JPH01275772A - Method for improving cooling capacity in adjusting plating amount in continuous plating on metallic sheet - Google Patents

Abstract

PURPOSE:To easily adjust the plating amt. by forcibly passing a cooling gas on the surface of a plating metal at the time of bringing the plating metal into contact with a moving heated metallic sheet, melting the metal and depositing a plating film. CONSTITUTION:A band steel 1 is heated in a heating furnace to a temp. higher than the m.p. of of zinc, and continuously traveled in direction of the arrow. A zinc plating material 2 preheated by an IR heater is drawn out orthogonally to the band steel 1, and brought into contact with the band steel 1. Consequently, a zinc plating film 2a is deposited on the band steel 1, and uniformized by a surface regulator. At this time, the material 2 is surrounded with a box 3 contg. a passage 4 for circulating cooling gaseous N2, before the material 2 is brought into contact with the band steel 1. Flow-controlled cooling gaseous N2 is passed through the passage 4 in direction of the arrow to control the cooling of the material 2, and the plating amt. is easily adjusted in a short time.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a vJ4 adjustment method for the amount of plating applied when continuously plating the surface of a metal plate, and is particularly aimed at improving cooling performance. It is something to do.

[Conventional technology]

Conventionally, the hot-dip plating method, which has been widely used to form a plating film on the surface of copper strips, has many problems in terms of the quality and type of plating, and many efforts have been made to solve these problems. Improvement plans have been proposed and implemented, but no fundamental decisions have been reached in terms of workability, productivity, safety, cost, etc.

Therefore, the present inventors have proposed a new continuous plating method that is completely different from the conventional hot-dip plating method. Figure 3 schematically shows the principle of this plating method, in which moving metal plates αIK plated metal material (1) are brought into contact and a molten layer (2υ) of plated metal is formed at the contact point. By continuously supplying the plated metal material to the metal plate IQ, the molten plated metal is continuously deposited as a plating film on the surface of the moving metal plate α1. be.

[Problem that the invention seeks to solve]

On the other hand, with the diversification of product types and performance, a wide variety of products are produced in small quantities, and as a link to this, the plating applied to these products is often required to have different performance, thickness, etc. . For example, in the case of automobile outer panels, there may be differences in the required plating thickness depending on the area of use, such as the body part and the area around the legs. However, if one were to use the above method to coat materials with different plating thicknesses in one line, a new problem would arise that would be difficult to solve.

The thickness H of the plating film (a) formed by the above method is:
If the moving speed of the metal plate α1 is U, the supply speed of the plated metal material is V, and the thickness of the plated metal material (A) in the direction of movement of the metal plate is W, it is given by ■ H=W (d). .

Among these, when the moving speed U of the metal plate (1 (I) and the thickness W of the plated metal material (A) are approximately constant, the plating film (2z
The thickness I (is proportional to the supply rate V of the plated metal material C21, but this supply rate V also changes depending on the dissolution rate of the plated metal material (A). The formation of the molten metal layer C!υ is
The plated metal material (1G) is heated in advance with a heating device such as an infrared heater, and then melted by the sensible heat of the metal plate at the contact point, so the melting rate of the plated metal material depends on the sensible heat of the metal plate at the point of contact. As a result, the supply rate V depends on the preheating ability of the metal plate 0I and the mated metal material (2).

Here, if we try to change the plating thickness during line operation according to the above request, it will be necessary to adjust the heating capacity of the metal plate αl and the plated metal material (to) in accordance with the target plating amount. When the amount of adhesion decreases, it is normal to temporarily stop heating and allow cooling to reduce the heating capacity, and a very high cooling response cannot be expected.

Therefore, when changing the amount of plating when the amount of plating is decreased, there is a problem that a portion (unsteady portion) where the amount of plating cannot be instantaneously adjusted to the target plating amount is produced, resulting in poor yield.

The present invention was devised in view of the above-mentioned problems, and provides a new method in which the amount of plating deposited can be easily and quickly adjusted.
1. It enables you to perform to your maximum potential.

[Means for solving problems]

Therefore, the present invention enables a cooling gas to be forced to flow on the surface of a metal plate and/or a plated metal material, and determines whether or not this gas flow layer is formed and the gas flow rate when the gas flow layer is formed. The cooling control of the metal plate and/or the plated metal material is performed by adjusting the .

[For production]

With the above-described configuration, the cooling response when adjusting the plating adhesion is increased, thereby making it possible to change the amount of plating adhesion in a short time. Regarding heating, there are various heating methods with high response (for example, methods of irradiating with a high-energy body such as laser light), and by using these methods in combination, the amount of plating deposited can be changed efficiently.

