JPH08158093A - Horizontal continuous electrolytic device provided with edge mask - Google Patents

Abstract

PURPOSE: To form a uniform plating layer on the entire surface of a steel strip when the steel strip traveling in a plating soln. is used as a cathode and a current is applied between the cathode and anodes vertically arranged to plate the strip by alternately arranging the L-shaped edge mask and the inverted L-shaped one on the edges of the strip on both sides. CONSTITUTION: Plural plating tanks 1 each provided with a plating soln. feed pipe 6 and a plating soln. outlet 7 and consisting of upper and lower box-type tanks 1A and 1B contg. an anode 2 are arranged, a current is applied between a steel strip 3 to be plated as the cathode and the anode 2 by a conductor roll 4, the strip is traveled in direction of the arrow, and the strip 3 is plated. In this case, the current is concentrated on the edge of the strip 3 on both sides, and a thicker plating is formed on the edges than the central part of the strip 3. Accordingly, an L-shaped edge mask 9 and an inverted L-shaped one 9 are alternately provided on both sides of the strip 3 in the continuous plural plating tanks 1, the plating current is not concentrated on the edges of the strip 3 on both sides, and a plating layer uniform in thickness in the width direction of the strip 3 is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an electrogalvanizing line for steel sheets (EGL), an electrotin plating line (ETL),
The current concentration on the edge part of the metal strip to be treated is reduced in various continuous electrolytic treatment equipment including electroplating equipment in each line such as tin-free line (TFL), and excessive electrolysis treatment on the edge portion is prevented. The present invention relates to a horizontal continuous electrolytic treatment apparatus equipped with an edge mask capable of performing the above.

[0002]

2. Description of the Related Art A typical example of a horizontal type continuous electrolytic treatment apparatus equipped with an edge mask is electroplating, and there are also electric cleaning, electrochemical treatment, etc. Here, steel strip (hereinafter referred to as steel sheet) is used. The case of continuously electroplating will be described. The horizontal continuous electroplating apparatus is, as shown in FIGS. 15 to 17, an electroplating tank formed by upper and lower box-shaped tanks 1A and 1B (hereinafter referred to as a plating tank).
1. A steel plate 3 was installed in an inlet side and an outlet side of an electrode 2 while running a steel plate 3 in a plating solution 10 filled between electrodes (anodes) 2 horizontally arranged with a space vertically between the electrodes 2. Power is supplied from the conductor roll 4 to perform the plating process.

The plating solution 10 is jetted from the downstream side of the plating tank 1 between the electrode 2 and the steel plate 3 by using the plating solution supply pipe 6, is made to flow in the opposite direction to the steel plate 3, and is discharged from the discharge port 7 on the upstream side. The discharged plating solution 10 enters the receiving tank 8. When plating is performed by energizing the steel plate 3 from the electrodes 2 arranged above and below in the plating tank 1 through the plating solution 10, the plating may be performed with the steel plate 3 sandwiched between the wide upper and lower electrodes 2. ,
The plating current concentrates on both side edge portions of the steel sheet 3 and the amount of the deposited coating becomes excessive, and the edge portion becomes thicker than other portions, resulting in a so-called overcoat.

In order to prevent the edge overcoat, both side edges of the steel plate 3 which passes the plating solution 10 in the plating tank 1 are illustrated.
As shown in 17, the U-shaped edge mask 9A made of a poor electrical conductor is wrapped around the edge mask 9A so that the edge mask 9
This lap margin is adjusted by advancing and retracting A in the plate width direction of the steel plate 3. It is known that by cutting off the plating current from the electrode 2 in this way, the amount of adhesion of plating at the edge portion is reduced and the steel sheet 3 is uniformly plated over the entire width direction. Incidentally, as shown in FIG. 18, a dogleg-shaped edge mask 9B may be used instead of the U-shaped edge mask 9A (see Japanese Patent Laid-Open No. 52-130435).

In addition, Japanese Patent Publication No. 62-12318 discloses that FIG.
21. As shown in FIG. 21, when the steel plate 3 is plated, the L-shaped edge mask 9C is inserted from the lower side or the upper side of the steel plate 3 into both side edge portions in proximity to each other, and It is disclosed that one of the surfaces is open. In the drawing, L is attached to the lower surface of both side edges of the steel plate 3.
The figure shows a case where a character-shaped edge mask 9C is inserted in proximity to open the upper surface.

