JPH0790389A - Method for straightening shape of metal sheet and device therefor - Google Patents

Abstract

PURPOSE:To provide a shape straightening method and a device therefor, in which waving in bad shape defect part is changed as a float-up state from roll outer peripheral surface by winding silicon steel sheet passing through a heating zone of a horizontal type continuous annealing furnace by low tension around a roll to flatten the shape after soaking by giving to the shape defect part the same elongation ratio due to a difference in temp. as that by the float-up and by applying a skin kable and compressive stress to the shape defect part while restricting the outer surface deformation of the steel sheet. CONSTITUTION:Three self-traveling rotation-drive winding rolls 3a-3c each composed of suction rolls having radius of <=1500 times the steel sheet thickness are arranged in the state of difference in grade in the heating zone 1 of the horizontal type continuous annealing furnace. A heating heater board 4 being shiftable in the width direction of the steel sheet S so as to match the position of the shape defect part developed in the silicon steel sheet S, is fitted to a hydraulic cylinder 5. A steel belt 6b of the self-traveling type belt mechanism 6 is pushed to the silicon steel sheet S wound around the winding roll 3b at the center part so as to become >=3cm of pushing length.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shape straightening method and apparatus in a continuous annealing furnace for continuously performing heat treatment such as heating, soaking and cooling while passing a metal strip such as a strip horizontally or substantially horizontally. In particular, it is suitable for a metal strip in which the tension applied to the metal strip in the threaded plate must be controlled to be small.

[0002]

2. Description of the Related Art Generally, in a continuous annealing furnace in which a steel sheet is made into a series of metal strips, that is, strips, and the strips are annealed continuously, temperature nonuniformity in the width direction of the strips during cooling causes defective shape of the strips. Is well known. On the other hand, it is well known that the shape defect of the strip can be largely corrected by appropriately controlling the temperature in the width direction of the strip during cooling. In a so-called vertical continuous annealing furnace, in which a proper tension is applied to the strip in the annealing furnace, and the strip is vertically folded, the strip is repeatedly wound around a hearth roll. Causes creep deformation in the longitudinal direction, which causes the strip to have a uniform temperature and a flat shape on the soaking side of the continuous annealing furnace. Therefore, the strip flatness after that, that is, shape control However, there is a history that cooling control must be very important. Various methods have been developed for this cooling control (for example, Japanese Patent Laid-Open No. 57-1016).
No. 22, JP-A-59-129727, JP-A-3-90520, etc.). The strip side flatness control by these cooling controls corrects the shape defect on the inlet side by applying sufficient tension in the soaking zone, and the strip becomes almost flat on the soaking side. However, this is because the effect of the above-mentioned creep on the product quality is negligible with ordinary cold-rolled steel sheets, and if the sheet thickness does not change, it is exceptional to apply the tension required for the shape correction. This was because there was no problem.

Incidentally, for example, according to Japanese Patent Laid-Open No. 56-227 proposed by the present applicant, when a steel sheet containing a silicon component such as a grain-oriented electrical steel sheet is continuously annealed as a series of strips, , For the secondary recrystallization required for the grain-oriented electrical steel sheet (hereinafter also referred to as a silicon steel sheet), which selectively grows grains having a normal Goss orientation, and for reducing impurities in the steel, 1000 in coil state
Finish annealing is performed at high temperature for a long time at temperatures above ℃.

The strip subjected to the high-temperature finish annealing in the coil shape as described above causes a very large shape defect due to the nonuniform temperature due to the coil winding tendency and the temperature rise of the lump. As a method for correcting the shape of an electromagnetic steel sheet having such a shape defect, generally, continuous annealing with a slight tension applied by a horizontal furnace is performed. Regarding the continuous annealing of such a grain-oriented electrical steel sheet, that is, a unidirectional silicon steel sheet or a non-oriented silicon steel sheet, the content of interest is disclosed in Japanese Patent Application Laid-Open No. 50-262920 previously proposed by the present applicant. ing. That is, in order to manufacture this type of silicon steel sheet as a product having stable magnetic characteristics, it is necessary to suppress the deterioration of the iron loss characteristics, which particularly appears in the magnetic characteristics. However, conventionally, in order to remove the winding curl generated in the previous step, continuous annealing is performed by applying a certain tension to these silicon steel sheets.
The addition of this tension inevitably causes the steel sheet to stretch,
It has been clarified that this elongation deteriorates the iron loss characteristics. Therefore, when such a silicon steel sheet is continuously annealed as a series of strips, a so-called horizontal continuous annealing furnace is adopted in which the strips are passed horizontally or almost horizontally in order to prevent the steel sheet from being tensioned. It was decided to be done. The invention described in Japanese Patent Laid-Open No. 60-262920 relates to continuous annealing developed to stabilize the magnetic properties of such a silicon steel sheet and to remove the curl in the preceding step. Is.

