JP3443305B2 - Apparatus for preventing meandering of steel sheet and method for preventing meandering of steel sheet using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel plate meandering preventing device and a steel plate meandering preventing method using the same. More specifically, the present invention relates to a meandering preventive device capable of improving the centering force of a steel plate with a small number of rolls and a method of preventing meandering of a steel plate using the same.

[0002]

2. Description of the Related Art Conventionally, in a continuous annealing furnace or the like, a strip-shaped steel sheet which is continuously passed is carried while being supported by a plurality of sets of rolls. Further, in order to prevent the meandering of the steel sheet conveyed along a predetermined route, various kinds of meandering preventing devices have been conventionally used.

The meandering preventive device 31 shown in FIG. 11 has an inverted V-shape so as to move downstream from the center line C of a predetermined path in the width direction of the steel sheet S in the conveying direction D of the steel sheet S. Multiple sets of rolls 32 arranged at an angle
And a stage 33 that rotatably supports the roll 32.
It consists of and. The meandering prevention device 31 provided with the rolls 32 arranged in the inverted C-shape is often used for a threading table in a looper such as a continuous annealing furnace.

In FIG. 11, a plurality of sets of rolls 32 are provided.
However, since the steel plates S are arranged in an inverted C-shape inclined by θ1 °, the dynamic frictional forces F1, F2 received by the steel plate S from the rolls 32 are
Are decomposed into F1X, F1Y, and F2X, F2Y, respectively.

F1 = μ × m1 × g (1) F2 = μ × m2 × g (2) (μ: dynamic friction coefficient between the steel plate S and the roll 32, m
1, m2: distributed load (kg) of the steel plate S per roll 32, g: gravitational acceleration (9.8 m / s ² )) and F1X = F1 × sin θ1 (3) F1Y = F1 × cos θ1 (4) F2X = F2 × sin θ1 (5) F2Y = F2 × cos θ1 (6)

For example, when the steel plate S is going to meander to the right as viewed from the conveying direction D with the meandering force Fk, the roll 3
The distributed load ml applied to 2 becomes smaller and m2 becomes larger. Therefore, F1X becomes smaller, F2X becomes larger, and the difference between F1X and F2X is the centering force ΔF (=
F2X-F1X) will act on the steel sheet. If the centering force ΔF is larger than the meandering force Fk of the steel sheet, the steel sheet is centered so that it follows the path.
It is corrected to the point where F and the meandering force Fk of the steel plate are balanced with each other, but the plate is passed with a large or small offset.

[0007]

However, the meandering preventive device 31 having the rolls 32 arranged in an inverted C shape as shown in FIG. 11 can center the steel plate S by the force of only its own weight. Therefore, in order to exert the centering function by F1X or F2X generated by the roll 32, it is necessary to use several tens to several hundreds of rolls. In addition, if there are many rolls, the rolls will be worn and the maintenance work such as replacing the rolls and the cost will be very difficult.

In particular, when the steel sheet to be conveyed has an ear wave or a medium wave and the shape is very bad, or when the tension is uneven in the width direction due to a single wave, the meandering of the steel sheet. The force Fk may greatly exceed the centering force ΔF, and the steel sheet may reach the roll-out and cause the sheet to break.

[0009] Here, the ear wave means that both edges of the steel plate have a wavy shape, the middle wave means that the central portion of the steel plate has a wave shape, and the half wave means that of the steel plate. One edge has a wavy shape. When there is an ear wave and a medium wave, the contact with the inverted C-shaped roll is likely to be non-uniform, and the steel sheet tends to shift to the left or right. Also,
If there is a unilateral wave, the tension will be uneven in the width direction and will be greatly offset in the wavy shape.