[0006]

As described above, the conventional edge mask for preventing the edge overcoat has a U-shape as shown in FIG. 17 or a V-shape as shown in FIG. In general, the edge overcoat has been prevented by pushing a predetermined amount inward from the end of the steel plate. Further, only in the case of single-sided electroplating, an edge mask 9C having an L-shaped cross section is installed so as to mask either the upper or lower surface of the steel plate as shown in FIG. It has been used by pushing it in a predetermined amount.

However, since the U-shaped edge mask 9A or the V-shaped edge mask 9B is used by wrapping the vicinity of the steel plate edge with a gap from above and below, when the steel plate is warped or vibrates. In addition, there is a high possibility that the steel plate comes into contact with the edge mask and the steel plate is scratched or the edge mask is scraped. Further, in recent years, the distance between the steel plate and the electrode tends to be shortened (currently 9
The main shape is ~ 15mm), but both the U-shaped edge mask and the V-shaped edge mask are difficult to thin due to workability.
Further, if the distance between the steel plate and the electrode is shortened, the mask portion must be thinned, so that the strength is reduced and the life is shortened. Further, as shown in FIG. 19, when the L-shaped edge mask 9C is installed so as to mask one of the upper and lower surfaces of the steel plate and plating is performed, edge overcoat can be prevented in the case of single-sided plating. Obviously, in the case of double-sided plating, the overcoat on the non-mask surface cannot be prevented.

The present invention solves the above-mentioned problems of the prior art,
A horizontal continuous electrolytic treatment apparatus equipped with an edge mask that reduces current concentration on the edge of the steel sheet and has a high strength and can be processed into a thin shape without impeding the sheet passage of the steel sheet during electrolytic treatment. It is intended to be provided.

[0009]

In order to achieve the above-mentioned object, the present invention according to claim 1 fills a space between electrodes arranged vertically at intervals in each tank of a continuous electrolytic treatment tank. In a horizontal continuous electrolytic treatment apparatus for performing electrolytic treatment by arranging edge masks on both side edges of a metal strip to be processed which runs in an electrolytic solution, current concentration on both side edges of the metal strip to be treated is prevented. The shape of the edge mask for this purpose is L-shaped, the edge mask is inverted L-shaped and is installed so as to mask both edge portions of the upper surface of the strip, and the L-shaped electrolytic treatment tank is installed on both sides of the lower surface of the strip. It is a horizontal continuous electrolytic treatment apparatus having an edge mask, which is arranged on a treatment line in combination with an electrolytic treatment tank installed so as to mask the edge portion.

According to a second aspect of the present invention, an electrolytic treatment tank is provided in which an edge mask is formed in an inverted L shape so as to mask both side edge portions of the strip upper surface, and an L-shaped electrolytic treatment tank is formed in both side edge portions of the strip lower surface. The horizontal continuous electrolytic treatment apparatus provided with the edge mask according to claim 1, wherein the same number of electrolytic treatment tanks that are installed so as to mask are arranged on the treatment line.

According to a third aspect of the present invention, an electrolytic treatment tank is provided in which an edge mask is formed in an inverted L shape so as to mask both side edge portions of the strip upper surface, and an L-shaped electrolytic treatment tank is formed on both side edge portions of the strip lower surface. The horizontal continuous electrolytic treatment apparatus having an edge mask according to claim 1 or 2, wherein electrolytic treatment baths installed so as to mask the are alternately arranged on the treatment line.

[0012]

According to the present invention, the shape of the edge mask for preventing current concentration on both side edge portions of the metal strip to be processed is L-shaped, and the edge mask is inverted L-shaped so that both edge portions on the upper surface of the strip. Is placed on the processing line in combination with the electrolytic treatment tank installed so as to mask and the electrolytic treatment tank which is L-shaped and installed so as to mask both side edge portions of the lower surface.

Therefore, it is possible to reduce current concentration on both side edge portions of the upper surface and the lower surface of the metal strip and prevent excessive electrolytic treatment of the edge portion. In this case, by arranging the same number of electrolytic treatment tanks provided with the edge masks installed in the inverted L shape and electrolytic treatment tanks equipped with the edge masks installed in the L shape on the electrolytic treatment line, It is possible to equally reduce the concentration of the current on both side edge portions on the upper surface and the lower surface of the strip.

