JP2012140693A - Baffle plate for gas wiping device and gas wiping method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the yield of a splash by forming a baffle plate or a body of the baffle plate with SiN, and to uniform a plating mass of deposit per unit area to both sides of a steel strip.SOLUTION: The baffle plate for a gas wiping device and a gas wiping method are characterized as follows. The baffle plate is used by the gas wiping device (1) to regulate the mass of deposit per unit area of a plating liquid which adheres to both sides of a plated steel strip (5) which runs up through a plating tank (4), wherein a body (20) of the baffle plate is formed with SiN.

Description

  The present invention relates to a baffle plate for a gas wiping apparatus and a gas wiping method, and in particular, by forming a baffle plate body from Si3N4, the amount of splash is suppressed and the amount of plating adhered to both surfaces of a steel strip is made uniform. Regarding new improvements.

As a conventional gas wiping device, for example, the device configuration disclosed in Patent Document 1 can be disclosed as a schematic diagram in FIG.
That is, what is denoted by reference numeral 1 in FIG. 8 is a gas wiping device, and the first and second wiping nozzles 2 and 3 disposed opposite to each other are disposed apart from each other. .

  A plating tank 4 is disposed at a lower position of the gas wiping device 1, and a plated steel strip 5 that continuously travels upward through the plating tank 4 has plating 6 attached to both surfaces thereof. In this configuration, the amount of deposition of the plating 6 is controlled by the amount of gas ejected from the wiping nozzles 2 and 3.

In the case described above, the width of each wiping nozzle is generally wider than the plated steel strip width W (FIG. 9), and gas is ejected from the entire width.
When the configuration of FIG. 8 is shown in plan, it is as shown in FIG. 9, and positions A and B deviated from both end portions 5 a and 5 b of the plated steel strip 5 in the plated steel strip width direction Wa of the plated steel strip 5. As shown by the arrow G, a jet collision of the wiping gas occurs.

Since the jets at the positions A and B in FIG. 9 described above become a slightly outward collision turbulent flow, the molten metal of the plating on the both ends 5a and 5b is peeled off from the both ends 5a and 5b of the plated steel strip 5. Since the surface of the molten metal that has been scattered is oxidized by the atmospheric gas or partially solidified by cooling, the quality of the plated steel strip 5 deteriorates. It was a factor.
The generation amount increases as the passing speed of the plated steel strip 5 increases, and increases as the pressure of the wiping gas increases.
In addition, a larger noise was generated in the impinging jet, and the surrounding environment was very bad at the site of the plating process.

In order to overcome the above-described problems of the conventional configuration, for example, the configuration of the schematic diagram of FIG. 11 disclosed in Patent Document 2 can be given.
That is, first and second baffle plates 10 and 11 are provided outside the both ends 5a and 5b of the plated steel strip 5 so as to be flush with the plated steel strip 5; The collision of the wiping gas jet was prevented by the baffle plates 10 and 11, and the jet state of the wiping gas outside the plated steel strip 5 could be brought close to the jet state of the wiping gas in the plated steel strip 5.

JP 60-82652 A JP-A-1-208441

Since the conventional baffle plate for a gas wiping apparatus is configured as described above, the following problems exist.
That is, as shown in FIG. 12, when the plated steel strip 5 and the baffle plate 11 are brought close to each other, the effect of preventing the collision of the wiping gas jets from the wiping nozzles 2 and 3 is increased. As shown in FIG. 12, the splash due to the collision jet between the plated steel strip 5 and the baffle plate 11 may adhere to the baffle plate 11 as the fixed metal 12 and may be fixed as it is.

When the state of the fixed metal 12 made of the above-described molten metal fixed by the splash proceeds, a large turbulent flow component C (FIG. 12) is generated in the wiping gas jet, and the wiping nozzles 2 and 3 are melted by plating. Zinc scatters and adheres, and the wiping gas pressure partially decreases, resulting in variations in the plating adhesion of the plated steel strip 5 and partial overcoat of hot dip plating.
Further, in order to prevent the splash from adhering to the baffle plates 10 and 11, the baffle plate 11 may be separated from the plated steel strip 5, but as described above, the amount of splash generated increases. It was a conflicting issue. Moreover, although the proposal which uses the said baffle plate 11 as a general ceramic is provided, since the wettability was good, the subject similar to the above-mentioned occurred.

  The baffle plate for a gas wiping apparatus according to the present invention is a baffle plate used in a gas wiping apparatus for adjusting the amount of plating solution adhering to both surfaces of a plating steel strip that continuously travels upward through a plating tank. In the gas wiping apparatus baffle plate, the baffle plate main body is formed of Si3N4, the baffle plate main body is mounted on a metal plate, and the metal plate is The connection part for connecting the baffle plate main body, and a holding groove part for holding the baffle plate main body provided integrally or separately on one side of the metal plate, and the connection The portion includes a plurality of longitudinal connection plates or a single connection plate, and each of the longitudinal connection plates or the single connection plate and the bolt. The metal plate and the baffle plate main body are connected to each other, and the front end of the holding groove has a bent groove that bends along the shape of the outer bent portion of the baffle plate main body. A straight part on one side of the plate main body and an outer bent part following the straight part are inserted into the bent groove part, and the metal plate is made of stainless steel. 6. A method using the baffle plate for a gas wiping device according to any one of 6 above.

