JP2818688B2 - Method for preventing magnetization of winding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial applications]

The present invention relates to a method of preventing magnetization of a winding device, and more particularly to a method of preventing magnetization of a winding device suitable for use in winding a metal strip on a winding device in a metal strip electrolytic treatment line.

[Prior art]

In a line for electrolytically treating a metal strip, for example, a line having an electrolytic pickling tank and an electrolytic pickling treatment of a steel strip in the treatment tank, the steel strip after the pickling treatment is usually transferred to the next line. It is wound on a winding device (for example, a winding reel). Generally, in the processing line, an insulating roll such as a rubber roll is used as a roll used in each part of the line from the viewpoints of leakage current prevention and flaw prevention. The method of winding the steel strip around the winding device includes a method of inserting the tip of the steel strip into a grip portion of the winding device and a method of winding the steel strip using a belt wrapper. The former method is used when the steel strip is thick and the processing speed is low. The latter method is a method in which a sleeve such as rubber is mounted on the winding device in advance, and the steel strip is wound on the sleeve using a belt wrapper. Used when fast. When performing electrolytic pickling or electrolytic degreasing on a steel strip in an electrolytic treatment line, in general, current is locally applied to the steel strip because stainless steel strip is indirectly energized and the electrodes and steel strip are not grounded. A potential is generated. Since the steel strip is a low-resistance conductor, it has electrical continuity with the roll in the line or with the winding device (particularly by inserting the steel strip tip into the grip) or the rewinding device, and is electrically looped. If it is possible, current will flow. For example, even if the in-line roll is formed of an insulating roll, an electric loop is formed and a current flows if the winding roll is not insulated from the ground. Conventionally, no means has been taken to positively prevent current from flowing through the loop as described above. In addition, regarding the winding, in order to prevent co-shifting flaws (crimping flaws) that occur when the steel strips come into contact with each other during the winding of the stainless steel strip and a slight shift occurs, the winding layer of the steel strip is used. Is filled with interleaf paper such as kraft paper. Since the slip sheet is inserted, the wound steel strip is electrically insulated between the winding layers, and becomes just like an electromagnetic coil. Therefore,
When a current flows through the steel strip and a current flows through the wound coil-shaped steel strip winding layer, the winding layer becomes an electromagnet. Moreover, the material of the reel of the winding device differs depending on the member, but is usually a magnetic material whose main part is formed of high Cr steel. Therefore, after being magnetized as described above,
Even after the current in the steel strip stops flowing and the action of the electromagnet is reduced, magnetism remains in the winding device (residual magnetism is generated), resulting in a permanent magnet.

[Problems to be solved by the invention]

When the winding device is magnetized as described above, there are the following problems. For example, as shown in FIG. 5, when the steel strip (metal strip) 3 after the electrolytic treatment is transported and wound on a take-up reel (winding device) 1, first, the tip of the steel strip 3 is moved to, for example, a sixth strip. As shown in the drawing, the reel is inserted into a grip portion (grip groove) 2 of the take-up reel 1 and wound. When the take-up reel 1 is a permanent magnet having a polarity as shown in FIG. 6 for example, when the end of the steel strip 3 is brought close to the take-up reel 1 to be inserted into the grip groove 2, the steel The belt 3 is attracted to the body of the take-up reel 1 by magnetic force before entering the grip groove 2,
It becomes difficult to insert because it is absorbed. Grip groove 2
If the end of the steel strip 3 cannot be inserted into the steel strip 3, the steel strip 3 cannot be wound. In contrast, steel strip 3
When the insertion is failed in order to move forward and insert again, if the line is a continuous line, the loop amount becomes insufficient, and there is a possibility that the line may be stopped. SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and it is intended to prevent the magnetization of a winding device so that a smooth insertion of a strip into a grip groove is possible, and a smooth strip winding and an electrolytic processing line are provided. It is an object of the present invention to provide a method for preventing magnetization of a winding device which can ensure smooth operation of the winding device.