Further, by alternately arranging an electrolytic treatment tank having an edge mask installed in an inverted L-shape and an electrolytic treatment tank having an edge mask installed in an L-shape, a current to both side edges of the metal strip is obtained. The concentration can be reduced evenly between the upper surface and the lower surface of the strip. In this case, as a general rule, it is preferable to alternately arrange the electrolytic treatment tanks provided with the inverted L-shaped edge masks and the electrolytic treatment tanks provided with the L-shaped edge masks one by one on the electrolytic treatment line. It is also possible to alternately arrange a plurality of tanks as a set. At this time, reverse L on the electrolytic treatment line.
It is preferable to arrange the same number of electrolytic treatment tanks provided with the L-shaped edge mask and electrolytic treatment tanks provided with the L-shaped edge mask.

The preferred construction, operation and effect of the present invention will be described below in the case where a steel sheet is electrogalvanized by a horizontal continuous electrogalvanizing apparatus. As shown in FIGS. 1 to 5, an electrode (anode) 2 horizontally arranged with an interval vertically is provided in an electroplating bath (plating bath) 1 formed by upper and lower box-shaped baths 1A and 1B. While the steel plate 3 is running in the direction of the arrow in the plating solution 10 filled in between, electric power is supplied from the conductor rolls 4 installed on the inlet side and the outlet side of the electrode 2 to perform electroplating. The plating solution 10 is jetted from the downstream side of the plating tank 1 between the electrode 2 and the steel plate 3 using the plating solution supply pipe 6 to flow the plating solution 10 in the direction opposite to the steel plate 3, and is discharged from the discharge port 7 on the upstream side. The plating solution 10 enters the receiving tank 8 as in the case of the conventional example described with reference to FIGS. 15 and 16.

In the present invention, the shape of the edge mask 9 for preventing current concentration on both side edges of the steel sheet 3 to be processed is formed in an L shape as shown in FIG.
11 is used as a mask part. Then, for example, as shown in FIG. 3, the edge mask 9 is installed in an inverted L-shape and the plating bath 1 for masking the upper surfaces of both side edge portions of the steel plate 3 with the mask portions 11, and the edge mask 9 as shown in FIG. Is installed in an L-shape and the plating tanks 1 for masking the lower surfaces of both side edge portions of the steel plate 3 are alternately installed in the same number.

The L-shaped edge mask 9 according to the present invention as shown in FIG. 6 is installed in the same horizontal continuous electroplating apparatus as to the U-shaped edge mask 9A of the same size as shown in FIG. When it is used, the number of mask portions 11 adjacent to the steel plate 3 is halved from two to one. Therefore, the probability that the mask portion 11 contacts the steel plate 3 can be halved. As a result, with the L-shaped edge mask 9, the edge mask life is more than doubled as compared with the conventional U-shaped edge mask 9A (FIG. 17) and the U-shaped edge mask 9B (FIG. 18). It can be extended. Further, the L-shaped edge mask 9 shown in FIG. 6 can have a thicker mask portion thickness f than the U-shaped edge mask 9A shown in FIG. 7, and the life can be further extended by improving the strength. it can.

Further, the L-shaped edge mask 9 has the same length e as the U-shaped edge mask 9A and the V-shaped edge mask 9B, but the overall height d can be made thinner. The distance between the electrode 2 and the steel plate 3 can be shortened, and thus the voltage required for the electroplating treatment of the steel plate 3 can be reduced. In the present invention, as shown in FIG. 11 (a), the electrogalvanizing 12 formed on the steel plate 3 is applied to the upper edge portion of the steel plate 3 in the plating tank 1 provided with the inverted L-shaped edge mask 9, for example. Since the current concentration is prevented, the undercoat 12a is formed at the edge portion. On the other hand, in the plating tank 1 provided with the L-shaped edge mask 9, as shown in FIG. 11 (b), since there is no edge mask on the upper edge portion of the steel plate 3, current concentrates and therefore the overcoat 12b is applied to the edge portion.
Is generated.

Therefore, the galvanizing bath 1 having the inverted L-shaped edge mask 9 and the galvanizing bath 1 having the L-shaped edge mask 9 alternately pass through the galvanizing line to be galvanized. As a result, as shown in FIG. 11 (c), the undercoat on the edge portion of the steel plate 3
Steel plate 3 is formed by stacking 12a and overcoat 12b.
It is possible to obtain the electrogalvanized plate 12 in which the edge portion and the other central portion have a uniform thickness.

