KR100470051B1 - apparatus for removing rust on surface of strip - Google Patents

Abstract

The present invention is to remove the oxide film (RUST) of the steel plate welding portion generated during the furnace operation before the welding operation to anneal heat treatment of the cold-rolled coil manufactured in the cold rolling mill of the steel mill to improve the weldability and to perform continuous annealing work and electroplating work An apparatus for removing an oxide film on an improved surface of a steel sheet, the movable technique (12) being reciprocated in the width direction of the steel sheet by a first motor (15) between fixed beams (11a) (11b) provided on the left and right sides of the steel sheet. The moving tech 12 includes a main body 10 having upper and lower moving blocks 19a and 19b which are reciprocated to move toward or away from the upper and lower surfaces of the steel plate by the second motor 16; The upper and lower moving blocks 19a and 19b are provided with upper and lower first pads 21a and 21b for absorbing the washing liquid of the washing liquid container 25, and the upper and lower moving blocks 19a and 19b. On one side of the upper and lower second pads (22a, 22b) for cleaning the foreign matter attached to the upper and lower surfaces of the cleaning operation is completed, the removal unit for removing the oxide film; And detecting the tip of the steel plate and detecting the horizontal movement of the moving deck 12 and the shank movement of the upper and lower moving blocks 19a and 19b to drive the first and second motors 15 and 16. It provides an oxide film removing device of the surface of the steel sheet including a control unit 30 for controlling the.

Description

Apparatus for removing rust on surface of strips

The present invention relates to an apparatus for removing an oxide film on the surface of the steel sheet before welding the steel sheet, and more particularly, to weld the oxide film (RUST) of the steel plate weld portion generated during the furnace operation to heat-treat the cold-rolled coil manufactured in the cold rolling mill of the steel mill The present invention relates to a device for removing oxide film on the surface of a steel sheet which has been removed before work to improve weldability, and to perform continuous annealing and pretreatment.

In general, look at the causes of the oxide film generated on the surface of the steel sheet as follows.

It can be divided into the case where oxygen is supplied and oxidized in the furnace and the case where oxygen and foreign matter are mixed in the atmosphere gas. Ship it.

In particular, the oxide film affects the biggest problem among the factors that lower the weldability. The reason is that the steel sheet is welded by using the melting point of the steel sheet and the steel sheet after inputting a strong current by overlapping the steel sheet without using the electrode due to the core welding characteristics. Because it is made of an oxide film is not welded properly.

Hydrochloric acid is mainly used as a cleaning liquid for removing the oxide film from the surface of the steel sheet. In a conventional cold rolling mill, as shown in FIG. 1, the coil steel sheet enters the side clamp 120 and the upper and lower clamps 121 are used. When it is fixed to the 122, the operator 105 climbs on the guide table 100 installed at the tip of the steel plate welder 140 using the stairs 152, and then the hydrochloric acid container 53 on the jig 151 such as a mop. Wet the hydrochloric acid solution of the) to wash the welds of the front and rear of the steel sheet and then the steel sheet welding operation was performed in the steel sheet welder (140).

In FIG. 1, reference numeral 110 is a guide table, 111, 112, and 113 are idle rolls for guiding the steel plate, and 130 is an exit clamp.

Since the cleaning process must be performed manually before the steel plate welding operation by the conventional method as described above, the normal line operation is difficult, and the situation is acting as a cause that may cause a safety accident.

If the plate break occurs due to poor welding, the product cannot be used at all, and the plate break recovery work takes a lot of time, thereby reducing the work productivity.

Accordingly, the present invention has been made in view of the above-mentioned conventional problems, and its object is to safely and simply remove the oxide film generated at the steel plate welding portion before the welding and connecting the steel plate, thereby improving the steel plate weldability and work productivity. It is an object of the present invention to provide an oxide film removing device on a surface of a steel sheet.