[Means for Solving the Problems]

The present invention provides, in an electrolytic processing line for a metal strip, an insulating material interposed between the winding device and the ground when the strip is wound on the winding device, thereby insulating the winding device from the ground. This is to solve the above-mentioned problem. Further, in the present invention, in a metal strip electrolytic treatment line, when the strip is wound around a winding device, an earth roll is provided in a metal strip transport path between the electrolytic treatment tank and the winding device, and the earth roll is attached to the ground roll. The above-mentioned problem is also solved by transferring the strip to the ground potential by transferring the strip to ground.

[Action]

In the electrolytic processing line, in order to magnetize a take-up device such as a take-up reel, a magnetic field H (A / A /
m) must be affected. Generally, the magnetic field H (A / m) due to the electromagnetic action of the current I is represented by the following equation. H = n · I [A / m] (1) where n is the number of turns of the electromagnetic coil (= the number of turns [T / m] of the metal strip insulated between layers, I; the current flowing through the electromagnetic coil (= steel strip) The current flowing through the metal strip is [A].
Since a slip sheet is used, an electromagnetic action similar to that of an electromagnetic coil occurs when a current flows through the metal strip winding layer. or,
When performing an electrolytic treatment such as electrolytic pickling, a potential is generated between the metal strip and the ground, and the potential causes a current to flow through an electrical circuit loop from the metal strip and the winding device to the ground. The strip winding layer produces an electromagnetic action according to the equation (1). If this electromagnetic action occurs, the winding device is magnetized by the magnetic field, and remains magnetized by the residual magnetism even after the electrolytic treatment is completed, the strip winding is completed, and the wound strip is extracted. . Due to the residual magnetism, the winding device exhibits the function of a permanent magnet, and the next winding becomes difficult. The reason that the winding device is magnetized is that the current flows through the strip wound on the winding device as described above.
In order to prevent this magnetization, either the number of turns n or the current I in the equation (1) may be eliminated and set to 0 (zero). As a method of setting the number of turns n to 0, a method of not inserting a slip sheet, or a method of loading a conductive sheet instead of a slip sheet can be considered, but any of these methods is technically and cost-effective. There is impossible. For this reason, a method for setting the current I to 0 was studied. Here, FIG. 2 shows an electrolytic pickling line of a metal strip, for example, a steel strip, and an example of the potential distribution thereof. In the electrolytic pickling line shown in FIG. 2, the strip (steel strip) 3 unwound from the pay-off reel POR is first supplied to one or three electrolytic baths 4.
A and 4B are reached. In the electric field tanks 4A and 4B, a current is passed from the positive electrode and the negative electrode to the strip 3 via the electrolytic solution to perform electrolytic pickling treatment. In FIG. 2, reference numerals a to j denote measurement points of the potential between the ground, and the potentials at the respective measurement points are as shown in FIG. In addition,
c, d, g, and h indicate the electrode potentials of the power supply device 4 of the electrolytic cells 4A and 4B. FIG. 3 shows an example of an electric equivalent circuit from the electrolytic baths 4A and 4B of the electrolytic pickling line, the metal strip 3, the winding device 1, and the ground. Code R _N (MΩ) in the third diagram shows the _{resistance, R P, R S1 ~R S3} , R T (MΩ) the interval resistance of the steel strip 3, R
_{L1 to} R _L4 (MΩ) represent the electrolyte resistance of the electrolytic cells 4A and 4B. In the electrolyzers 4A and 4B, an electrolysis power supply device 4 is provided in each of the electrolyzers, and the scale of the surface of the steel strip 3 is descaled in each of the electrolyzers 4A and 4B. The electrolytic power supply device 4 normally performs constant current control. For example, in the case of single-cell electrolysis, a current flowing from the electrode c on the positive electrode side flows through the electrolytic solution into the steel strip 3, passes through the electrolytic solution, and passes through the negative electrode. It returns to the power supply device 4 via the electrode d on the side. This current loop is c → b → e in the equivalent circuit of FIG.
→ Flow in the direction of d, and the resistance between them becomes R _L1 , R _S1 and R _L2 . Since the current flows through the steel strip 3 as described above, each position of the steel strip 3 has a potential. Further, the steel strip 3 may be grounded in the winding device 1 and the rewinding device POR,
As a result, the steel strip 3 is connected at points a and j through the ground to form an electric closed loop circuit. The closed loop circuit in this case is a → b → e → f → i →
j → a. Therefore, since the steel strip of the electrolytic pickling unit has a potential, and a closed loop circuit electrically connected through the steel strip occurs,
An electric current flows through this closed loop to generate a magnetic field in the winding device. In order to cut off such a current flow, the closed loop circuit may be cut off, that is, electrically insulated, or the potential of the metal strip may be set to the ground potential. Therefore, in the present invention, an insulator is interposed between the winding device and the ground to prevent the closed loop circuit from being formed and to interrupt the flow of current to the winding device. As a result, it is possible to prevent a current from flowing through the metal strip wound by the winding device. Further, a grounding earth roll is provided in a strip conveyance path between the electrolytic treatment tank and the winding device, and the ground roll is brought into contact with the strip to bring the strip to the ground potential, so that the current flowing from the metal strip is reduced. To the ground before going to the winding device. As a result, the current flowing from the winding device to the ground can be made almost constant. Therefore, it is possible to almost completely prevent the current from flowing from the metal strip to the winding device, and it is possible to substantially eliminate the occurrence of a magnetic field from the metal strip and the magnetization of the winding device. Therefore, since the leading end of the strip can be smoothly inserted into the grip portion of the winding device and fixed, it is possible to eliminate a defective portion due to a line stop,
The yield can be improved. In addition, when the winding device is magnetized, there is a risk that small steel slabs are adsorbed on the surface of the winding device and indentation flaws are generated by the small steel slab adsorbed. Can be eliminated, and the quality can be improved.

