JPS63161197A - Apparatus for electrolytically treating stainless band steel - Google Patents

Abstract

PURPOSE:To reduce the resistance of an electrolytic soln. and to save electric power by electrolytically pickling stainless band steel between negative and positive electrodes in the former stage in a horizontal electrolytic cell and with electric current supplied to the band steel through an electrode roll in the latter stage. CONSTITUTION:Stainless band steel 3 is immersed and traveled in concd. sulfuric acid as an electrolytic soln. 2 in a horizontal electrolytic cell 1. Plural pairs of electrodes 4, 5, 9, 8 are arranged above and below the band steel 3 in the inlet side former stage A in the longitudinal direction of the band steel 3 so that each pair of electrodes having opposite polarities confront each other. Plural pairs of negative electrodes 11 are arranged above and below the band steel 3 in the outlet side latter stage B so that each pair of negative electrodes confront each other. An electrode roll 13 having positive polarity and guiding the band steel 3 is placed on the outside of the outlet of the cell 1.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an electrolytic treatment apparatus for removing scale from the surface of a heat-treated stainless steel strip.

<Prior Art> Removal of scale from the surface of a stainless steel strip formed by heat treatment in a low-oxygen atmosphere furnace is usually performed by electrolytic pickling treatment with concentrated sulfuric acid.

In the pre-electrolytic pickling process, it is possible to remove scale by electrolytic treatment using either an anode or a cathode, but in the latter stage, electrolysis with a positive electrode (the surface of the steel strip is the cathode) will cause the surface to be removed due to the pickling effect, etc. Since the properties deteriorate, it is necessary to use a negative electrode (the surface of the steel strip is an anode).

FIG. 2 is a longitudinal cross-sectional view of a main part of an electrolytic pickling treatment apparatus that satisfies the above-mentioned requirements, and 1 is a horizontal electrolytic cell in which an electrolytic solution 2 of concentrated sulfuric acid is placed. An inlet roll 7a and an outlet roll 7b immersed in the electrolytic solution 2 are rotatably installed. 4 and 8 are entry side A in the electrolytic cell 1
run. Positive electrodes 5 and 9 are respectively provided oppositely on both sides of the stainless steel band y43, and cathode Ti electrodes 5 and 9 are respectively provided oppositely on both sides of the stainless steel band fi3 running on the exit side B, and are connected to the respective electrodes R6 and 10. ing.

The stainless steel strip 3 enters the electrolytic solution 1 from the left side in the figure, and is guided by the inlet roll 7a to form the positive electrodes 4 and 8 on the inlet side A and the negative electrodes 5 and 9 on the outlet side B in the electrolytic solution 2. During this time, both surfaces are subjected to electrolytic pickling treatment, and then guided by the exit roll 7b to exit the electrolytic cell 1 and sent to the next step.

<Problems to be Solved by the Invention> By the way, the above-mentioned electrolytic treatment requires a certain current density and electrolysis time in order to improve the surface quality of the stainless steel strip.

Therefore, in order to keep the line speed of the strip constant, a certain length and number of electrodes are required, and the length of the strip in the electrolyte, that is, the distance between the inlet roll and the outlet roll in the electrolytic cell, is In a horizontal electrolytic cell, the deflection of the stainless steel strip guided by each roller becomes large, so the distance between the opposing electrodes becomes large. In this way, as the distance between the upper and lower surfaces of the stainless steel strip and each set of electrodes facing the upper and lower surfaces increases, the electrolyte resistance increases.
Since the length of the steel strip in the electrolytic solution is long, the resistance of the strip from the inlet side (the part facing the positive electrode in the previous stage) to the outlet side (the part facing the negative electrode in the latter stage) also becomes large.

◎Furthermore, multiple circuit currents (secondary
In the example shown, the current flows from the positive electrode 4 to the negative electrode 5, and the current flows from the positive electrode 8 to the negative electrode 5.
Since current flows from the negative electrode 9 to the negative electrode 9, the apparent resistance of the steel strip becomes thicker by the number of circuits, and a larger power supply voltage and power are required.

Therefore, the present invention has been made in order to eliminate the drawbacks of the conventional electrolytic treatment equipment for stainless steel strips mentioned above.
Is the distance between the opposing fS poles of opposite polarity short?(Thus, not only the strip resistance is small, but also the electrolytic resistance is small and the stainless steel strip has a small number of electrodes. No circuit current occurs between the four poles.) The present invention aims to provide an electrolytic treatment device.

Means for Solving the Problems> In order to achieve the above-mentioned object, the stainless steel strip electrolytic treatment apparatus according to the present invention includes a stainless steel strip that runs while being immersed in a concentrated sulfuric acid electrolyte in a horizontal electrolytic tank. Pairs of opposite polarity arranged oppositely on the upper and lower surfaces of the steel entry side, respectively.
A plurality of pairs of ls electrodes are sequentially arranged in the length direction of the stainless steel strip, while pairs of negative electrodes are arranged facing each other on the upper and lower surfaces of the outlet side of the stainless steel strip, and It is characterized in that an anodic electrode roll for guiding the stainless steel strip is provided on the outside of the exit side.