1 is a schematic view showing an oxide film removing operation according to the prior art,

2 is an overall perspective view showing an oxide film removing apparatus of the surface of the steel sheet according to the present invention,

Figure 3 is a perspective view showing the main body portion, the removal portion employed in the oxide film removal apparatus of the surface of the steel sheet according to the present invention,

Figure 4 (a) (b) is a perspective view showing a vertical screw and the connecting bar employed in the oxide film removal apparatus of the steel plate surface according to the present invention,

Figure 5 (a) (b) is an operating state diagram showing the removal portion employed in the oxide film removal apparatus of the surface of the steel sheet according to the present invention,

Figure 6 (a) (b) is a working state in which the cleaning liquid is added in the oxide film removal apparatus of the surface of the steel sheet according to the present invention,

Figure 7 (a) (b) is a perspective view showing the standby and operation start state of the oxide film removing device of the surface of the steel sheet according to the present invention,

Figure 8 (a) (b) is a cross-sectional view showing the operation preparation step in the oxide film removing apparatus of the surface of the steel sheet according to the present invention,

9 is a cross-sectional view showing the standby state after the addition of the cleaning liquid in the oxide film removing apparatus of the surface of the steel sheet according to the present invention,

10 is a cross-sectional view showing an operation state of applying a cleaning liquid to the steel sheet in the oxide film removing device of the surface of the steel sheet according to the present invention;

11 is a cross-sectional view showing a working state of the final cleaning of the steel sheet in the oxide film removing device of the surface of the steel sheet according to the present invention.

Explanation of symbols on the main parts of the drawings

11a 11b ... fixed beam 12 .... moving deck

13 .... Horizontal Guide Bar 14 .... Horizontal Screw

15 .... 1st motor 16 .... 2nd motor

19a, 19b ... upper and lower moving blocks 21a, 21b .... upper and lower first pad

22a, 22b .... upper and lower second pads 23a, 23b .... spring member

25 .... Cleaning solution container 26 .... Piping member

31 .... Sensor for detecting steel plate 32 .... First sensor

33 .... second sensor 34 .... third sensor

As a technical configuration for achieving the above object, the present invention,

In the apparatus for removing the oxide film generated on the steel sheet tip surface at the inlet side of the steel sheet welder,

Between the fixed beams provided on the left and right sides of the steel plate is provided with a moving tech reciprocating in the width direction of the steel plate by the first motor, the moving tech reciprocating to move closer or away from the upper and lower surface side of the steel plate by the second motor A main body part having upper and lower moving blocks;

The upper and lower moving blocks are provided with upper and lower first pads for absorbing the washing liquid of the washing liquid container, and one side of the upper and lower moving blocks washes foreign substances attached to the upper and lower surfaces of the steel sheet after the washing operation is completed. A removal unit having upper and lower second pads to remove the oxide film; And

A steel plate detecting sensor is provided on an auxiliary table hinged by a cylinder member when detecting the tip of the steel plate, and the first fixed beam includes a first sensor for detecting one end of the moving deck, and the moving deck has a first sensor. And a second sensor for sensing the highest position, and having a third sensor for detecting one end of the steel plate on one side of the upper moving block, and a fourth for detecting the close contact with each other by pinching operation on the upper and lower moving blocks. It is equipped with a sensor and a plate, and one side of the upper second pad is provided with a fifth sensor for sensing one end of the steel plate, while the upper side connection bar has a limit switch for stopping the opening operation when in contact with the upper surface of the upper movable block The front end of the steel plate and the moving deck, the upper and lower moving blocks to detect the horizontal movement of the moving deck and the upper and lower The oxide film removal apparatus of the steel sheet surface, characterized in that it comprises a control unit for controlling the driving of the first and second motors so as to restrict the vertical movement of the block of the by maryeonham.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

2 is an overall perspective view showing an oxide film removing device of the surface of the steel sheet according to the present invention, Figure 3 is a perspective view showing the main body portion, the removal portion employed in the oxide film removing device of the steel plate surface according to the present invention, Figure 4 (a (b) is a perspective view showing a vertical screw and a connecting bar employed in the oxide film removing apparatus of the steel sheet surface according to the present invention.

