JPS63128196A - Method and device for energizing in continuous electrolytic treatment of metallic strip - Google Patents

Abstract

PURPOSE:To surely prevent the arc spot on the contact face between the metallic strip and a conductive roll without causing an electric discharge and to dispense with a current collector provided with a brush by carrying out the passage of a current between the metallic strip and an electric conductor through a liq. metal. CONSTITUTION:The liq. metal 13 such as a low-m.p. alloy bath is charged in a vessel 11 housing a roll 12 for conveying the metallic strip 1 in the amt. sufficient for immersing a part of the roll 12. A bath 14 having higher m.p. than the metal 13 is provided over the metal 13, and the metal 13 is kept in a molten state. A part of the conductor 16 connected to an electrolytic power source is immersed in the metal bath 13, and a current is passed between the metallic strip 1 conveyed by the roll 12 and the conductor 16 through the liq. metal 13. By this method, a stabilized good-quality product is obtained, and the maintenability of every kind can be improved.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention is directed to electric current application in continuous electrolytic treatment of a metal strip, which is suitable for electrically polishing, descaling, cleaning, plating, coloring, etc. the surface of a metal strip. METHODS AND APPARATUS.

[Prior Art] Generally, in continuous electrolytic treatment lines such as metal strip plating equipment or electrical cleaning equipment that conduct large currents, one or more current-carrying rolls are provided, and the current-carrying rolls and the metal strips are energized. To ensure good performance, a presser roll is attached to press the metal strip against the current-carrying roll. By the way, when a relatively high current is transferred between the current-carrying roll and the metal strip, discharge often occurs at the contact surface between the current-carrying roll and the metal band, and the surface of both the metal band and the current-carrying roll is
Arc spots on the surface of the metal strip, which generally leave traces called arc spots, reduce the product value of the metal strip due to their defects, and arc spots on the surface of the current-carrying roll cause new arc spots to occur in a chain reaction. becomes.

Therefore, as a conventional method for preventing arc spots, that is, a method for preventing the occurrence of a discharge phenomenon at the contact surface between the metal strip and the current-carrying roll, for example, the material of the current-carrying roll has been changed.

The surface shape, roughness, and cleanliness of the current-carrying roll, the pressure roll blade, the tension and surface straightening of the metal band, or JP-A-53-
Various improvements and countermeasures have been made, such as the method for preventing the hydroplane phenomenon described in Japanese Patent No. 43832.

[Problems to be Solved by the Invention] However, even if the above-mentioned conventional measures are adopted, there are cases where the current per energized roll reaches a drinking ampere,
When the line speed is as high as several 100 m/min or when the thickness of the metal strip is very thin, a sufficient arc spot prevention effect cannot be obtained.

Further, when a current-carrying roll is used, a current collector is attached, but when a large current is applied, troubles such as breakage and burnout of the brushes of the current collector are likely to occur.

In addition, Japanese Patent Application Laid-Open No. 110-234997 proposes a device using a low melting point full bending device as a collecting device attached to an energizing roll. According to this collection '11t92t, troubles such as brush damage and burnout can be resolved, but
It is not possible to prevent arc spots from occurring on both the surface of the energizing roll and the surface of the metal strip.

The purpose of the present invention is to reliably prevent the above-mentioned arc spots without causing the discharge phenomenon that occurs at the contact surface between the metal strip and the current-carrying roll, and to eliminate the need for a current collector equipped with a brush or the like. do.

[Means for Solving the Problems] The present invention provides an energization method in continuous electrolytic treatment of a metal strip, in which current is passed between a conductor connected to a power source and the metal strip. The current is applied through the liquid metal.

The present invention also provides an energizing device for continuous electrolytic treatment of a metal strip in which current is passed between a conductor connected to a power source and a metal strip, in which a roll for transporting the metal strip is placed in a container penetrated with the roll. An amount of liquid metal is charged to immerse at least a portion of the conductor, and the conductor is placed in the container so as to immerse at least a portion of the conductor in the liquid metal bath, and the metal is transported into the container by the rolls. Current is passed between the band and the conductor using liquid metal.

[Function] According to the present invention, since the conductor and the metal strip are smoothly energized through a liquid metal bath, there is no need to use a conventional energizing roll or current collector, and therefore the contact surface of one energizing roll is The arc spot can be reliably prevented without causing the discharge phenomenon that occurs in the above. Further, a current collector equipped with a brush or the like is not required, and troubles such as brush breakage and burnout do not occur.

[Example] Fig. 1 is a sectional view showing an energizing device according to an embodiment of the present invention, Fig. 2 is a side sectional view taken along arrow II-II in Fig. 1, and Fig.
The diagram shows a schematic diagram of an electrolytic treatment line for metal strips. In the electrolytic treatment line shown in FIG. 3, 1 is a steel strip, 2 is an electrolytic tank, 3 is a rinsing tank, 4 is a current supply device, and 5 is a DC power source.

Connoisseur? lt'& is a container 11 in which a conveying roll 12 of a steel strip l is horizontally inserted, and an amount of liquid metal 1 is placed in the container 11 in an amount to immerse a part or all of the conveying roll 12.
3 is loaded. 12A is a sealing device. Although mercury can be used as the liquid metal 13, preferably bismuth,
It consists of a low melting point alloy bath whose main ingredients are lead, tin, etc., and which melts at about 80°C.

Note that a hot water bath 14 having a temperature higher than the melting point of the liquid metal 13 is provided above the liquid metal 13 . The liquid metal 13 is directly heated in contact with the hot water bath 14 and kept in a molten state, WJJ
The bath 14 is heated to about 80° C. by a steam pipe 15.