Since the baffle plate for a gas wiping apparatus and the gas wiping method using the same according to the present invention are configured as described above, the following effects can be obtained.
That is, in the baffle plate for a gas wiping device comprising a baffle plate main body used in a gas wiping device for adjusting the amount of plating solution adhered to both surfaces of the plating steel strip that continuously travels upward through the plating tank, Since the baffle plate body is made of Si3N4, the wettability is low, and the metal adhesion of the molten metal due to splash is greatly reduced compared to general ceramics. The surrounding wiping gas pressure and the baffle plate itself Since the molten metal falls due to the vibration due to the vibration, the splash can be reduced without affecting the quality of the hot-dip steel strip.
Further, since the baffle plate main body is attached to the metal plate, the entire body does not need to be made of expensive Si3N4, the cost is reduced, the strength is improved, and the attachment to the apparatus is facilitated.
The metal plate includes a connection portion for connecting the baffle plate main body, and a holding groove portion for holding the baffle plate main body provided integrally or separately on one side of the metal plate. Thus, the baffle plate main body can be inserted and engaged with the holding groove portion of the metal plate, so that the metal plate and the baffle plate main body can be easily and reliably held and connected.
Further, the connection portion is composed of a plurality of longitudinal connection plates or one connection plate, and the metal plate and the baffle plate body are connected by the respective longitudinal connection plates or one connection plate and a bolt, In the unlikely event of replacement, it is easy to replace the baffle plate body.
Moreover, the front-end | tip part of the said holding groove part has the bending groove part bent along the shape of the outer side bending part of the said baffle plate main body, and the outer side bending part which follows the linear part of the one side of the said baffle plate main body, and the said linear part Can be used as a durable baffle plate by preventing damage due to the impact of Si3N4 which is easily damaged.
Moreover, the said metal plate can use the baffle plate excellent in durability by comprising stainless steel.
By using the baffle plate for a gas wiping device according to any one of claims 1 to 6, stable gas wiping with less splash can be performed.

It is a top view of the principal part of the baffle plate for gas wiping apparatuses by this invention. It is a side view which shows the principal part of FIG. It is a top view of the other form of the baffle plate of FIG. It is a top view which shows the other form of FIG. It is a top view which shows the baffle plate main body of FIG. It is a side view which shows the principal part of FIG. It is a top view which shows the metal plate of FIG. It is a front view which shows the conventional wiping nozzle apparatus. It is a top view of FIG. It is a perspective block diagram of the principal part of FIG. It is the conventional structure which provided the baffle plate in the structure of FIG. FIG. 12 is an enlarged plan view showing a state in which a fixed metal is attached to a baffle plate in the conventional configuration of FIG.

  It is an object of the present invention to provide a baffle plate for a gas wiping apparatus and a gas wiping method in which a baffle plate is formed of Si3N4 to suppress the generation of splash and make a plating adhesion amount uniform. .

Hereinafter, preferred embodiments of a baffle plate for a gas wiping apparatus and a gas wiping method according to the present invention will be described with reference to the drawings.
Note that the same or equivalent parts as those in the conventional example are described with the same reference numerals, and the conventional configurations of FIGS. 10 and 11 are also incorporated in the configuration of the present invention.
1 is a gas wiping device, and a gap between a pair of wiping nozzles 2 and 3 which are provided in the gas wiping device 1 and which are opposed to each other and separated is passed through the plating tank 4 of FIG. The plated steel strip 5 is configured to pass continuously, and the wiping gases 2a and 3a from the wiping nozzles 2 and 3 are sprayed onto the plated steel strip 5, whereby the plated steel strip 5 In this configuration, the amount of plating attached to 5, that is, the thickness is adjusted to be constant.

A pair of baffle plates 10 and 11 are provided at both ends 5a and 5b (shown in FIG. 11) of the plated steel strip 5 of the gas wiping apparatus 1, but one baffle plate is omitted in FIG. Only 11 is shown.
The baffle plate 11 may be composed of only the baffle plate main body 20. However, since the baffle plate main body 20 is formed of Si3N4, the baffle plate main body 20 may be damaged by an impact as compared with a metal plate. As shown in FIG. 3, the baffle plate main body 20 made of Si3N4 is located on the plated steel strip 5 side via a connection plate 22 that forms a connection portion 22 </ b> A with a metal plate 21 made of stainless steel or the like as a receiver for the baffle plate main body 20. Are connected by bolts 23. That is, the metal plate 21 is used as a reinforcing material for the baffle plate body 20 so that the impact resistance is increased.