Moreover, the rolls arranged in the inverted C-shape are used only in the horizontal pass such as the threading table in the looper such as the continuous annealing furnace, and the tension like the free loop is almost generated. If the passing table length is short, or in the case of a vertical path (a path in which the steel sheet extends in the vertical direction), the rolls 32 arranged in the inverted C shape cannot be used. Therefore, conventionally, the side guide roll type meandering preventing device shown in FIG. 12 is often used in the vertical path.

The side guide roll type meandering prevention device 34 shown in FIG.
The roll 35 is preset by the motor 36 according to the plate width of the steel plate S.

However, the meandering prevention device 3 shown in FIG.
In the case of 4, since the roll 35 directly contacts the steel plate S, there is a problem that the edge of the steel plate S is damaged if the pressing force is too strong or there is a preset mistake.

The present invention has been made to solve the above problems, and it is possible to improve the centering force of a steel sheet with a small number of rolls, to use it in a vertical pass, and to prevent the meandering prevention device from damaging the steel sheet. Another object of the present invention is to provide a method for preventing meandering of a steel sheet using the same.

[0014]

According to a meandering prevention device for a steel plate of the present invention, a plurality of sets of rolls supporting strip-shaped steel plates continuously threaded along a predetermined path have a center of the predetermined path. A meandering prevention device for steel plates that is arranged so as to incline in an inverted C shape so as to be directed to the downstream side in the transport direction of the steel plate as it is separated from the line in the width direction of the steel plate, and is adjacent in line in the transport direction of the steel plate. A magnet is arranged between the two rolls so as not to contact the steel plate.

It is preferable that the magnet is inclined so as to come closer to the steel plate as the magnet moves away from the center line of the predetermined path in the width direction of the steel plate.

It is preferable that the roll can swing about a fulcrum arranged near the center line of the predetermined path.

It is preferable that the magnet can swing about a fulcrum arranged near the center line of the predetermined path.

It is preferable to have a stopper for regulating the angle at which the roll or magnet swings.

It is preferable to have elastic means for giving a restoring force when the roll or magnet swings.

Further, in the method for preventing the meandering of a steel sheet using the meandering preventing device for a steel strip according to the present invention, the meandering preventing device is installed in a vertical path in which the steel sheet is bent in a loop shape and tension is not substantially applied. It is characterized by preventing the meandering.

In the steel plate meandering preventive device of the present invention, a plurality of sets of rolls supporting strip-shaped steel plates continuously threaded along a predetermined path are arranged in the width direction of the steel plate from the center line of the predetermined path. Has a roll arranged so as to incline in an inverted C shape so as to be directed to the downstream side in the transport direction of the steel sheet, a so-called inverted C-shaped roll, and further adjacent in line in the transport direction of the steel sheet. A magnet is arranged between the two rolls so as not to contact the steel plate. Therefore, a sufficient centering force of the steel plate can be obtained by the resultant force of the weight of the steel plate and the attractive force of the magnet.

If the magnet is inclined so as to come closer to the steel plate as it goes away from the center line of the predetermined path in the width direction of the steel plate, the steel plate and the magnet are separated as the steel plate meanders and deviates from the predetermined path. As the distance becomes shorter, the attraction force of the magnet to the steel sheet increases as the distance becomes shorter, and the centering force of the steel sheet can be further strengthened.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Next, with reference to the drawings, a steel plate meandering preventive device and a steel plate meandering preventing method using the same will be described in detail. FIG. 1 is an explanatory view of a path of a steel plate showing a place where the steel plate meandering prevention device of the present invention is installed, FIG. 2 is a plan view showing an embodiment of the steel plate meandering prevention device of the present invention, and FIG. III-III line sectional view of FIG. 4, FIG. 4 is a partial enlarged view of a meandering preventive device having horizontally arranged magnets showing another embodiment of the meandering preventive device of the steel sheet of the present invention, and FIG. FIG. 6 is a partially enlarged view of a roll seesaw type meandering preventive device showing still another example of the meandering preventive device, and FIG. 6 shows a magnetic seesaw type meandering preventive device part showing still another example of the steel plate meandering preventive device of the present invention. FIG.

