JP2000096299A - Electrode device in electrical treating vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the damage of protectors by metallic strip edges, etc., with an electrode device to be disposed in an electrical treating vessel for electrical treatment of the metallic strip. SOLUTION: The electrode device has insoluble electrodes which face a metallic strip bus line in the electrical treating vessel and are arranged at prescribed spacings from a metallic strip bus line and the insulative protectors projectingly disposed apart suitable spacings on the surfaces of the insoluble electrodes facing the metallic strip bus line. The protectors are composed of insulating materials of >=80 HSD in Shore hardness (the Shore hardness regulated by JIS Z 2264). The occurrence of the large shorting trouble and the surface appearance defects and surface defects of the strip by the damage of the protectors may be surely prevented and since there is no damage of the protectors, the service life of the insoluble electrodes may be prolonged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode device provided in an energization processing tank for performing an energization process such as electroplating, electrolytic polishing, electrolytic cleaning, etc. on a metal strip.

[0002]

2. Description of the Related Art In a current supply process of a metal strip such as electroplating, electrolytic polishing, and electrolytic cleaning, for example, a metal strip to be passed through is placed in parallel with the cathode in an electrolytic solution in a current supply tank. An electrode is used as an anode, and an electrochemical reaction is caused between the anode and the cathode. In such an energization treatment, it is important to optimize a distance between both electrodes (interelectrode distance) in terms of reaction efficiency. That is, if the distance between the electrodes is large, the electrolyte resistance increases and the reaction efficiency decreases,
In principle, it is desirable that the distance between the poles is as small as possible.

[0003] However, in particular, when the energization processing tank is a horizontal processing tank for performing energization processing by moving a metal strip in the horizontal direction, the metal strip may flap in the vertical direction due to fluctuations in the tension of the metal strip, shape defects, and the like. As a result, there is a problem that the metal strip easily contacts the electrode. Therefore, in consideration of the flapping of the metal strip, the distance between the poles in the steady operation state has to be set wider.

To solve such a problem, Japanese Patent Publication No. Sho 50-8
No. 020 proposes a horizontal electroplating tank having a structure in which an insoluble anode is used as an electrode and a protector for preventing short circuit is provided on a surface of the insoluble anode opposite to the strip pass line. 4 and 5 show this conventional horizontal electroplating tank. FIG. 4 is a longitudinal sectional view of the plating tank, FIG. 5 is a plan view of the inside of the plating tank, 4 is an insoluble electrode, and 5 is a protector. , 6 is a conductor roll,
7 is a plating solution inlet, 8 is a plating solution receiving tank, and 9 is a plating solution outlet.

[0005] The metal strip S is guided in the horizontal direction by the conductor roll 6, enters the plating tank, and is plated. Although a separate tank body may be provided as a plating tank,
In this example, the plating bath is constituted by the insoluble electrodes 4 provided vertically above and below the metal strip S, and the outside is lined with an insulator such as rubber or synthetic resin as required. Into the plating bath, a plating solution is introduced from a plating solution inlet 7 and flows between the insoluble electrodes 4 in a direction opposite to the metal strip advancing direction, and a plating solution outlet 9 from a lower plating solution receiving tank 8.
Spilled out and collected.

The surface of the insoluble electrode 4 facing the metal strip pass line is made of an insulating material such as bakelite so that the metal strip S and the insoluble electrode 4 are not short-circuited due to fluctuations in tension of the metal strip and other factors. The protector 5 is attached. The protector 5 is a rectangular member having a rectangular cross section. In this structural example, the protector 5 is used to make the plating solution flow in the plating tank uniform and to prevent uneven plating in the width direction of the metal strip S. Are arranged in a C shape in the direction of the pass line.

[0007] Regarding the protector for preventing short circuit provided on such an insoluble electrode, besides the above-mentioned publications, for example, JP-A-7-150396 and JP-A-61-124.
599, JP-A-7-11489, JP-A-7-11
Various shapes are proposed in, for example, Japanese Patent Application Laid-Open No. 11488, Japanese Utility Model Application Laid-Open No. 4-25864, and the like.

