JPH0853786A - Pickling device of metallic strip - Google Patents

Abstract

PURPOSE:To prevent falling of pickling liquid onto metallic strip surface. CONSTITUTION:Pickling liquid receivers 3 are hung between sink rolls 1 and the metallic strip 2 in a bypass stage of passing the metallic strip 2 without immersing the strip into the pickling liquid 6 while allowing the sink rolls 1 to stand by in standby positions above the metallic strip 2. These pickling liquid receivers 3 are formed approximately to a shallow boat or trough shape, are formed longer than the width of the metallic strip 2 and are provided with inclination in such a manner that the central parts of the bases are made higher than both ends. The pickling liquid receivers are provided with holes 8 at both ends and are moved by moving devices 10. The pickling liquid receivers 3 stand by in the state of floating on the surface of the pickling liquid 6 or in the state of parting from the surface in a pickling stage for pickling the metallic strip 2 by descending of the sink rolls 1 to press the metallic strip. Spray devices 7 or 9 to blow air to the front surfaces of the sink rolls 1 or the rear surfaces of the pickling liquid receivers 3 are installed near the standby positions of the sink rolls 1 to remove the pickling liquid 6 adhering and remaining on the surfaces in the pickling process.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for pickling metal strips which are continuously threaded, and more particularly to an apparatus for pickling metal strips whose pickling conditions can be changed.

[0002]

2. Description of the Related Art Metal strip products such as stainless steel sheets are produced on the surface of metal strips in a manufacturing process such as an annealing process for removing an influence of work hardening in a hot rolling process or a cold rolling process. (Hereinafter referred to as scale)
Layers are generated. This scale has a hard and brittle property. For example, when cold rolling is performed with the scale left, the cold rolling roll having a smooth surface and a beautiful finish may be damaged. At the same time, cold rolling causes rolling with scratched cold rolling rolls and scales to be caught on the surface of the metal strip, which reduces the surface quality of the metal strip and ultimately the metal strip product. The product value may decrease or may not become a product. Therefore, a good quality product cannot be produced unless the scale layer on the surface of the metal strip is completely removed before cold rolling. To this end, a wide variety of descaling methods have been proposed and implemented.

The descaling method includes chemical treatment such as pickling treatment or electrolytic treatment using various acids or salts, mechanical treatment such as shot blasting treatment, repeated bending treatment, brushing treatment, or the like. Methods such as combined treatment of chemical treatment and mechanical treatment are used. The most basic and widely practiced treatment method is a continuous pickling solution consisting of sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid, etc. or a mixed acid of said acids, such as a mixed acid of nitric acid and hydrofluoric acid. It is a pickling treatment in which the metal strip is dipped in, and the scale is dissolved and peeled off. In such a descaling method that performs only pickling treatment, there is a demand for high-speed processing of metal strips that are continuously threaded to improve productivity, and safe descaling to obtain a final product with good surface quality. Since it is difficult to satisfy the conditions, as described above, a chemical treatment such as an electrolytic treatment, a mechanical treatment such as a brushing treatment, or a combination of these treatments may be performed before the pickling treatment. . In some cases, descaling may be performed by performing the above-mentioned treatment without performing the pickling treatment. Furthermore, for stainless steel and the like, it is necessary to combine the pickling solution and the electrolysis in accordance with the type of steel and use them properly.

The descaling process is thus a combination of various processing processes, and these descaling processes form a production line integrated with an annealing process or the like. In the production line, both metal strips subjected to pickling treatment with a specific pickling solution in the descaling step and metal strips not subjected to pickling treatment may be passed through the same production line. is there. Further, there is a case where only a specific pickling solution of a plurality of pickling solutions in the same production line is not subjected to pickling processing.

FIG. 5 is a block diagram of a pickling apparatus using the first conventional technique. When performing pickling treatment, sink roll 1
As shown by the phantom line, 1 presses the metal strip 12 that is continuously passed through the plate to immerse it in the pickling solution 16 in the pickling tank 15 to perform pickling treatment. At this time, part of the sink roll 11 is also immersed in the pickling solution 16. When the pickling process is not performed, the sink roll 11 moves up to the standby position, and the metal strip 12
Is not pressed, it bypasses and passes through the upper part of the pickling tank 15 without being immersed in the pickling solution 16. By raising and lowering the sink roll 11 as described above, the pickling process in which the pickling process is performed and the bypass process in which the pickling tank is passed without performing the pickling process are switched.