The apparatus 1 of the present invention is disposed on one side between the steel plate welder 140 for welding the steel plate and the entrance clamp frame 120 for mounting the steel plate to remove the oxide film generated on the upper and lower surfaces of the steel plate tip. As such, the apparatus 1 includes a main body 10, a removal unit 20, and a control unit 30.

That is, the main body 10 is fixed to the fixed beam (11a) (11b) vertically installed on the left and right sides of the traveling line of the steel plate, respectively, and the horizontal guide bar (assembled between the fixed beam (11a) (11b) ( 13) and the horizontal screw 14 is provided with a moving deck 12 reciprocating in the width direction of the steel sheet by a drive source of the first motor 15 for rotating the horizontal screw 14 in the forward and reverse directions do. At this time, the bearing block 14a is mounted on both left and right ends of the horizontal screw 14, respectively.

In addition, the second guide 16 is fixedly installed on the 'c' shaped frame 12a integrally formed thereon so as to move horizontally with the movable deck 12, and vertical guides are assembled perpendicular to the frame 12a. The bar 17 and the vertical screw 18 have upper and lower movable blocks which are moved in contact with or away from the steel plate surface by a driving source of the second motor 16 which rotates the vertical screw 18 in the forward and reverse directions. Each of (19a) and (19b) is provided and configured.

Here, the vertical screw 18, as shown in Figure 4, the upper and lower movable blocks 19a, 19b disposed on the upper, lower sides of the steel sheet to open and pinch operation so that the upper movable block It consists of a right-hand screw (18a) is assembled (19a) and a left-hand screw (18b) is assembled to the lower movable block (19b), the screw member (18a) (18b) via the fixing key (18c). The upper end of the shaft 18d to be assembled is assembled with a drive gear 16a assembled to the drive shaft of the second motor 16 and a driven gear 18e geared to the lower end, and a bearing block 18f is assembled at the bottom. In the middle of the length, the guide roller 18i driven in contact with the tip of the steel sheet during the washing operation is assembled. In addition, the middle of the length of the vertical guide bar 17 is provided with a guide roller 17a which is in contact with the tip of the steel plate to be driven.

In Fig. 4, reference numeral 18g is a spacer, and 18h is a bearing member.

In addition, a plurality of lower rollers 41a are idlely driven on the lower surface of the upper moving block 19a, and a plurality of lower rollers 41b are idlely driven on the upper surface of the lower moving block 19b. do.

In addition, the removal unit 20 for removing the oxide film of the welding portion to improve the weldability of the steel sheet is supplied to the washing liquid filled in the washing liquid container 25 is installed on the upper moving block (19a) to absorb the image, Each of the lower first pads 21a and 21b is provided, and on one side of the first pads 21a and 21b to clean the cleaning liquid and foreign substances on the steel plate and the lower surface of the steel sheet after the cleaning operation is completed. Upper and lower second pads 22a and 22b are provided and configured, respectively.

Here, the upper and lower first pads 21a and 21b vertically penetrate the upper and lower movable blocks 19a and 19b and are elastically supported by spring members 23a and 23b. It is mounted so as to be replaceable by fixing frames 21c and 21d mounted at one end of the tension bars 24a and 24b, and the upper and lower second pads 22a and 22b are on one side of the upper and lower tension bars. Each hooking jaw 24 and one end of the 24a and 24b are detachably attached to the 'a' shaped connecting bars 22c and 22d which are integrally connected.