Incidentally, the above-mentioned protector needs to be electrically insulative.
No. 488, the material is FR
Synthetic resins such as P, bakelite, and high-molecular polyethylene are employed. On the other hand, in recent years, the distance between the metal strip and the electrode tends to be shortened, and setting the distance to about 9 to 15 mm is becoming common.
For this reason, contact between the metal strip and the protector is unavoidable due to poor shape such as middle elongation, ear waves, and warpage of the metal strip, meandering and flapping of the metal strip in the electric treatment tank.

[0009]

However, such contact between the metal strip and the protector causes a problem that the protector is damaged by the metal strip edge. In particular, in the case of the protector material generally used in the related art, a situation occurs in which the metal strip edge bites into the protector, thereby causing the following serious problem. That is, as shown in FIG. 6A, when the edge of the metal strip S bites into the protector 5, the metal strip S continuously contacts the insoluble electrode 4, causing a large short circuit. A hole in the insoluble electrode occurs.

Further, the metal strip S once bitten
6B, the sagging down portion 50 of the damaged protector portion remains even after the edge of the protector 5 comes off the protector 5. As shown in FIG. 7, such a dripping portion 50 obstructs the flow of the plating solution flowing between the metal strip and the insoluble electrode and makes the plating solution flow non-uniform. As a result, Japanese Patent Application Laid-Open No. 7-150396 discloses As shown in the figure, the surface appearance of the manufactured plated steel sheet causes poor appearance,
Causes quality problems. In addition, as shown in FIG. 6C, when the sagging portion 50 due to the damage of the protector 5 is particularly remarkable, the sagging portion 50 comes into contact with the metal strip S and causes surface defects such as scratches and dents on the strip surface. .

Accordingly, an object of the present invention is to solve the problems of the prior art and to provide an electrode device capable of appropriately preventing damage to a protector due to a metal strip edge or the like.

[0012]

The present inventors have conducted various experiments in order to provide an electrode device in which damage to the protector as described above is suppressed as much as possible. As a result, the protector has a Shore hardness (defined by JIS Z2264). Shore hardness)
Found that using an insulating material of 80 HSD or more can effectively prevent damage to the protector due to metal strip edges and the like.

The present invention has been made on the basis of such knowledge, and is characterized by an electrode device provided in an electric treatment tank for energizing a metal strip, wherein the electrode device is provided with a metal strip pass line in the tank. An insoluble electrode opposed to the metal strip pass line and disposed at a predetermined distance from the metal strip pass line; and an insulative protector projecting from the surface of the insoluble electrode facing the metal strip pass line at an appropriate interval. Wherein the protector is made of an insulating material having a Shore hardness (Shore hardness specified in JIS Z 2264) of 80 HSD or more.

[0014]

1 and 2 show an embodiment of a horizontal energization processing tank provided with an electrode device according to the present invention. In the figure, S is a metal strip that passes horizontally continuously through the electric treatment tank, and 1 is an insoluble electrode (lower electrode) that is disposed at a predetermined distance below and facing the pass line of the metal strip S at a predetermined distance. Although not shown, an insoluble electrode (upper electrode) is arranged above the strip pass line symmetrically with the lower electrode with the strip pass line interposed therebetween.