In the pickling step, since a part of the sink roll 11 is also immersed in the pickling solution 16, the pickling solution 16 is attached to the surface of the sink roll 11, and then the bypass step is switched to the pickling step. When the metal strip that is not desired to be continuously threaded is passed through, the pickling solution 16 drops (drops) from the sink roll 11 standing by at a position higher than the metal strip 12 and the surface of the metal strip that is not desired to be pickled. In contrast, the surface properties of the metal strip deteriorated over a considerable length in the lengthwise direction of the metal strip, such as the part that dropped (dropped) locally changes the surface texture, and the surface of the metal strip continuously threaded in the bypass process. It lowers the quality and thus the product yield. In order to prevent the deterioration of the surface quality, in the conventional technique, a dummy metal band or a dummy coil is provided between the metal band that is pre-pickled and the metal band that is not pickled by the bypass process. The pickling solution 16 is dropped (dripping) after joining, sandwiching and passing through continuously.
Since the end of, has been switching metal bands in earnest.

Further, as a second conventional technique for preventing the deterioration of the surface quality, Japanese Utility Model Laid-Open No. 6-4066 is disclosed. FIG. 6 is a block diagram of a pickling apparatus using this conventional technique. In the conventional technique, when the bypass process is switched to, the sink roll 11 standing by at the upper portion of the metal strip is washed with the washing water spray device 19 for washing and then dried with the air spray device 20 for drying. Pickling solution 16
Is removed. Further, a removal air spray device 21 for removing the pickling solution 16 adhering to the metal strip is installed on the inlet side of the sink roll 11 at the standby position. For example, the pickling solution 16 is removed by blowing compressed air from the removing air spray 21 onto the surface of the metal strip.

[0008]

SUMMARY OF THE INVENTION In the first prior art,
In order to prevent the deterioration of the surface quality of the metal strip during bypass, a dummy metal strip or coil is sandwiched between the metal strip to be pickled and the metal strip not to be processed, so it is an unnecessary dummy. However, there is a problem that the manufacturing cost is increased and the efficiency and productivity are reduced due to useless strip passing.

In the second conventional technique, the sync roll 1 is used.
The waste liquid obtained by washing 1 is dropped or attached to the pickling tank or the surface of the metal strip. By dropping this waste liquid into the pickling tank, the concentration of the pickling solution in the pickling tank changes and the pickling state changes, and the pickling solution management becomes complicated, difficult, and heavy load, and above all, scale surely. It is difficult to remove, and in order to keep the concentration of a large amount of pickling solution constant, it is necessary to add acid or water to the pickling solution in the pickling tank to adjust the concentration uniformly. Problems such as poor pickling of the metal strip being adjusted and an increase in proportional costs arise. There is also a problem that the surface shape is deteriorated due to the waste liquid adhering to the surface of the metal strip. In order to prevent the deterioration, at present, a dummy metal strip is joined and sandwiched between the metal strip subjected to the pickling treatment and the metal strip not subjected to the pickling, and the strip is continuously threaded, as in the first conventional technique. . For this reason, work efficiency is reduced.

In any of the first and second prior arts, the above-mentioned several problems appear when switching between the pickling step and the bypass step. Therefore, various preventive measures are taken during the switching. It is necessary to prepare a dummy metal band which is originally unnecessary and to use it while bonding or separating it, which increases the manufacturing cost and lowers the efficiency and productivity.

An object of the present invention is to provide a pickling device for a metal strip which has a simple structure and can easily and reliably prevent the pickling solution from dropping (dripping) on the surface of the metal strip. .

[0012]

According to the present invention, a metal strip is immersed in a pickling bath for removing an oxide layer from the surface of a metal strip which is continuously threaded, or a metal strip is pulled from the pickling bath. A metal strip pickling device having a sink roll capable of being bypassed, the metal strip including a pickling solution receiver inserted between the sink roll and the metal strip when the metal strip is bypassed. It is a strip pickling device. Further, the present invention is characterized in that a spray device for blowing air to the surface of the sink roll is provided in the vicinity of the position of the sink roll when the metal strip is bypassed. Further, the pickling solution receiver of the present invention,
It is generally formed in a shallow boat shape or gutter shape, is longer than the plate width of the metal strip, and is inclined so that the center part of the bottom surface is higher than both ends, and holes are formed at both ends. It is characterized by being provided. Further, the pickling solution receiver of the present invention is hung on both roll necks of the sink roll or in the vicinity thereof, and is moved away from directly below the sink roll when the metal strip is immersed, and floats on the surface of the pickling liquid. It is characterized in that it is held in a state of being kept in a state of being separated from the surface of the pickling solution.
Further, the present invention is characterized in that a spray device for blowing air to the back surface of the pickling solution receiver is provided in the vicinity of the pickling solution receiver when the metal strip is bypassed.