The 'a' shaped connecting bar (22c) (22d) is, as shown in Figure 4 (b), the gap adjusting nut, bolts 51, 52 are assembled to adjust the vertical length in the middle of the length, the top The fixing bar 53 is detachably connected to the upper and lower tension bars 24a and 24b, and a pad block at which the upper and lower second pads 22a and 22b are detachably assembled to the upper and lower tension bars 24a and 24b. 54 is assembled by the fixing pin 54a.

And, the washing liquid container 25 is installed perpendicular to the fixed bar (25a) is fixed to the upper surface of the upper moving block (19a), the hollow pipe member 26 into the lower inlet of the washing liquid container (25). ) Is inserted, and the pipe member 26 mounts a conical orifice 26a at the upper end, and forms an injection hole 26b through which the cleaning liquid flows into the upper outer circumferential surface, and the upper surface of the upper first pad 21a. While the lower end is in contact with the guide hole 19 of the upper moving block (19a) is assembled so as to be movable, while the inlet portion of the cleaning solution container 25, the O-ring to prevent leakage of the cleaning solution, such as hydrochloric acid ( 25b).

On the other hand, the control unit 30 detects the steel plate front end, the horizontal reciprocating movement of the moving deck 12, the upper and lower movement blocks 19a, 19b and the upper and lower reciprocating movements at the same time to control the amount of movement As the steel plate detecting sensor 31 for operating the upper and lower clamps 121 and 122 of the side clamp 120 to detect the front end of the steel sheet and fix the tip of the steel plate can be hinged at the front end of the guide table 100. It is provided in the auxiliary table 101 to be assembled, the auxiliary table 101 is assembled to the cylinder member (31a) so that the movable deck 12 can move horizontally reciprocating without interference.

The fixed beam 11a is provided with a first sensor 32 that senses one end of the movable deck 12 to control horizontal reciprocating movement, and on the inner surface of the frame 12a of the movable deck 12. A second sensor 33 which detects the highest position of the upwardly moved upper moving block 19a to stop the opening operation, and a third sensor that detects one end of the steel plate on one side of the upper movable block 19a; 34), the upper and lower moving blocks (19a) (19b) is provided with a fourth sensor (35a) and a plate (35b) for detecting the close contact with each other by the pinch operation, the upper second pad (22a) One end of the limit switch 37 is provided with a fifth sensor 36 for sensing one end of the steel plate, while the upper side connecting bar 22c stops the opening operation when contacting the upper surface of the upper moving block 19a. Equipped with.

The operation and effects of the present invention as described above will be described.

Figure 5 (a) (b) is an operating state diagram showing the removal portion employed in the oxide film removing device of the steel plate surface according to the present invention, Figure 6 (a) (b) is an oxide film removing device of the steel plate surface according to the present invention Figure 7 (a) (b) is a perspective view showing the standby state and the operation start state of the oxide film removing device of the surface of the steel sheet according to the present invention, Figure 8 (a) (b) is a present invention FIG. 9 is a cross-sectional view illustrating an operation preparation step in an oxide film removing device of a steel plate surface according to the present invention, FIG. 9 is a cross-sectional view showing a standby state after adding a cleaning solution to the oxide film removing device of a steel plate surface according to the present invention, and FIG. FIG. 11 is a cross-sectional view showing a working state of applying a cleaning liquid to a steel sheet in the oxide film removing apparatus of the steel plate surface according to the present invention, and FIG. 11 is a cross-sectional view showing a working state of final cleaning of the steel sheet in the oxide film removing apparatus of the steel plate surface according to the present invention.

First, in the normal steel plate advancement and operation standby, the apparatus 1 of the present invention waits to one side so as not to interfere with the steel plate advancement line, and when an oxide film is generated at the tip of the steel plate to be welded to remove it, The operator turns on the steel plate detecting sensor 31 of the auxiliary table 101 by pressing the first switch of the control panel 160 before the steel sheet enters the entrance clamp 120.