The metal plate 21 is provided with the connection plate 22 for connecting the baffle plate main body 20 and a holding groove portion 24 for holding the baffle plate main body 20 provided integrally or separately on one side of the metal plate 21. The holding groove portion 24 is formed in a straight line at a tip portion 25 formed in an L shape of the metal plate 21.
The holding groove portion 24 is formed in a straight line shape, and the baffle plate body 20 is formed in a substantially rectangular shape combined with a straight line portion.

In the other form of the baffle plate 11 shown in FIGS. 4 to 7 shown in FIGS. 4 to 7, a straight portion 30 and an outer bent portion 31 continuous to the straight portion 30 are formed on one side of the baffle plate main body 20. .
A bent groove portion 32 is formed on the one end portion 25 side of the metal plate 21 so as to be continuous with the linear holding groove portion 24.

The baffle plate main body 20 has the linear portion 30 inserted into the holding groove portion 24 and fitted therein, and the outer bent portion 31 is inserted into and fitted into the bent groove portion 32, whereby the baffle plate main body 20 is inserted. 20 is connected to the metal plate 21 to form the baffle plate 11.
Further, the baffle plate main body 20 and the metal plate 21 are connected to each other through bolts 37 in which a plurality of longitudinal connection plates 35 as connecting portions 22A provided on the metal plate 21 are provided in the mounting holes 36 of the baffle plate main body 20. By being attached to the baffle plate body 20, they are firmly connected to each other.
Note that the position displayed as the nozzle height H in FIG. 4 indicates the nozzle position for injecting the wiping gas from each of the wiping nozzles 2 and 3 in FIG.
FIG. 7 shows a case where the baffle plate body 20 is removed from the metal plate 21 and the baffle plate body 20 is replaced with a new one or before attachment.

As described above, the baffle plate main body 20 is a ceramic plate made of a fine ceramic made of silicon nitride (Si3N4), and has superior thermal shock resistance and chemical resistance compared to general ceramics, and has a thermal expansion. The rate is low and the strength is high up to a high temperature, and it has sufficient wettability with respect to the plating solution in the plating tank 4.
Therefore, it can withstand a rapid temperature change of about 400 to 700 degrees when the metal adheres, and since the difference in thermal expansion coefficient from the metal is large, the interface between the metal (hot dip plating solution) and Si3N4 is easy. The metal adhesion becomes smaller when the baffle plate body 20 of Ai3N4 is used after surface polishing so that the part where the sintered structure of Si3N4 is dense becomes the surface.

  The baffle plate for a gas wiping apparatus and the gas wiping method according to the present invention are not limited to plating adhesion control to a plated steel strip, but can be applied to a production line for food, medicine, and the like.

DESCRIPTION OF SYMBOLS 1 Gas wiping apparatus 2 Wiping nozzle 2a Wiping gas 3 Wiping nozzle 3a Wiping gas 4 Plating tank 5 Plating steel strip 6 Plating 11 Baffle plate 20 Baffle plate main body 21 Metal plate 22 Connection plate 22A Connection portion 24 Holding groove portion 25 Tip portion 30 Straight portion 31 Outer bending portion 32 Bending groove portion 35 Longitudinal connection plate 36 Mounting hole 37 Bolt

Claims (7)

The baffle plate body (20) used in the gas wiping device (1) for adjusting the amount of plating solution adhering to both sides of the plating steel strip (5) that travels continuously upward through the plating tank (4) In the baffle plate for a gas wiping apparatus consisting of
The baffle plate for a gas wiping apparatus, wherein the baffle plate body (20) is made of Si3N4.   The baffle plate for a gas wiping apparatus according to claim 1, wherein the baffle plate body (20) is attached to a metal plate (21).   The metal plate (21) is provided integrally or separately on one side of the metal plate (21) and a connecting portion (22A) for connecting the baffle plate main body (20), and the baffle plate main body (20 3. A baffle plate for a gas wiping apparatus according to claim 2, further comprising: a holding groove portion (24) for holding a gas wiping device.   The connection portion (22A) is composed of a plurality of longitudinal connection plates (35) or one connection plate (22), and each of the longitudinal connection plates (35) or one connection plate (22) and a bolt (23). The baffle plate for a gas wiping apparatus according to claim 3, wherein the metal plate (21) and the baffle plate main body (20) are connected to each other.   The front end portion (25) of the holding groove portion (24) has a bent groove portion (32) bent along the shape of the outer bent portion (31) of the baffle plate main body (20), and the baffle plate main body (20 The gas according to claim 3 or 4, characterized in that a linear portion (30) on one side and an outer bent portion (31) following the straight portion (30) are inserted into the bent groove portion (32). Baffle plate for wiping equipment.   The baffle plate for a gas wiping apparatus according to any one of claims 2 to 5, wherein the metal plate (21) is made of stainless steel.   A gas wiping method using the baffle plate for a gas wiping apparatus according to any one of claims 1 to 6.

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