【Example】

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The first embodiment of the present invention relates to a winding system for winding a steel strip 1 as shown in FIG. 1 around a winding reel unit (winding device) 6, wherein an electrical insulation is provided between the system installation unit and the ground. This is a magnetization prevention device for a winding device in which an insulating member 5 made of a material is interposed to prevent the reel unit 6 from being magnetized. As shown in FIG. 1, the winding system includes a reel unit 6 for winding the steel strip 3, a winding motor 8 for rotating and driving the reel unit 6 through a speed reducer 7, and a winding motor 8. It is mainly composed of a center position control device (CPC device) 9 for making the shapes of the cuts uniform. The CPC device 9 is for controlling the winding position of the steel strip 3 by moving the reel unit 6 back and forth in the axial direction thereof,
The reduction gear 7 and the winding motor 8 mounted on the common base 20 are integrally slid by the hydraulic cylinder 9A to move the reel unit 6 back and forth. A sliding mechanism 22 is provided below the common base 20. An insulating member 5 is interposed between the sliding mechanism 22 and a pedestal 24 fixed to the ground, so that the common base 20 and the reel unit 6 are insulated from the ground. Since the voltage applied from the steel strip 3 to the reel unit 6 is low, the insulating member 5 does not need to use a special material, for example, a material having a high withstand voltage.
Sufficient insulation can be provided. The insulating member 5 is made of, for example, a cotton fine thread cloth having excellent moisture resistance and electric characteristics and excellent impact resistance among laminates generally used for printed wiring boards (so-called printed boards). Phenolic resin laminate (thickness
3.0mm) can be used. If this phenolic resin laminate is used, its insulation resistance is 10 ⁴ to 10 ⁶ (MΩ), so that the insulation properties are good and the current flowing from the reel section 6 to the ground can be completely cut off. In the winding system, the reel member 6 on the common base 20 and the ground can be completely insulated by the insulating member 5. Therefore, since no current flows from the steel plate 3 to the reel portion 6, the reel portion 6 is not magnetized, and the steel strip 3 is smoothly inserted into the grip groove 2 of the reel portion 6 to perform the winding operation reliably. obtain. Next, a second embodiment will be described. In this second embodiment, as shown in FIG. 4, an anti-magnetization device of a winding device in which an earth roll 10 made of, for example, carbon is rolled and brought into contact with a steel strip 3 before being wound by a winding system. It is. Note that the winding system can be implemented for the first embodiment in which the insulating member 5 is not interposed or other known winding systems, and illustration and description of the system configuration are omitted. The earth roll 10 shown in FIG.
And a brush (electric brush) 12 for slidingly contacting the collector ring 11 and flowing the current of the collector ring 11 to the ground. The brush 12 and the ground are electrically connected by a cable, and the earth roll 10 is at the ground potential. A deflector roll 13 is provided on the opposite side of the earth roll 10 with the steel strip 3 interposed therebetween. Thus, the steel strip is pinched by the earth roll 10 and the deflector roll 13, and the rolling force is appropriately adjusted by springs 14 provided at both ends of the shaft of the earth roll 10. The earth roll 10 is conductive and has a steel strip 3.
It is preferable to use a material that is softly rolled to the surface, and for example, a material made of carbon or metallic carbon can be used. In the second embodiment, if there is no earth roll 10, most of the current flowing from the electrode of the electrolytic cell to the earth via the steel strip 3 and the winding device 6 will flow through the earth roll 10. . Therefore, in the second embodiment, the current flowing through the take-up reel section 6 can be suppressed to about 1/10 or less as compared with the related art, and the state of magnetization of the reel section 6 can be prevented to a degree that does not cause a problem in operation. In the first embodiment, an insulator is interposed in the sliding mechanism 22 of the winding device in a configuration as shown in FIG.
In the embodiment, the magnetization of the winding device is prevented by grounding the steel strip to the ground by the earth roll 10 having the structure shown in FIG. 4, but the magnetization preventing device according to the present invention is as shown in FIG. The present invention is not limited to this, and the present invention can be implemented in other various aspects. The present invention is not limited to insulating the entire winding device from the ground as in the first embodiment, but an insulator can be interposed on the shaft of the reel unit so as to insulate only the reel unit. Further, the present invention is not limited to grounding the metal strip with one ground roll as in the second embodiment, but a plurality of ground rolls can be transferred to the strip in parallel to ground.
By doing so, the contact resistance can be relatively low,
The ground current can be reliably sent to the ground.