In this state, when the steel sheet passing between the upper and lower clamps 121 and 122 of the entrance clamp 120 is detected by the steel sheet detecting sensor 31, the auxiliary table 101 of the auxiliary table 101 is detected by the detection signal. By the reverse operation of the cylinder member 31 assembled at the lower end side, the auxiliary table 101 is pivoted downward to finish the work of the first section, which is the work preparation section.

Subsequently, when the operator presses the second switch of the control panel 160, as shown in Fig. 9 (a), the second screw 16 is rotated in the forward direction, the driving force is raised, the screw screw 18a ( The upper and lower moving blocks 19a and 19b, which are delivered to the vertical screw 18 and assembled to the vertical screw 18, are retracted inward, and the upper and lower first pads 21a and 21b are assembled to each other. Surface contact starts, and the driving of the second motor 16 is continued until the fourth sensor 35a of the upper moving block 19a is sensed by the plate 35b.

In this case, the orifice 26a at the upper end is inserted into the washing liquid container 25, and the hollow tubular member 26 whose lower end is in contact with the upper first pad 21a is the spring member of the upper tension bar 24a. Since the injection port 26b formed on the upper outer surface of the pipe member 26 by being raised by the upper first pad 21 which is raised while compressing the 23a enters into the washing liquid container 25, the washing liquid is It is injected into the injection port 26b and discharged through the piping member 26 to sufficiently wet the upper first pad 21a and the lower first pad 21b which is in contact with the lower surface thereof.

At this time, a hydrochloric acid solution, which is a washing solution of the washing liquid container 25, is injected into the upper and lower first pads 21a and 12b to control a driving state of the second motor 16. It can be determined by, and also, the operator can determine the input amount of the washing liquid through the scale formed on the outer surface of the washing liquid container 25.

Then, when the washing liquid input operation is completed, the second motor 16 is reversely rotated in contrast to the above after a predetermined time, the vertical screw 18, the vertical guide bar 17, the upper and lower movement The blocks 19a and 19b are moved apart to the neutral position, and the neutral positioning is performed by the second sensor 33 mounted to the rear of the upper moving block 19a, and by the detection signal. The reverse rotation driving of the second motor 16 is stopped.

At this time, the second section work to bury the cleaning liquid on the upper and lower first pads (21a) (21b) is possible even during line operation, so may be performed from time to time to reduce the working time, the upper, lower moving block (19a) The opened neutral position of 19b adjusts the height of the second sensor 33 so that the upper and lower second pads 22a and 22b which are operated in reverse are not in surface contact with each other.

In addition, when the second section operation as described above is finished, as shown in Figs. 10 and 11, the operator presses the third switch of the control panel 160 to drive the first motor 15 in the forward rotation to the horizontal screw When the 14 is rotated forward, the moving deck 12 assembled therein is gradually moved from the left to the right in the drawing, and the third sensor 34 of the upper moving block 19a that is moved together with the moving deck 12. ) Detects one end of the steel plate to perform the oxide film removal operation, the rotational drive of the first motor 15 is temporarily stopped by the detection signal.

At the same time, the second motor 16 is driven to rotate in the forward direction, and the upper and lower moving blocks 19a and 19b are pinched and operated from the neutral position to the working position, and the fourth sensor 35a is detected by the plate 35b. The rotational operation of the second motor 16 is continued until the upper and lower first pads 21a and 21b assembled at the upper and lower moving blocks 19a and 19b are welded at the tip of the steel sheet. Is to be in close contact.

When the upper and lower surfaces of the welded portion of the steel sheet are in close contact with each other as the upper and lower first pads 21a and 21b, the first motor 15 is re-driven in the forward direction so that the movable deck 12 moves from the left side. When moved back to the right side, the steel plate front end is washed by the upper and lower first pads 21a and 21b in which the washing liquid is applied. In addition, when the third sensor 34 of the upper moving block 19a that continues to move with the moving deck 12 senses the other end of the steel plate, the rotation driving of the first motor 15 is stopped. .