Due to the above structure, in electrolytic pickling treatment in the pre-stage of stainless steel strip, the stainless steel strip is The electrical resistance of steel can be reduced. Further, on the output side, electricity is applied to the stainless steel strip through an electrode roll to serve as a positive electrode, and a current is passed between the stainless steel strip and the negative electrode to perform a post-electrolytic pickling treatment on the stainless steel strip.

Embodiment Next, a typical embodiment of the present invention will be described based on the drawings. However, in FIG. 1, which shows the main structure of the stainless steel strip electrolyzer of the embodiment, the same members as in the conventional device (FIG. 2) are designated by the same reference numerals, and redundant explanation will be omitted.

That is, in FIG. 1, 4 and 8 are positive electrodes, and 5 and 9 are negative electrodes, and positive and negative electrodes are alternately arranged on both sides of the stainless steel band @ 3 running on the entrance side A of the electrolytic cell 1 so that the polarities are different. and are connected to respective power sources 6 and 10, respectively.

Reference numeral 11 denotes negative electrodes for the latter-stage electrolytic treatment of the steel strip, which are provided opposite to each other at two locations on both sides of the stainless steel strip 3 running on the exit side B of the electrolytic cell 1.

13 is a positive fundactor roll, which is located on the outlet side B of the electrolytic cell 1.
It is rotatably installed externally, and holds the stainless steel strip 3 between the presser roll 14 and the presser roll 14 . The negative electrode 11 and the conductor roll 13 are connected to a power source 12. 1
Reference numeral 5 denotes a pair of Ringer rolls, which are rotatably installed so as to sandwich the stainless steel strip 3 between the surface of the decomposition solution 2 and the conductor roll 13 with a predetermined surface pressure.

The stainless steel strip 3 enters the electrolytic cell 1 from the left side in the figure, and when passing between the anode 4 and the cathode 5 on the inlet side A, both sides are subjected to the electrolytic pickling treatment in the previous stage, and then the stainless steel strip 3 is subjected to the electrolytic pickling treatment in the previous stage. On side B,
A positive current is applied from the power source 12 through the conductor roll 13 to form an anode, and the plate is passed between each cathode 11 to complete the electrolytic pickling process. Then, the electrolytic solution 2 that has come out and adhered to the electrolytic solution 2 is wiped off with a ringer roll 15, and passed between the conductor roll 13 and the presser roll 14 to be sent to the next process. At this time, current flows only between the anode and cathode electrodes 4, 5 and 8, 9 having different polarities on the inlet side A, and their electrical resistance is almost only the resistance of the electrolyte 2, and the resistance of the stainless steel strip 3 is almost negligible.

<Effects of the Invention> As is clear from the above description, according to the electrolytic treatment bag for stainless steel strip according to the present invention, on the entry side of the electrolytic tank (horizontal type), the bag for electrolytic treatment of stainless steel strip is provided oppositely on both the upper and lower surfaces of the stainless steel strip. Since current flows between the positive and negative electrodes, only the electrolyte resistance exists, and the resistance of the steel strip is so small that it can be ignored.
By using an electrode roll on the output side, the electric circuit is combined into one set, which reduces the resistance of the electrolyte and reduces the power supply voltage required for the device, resulting in a significant reduction in the power required for electrolytic treatment. savings can be made.

Furthermore, since the electrode roll is not immersed in the electrolytic solution, the structure of the device is simplified, and there is also the advantage that maintenance and inspection for liquid leakage from the rotating seal portion and deterioration of the surface quality of the electrolytic roll can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of main parts showing a schematic configuration of an electrolytic treatment apparatus for stainless steel strip according to an embodiment of the present invention, and Fig. 2 is a longitudinal cross-sectional view of main parts showing the structure of a conventional electrolytic treatment apparatus for stainless steel strip. It is. In the diagram, A...inlet side of stainless steel strip, B...outlet side,
DESCRIPTION OF SYMBOLS 1... Electrolytic cell, 2... Electrolyte, 3... Stainless steel strip, 4... Positive electrode, 5... Negative electrode, 8... Positive electrode, 9... Negative electrode, 11 ...Cathode electrode, 13...Conductor roll.

Claims (1)

[Claims] A plurality of pairs of electrodes with opposite polarities are arranged facing each other on the upper and lower surfaces of the entrance side of a stainless steel strip that is immersed in a concentrated sulfuric acid electrolyte solution placed in a horizontal electrolytic tank and runs. While disposing them sequentially along the length direction, negative electrodes are arranged in pairs on the upper and lower surfaces of the outlet side of the stainless steel strip, respectively, and facing each other, and the stainless steel strip is guided to the outside of the outlet side of the horizontal electrolytic cell. An electrolytic treatment device for stainless steel strip, characterized by being equipped with an anodic electrode roll.