JPS63161200A - 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 treating band steel between negative and positive electrodes in the inlet side former stage in a vertical electrolytic cell and by electrolytically treating the band steel allowed to act as a positive electrode through an electrode roll placed on the outside of the outlet of the cell in the outlet side latter stage. CONSTITUTION:Stainless band steel 6 is passed in the form of U through concd. sulfuric acid as an electrolytic soln. 2 in a vertical electrolytic cell 1. Negative electrodes 7b, 8b and positive electrodes 7a, 8a are vertically arranged in the inlet side former stage in the cell 1 so that the band steel 6 passes between the electrodes. Negative electrodes 11 confronting each other are arranged in the outlet side latter stage. An electrode roll 5 having positive polarity and guiding the band steel is placed on the outside of the outlet of the cell 1 so as to allow the band steel 6 to act as a positive electrode.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Denominator> The present invention relates to an electrolytic treatment apparatus for stainless steel strip that removes scale from heat-treated stainless steel strip.

<Prior Art> Concentrated sulfuric acid electrolytic pickling treatment is required to remove scale from the surface of stainless W steel formed by heat treatment in a low oxygen atmosphere furnace. In this electrolytic pickling treatment, in the first stage, electrolytic treatment may be performed using either an anode or a cathode, but in the latter stage, it is necessary to perform electrolytic treatment using a negative electrode. This is because when electrolytic treatment is performed using a positive electrode, the surface of the steel strip becomes a cathode, and the surface quality of the steel strip deteriorates due to plating effects and the like. For these reasons, in conventional electrolytic treatment apparatuses, an anode is placed in the front stage and a cathode is placed in the rear stage.

FIG. 3 shows an example of a conventional electrolytic pickling treatment apparatus. As shown in the figure, the vertical electrolytic cell 01 has il! Rolls 03, 04, and 05 are filled with an electrolytic solution 02 made of sulfuric acid, and are rotatably disposed in the electrolytic solution 02.
The stainless steel strip 06 guided by the steel strip 06 is threaded through the steel strip 06. Here, 03 and 05 are an inlet roll and an outlet roll provided on the upper and outer inlet and outlet sides of the electrolytic cell 01, and 04 is provided at the inner center lower part of the electrolytic cell 01. This is an intermediate roll. In addition, in the front stage A of the entrance side inside the electrolytic cell 01, there is an entrance roll o3 and an intermediate roll 04.
A pair of positive electrodes 07 are provided on both sides of the stainless steel NTF406 between the
A pair of negative electrodes 08 are provided on both sides of the stainless steel strip o6 between the positive electrode 1!4 and the output roll 05. fI07 and Yin fl! It is connected to the pole 08 by a power source 09.

In this device, a stainless steel band tROS is first guided by an entry roll 03, enters an electrolytic cell 01 from above, is immersed in an electrolytic solution 02, and is immersed in a pair of positive electrodes f! By passing the sheet between F107, both surfaces thereof are electrolytically pickled.

Next, a pair of negative electrodes 08 are guided to the intermediate row kO5.
The plate is then passed between the plates, and the electrolytic pickling treatment on both sides is completed.

Then, the band W406 on which the electrolytic pickling treatment has been completed comes out of the t4 dismantling tank 01, is guided to the tapping roll o4, and is sent to the next process.

<Problems to be solved by the invention> A certain current density and electrolysis time are required to obtain a good surface quality of stainless steel strip using the electrolytic treatment apparatus as described above, so it is necessary to obtain a certain line speed. To achieve this, it is necessary to some extent to lengthen the electrodes, increase the number of electrodes, and even increase the number of vertical electrolytic cells.

Therefore, the length of the steel strip in the electrode tank between the inlet roll and the outlet roll increases, the strip resistance increases, and a large power supply voltage and electric power are required.

In view of these circumstances, an object of the present invention is to provide an electrolytic treatment apparatus for stainless steel strip that can significantly reduce power supply voltage and electric power.