At this time, when the upper and lower moving blocks (19a, 19b) is in close contact with the upper and lower surfaces of the steel sheet, the upper and lower rollers (41a) (41b) assembled to the block members (19a) (19b) The collection tank is in contact with the steel sheet to prevent pinching, preventing falling off, and the washing liquid flowing down to the lower part during the steel sheet washing operation is connected to the collection tank connected to this through the drain pipe 44 installed in the receiving groove 19d of the lower moving block 19b. Whole quantity is collected at (45).

In addition, the fourth section operation of removing the cleaning liquid and foreign matter remaining on the steel plate welded portion where the oxide film has been cleaned as the cleaning liquid is carried out by the operator of the control panel 160 while the moving deck 12 is completed at the right end of the drawing. When the fourth switch is pressed, since the first motor 15 is rotated in the opposite direction to the above, the movable deck 12 starts to move horizontally from right to left, and at this time, the upper deck 22a is installed on the upper second pad 22a. The other end of the steel plate is detected by the fifth sensor 36, and the reverse rotation driving of the first motor 15 is stopped by the detection signal.

If the gap between the upper and lower moving blocks 19a and 19b that are continuously closed by the second motor 16 is rotated in the reverse direction while the moving deck 12 is stopped continuously, the upper The upper and lower movable blocks 19a and 19b are formed by elastic restoring force of the spring members 23a and 23b of the upper and lower tension bars 24a and 24b assembled to the lower movable blocks 19a and 19b. Since the upper and lower first pads 21a and 21b, which are accommodated in the respective accommodation grooves 19c and 19d of the reinforcement, are elastically supported to the upper and lower surface sides of the steel plate, the one upper and lower tension bars 24a ( The connecting bars 22c and 22d connected to 24b are closed inward, and the steel plate is closely adhered between the upper and lower second pads 22a and 22b assembled at each end of the connecting bars 22c and 22d. Let's go. In addition, when the limit switch 37 of the upper connection bar 22c moving to the upper moving block 19a contacts the upper surface of the upper moving block 19a and detects a steel sheet contact state, a detection signal generated at this time is generated. By this, the reverse rotation driving of the second motor 16 is stopped.

In succession, the upper and lower first pads 21a and 21b are spaced apart from the upper and lower surfaces of the steel sheet, while the upper and lower second pads 22a and 22b are in close contact with the upper and lower surfaces of the steel sheet. In the retracted state, when the second motor 16 is re-driven in the reverse direction and the moving deck 12 is moved from right to left again, the upper and lower second pads 22a and 22b are used to weld the steel plate. Residual wash solution and foreign matter will be removed.

In this case, the upper and lower second pads 22a and 22b, in which wear occurs more severely than the upper and lower first pads 21a and 21b, are gap adjusting nuts installed on the connection bars 22c and 22d, By adjusting the length by the bolts (51) (52) can compensate for the degree of wear, it is possible to quickly replace the excessively worn pad member because it is easy to remove.

When the right end of the movable deck 12 that is horizontally moved in the reverse direction is detected by the first sensor 32 installed at the upper end of the fixed beam 11a, the first motor 15 is reversed by the detection signal. The rotation drive is stopped, and all the oxide film removing operations for the steel plate welding portion are completed. At this time, the moving deck 12 is stopped at the initial position of one side away from the steel sheet progress line.

In addition, the cylinder member 31a connected to the auxiliary table 101 is moved forward by the detection signal of the first sensor 32, and the auxiliary table 101 is arranged to be parallel to the guide table 100. After operating the clamp cylinder 123 to raise the upper clamp 121 of the entrance clamp 120, the steel sheet is moved forward to the steel plate welder 140 to perform the steel sheet welding operation.

According to the present invention having the above-described configuration, the operation of removing the oxide film generated on the surface of the steel sheet from the inlet side of the steel sheet welder before the steel sheet welding operation is performed by a simple switch and handle operation without the use of a squeeze or a mop as a worker. Since it can be carried out to improve the weldability of the steel sheet to prevent plate breakage accident, improve the work productivity, and the effect of preventing safety accidents due to the use of the cleaning solution, such as hydrochloric acid solution is obtained.