As shown in FIG. 1, the meandering prevention device 1 for a steel plate S of the present embodiment presses the steel plate S against a roll by utilizing not only the weight of the steel plate S but also the attractive force of a magnet as described later. Let Therefore, not only the vertical pass looper VLP of a continuous annealing furnace but also the free loop FL or the vertical pass VP between the bridle roll BR and the free loop FL before the vertical pass looper VLP is installed to prevent the meandering of the steel sheet S. You can In this case, the edge of the steel sheet S is hardly damaged as compared with the case where the conventional side guide roll 35 (see FIG. 12) is used. Needless to say, the roller 32 may be installed on the horizontal path HP like the conventional inverted C-shaped roll 32 (see FIG. 11). In FIG. 1, WD is a welder,
TR is a trimmer.

Although not shown, the meandering prevention device 1 may be installed on the horizontal pass looper. The horizontal pass looper has a shape in which the vertical pass looper VLP shown in FIG. 1 is just laid down horizontally, and a cart called a loop car is installed in a portion corresponding to a weight (WE). The horizontal path length is about 100 m, and the structure is such that the amount of steel plate accumulated can be adjusted by moving the carriage.

As shown in FIGS. 2 and 3, the meandering prevention device 1 for the steel plate S comprises a roll 2, a magnet 3, and a stage 4 supporting the roll 2 and the magnet 3.

The rolls 2 are composed of a plurality of sets of rolls for supporting strip-shaped steel plates S which are continuously passed through a predetermined path, and are rotatably supported on the stage 4. The rolls 2 of each set are arranged in an inverted V shape so as to be directed toward the downstream side in the conveying direction of the steel sheet S as they are separated from the center line C of the predetermined path in the width direction of the steel sheet S by 2 ° (about 4 to 5 °). )
It is placed at an angle. The center line C of the predetermined path passes through the intermediate position of the rolls 2 of each set. When the angle is increased, the controlled state becomes vibrated when the angle is increased, and the roll is often worn. On the other hand, when the angle is small, the controllability is deteriorated. Therefore, θ2 ° is preferably set to 4 to 5 °.

The roll 2 may be made of various materials or shapes as long as it can support the steel plate S, but it is most preferable that the roll 2 is softer than the steel plate and has a large friction coefficient. For example, if a roll in which a spiral groove is formed on the surface of the roll 2 in order to increase the friction coefficient, that is, a so-called threading roll is used, the centering force of the steel plate S can be further increased. Also, roll 2
Is preferably made of a urethane resin because it is less likely to rub than a conventional MC nylon-based roll and does not damage the steel plate S. Alternatively, the angle θ2 ° at which the roll 2 is inclined in the inverted V shape may be adjustable.

The magnet 3 is arranged on the stage 4 so as to be separated from the steel plate S so as not to come into contact with the steel plate S between two adjacent rolls 2 lined up in the conveying direction of the steel plate S.

The distance between the magnet 3 and the steel plate S is adjusted by the following procedure.

First, the roll distance is set. Steel plate S
The distance between two adjacent rolls in the transport direction of
It is important to have the smallest dimensions. Furthermore, it is necessary to consider the size of the magnet. Therefore, the distance between the rolls is set to about 200 mm.

Next, the thinnest steel plate among the steel plates to be passed over the roll 2 is placed. After that, steel plate S
The magnet 3 is approached from below, and the distance for fixing the magnet 3 immediately before the steel plate S is attracted is set to about 15 to 20 mm.

As shown in FIG. 7, the inclination of the magnet 3 is set so that the outer side is about 15 to 20 mm and the inner side is twice that (30 to 40 mm).

If the magnet 3 is tilted in this way, the state shown in FIG.
As is clear from the graph of (b), since the attractive force of the magnet is inversely proportional to the square of the distance,
When the outer suction force is 100, the inner suction force is about 25.