At this time, the lapping margin between the steel plate 3 and the edge mask 9 is preferably in the range of 3 to 10 mm for uniforming the coating weight.

[0021]

EXAMPLE An L-shaped edge mask 9 (height d = 16 mm, length e = 120 mm, thickness f) of the size shown in FIG. 8 was used in a horizontal continuous electrogalvanizing apparatus as shown in FIGS. = 2 mm), the electroplating treatment tank installed in the inverted L shape and the electroplating treatment tank installed in the L shape are alternately arranged, and while masking the upper surface and the lower surface of the steel plate alternately, 1
An electrogalvanizing treatment was performed on a steel sheet having a width of m with a target areal weight of 30 g / m ² . The distance between the steel plate 3 and the electrode 2 is 10 mm. Figure 12 shows the relationship between the distance from the steel plate edge (mm) and the edge overcoat ratio (%) in this case.

For comparison, as a conventional example, a U-shaped edge mask 9A having a size shown in FIG. 9 (height d = 16 mm, length e =
120mm, thickness f = 2mm) is installed in the electroplating tank, and electrogalvanization is applied to a 1m wide steel plate while masking the upper and lower surfaces of the steel plate at the same time.
The electrogalvanizing treatment was performed at m ² . In this case, the distance from the steel plate edge (mm) and the edge overcoat ratio (%)
Fig. 13 shows the relationship with. The distance between the steel plate 3 and the electrode 2 is 10 mm
Is.

In the case where the conventional galvanizing treatment is carried out at the same target basis weight of 30 g / m ^{2 in} which only the electroplating tank having the L-shaped edge mask is installed and only the lower surface of the steel plate is masked. Distance from steel plate edge (mm)
Fig. 14 shows the relationship between the edge overcoat ratio (%). Here, the edge overcoat ratio is {(amount of zinc per unit area of steel sheet) / (amount of zinc per center area of steel sheet)} × 10
It is 0 (%).

According to the present invention in which the L-shaped edge mask shown in FIG. 12 is alternately installed in the inverted L-shape and the L-shape, the same degree as the conventional example in which the U-shaped edge mask shown in FIG. 13 is installed. The edge overcoat ratio (%) can be maintained. On the other hand, when only the lower surface edge portion of the steel plate is masked by the L-shaped edge mask, the lower surface edge portion of the steel sheet to be masked becomes a significant undercoat as shown in FIG. As a result, an overcoat was formed, which was not desirable.

Table 1 shows a comparison of the results of the present invention example and the conventional example when the electrogalvanizing treatment is performed in this manner.

[0026]

[Table 1]

As shown in Table 1, according to the example of the present invention, not only the edge overcoat preventing effect similar to the case where the U-shaped edge mask is used as described above, but also the steel plate and the edge mask are The number of contacts can be kept to the same level as the conventional example in which the L-shaped edge mask is installed only on the lower surface,
As a result, it was possible to reduce the product defect rate due to flaws on the edge of the steel sheet and extend the life of the edge mask.

As another embodiment, the L-shaped edge mask 9 has an overall height d of 8 mm as shown in FIG.
It can be made as small as possible. Therefore, when the U-shaped edge mask 9A and the U-shaped edge mask 9B are used, the distance between the electrode 2 and the steel plate 3 is at least 10 mm.
However, in the present invention, it can be shortened to about 5 mm. As a result, for example, the plating voltage could be reduced from 17V to 9V.

[0029]

As described above, according to the present invention, the shape of the edge mask for preventing current concentration on both side edges of the metal strip to be processed is L-shaped, and the edge mask is an inverted L-shape. A combination of an electrolytic treatment tank which is formed as a mold so as to mask both side edges of the upper surface of the strip and an electrolytic treatment tank which is made L-shaped so as to mask both side edge portions of the lower surface of the strip are combined on a processing line. Since they are arranged, current concentration on the edge portion of the metal strip can be reduced during double-sided electrolytic treatment.

Further, since the L-shaped edge mask can be made compact and the strength can be improved, it is possible to significantly reduce the frequency of contact with both side edge portions of the steel sheet, and reduce the defective rate of the product due to the contact flaw. At the same time, the life of the edge mask can be extended.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing a horizontal continuous electroplating apparatus according to the present invention.

FIG. 2 is a schematic plan view showing a state in which a plating bath is omitted in FIG.