Now, returning to the actual state of the continuous annealing of the silicon steel sheet as described above, since the secondary recrystallization annealing temperature in the preceding step is extremely high, shape defects are likely to occur and the If high tension cannot be applied in the continuous annealing in the process due to the problem of magnetic properties, the strip shape defect that had become apparent on the inlet side of the continuous annealing furnace was hardly corrected in the furnace and was directly output on the outlet side. Will be reached. Therefore, the defective shape portion that cannot be subjected to high tension for shape correction is discarded without satisfying the quality of the product, and the yield is unavoidably reduced.

In continuous annealing in which high tension cannot be applied as described above, there is one disclosed in JP-A-61-204339 as one means for correcting a defective shape. In the continuous heat treatment method described in this publication, the outer cylinder portion constituting the rotatably driven winding roll is heated to a high temperature by heating means provided inside the outer cylinder portion, specifically, a heating medium flowing into the outer cylinder. By heating, the strip is closely transferred to the outer peripheral surface of the outer cylinder portion to increase the temperature of heat transfer, and the deformation of the strip due to the thread tension and thermal expansion is corrected on the outer peripheral surface of the winding roll. If this winding roll is used, the strip that is closely transferred to the rotatively driven winding roll is heated closely from the outer peripheral surface of the winding roll, so that high tension is applied to the strip in the threaded plate. Even if it does not, the amount of deformation of the strip due to thermal expansion can be suppressed.
Specifically, even if a large shape defect having a steepness of up to several percent, which will be described later, is wound in close contact with a winding roll at a high temperature, the large shape defect is slightly lifted from the winding roll. It can be changed into a defective shape,
Further, fluctuations in the strip, flapping, and the like can be suppressed by suppressing the temperature nonuniformity in the width direction of the strip due to the close contact temperature rise.

[0007]

However, in the winding roll described in Japanese Patent Laid-Open No. 61-204339, the defective shape of the strip is merely made inconspicuous by the winding of the roll, and the strip is actually wound. It is not a correction for the difference in elongation. In other words, roll winding suppresses strip fluctuations and flapping, and secures stable operation, but the strip's self-defective shape remains as it is. I will end up. This is because compressive stress does not act on the defective portion only by winding the roll.

The present invention has been developed in view of these various problems, and by winding it around a winding roll, a local large shape defect is changed into a gentle shape defect of floating from the roll, In order to apply a compressive stress to the shape defect part, by pressing the floating part from the roll against the winding roll, the shape defect of the metal strip is surely corrected, and / or the correction is made more effective. It is an object of the present invention to provide a method and apparatus for correcting the shape of a metal band, which can heat and heat the shape defect portion to increase the apparent shape defect before the correction.

[0009]

Means for Solving the Problems The inventors of the present invention have made extensive studies to solve the above-mentioned problems, and as a result, have obtained the following findings and developed the present invention. That is, it is considered that the shape defect that occurs in the strip is manifested in the form of local stretching in that portion as compared with the surrounding area, which is caused by the corrugation in the out-of-plane direction of the strip. There is. The following two methods can be easily considered as a method of correcting this.

(1) The circumference is extended to be equal to or more than the defective portion. (2) The shape-defective portion is shrunk to the same length as the surrounding area. Generally, the above-mentioned straightening by the tension in the furnace and other plastic working methods such as levelers and skin passes are also straightening using the principle according to (1). This is because the method of shrinking the defective shape portion as in (2), that is, it cannot be achieved unless the out-of-plane deformation of the defective shape portion is restricted.

Here, as a method for restraining the out-of-plane deformation of the strip, for example, a flat plate clamp as shown in FIG. 8 or a caterpillar clamp as shown in FIG. 9 can be easily considered. However, in consideration of application to strips that are continuously threaded or use in a high-temperature furnace, for example, the former may cause flaws on the strip surface, and the latter may cause malfunction at high temperatures. There is a little lack of reality.

By the way, when the strip is wound around a winding roll at a high temperature as described in JP-A-61-204339, the shape defect manifested as deformation in the out-of-plane direction in the shape defect portion. Changes into the form of floating from the winding roll. If the lift of the strip from the winding roll is pressed by a means that does not apply tension to the strip, it is possible to apply a compressive stress that reduces the lift while restraining the out-of-plane deformation.

Further, even if the straightening is performed by pressing the roll in this way, some floating is always left within the range of elastic recovery. Therefore, it was noted that if a temperature deviation corresponding to this elongation is given to the shape defect portion, the strip has a uniform temperature and a flat shape at least in the state where the temperature deviation disappears on the soaking zone side. Thus, the method for straightening the shape of a metal strip according to claim 1 of the present invention is a method for straightening the shape of a metal strip that is passed through a plate in a horizontal continuous annealing furnace. The metal strip wound around the outer peripheral surface of the winding roll provided inside is pressed against the outer peripheral surface of the winding roll.