In FIG. 2, since a plurality of sets of rolls 2 are arranged in an inverted C-shape inclined by θ2 °, the dynamic frictional forces F3 and F4 received by the steel plate S from the rolls 2 are F3X and F3Y, respectively. , And F4X and F4Y.

Here, F3 = μ × m3 × g + FM1 × μ × α (7) F4 = μ × m4 × g + FM2 × μ × α (8) (μ: dynamic friction coefficient between the steel plate S and the roll 2, m
3, m4: distributed load (kg) of the steel plate S per one roll 2, g: gravitational acceleration (9.8 m / s ² ), FM
1, FM2: attraction force (kgf) for the steel plate S on a predetermined path per one magnet 3, α: area correction coefficient)

Here, the area correction coefficient α will be described. Without the magnet, the tensioned steel plate S makes almost line contact with the roll 2. On the other hand, when the magnet 3 is provided as in the present invention, as shown in FIG. 8, the steel plate S is attracted by the magnetic force FM1 even when tension is applied, so that the steel plate S winds around the roll 2, It becomes surface contact. According to the experimental result, the tension is 1 kg / mm ² , m × g≈
The area correction coefficient α is 20 to 30 under the condition of FM1, and a centering force equivalent to 20 to 30 inverted C-shaped rolls can be obtained. If the tension is large, the winding area S
m (area of triangular region indicated by broken line in FIG. 8A)
However, if the tension is small, the winding area Sm can be increased, but the magnetic forces FM1 and FM2 cannot be increased from the viewpoint of adsorption of the steel sheet. is there. Therefore, the area correction coefficient α is not a fixed value because it changes according to changes in the tension or the magnetic force.

[0038]

[Equation 1]

(B: magnetic flux density (T), So: magnet area (m ² ), uo: magnetic permeability in vacuum (= 4π × 10 ⁻⁷ )) and F3X = F3 × sin θ2 (10) F3Y = F3 × cos θ2 (11) F4X = F4 × sin θ2 (12) F4Y = F4 × cos θ2 (13)

When the steel plate S deviates from a predetermined path and tries to meander, either of the distributed loads m3 and m4 and the magnet attraction forces FM1 and FM2 applied to either the right or left roll 32 becomes large. Therefore, the difference between F3X and F4X acts on the steel sheet S as the centering force ΔF (= F4X-F3X), and the steel sheet S is corrected along the predetermined path. At this time, the steel plate S is more strongly pressed against the roll 2 than the conventional one by the resultant force of the self-weight of the steel plate S and the attractive force of the magnet 3, so that the two or three rolls 2
It is possible to obtain the centering force of the steel plate S equivalent to several tens of steel sheets.

The magnet 3 shown in FIGS. 2 to 3 has a frame 3 having a U-shaped cross section in which the surface facing the magnet block 3a and the steel plate S for housing the magnet block 3a is open.
b and. The magnet block 3a can move inside the frame 3b, and can be positioned at any position by a positioning knob (not shown).

Further, as shown in FIG.
Is inclined so as to approach the steel plate S as it moves away from the center line C of the predetermined path in the width direction of the steel plate S.

The distance between the steel plate S and the magnet 3 is determined according to the above procedure.
And is set based on FIG. When the magnets 3 are arranged so as to be inclined, a large centering force ΔF can be obtained as compared with the case where the magnets 3 are arranged horizontally. This point will be described in detail below with reference to FIGS. 9 to 10 (note that FIG. 10 is common to the arrangement of the magnets 3 of the meandering preventive device shown in FIG. 4 described later).