【The invention's effect】

As described above, according to the present invention, since the magnetization of the winding device can be reliably prevented, the insertion and attachment of the leading end of the strip to the winding device can be performed smoothly. Therefore, various problems caused by the magnetized winding device, for example, a problem such as a line stop caused by the inability of the strip tip to be smoothly inserted into the grip portion of the winding device, do not occur at all. Poor quality portions can be eliminated, and thus the yield can be improved. In addition, since the reel of the take-up device is magnetized, an excellent effect is obtained such that the indentation flaw generated by the adsorption of the minute steel slab on the reel surface can be surely reduced or eliminated.

[Brief description of the drawings]

FIG. 1 is a side view showing the entire configuration of a winding device provided with a magnetization prevention device according to a first embodiment of the present invention, and FIG. 2 is an electrolytic pickling for explaining the principle of the present invention. FIG. 3 is a circuit diagram showing an example of an electrical equivalent circuit of the pickling line, and FIG. 4 is a circuit diagram showing an example of an electric equivalent circuit of the pickling line. FIG. 5 is a side view showing a configuration example of a conventional winding device, and FIG. 6 is a perspective view showing a configuration example of a take-up reel unit. 3 ... steel strip (metal strip), 4A, 4B ... electrolytic cell, 4 ... electrolytic power supply device, 5 ... insulating member, 6 ... reel part (winding device), 7 ... reduction gear, 8 ... … Winding motor, 9… CPC device, 9A …… hydraulic cylinder, 10 …… ground roll, 11 …… collector ring, 12 …… brush, 13 …… deflector roll, 20 …… common base, 22 …… sliding Dynamic mechanism.

Claims (2)

(57) [Claims] 1. In a metal strip electrolytic treatment line, when winding the strip on a winding device, an insulator is interposed between the winding device and the ground to insulate the winding device from the ground. A method for preventing magnetization of a winding device. 2. In a metal strip electrolytic treatment line, a grounding earth roll is provided in a metal strip transport path between an electrolytic treatment tank and a winding device when the strip is wound around a winding device. A method for preventing magnetization of a winding device, wherein a roll is transferred to the strip to set the strip to a ground potential.