Further, the energizing device z4 includes a conductor 16 connected to the power source 5. The lower part of the conductor 16 is covered with the liquid gold m1.
It is placed inside the container 11 so as to be immersed in the M1 bath of the container 11 and facing the conveying roll 12, and its upper part is immersed in the M1 bath of the container 11.
It is fixed with bolts 7. As a result, the conductor 16
The steel strip 1 transported into the container 11 by the transport rolls 12 can be energized via the liquid metal 13.

The phenomenon in which the liquid metal 13 adheres to the steel strip 1 and is carried away can be prevented by keeping the liquid metal 13 in a molten state in the hot water bath 14, but it can be more reliably prevented by the following two means. The first means is by a rotating brush 18, and the second means is by a hot water injection nozzle 19.

In other words, one rotating brush 18 is installed in the vicinity of the surface of the hot water bath 14 on the side where the steel strip 1 is sent out, so as to be in contact with both the front and back surfaces of the steel strip 1. and rotate in the opposite direction.

Further, the hot water injection nozzle 19 is arranged above the rotating brush 18, and the hot water injection nozzle 19 is arranged above the rotating brush 18, and the hot water injection nozzle 19 is arranged above the rotating brush 18. Steel strip 1 is heated with hot water above the melting point of
Spray toward both sides of the N side. Here, the container 11 is provided with a plurality of hot water supply pipes 20 communicating with the hot water bath 14, and the tip of each hot water supply pipe 20 is connected to a hot water injection nozzle 19 via a spout (not shown). is connected and pump 2
The hot water pumped by the steel strip 1 is uniformly sprayed onto both the front and back surfaces of the steel strip 1.

Hereinafter, the operation of the electrolytic treatment line using the energizing device 4 will be explained.

The steel strip l that has been electrolyzed in the electrolytic bath 2 and is conveyed at a constant speed to the energizing device 4 of the present invention via the rinsing bath 3 is transferred from the conductor 16 to the liquid metal 13 on the circumferential surface E of the conveying roll 12.
energized through the electrolytic cell 2, which enables the electrolytic treatment of the steel strip l in the electrolytic cell 2. Since the conductor 16 and the steel strip 1 are completely electrically connected by the liquid metal 13, there is no discharge phenomenon in this current-carrying portion, and arc spots can be reliably prevented.

The steel strip l that has come out of the liquid metal 13 passes through a hot water bath 14 and is #4
Rotating brushes 18 arranged on both the front and back sides of the band l
．． It passes between the hot water injection nozzles 19.

It is carried out from the energizing device 4 through the opening of the lid 17. During this time, the low melting point alloy that has been cooled by the steel strip 1 and has solidified and adhered to the partial dents and scratches on the steel strip 1 is melted and dropped again in a hot water bath at 80°C, and the remaining low melting point alloy is The rotary brush 18 mechanically scrubs the dirt completely, and the hot water sprayed from the spray nozzle 19 ensures even greater safety.

In the above embodiment, the steam used to heat the hot water bath 14 may of course be replaced with an electric heater, and hot water heated externally may be circulated using a liquid feed pump or the like. In high-speed operation where the line speed reaches several hundred txI minutes, multiple pairs of rotating brushes 18 may be provided.The main point of the present invention is to use the liquid metal 13 to energize the steel strip 1. In particular, the transport roll 12 does not necessarily need to be made of an electrically conductive material.

The effects of the energizing device 4 are summarized below.

■Arc spots, a drawback of conventional energized rolls, are completely eliminated.

■Since the current-carrying rolls used in conventional equipment are no longer required, work that requires strict restrictions regarding roll material, shape, and surface roughness is no longer necessary.

■Restrictions on the surface quality and shape correction of metal strips have been significantly relaxed.

Since the lΦ TEPCO equipment is no longer needed, there is no longer any work such as aligning the collector ring and the current-carrying roll shaft, or replacing damaged brushes.

(φ As a result of the above φ to ■, a stable and high quality product was obtained, and various maintainability was significantly improved.

[Effects of the Invention] As described above, according to the present invention, the above-mentioned arc spot can be reliably prevented without causing the discharge phenomenon that occurs at the contact surface of the metal strip and the current-carrying roll, and the brush etc. can be provided. Power collection? c: It is possible to make v1 uneasy.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an energizing device according to an embodiment of the present invention, FIG. 2 is a side cross-sectional view taken along arrow II-II in FIG. 1, and FIG.
The figure is a schematic diagram showing an electrolytic treatment line for metal strips. Conveying roll, 13...liquid metal, 16...conveying body. Agent Patent Attorney Osamu Shiokawa Figure 1 Figure 2 Figure 3

Claims (2)

[Claims] (1) In the energization method in continuous electrolytic treatment of a metal strip, in which current is passed between the conductor and the metal strip connected to a power source, the current is passed between the conductor and the metal strip via liquid metal. Characteristic method of applying electricity in continuous electrolytic treatment of metal strips. (2) In an energizing device for continuous electrolytic treatment of a metal strip, in which current is passed between a conductor connected to a power source and a metal strip, at least a portion of the roll is placed in a container penetrated with a roll for transporting the metal strip. The conductor is placed in the container so that at least a portion of the conductor is immersed in the liquid metal bath, and the conductor is placed in the container so as to be immersed in the metal strip conveyed into the container by the rolls. An energizing device for continuous electrolytic treatment of a metal strip, characterized in that energization between the body and the body is carried out using liquid metal.