While the invention has been shown and described with respect to specific embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit or scope of the invention as set forth in the claims below. I would like to clarify that knowledge is easy to know.

Claims (5)

In the device for removing the oxide film generated on the steel sheet tip surface at the inlet side of the steel plate welder 140, Between the fixed beams (11a) (11b) provided on the left and right sides of the steel sheet is provided with a moving tech 12 reciprocating in the width direction of the steel sheet by the first motor 15, the mobile tech 12 is A main body portion (10) having upper and lower moving blocks (19a) and (19b) reciprocated to move toward or away from the steel plate upper and lower surface sides by two motors (16); The upper and lower moving blocks 19a and 19b are provided with upper and lower first pads 21a and 21b for absorbing the washing liquid of the washing liquid container 25, and the upper and lower moving blocks 19a and 19b. One side of the removal unit 20 is provided with upper and lower second pads (22a) (22b) for cleaning the foreign matter attached to the upper, lower surface of the steel plate, the cleaning operation is completed; And The steel plate detecting sensor 31 is provided on the auxiliary table 101 hinged by the cylinder member 31a to detect the end of the steel plate, and the one side of the fixed beam 11a detects one end of the moving deck 12. It is equipped with a first sensor 32, the moving deck 12 is provided with a second sensor 33 for detecting the highest position of the upper moving block (19a), one side of the upper moving block (19a) of the steel plate It is provided with a third sensor 34 for detecting one end, and the upper and lower moving blocks (19a, 19b) is provided with a fourth sensor (35a) and a plate (35b) for detecting the close contact with each other by pinch operation. On one side of the upper second pad (22a) is provided with a fifth sensor (36) for detecting one end of the steel plate, while the upper side connecting bar (22c) is open when in contact with the upper surface of the upper moving block (19a) It is equipped with a limit switch 37 to stop the operation to detect the end of the steel plate, the moving deck 12, the top, The first and second motors 15 detect the secondary moving blocks 19a and 19b to limit the horizontal movement of the moving deck 12 and the vertical movement of the upper and lower moving blocks 19a and 19b. An oxide film removing apparatus for the surface of a steel sheet, characterized in that it comprises a control unit (30) for controlling the driving of (16). The method of claim 1, The vertical screw 18 to which the upper and lower movable blocks 19a and 19b are assembled is composed of a right screw 18a and a left screw 18b, and is assembled to a drive shaft of the second motor 16 and has a length. An oxide film removing device for a surface of a steel sheet, characterized in that the guide roller (18i) is driven in contact with the tip of the steel sheet in the middle. The method of claim 1, The removal unit 20 is the upper and lower tension bar is elastically supported by the spring member (23a, 23b) disposed in the receiving groove (19c) (19d) of the upper, lower moving block (19a) (19b) ( The upper and lower first pads 21a and 21b detachably assembled at the lower ends of the 24a and 24b, and one end of each of the upper and lower engaging bars 24a and 24b of the upper and lower first pads 21a and 21b are connected. Conical orifice 26a at the top of the upper and lower second pads 22a and 22b that are detachably assembled to the 'A' shaped connecting bars 22c and 22d and the lower inlet of the cleaning liquid container 25. Is inserted, and the injection hole 26b is formed in the upper outer peripheral surface, and the oxide film is removed from the surface of the steel sheet, characterized in that the upper end of the upper first pad 21a is provided with a piping member 26 in contact with the lower end. Device. 4. The oxide film on the surface of the steel sheet according to claim 3, wherein the 'a' shaped connecting bars 22c and 22d are assembled with gap adjusting nuts and bolts 51 and 52 so as to adjust the vertical length between the lengths. Removal device. delete