When the magnets 3 are arranged at an angle (see FIG. 9).
2) of the horizontal arrangement (see FIG. 10) and the horizontal arrangement (see FIG. 10). component force F3X, F4X centering force ΔF to each move to P _1, P ₂ from the position of the symmetric (= F4X-F3X) occurs. When comparing the centering forces ΔF in FIGS. 9 to 10, the centering force ΔF in FIG. 9 in which the magnet 3 is tilted is much larger. This is because the magnetic force is inversely proportional to the square of the distance as described above. On the other hand, as shown in FIG. 10, when the magnets 3 are horizontally arranged, when the pair of left and right magnets 3 is viewed, the attraction force of the right magnet 3 is relatively stronger, but the position of the steel plate S The relationship between F3X and F3X or F4X is only proportional, and as a result, FIG.
The centering force ΔF shown in FIG. 10 is smaller than the centering force ΔF shown in FIG.

As another embodiment, even when the magnet 3 shown in FIG. 4 is arranged so as to be parallel to the steel plate S, the force due to the self-weight of the steel plate S and the attraction force of the magnet 3 are generated. Due to the resultant force, a stronger centering force of the steel plate S than before can be obtained.

As yet another embodiment, as shown in FIG. 5, it is preferable that the roll 2 can swing about a fulcrum arranged near the center line C of a predetermined path.

In the example shown in FIG. 5, the swing table 6 is swingably supported by the pin 5 which is a fulcrum with respect to the stage 4, and the roll 2 is rotatably supported by the swing table 6. . With this configuration, when the steel plate S starts to meander, the attracting force of the magnet 3 on one side of the steel plate S becomes larger than that on the opposite side, so that the steel plate S and the roll 2 swing around the pin 5, The distance between the steel plate S and the magnet 3 can be shortened. Thereby, the magnet 3
The suction power of can be increased. As a result, the magnet 3
3 to 4, the centering force of the steel plate S can be further strengthened and the controllability of the steel plate S (in other words, the responsiveness of the correction operation) can be increased. Will get better.

As another embodiment, as shown in FIG. 6, it is preferable that the magnet 3 can swing around a fulcrum arranged near the center line C of a predetermined path.
The example shown in FIG. 6 is different from the case of FIG. 5 in that a magnet 3 is provided in place of the roll 2 on the swing table 6, and in other respects, the configuration is common to FIG. There is. In the case of FIG. 6, when the steel plate S starts to meander, the attracting force of the magnet 3 on one side of the steel plate S becomes larger than that on the opposite side, so that the magnet 3 swings around the pin 5, so that the steel plate The distance between S and the magnet 3 can be shortened.
Thereby, the attractive force of the magnet 3 can be increased. Further, as in the case described above, the attraction force of the magnet 3 can be further increased as compared with the case of FIGS.
The centering force of the steel plate S can be further strengthened,
The controllability of the steel plate S is improved.

As still another embodiment, the example of FIG. 5 and FIG.
As an example in which the rolls 2 and the magnets 3 are both provided on a dedicated rocking table 6 so as to be rockable, as compared with the case of FIGS. The distance from the magnet 3 can be shortened. Thereby, the attractive force of the magnet can be further increased, and as a result, the centering force of the steel plate S can be further strengthened and the controllability of the steel plate S can be further improved.

As shown in FIGS. 5 and 6, the roll 2
And / or it is preferable to have a stopper 7 in order to regulate the angle at which the magnet 3 swings. The stopper 7 can regulate the angle at which the roll 2 or the magnet 3 swings by colliding with the swing table 6. If a bolt or the like is used as the stopper 7, an arbitrary swing angle can be set by adjusting the height of the tip of the bolt.

Further, as shown in FIGS. 5 and 6, it is preferable to have elastic means for giving a restoring force when the roll 2 or the magnet 3 swings. 5 to 6, the tension coil spring 8 is used as the elastic means, but various known elastic means such as rubber may be used instead. By using the elastic means, it is possible to quickly balance the left and right even if the roll 2 and / or the magnet 3 sways along with the meandering of the steel plate S, which is preferable in that the posture can be stabilized.