[0013]

According to the present invention, the sink roll is for immersing the metal strip in the pickling bath for removing the oxide layer from the surface of the metal strip, or for pulling the metal strip from the pickling bath to bypass it. It is possible. By inserting the pickling solution receiver between the sink roll and the metal band when bypassing the metal strip, the pickling liquid drop (dripping) from the surface of the sink roll can be received by the pickling liquid receiver, and continuous stripping It is possible to easily and reliably prevent the pickling solution from dropping (dripping) on the surface of the metal strip along the longitudinal direction thereof.

Preferably, an air spray device for blowing air to the surface of the sink roll is provided near the position of the sink roll when the metal strip is bypassed. Therefore, the pickling solution adhering to the surface of the sink roll can be removed and the sink roll can be removed. The surface can be dried.

Preferably, the pickling solution receiver is formed in a generally shallow boat shape or a gutter shape so that it is longer than the plate width of the metal strip and the central portion of the bottom surface is higher than both end portions. Since there is a slope on each side and holes are provided at both ends, the pickling solution that has fallen (dropped) on the pickling solution receiver and accumulated is not attached to the metal strips at all in the pickling tank. Can be returned as is.

[0016] Preferably, the pickling solution receiver is hung on both roll necks of the sink roll or in the vicinity thereof, and is moved from directly under the sink roll when the metal strip is immersed, and floats on the surface of the pickling liquid. The sink roll presses the metal strip into the pickling bath in the pickling bath when the metal strip is immersed, because the sink roll is held in the pickling bath in a state of being kept away from the surface of the pickling bath. At this time, since the pickling solution receiver is not directly under the sink roll, it can be prevented from becoming an obstacle at all.

Preferably, a spray device for blowing air to the back surface of the pickling solution receiver is provided near the pickling solution receiver when the metal strip is bypassed. The pickling solution that leaks and adheres to the back surface from the holes provided at both ends can be scattered and removed, and the pickling solution drops (drops) on the surface of the continuously running metal strip in the longitudinal direction. It can be prevented easily and surely.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a front view of a pickling apparatus according to an embodiment of the present invention. FIG. 2 shows the pickling solution receiver 3 used in FIG.
FIG. FIG. 3 shows a transfer device 10 for the pickling solution receiver 3.
It is a side view of a pickling apparatus according to an embodiment of the present invention in which is omitted. FIG. 4 is a perspective view of a pickling apparatus according to an embodiment of the present invention.

As shown by the solid line in FIG. 1, a plurality of pickling processes in the same production line as a bypass process in which a metal strip that is continuously threaded is passed without pickling, or in the same production line, each holding various pickling solutions. Depending on the type of metal strip in the tank and surface finishing conditions, the sink roll 1 may be placed at a higher standby position than the metal strip 2 when bypassing the metal strip without passing it through a specific pickling tank. stand by. This Figure 1
As shown in FIG. 4 and FIG. 4, the sink roll 1 is pivotally supported by bearings 1b at the ends of both roll necks 1a. The bearings 1b are vertically moved between predetermined positions by a drive source such as a hydraulic cylinder. Configured to work. And although the sync roll 1 itself is not shown,
There are a rotatable type that comes into contact with the metal strip 2 that is continuously threaded and rotates together, and a type that includes a bias rotation (helper drive) means.

Further, as shown in FIG. 3, between the sink roll 1 and the metal strip 2 which is continuously threaded,
A pickling solution receiver 3 is provided. The pickling solution receiver 3 is hung from both roll neck portions 1a of the sink roll 1 or the vicinity thereof by a flexible hanging string or something similar thereto. When the sink roll 1 is at the waiting position in the bypass process, the pickling solution receiver 3 is directly below (immediately below) the sink roll 1 and the metal strip 2 is provided.
It is held in an intermediate position just above. Further, as shown in FIG. 1, the pickling solution receiver 3 is fixed to one end of the pickling solution receiver 3 when the sink roll 1 is at the position shown by the phantom line in the pickling step of immersing the metal strip 2. Directly below the sink roll 1 (directly below) by activating the moving device 10 including the flexible moving string 10a or an equivalent thereof.
Is moved from the surface of the sink roll 1 and is kept floating on the surface of the pickling solution 6 on the side of the sink roll 1, or is kept so as not to be immersed away from the surface of the pickling solution 6. Such a moving device 10 is composed of, for example, a moving cord 10a, a guide pulley, a hydraulic cylinder, and the like, and is provided between the time when the metal strip 2 is bypassed and the time when the metal strip 2 is immersed in the pickling solution 6, and the sink roll 1 is used.
The pickling solution receiver 3 itself can be moved from the waiting position to the holding position under any state in association with the raising and lowering operation between the predetermined positions.