Means for Solving Problems〉 The structure of the present invention for achieving the above-mentioned object is to pass a stainless steel strip in a U-shape into a concentrated sulfuric acid solution in a vertical electrolytic cell, and to In an electrolytic treatment apparatus for stainless steel strip, which performs electrolytic pickling treatment on the stainless steel strip using electrodes provided substantially parallel to each other in the vertical direction so as to sandwich the stainless steel strip,
Positive and negative electrodes having opposite polarities are provided at the front stage of the inlet side of the electrolytic cell, while negative electrodes facing opposite to each other are provided at the rear stage of the outlet side, and at the outside of the outlet side of the f4M tank. is characterized in that an anodic electrode roll is provided to guide the stainless steel strip.

In the electrolytic treatment apparatus having the above configuration, a current flows between the positive and negative 1F electrodes facing each other at the front stage of the input side, and the stainless steel strip passing between them is electrolytically pickled. . Further, at the exit side 12, the stainless steel strip becomes a positive electrode through the electrode port, and a current flows between the stainless steel strip and the opposing negative electrode to perform electrolytic pickling treatment.

Embodiment Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 conceptually shows an electrolytic treatment apparatus according to a first embodiment. As shown in the figure, a vertical electrolytic cell 1 is filled with an electrolytic solution 2 made of concentrated sulfuric acid, and a stainless steel band #I6 is guided by rolls 3 and 4.5 that are rotatably arranged. The plate is threaded through the Ws solution [2]. Here, 3 is the stainless steel band ff4 on the outside of the entrance side.
4 is an intermediate roll provided at the inner center lower part of the electrolytic cell 1, and is the same as the conventional one, but 5 is the exit side external roll that guides the stainless steel band ff4B. Four electrodes (conductor rolls) that become positive with each other
In addition, inside the electrolytic cell 1, in the front stage A, two pairs of electrodes 7ap7b and 8a, 8b are arranged substantially parallel to each other, facing both sides of the stainless steel strip tp16, which is threaded downward. . Here, the electrodes 7a, 7b and 8a, 8b are connected to power sources 9, 10, respectively, and the electrodes 7a, 8a
is an anode, and electrodes 11i7b and 8b are cathodes. On the other hand, inside the electrolytic cell 1, in the rear stage B, a pair of negative electrodes 11 are provided substantially parallel to each other, facing both sides of a stainless steel strip 6 which is passed upward. This cathode 11 is connected to the conductor roll 5 via 'r4[12]. Further, a pair of ringer rolls 13 are rotatably provided outside the outlet side of the electrolytic cell 1 and upstream of the conductor roll 5 to sandwich the stainless steel strip 6 discharged from the electrolytic solution 2 with a predetermined surface pressure. .

Here, the stainless steel strip 6 is guided by the entrance roll 3 and immersed into the electrolysis [2] in the electrolytic cell 1 from above. In the front stage A on the entrance side, electrodes 7a, 7b and 8a, 8b
A plate is passed through the gap, and both sides of the plate are electrolytically pickled. Next, it is guided by the intermediate roll 4 and enters the output rear stage B. In the exit stage B, a plate is passed between the negative electrodes 11, and the stainless steel band tR6 itself becomes a positive electrode via the conductor roll 5, completing the electrolytic pickling process. Then, the stainless steel band lll6 that came out from the electrolyte 2 is attached to the electrolyte 2.
is wiped off with the ring roll 13 and the conductor roll 5
is guided and sent to the next process.

In the device of this embodiment, the positive and negative electrodes are 7 m long at the front stage A on the entrance side.
, 7b and between 8a and 8bli, but the electrical resistance at this time is almost solely the resistance of the electrolyte 2, and the resistance of the stainless steel strip 6 can be almost ignored, so the voltage and power consumption of the power supplies 9 and 10 can be reduced. This can be significantly reduced. Furthermore, since current flows between the stainless steel band tR6 and the negative electrode 11 at the rear end of the output side, the electrical resistance is also reduced, and the voltage and power consumption of the power source 12 are also reduced.