[0052]

According to the present invention, the centering force of a steel sheet can be improved with a small number of rolls. Moreover, since the steel plate is pressed against the roll by using the attractive force of the magnet, it can be used even in the vertical pass, and the steel plate is not damaged unlike the conventional case.

Therefore, in a place such as a free loop where the restraining force of the steel sheet is very weak, the centering force can be applied to the steel sheet by attracting the steel sheet to the inverted C-shaped roll by the attractive force of the magnet. Therefore, it is possible to stably pass the steel plate, and it is possible to further speed up the line.

Further, conventionally, by using a magnet roll or the like having a magnet built in the roll, iron powder adhered to the roll surface, causing a problem such as scratches on the steel plate surface. In the present invention, since the roll and the magnet are separated and the magnet and the steel plate are not in contact with each other, there is no fear of damaging the steel plate.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a path of a steel plate showing a place where a meandering prevention device for a steel plate of the present invention is installed.

FIG. 2 is a plan view showing one embodiment of the steel plate meandering preventive device of the present invention.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a partially enlarged view of a meandering prevention device having horizontally arranged magnets showing another embodiment of the steel plate meandering prevention device of the present invention.

FIG. 5 is a partially enlarged view of a roll seesaw type meandering preventive device showing still another embodiment of the meandering preventive device for a steel plate of the present invention.

FIG. 6 is a partially enlarged view of a magnet seesaw type meandering preventive device showing still another embodiment of the meandering preventive device for a steel plate of the present invention.

7 is an explanatory diagram showing a relationship between a magnet force and a distance between a steel plate and a magnet of the meandering preventive device of FIG.

FIG. 8 is an explanatory diagram showing a state in which a steel plate is wrapped around the roll of FIG.

9 is an explanatory diagram showing the magnitude of a centering force ΔF generated when the steel sheet is deviated in the meandering prevention device of FIG. 2.

10 is an explanatory diagram showing the magnitude of a centering force ΔF generated when the steel sheet is deviated in the meandering prevention device of FIG.

FIG. 11 is a plan view of a conventional inverted V-shaped roll type steel plate meandering prevention device.

FIG. 12 is a front view of a conventional side guide roll type steel plate meandering prevention device.

[Explanation of symbols]

1 Meandering prevention device Two rolls 3 magnets 4 stages

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B21B 39/14 B21C 47/34 C21D 9/56 101

Claims (7)

(57) [Claims] 1. A conveying direction of the steel sheet as a plurality of sets of rolls supporting strip-shaped steel sheets continuously threaded along a predetermined path are separated from a center line of the predetermined path in a width direction of the steel sheet. Is a meandering prevention device for a steel plate that is arranged so as to face the downstream side in a reverse V shape so as not to come into contact with the steel plate between two adjacent rolls lined up in the transport direction of the steel plate. A meandering prevention device for a steel plate, which is provided with a magnet. 2. The apparatus for preventing meandering of a steel strip according to claim 1, wherein the magnet is inclined so as to come closer to the steel sheet as the magnet moves away from the center line of the predetermined path in the width direction of the steel sheet. 3. The steel strip meandering prevention device according to claim 1, wherein the roll can swing about a fulcrum arranged near a center line of the predetermined path. 4. The magnet according to claim 1, wherein the magnet can swing about a fulcrum arranged near a center line of the predetermined path.
Or the steel strip meandering prevention device described in 3. 5. The meandering prevention device for a steel strip according to claim 3, further comprising a stopper for regulating an angle at which the roll or the magnet swings. 6. An elastic means for applying a restoring force when the roll or the magnet swings.
The steel strip meandering prevention device described. 7. A method of preventing meandering of a steel sheet using the meandering preventive device for a steel strip according to claim 1, 2, 3, 4, 5 or 6, wherein the steel sheet is bent in a loop shape and has a substantial tension. A method for preventing the meandering of a steel sheet, wherein the meandering preventive device is installed in a vertical path that does not affect the meandering of the steel sheet.