In the gap a between the insoluble electrode 1 and the metal strip pass line, a jet nozzle 3 arranged downstream of the metal strip in the direction of travel of the metal strip is supplied with a plating solution or the like toward the upstream side of the direction of travel of the metal strip. The electrolyte is allowed to flow. An insulating protector 2 is protruded from the surface of the insoluble electrode 1 facing the strip pass line at an appropriate interval. Although there is no particular limitation on the shape of the protector 2, the protector 2 is usually formed of, for example, a rectangular member having a rectangular cross section. The protector 2 has a configuration in which the metal strip S having a shape defect or a sheet passing defect has an insoluble electrode 1.
Acts to prevent direct contact with

In the electrode device having the above configuration, in the present invention, the protector 2 is provided with a Shore hardness (JIS Z 226).
(Shore hardness specified in 4) is 80 HSD or more, preferably 150 HSD or more. As such an insulating material, synthetic resins such as plastics are used. Among them, high-molecular polyethylene, polyethylene terephthalate, and the like are particularly preferable. Further, among these materials, since hardness differs depending on physical properties, those having a Shore hardness of 80 HSD or more are selected and used.

Table 1 shows that an insoluble electrode 1 was used in an electroplating tank provided with an electrode device having a structure as shown in FIGS.
In the case where plating was performed using various insulating materials having different Shore hardnesses as protector 2 of Example 2, the results of investigating the presence or absence of electrode damage, the appearance of the plated surface of the manufactured metal strip, and the occurrence of surface defects are shown. . FIG. 3 shows the results of an investigation on the relationship between the Shore hardness of the protector 2 and the life of the insoluble electrode 1 in a similar electroplating tank.

According to Table 1, by setting the Shore hardness of the protector to 80 HSD or more, the protector is hardly damaged by the metal strip, so that the degree of damage to the electrode itself is reduced, and the excellent plating surface appearance and It can be seen that a plated steel sheet having no surface defects can be manufactured. Also,
According to FIG. 3, the Shore hardness of protector 2 is 80 HSD.
It is shown that since the above-described arrangement causes almost no damage to the protector, the life of the insoluble electrode 1 can be extended.

[0019]

[Table 1]

Although there is no particular upper limit for the Shore hardness of the protector, since the material and manufacturing costs increase with the increase in hardness, the upper limit of the Shore hardness is 250 from the viewpoint of economic efficiency.
It is preferable to be about HSD.

In the embodiment shown in FIG. 1, the protector 2
Are provided along the width direction of the metal strip S, but the arrangement form is arbitrary. For example, as shown in FIG. 5, they may be arranged in a C shape toward the pass line direction. The electrode device of the present invention can be applied to various kinds of energization processing tanks for performing energization processing such as electropolishing and electrolytic cleaning, in addition to electroplating tanks for electroplating metal strips.

[0022]

As described above, according to the electrode device of the present invention, damage to the protector due to contact with the metal strip edge or the like can be properly prevented. The occurrence of defects and surface defects (scratch flaws, press flaws) can be reliably prevented. Further, since there is no damage to the protector, the life of the insoluble electrode can be extended.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of an electrode device of the present invention with an upper electrode omitted.

FIG. 2 is a side view showing an embodiment of the electrode device according to the present invention with an upper electrode omitted;

FIG. 3 is a graph showing the influence of the Shore hardness of a protector constituting an electrode device on the life of an insoluble electrode.

FIG. 4 is a longitudinal sectional view showing an example of a conventional horizontal electroplating tank.

FIG. 5 is a plan view showing the inside of the electroplating tank shown in FIG. 4;

FIG. 6 is an explanatory diagram showing a damaged state of a protector in a conventional electrode device.

FIG. 7 is an explanatory view showing a damaged state of a protector in a conventional electrode device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Insoluble electrode, 2 ... Protector, 3 ... Jet nozzle, a
… Gap

Claims (1)

[Claims] 1. An electrode device provided in an energization processing tank for energizing a metal strip, wherein the electrode device faces a metal strip pass line in the tank and has a predetermined interval between the metal strip pass line and the metal strip pass line. In an electrode device having an insoluble electrode to be disposed and an insulative protector protruding from a surface of the insoluble electrode facing a metal strip pass line at an appropriate interval, the protector may have a Shore hardness (JIS Z 2264). Characterized in that the electrode device is formed of an insulating material having a Shore hardness of 80 HSD or more.