FIG. 2 conceptually shows the second embodiment.
Components similar to those in the drawings are given the same reference numerals and redundant explanations will be omitted. As shown in the figure, in this embodiment, the electrolytic cell 21 is divided into an electrolytic cell 21m at the front stage A on the inlet side and an electrolytic cell 21b at the rear stage B at the outlet side.
These electrolytic cells 21a,
21b has intermediate rolls 4 m and 4 at its inner lower part, respectively.
b, and an intermediate roll 4c is rotatably provided above and outside the boundary. Therefore, the stainless steel strip 6 is used as the entrance roll 3 and the intermediate roll 4a.

4C to pass through the electrolytic solution 2 in the electrolytic cell 21a, and further guided by intermediate rolls 4c, 4b and conductor roll 5 to pass through the electrolytic solution 2 in the electrolytic cell 21b. Here, in the electrolytic cell 21a, positive and negative electrodes 7a, 7b and 8a, 8b are respectively arranged in front and behind the intermediate roll 4a, as in the first embodiment. Electrolytic pickling treatment is then performed. On the other hand, in the electrolytic cell 21b, there are two pairs of negative electrodes 11 similar to those in the first embodiment.
a.

11b are disposed before and after the intermediate four-ring 4b, and the electrolytic pickling treatment is similarly performed. Therefore, in this second embodiment, as in the first embodiment, the voltages and power consumption of the power supplies 9, 10 and 12 are significantly reduced.

Note that the conductor roll 5 used in the first and second embodiments is not immersed in the electrolyte 2, so its structure is simple and maintenance is easy to avoid, such as leakage from the rotary seal and deterioration of the surface quality of the roll. Inspections are reduced.

<Effects of the Invention> As described above in detail with the embodiments, according to the stainless steel strip electrolytic treatment apparatus of the present invention, the current flows between the positive and negative electrodes facing each other in the front stage of the entry side, so that almost The resistance of the steel strip can be ignored since it is only the electrolyte resistance. moreover,
At the latter stage on the exit side, an electrode roll was used, and the stainless steel strip itself was used as a positive electrode, and a current was allowed to flow between this and the opposing negative electrode, so that the liquid resistance was similarly reduced. Therefore, it is possible to reduce the power supply voltage, and the power required for electrolytic treatment can be significantly reduced.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram conceptually showing an electrolytic treatment apparatus according to a first embodiment of the present invention, FIG. 2 is an explanatory diagram conceptually showing an electrolytic treatment apparatus according to a second embodiment, and FIG. FIG. 1 is an explanatory diagram showing an electrolytic treatment apparatus according to the prior art. In the drawing, 1.21 is an electrolytic cell, 2 is an electrolyte, 3 is an inlet roll, 4.4m, 4b, 4a are intermediate rolls, 5 is an electrode roll (conductor roll), 6 is a stainless steel band 1*S 7a, 8m is a positive electrode, 7b, 8b, 11.11m, and 11b are negative electrodes.

Claims (1)

[Claims] A stainless steel strip is passed through the concentrated sulfuric acid electrolyte in a vertical electrolytic cell in a U-shape, and the stainless steel strip is passed through the stainless steel strip in a U-shape through a concentrated sulfuric acid electrolyte. In an electrolytic treatment apparatus for stainless steel strips that performs electrolytic pickling treatment of steel strips, positive and negative electrodes with opposing electrodes having different polarities are provided at the front stage of the inlet side of the electrolytic tank, while the latter stage of the tapping stage is provided with positive and negative electrodes with opposite polarities. An apparatus for electrolytic treatment of stainless steel strip, characterized in that negative electrodes are provided opposite each other, and an anode electrode roll for guiding the stainless steel strip is provided outside the exit side of the electrolytic cell.