In particular, by such a restricted operation of the moving device 10, even when the metal strip 2 is immersed, the pickling solution receiver 3 is accurately held at the holding position under any state, and the pickling solution is picked up. It cannot move freely in the tank 5.

Therefore, in the pickling step of immersing the metal strip 2, the pickling solution receiver 3 is held in a state of floating on the surface of the pickling solution 6 before and after the sink roll 1 or in a state of being not dipped away from this surface. While waiting, the sink roll 1 can be lowered to the position indicated by the phantom line without any trouble, and the metal strip 2 can be pressed to be immersed in the pickling solution 6.
Further, in the bypass step, the sink roll 1 rises and stands by at a predetermined waiting position, and the metal strip 2 continuously threaded does not come into contact with the sink roll 1 or the pickling solution receiver 3 etc. Pass above 5. At this time, since the pickling solution receiver 3 is moved and held at an intermediate position just below the sink roll 1 and directly above the metal strip 2, the pickling solution dropping (dripping) from the sink roll 1 is received on the way. It is possible to prevent it from reaching the surface of the metal strip 2 which is continuously threaded below.

In the bypass step, a spray device 7 is provided near the standby position of the sink roll 1, and the spray device 7 adheres to the sink roll 1 by blowing compressed air onto the surface of the sink roll 1, for example. The pickling solution is quickly removed, and the sink roll 1 is dried. On the other hand, when the pickling solution receiver 3 is immersed in the pickling solution 6, it adheres to the back surface of the pickling solution receiver 3 which is moved to an intermediate position right above the metal strip 2 and held at the waiting position. In some cases, the pickled solution left over may remain, or the pickled solution dropped (dropped) from the sink roll 1 may leak from the holes provided at both ends and remain attached. Also, the pickling solution receiver 3 held in the waiting position
Since the spray device 9 for blowing air to the back surface of the pickling solution receiver 3 is provided in the vicinity of, the pickling solution remaining on the back surface can be quickly scattered and removed. It is possible to reliably prevent the pickling solution from dropping (dripping) on the surface of the metal strip 2 which is continuously threaded downward in the longitudinal direction.

As shown in FIG. 2, the pickling solution receiver 3 is formed in a shallow boat shape or a trough shape, and has a bottom center portion 3a.
Has a structure in which the slope is provided so that the height is higher than both ends 3b. In addition, holes 8 are formed at both ends 3b.
Is provided. The pickling solution receiver 3 and the moving string 10a of the moving device 10 fixed to the pickling solution receiving tool 3 or the like are placed in the pickling tank 5 and immersed in the pickling solution 6 or the pickling solution Since vapor or scattered pickling solution adheres, it is not affected by such pickling solution, for example, synthetic resin or synthetic fiber having sufficient acid resistance. Even if it is fully lined with such a synthetic resin, it can be suitably used.

As shown in FIG. 3, the width of the pickling solution receiver 3 is wider than the width of the metal strip 2. In the bypass step, the pickling solution receiver 3 moves to an intermediate position just below the sink roll 1 and directly above the metal strip 2, and receives the pickling solution 6 falling (dripping) from the sink roll 1. As described above, the pickling solution receiver 3 has the central portion 3a on the bottom surface thereof.
Has a structure so that it is higher than both ends 3b, the pickled solution 6 received is moved to both ends 3b of the pickled solution receiver 3 and is provided at both ends 3b thereof. It is discharged from the hole 8 and directly drops into the pickling tank 5. At this time, since the lateral length of the pickling solution receiver 3 is wider than the plate width of the metal strip 2, the pickling solution 6 does not drop and adhere to the surface of the metal strip 2 and directly drop into the pickling tank 5. To do.

As shown in FIG. 4, the spray device 7 is installed near the standby position of the sink roll 1 in the bypass process. The spray device 7 is fixed, for example, at two positions diagonally above the standby position of the sink roll 1, and sprays, for example, compressed air onto the surface of the sink roll 1 which is moved to and held at the standby position. As a result, the pickling solution 6 attached to the surface of the sink roll 1 is forcibly collected under the sink roll 1 and the surface of the sink roll 1 can be dried. The pickling solution 6 collected in the lower part of the sink roll 1 falls into the pickling solution receiver 3 and directly into the pickling tank 5 through the holes 8 at both ends of the pickling solution receiver 3. If the spray device 7 is provided diagonally below the standby position of the sink roll 1 and compressed air is blown to the surface of the sink roll 1 held at the standby position, the surface of the sink roll 1 can be moved faster. It can be dried.

