marks of the damaged foreign material layer were transferred to the surface of the plating layer of the plated steel sheet. It was confirmed that the defect rate of the product increased.

As described above, a person skilled in the art to which the present invention pertains will understand that the present invention can be implemented in other specific forms without changing its technical idea or essential features. The scope of the present invention is indicated by the claims to be described later rather than the detailed description above, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts are interpreted to be included in the scope of the present invention. It has to be.

100: furnace 110: plating solution
200: Sink roll 300: Stabilizing roll
400: arm 500: scraper part
510: blade 520: support arm
530: buffer part 540: horizontal moving member
550: Air cylinder 600: Foreign matter layer

Claims (4)

A furnace filled with plating liquid;
A sink roll installed in the furnace;
A stabilizing roll installed in the furnace and supporting the steel plate that has passed through the sink roll;
Arms supporting both ends of each of the sink roll and the stabilizing roll; and
In order to form a foreign matter layer consisting of foreign substances with a thickness of 0.05 to 0.1 mm on the surfaces of each of the sink roll and stabilizing roll, the ends of the blades are spaced at intervals of 0.05 to 0.1 mm from the surfaces of each of the sink roll and stabilizing roll. A hot-dip galvanizing device with an automatic scraper including a scraper portion installed to be maintained as a spaced screen and movable parallel to the axis of the roll.
According to clause 1,
A hot-dip galvanizing device with an automatic scraper, characterized in that the scraper unit is equipped with a gap detection unit that detects the size of the gap between the surface of each of the sink roll and the stabilizing roll and the end of the blade before the start of the process. .
According to clause 2,
A hot-dip galvanizing device equipped with an automatic scraper, wherein the gap detection unit uses a laser irradiation method.
According to clause 3,
The gap detection unit includes a first laser measuring unit that measures the distance to the surface of each of the sink roll and stabilizing roll by irradiating a laser; a second laser measuring unit that measures the distance to the end of the blade by irradiating a laser; And using the distance value to the surface of each of the sink roll and stabilizing roll measured by the first laser measuring unit and the distance value to the end of the blade measured by the second laser measuring unit, the sink roll and A hot-dip galvanizing device with an automatic scraper, comprising a gap calculation module unit that calculates the size of the gap between the surface of each stabilizing roll and the end of the blade.