FIG. 3 is a schematic cross-sectional view showing an arrow AA of FIG.

FIG. 4 is a schematic cross-sectional view taken along the line BB of FIG.

FIG. 5 is a side view showing an L-shaped edge mask according to the present invention.

FIG. 6 is a side view showing the shape of an L-shaped edge mask according to the present invention.

FIG. 7 is a side view showing the shape of a U-shaped edge mask according to a conventional example.

FIG. 8 is a side view showing the dimensional relationship of the L-shaped edge mask according to the present invention.

FIG. 9 is a side view showing a dimensional relationship of a U-shaped edge mask according to a conventional example.

FIG. 10 is a side view showing the dimensional relationship of another L-shaped edge mask according to the present invention.

FIG. 11 is an explanatory diagram showing the superposition of the edge undercoat and the overcoat of the coating weight according to the present invention.

FIG. 12 shows a relationship between a distance (mm) from a steel plate edge and an edge overcoat ratio (%) when the L-shaped edge mask of the present invention is alternately arranged in an inverted L shape and an L shape. It is a diagram.

FIG. 13 is a diagram showing a relationship between a distance (mm) from a steel plate edge and an edge overcoat ratio (%) when a conventional U-shaped edge mask is arranged.

FIG. 14 is a diagram showing a relationship between a distance (mm) from a steel plate edge and an edge overcoat ratio (%) when a conventional L-shaped edge mask is arranged only in an L shape.

FIG. 15 is a schematic sectional view showing a horizontal continuous electroplating apparatus according to a conventional example.

16 is a schematic plan view showing a state where the plating bath is omitted in FIG. 15.

17 is a schematic cross-sectional view showing AA and BB arrows in FIG. 15.

18 is a schematic cross-sectional view showing another conventional example corresponding to the arrows AA and BB in FIG. 15.

FIG. 19 is a schematic sectional view showing a horizontal continuous electric processing apparatus according to another conventional example.

20 is a schematic plan view showing a state in which the plating tank is omitted in FIG. 19.

21 is a schematic cross-sectional view taken along arrows AA and BB of FIG.

[Explanation of symbols]

 1 Electroplating tank (plating tank) 2 Electrode 3 Steel plate 4 Conductor roll 5 Backup roll 6 Plating solution supply pipe 7 Discharge port 8 Receiving tank 9 Edge mask 10 Plating solution 11 Mask part 12 Electrogalvanizing

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuji Kakiyama 1-chome, Mizushima Kawasaki-dori, Kurashiki-shi, Okayama Prefecture (no address) Inside the Mizushima Works, Kawasaki Steel Co., Ltd. (72) Naoki Sakai Mizushima-kawasaki-dori, Kurashiki-shi, Okayama Prefecture 1 chome (without street number) Kawasaki Steel Works Mizushima Steel Works

Claims (3)

[Claims] 1. An edge mask is provided on each side edge portion of a metal strip to be processed which runs in an electrolytic solution filled between electrodes horizontally arranged at intervals in the vertical direction in each tank of a continuous electrolytic treatment tank. In a horizontal continuous electrolytic treatment apparatus for performing electrolytic treatment, the shape of the edge mask for preventing current concentration on both side edge portions of the metal strip to be treated is L-shaped, and the edge mask is inverted L-shaped. On the processing line, combine an electrolytic treatment tank that is formed as a mold so as to mask both side edges of the upper surface of the strip and an electrolytic treatment tank that is formed as an L shape so as to mask both side edges of the lower surface of the strip. A horizontal continuous electrolytic treatment apparatus equipped with an edge mask, which is characterized by being arranged. 2. An electrolytic treatment tank in which an edge mask is formed in an inverted L shape so as to mask both side edge portions of a strip upper surface, and an L-shaped type is installed so as to mask both side edge portions of a strip lower surface. The horizontal continuous electrolytic treatment apparatus provided with the edge mask according to claim 1, wherein the same number of electrolytic treatment tanks are arranged on the treatment line. 3. An electrolytic treatment tank in which an edge mask is formed in an inverted L shape so as to mask both side edge portions of a strip upper surface, and an L-shaped type is installed so as to mask both side edge portions of a strip lower surface. The electrolytic treatment tank and the electrolytic treatment tank are alternately arranged on the treatment line.
A horizontal continuous electrolytic treatment apparatus provided with the edge mask described.