[0027]

As described above, according to the present invention, the metal strip is immersed in the pickling solution in the pickling tank to remove the oxide layer from the surface of the metal strip, or the metal strip is removed from the pickling tank. It is possible to pull up and bypass without dipping without any trouble. By inserting a pickling solution receiver between the sink roll and the metal band when bypassing the metal strip, the pickling solution adhering to the surface of the sink roll can be received by the pickling solution receiver, and the pickling solution on the surface of the metal strip. Can be prevented from falling. As a result, the product yield can be improved without deteriorating the surface quality of the metal strip continuously threaded in the bypass step. Further, it is possible to provide a metal product finished with good surface quality and surface finish. Further, since it is not necessary to join and sandwich the dummy metal band and the coil, the production efficiency such as efficiency and productivity is improved, and the switching between the bypass process and the pickling process is quick, easy and reliable.

Preferably, a spray device for blowing air to the sink roll surface is provided near the position of the sink roll when the metal strip is bypassed, so that the pickling solution adhered when the sink roll is immersed is sufficiently and quickly. It can be removed and dried. Since air is blown, waste liquid diluted with water does not occur, the pickling solution in the pickling tank does not become thin, and concentration control is easy, which is economical. Further, preferably, the pickling solution receiver is formed in a generally shallow boat shape or gutter shape, is longer than the plate width of the metal strip, and is inclined so that the central portion of the bottom surface is higher than both end portions. Since it is provided with holes at both ends, the pickling solution that has fallen into the pickling solution receiver can be returned directly to the pickling tank without adhering to the metal strip. The rate of reduction of the pickling solution in the pickling tank becomes slow, and the amount and frequency of replenishing the pickling solution can be reduced. Therefore, the proportional cost of the pickling solution is reduced.

Further, preferably, the pickling solution receiver is hung on or near the sink roll, and is kept in a state of floating on the surface of the pickling solution or not soaked away from the surface when the metal strip is immersed. Therefore, in the pickling step, when the sink roll presses the metal strip into the pickling solution and immerses it in the pickling solution, the pickling solution receiver does not become an obstacle, and the pickling step and the bypass step are easily switched. This enables the pickling treatment of metal strips having various pickling conditions on the same production line.

[Brief description of drawings]

FIG. 1 is a front view of a pickling apparatus according to an embodiment of the present invention.

FIG. 2 is a front view of a pickling solution receiver 3 used in the embodiment of FIG.

FIG. 3 is a side view of a pickling apparatus according to an embodiment of the present invention in which a moving device 10 for the pickling solution receiver 3 shown in FIG. 1 is omitted.

FIG. 4 is a perspective view of a pickling apparatus according to an embodiment of the present invention.

FIG. 5 is a configuration diagram of a pickling apparatus using a first conventional technique.

FIG. 6 is a configuration diagram of a pickling apparatus using a second conventional technique.

[Explanation of symbols]

 1 sink roll 1a roll neck part of sink roll 1b bearing of sink roll 2 metal band 3 pickling solution receiver 4 hanging string 5 pickling tank 6 pickling solution 7, 9 spray device 8 hole 10 transfer device for pickling solution 10a moving string

Claims (5)

[Claims] 1. A metal strip can be immersed in a pickling bath for removing an oxide layer from the surface of a metal strip that is continuously threaded, or the metal strip can be pulled up from the pickling bath and bypassed. A pickling device for a metal strip having a sink roll, comprising a pickling solution receiver inserted between the sink roll and the metal strip when the metal strip is bypassed. 2. The pickling device for a metal strip according to claim 1, wherein a spray device for blowing air onto the surface of the sink roll is provided near the position of the sink roll when the metal strip is bypassed. 3. The pickling solution receiver is formed into a generally shallow boat shape or gutter shape, and is longer than the plate width of the metal strip.
The pickling apparatus for a metal strip according to claim 1 or 2, wherein the center portion of the bottom surface is provided with an inclination so as to be higher than both end portions, and holes are provided at both end portions. 4. The pickling solution receiver is hung on both roll necks of the sink roll or in the vicinity thereof, and is moved away from directly under the sink roll when the metal strip is immersed, so that the pickling solution surface is The acid of the metal strip according to any one of claims 1 to 3, characterized in that it is held in a floating state or is held in a state of being separated from the surface of the pickling solution. Washing equipment. 5. The metal strip according to claim 1, 3 or 4, wherein a spray device for blowing air to the back surface of the pickling liquid receiver is provided in the vicinity of the pickling liquid receiver when the metal band is bypassed. Pickling equipment.