〔Example〕

The implementation of the present invention will be explained below based on the accompanying drawings.

Figure 1 shows the equipment for carrying out coupled single-sided galvanizing according to the method of the present invention, (1) is a copper strip made of four gold plates, t2]
It is a galvanized metal material.

The copper strip (1) flows continuously in the direction of the arrow while being heated to a temperature above the melting point of zinc in a heating furnace (not shown), while the galvanized material (2) is heated in a heating furnace (not shown) to a temperature higher than the melting point of zinc.
After being preheated in a box (not shown), the copper strip (1) is passed through a box (3) to be described later and fed out from a direction perpendicular to the surface of the copper strip (1).
It is in contact with this copper strip (1). Through this contact, the galvanized material (2) is heated above the melting point of zinc mainly by the sensible heat of the copper strip (1), and a molten zinc layer is formed there.

Therefore, a galvanized film (2a) is attached to the surface of the copper strip. Thereafter, the plating film (2a) is leveled by a surface conditioning device (not shown) having an ultrasonic vibrator or the like, thereby performing surface conditioning.

In this example, after the galvanized material (2) passes through the infrared heater and just before reaching the point of contact with the copper strip (1), the galvanized material (2) is placed in a box having a gas circulation path (4) inside. It is surrounded by the body (3) and continuously supplied.

This box body (3) has a hollow part in the center that allows the galvanized material (2) to pass through, and inside the box body (3) there is a ring-shaped partition wall (3) that surrounds the galvanized material (2).
a) is provided, and a gas circulation path (4) is formed;
When cooling N2 gas is passed through it, it circulates in the direction shown by the arrow. The circulating N2 gas is near the point of contact with the galvanized material (
2) is first cooled, and then cooled while rising along the surface of the galvanized material (2). Therefore, if N2 gas is poured into the gas circulation path (4)K as required, the galvanized material (2) can be sufficiently cooled before reaching the contact point. Note that a portion of the N2 gas will be extracted from the through hole (3b) at the bottom of the box (3).

Using the apparatus jt as described above, an experiment was conducted to reduce the amount of zinc plating deposited. As shown in Figure 2, in order to reduce the amount of galvanized coating from 80 f/- to 409 f/2, if the preheating of the galvanized material (2) is stopped and the process is allowed to cool (conventional method), it takes K30. On the other hand, in this example equipment, when N-gas was flowed through the gas circulation path (4) at an average flow rate of about 3 m/s, the amount of adhesion could be reduced to the target amount in about 15 minutes, and the effect was It became clear that the value was extremely high. Also, the steel strip (1) may be cooled instead of the galvanized material (2).In this example, single-sided plating is shown, but double-sided plating is also possible, and also in the line direction. Although the horizontal case is shown, it is possible to perform the flow in other than the horizontal direction, and in the case of the vertical direction, the flow can be carried out either up or down.

〔Effect of the invention〕

As detailed above, according to the method for improving cooling performance in total deposition adjustment according to the present invention, the cooling response is higher than before, and when it is desired to reduce the amount of plating deposited, changes can be made in a short time. This makes it possible to easily control plating deposition.

[Brief explanation of the drawing]

Figure 1 is an enlarged sectional view of the main parts showing an example of equipment for implementing the method of the present invention, Figure 2 is a graph showing the time reduction effect obtained by this equipment, and Figure 3 is a continuous flow diagram proposed by the inventors. FIG. 2 is an explanatory diagram schematically showing the principle of a plating method. In the figure, (1) is a copper strip, (2) is a galvanized material, (2a) is a galvanized film, (3) is a box, (4) is a gas circulation path,
〔〔 is metal plate, metal material with metal plate, eu is molten layer, (
2) Each of the plating films is shown. Figure 1 Figure 1 Figure 3

Claims (1)

[Claims] A plating metal material is brought into contact with a moving metal plate, a molten layer of the plating metal is formed at the contact point, and the plating metal material is continuously supplied to the metal plate, thereby melting the plated metal material. For continuous plating of metal plates, in which the plated metal is continuously deposited as a plating film on the surface of the moving metal plate, cooling gas can be forced to flow over the surface of the metal plate and/or the plated metal material. , a method of continuous plating of metal plates characterized in that the cooling of the metal plate and/or the plated metal material is controlled by adjusting the presence or absence of the formation of this gas flow layer and the gas flow rate when the gas flow layer is formed. A method for improving cooling capacity in adjusting the amount of adhesion.