The method of straightening the shape of a metal strip according to claim 2 of the present invention is a method of straightening the shape of a metal strip to be threaded in a horizontal continuous annealing furnace. Before the metal band is wound on the outer peripheral surface of the winding roll provided inside or at the time of winding, the heating means provided outside the winding roll performs local heating in the width direction of the metal band. It is what

The method of straightening the shape of a metal strip according to claim 3 of the present invention is a method of straightening the shape of a metal strip that is passed through a plate in a horizontal continuous annealing furnace. Before or at the time of winding the metal strip on the outer peripheral surface of the winding roll provided inside, the heating means provided outside the winding roll performs local heating in the width direction of the metal strip, and It is characterized in that the metal strip is pressed against the outer peripheral surface of the winding roll.

A metal strip shape straightening device according to a fourth aspect of the present invention is a device for straightening the shape of a metal strip to be passed through a horizontal continuous annealing furnace. Before or at the time of winding the metal strip around the outer surface of the winding roll provided inside, one or more local heating mechanisms for performing local heating in the width direction of the metal strip are provided outside the winding roll. It is a feature.

The apparatus for straightening the shape of a metal strip according to claim 5 of the present invention is an apparatus for straightening the shape of a metal strip that is threaded in a horizontal continuous annealing furnace. The metal strip wound on the winding roll provided inside
The present invention is characterized in that at least one pressing mechanism for pressing the winding roll is provided. The shape correcting device for a metal strip according to claim 6 of the present invention is a horizontal continuous annealing furnace,
An apparatus for correcting the shape of a metal strip to be threaded, characterized in that the local heating mechanism and the pressing mechanism are arranged in parallel.

In the shape correcting device for a metal strip according to a seventh aspect of the present invention, the local heating mechanism is a heater heater board provided outside the winding roll and movable in the width direction of the metal strip. It is characterized by being configured. The shape correcting device for a metal band according to claim 8 of the present invention is characterized in that the winding roll is set to a radius of 1500 times or less the plate thickness of the metal band.

In the shape correcting device for a metal band according to claim 9 of the present invention, the pressing mechanism has one pressing mechanism, and the pressing length of the metal band to the winding roll is set to 3 cm or more. It is what The shape correcting device for a metal band according to claim 10 of the present invention is characterized in that the pressing mechanism is configured by a belt mechanism capable of traveling in the plate passing direction along with the plate passing of the metal band. is there.

The shape correcting device for a metal band according to claim 11 of the present invention is characterized in that the winding roll is a suction roll. According to a twelfth aspect of the present invention, in the apparatus for correcting a shape of a metal strip, the winding roll is installed in a heating zone in a horizontal continuous annealing furnace.

[0021]

As described above, when a metal band heated to a high temperature, that is, a strip, is wound around a winding roll, the shape defect that is manifested as waviness at the shape defect portion is called floating from the outer peripheral surface of the roll. Change in shape. Looking at the relationship between the floating amount h and the winding angle θ, as shown in FIG. 3, a predetermined winding angle θ (a winding angle of 10 ° or more in the figure).
If it is wrapped with, it will converge to a substantially constant value δ. That is, in the case where there is no device means such as a pressing mechanism for applying a compressive stress from the outside in this way, no matter how much the winding angle θ is increased, as shown in FIG. There is a quantity δ.

Here, as shown in FIG. 4, when the steepness λ of the defective shape of the strip wound on the winding roll having the radius R is represented by the out-of-plane deformation amount H and the contact width L, the present application As described in Japanese Patent Laid-Open No. 1-168821 previously proposed by a person, λ = H / L, and the elongation rate ε _{0 in} this case is given by the following equation 1. _{ε 0 = ((π / 2} ) · λ) 2 ≒ 2.47λ 2 ......... (1) Further, uplift amount h generated in the shape defect portion in a state wound around the strip winding roll, The elongation rate ε when the radius of the winding roll is R is given by the following two equations.

Ε = h / R (2) Since the elongation rate ε itself is the same as the elongation rate ε ₀ of the shape-defective portion given by the above equation 1, the following equation is obtained from both and the correlation is calculated. FIG. 4 shows it. h = 2.47 · R · λ ² (3) When the winding angle is shallow in FIG. 3, the strip does not completely match the roll curvature, and as a result, R (strip)> R ( Roll), and the lift amount h increases. When the winding angle exceeds a certain value, R (strip) ≈R (roll), and at this time, the residual lift amount δ is considered to be equal to the roll curvature, particularly the lift amount corresponding to the strip shape defect.

Therefore, in the metal strip shape correcting method according to claim 2 or the metal strip shape correcting apparatus according to claim 5 of the present invention, the steepness of the defective portion is λ on the winding roll having the radius R. The lifting amount h given by the above-mentioned formula 3 generated when a certain strip is wound under high temperature is pressed against the outer peripheral surface of the winding roll by a pressing mechanism or the like, thereby restraining the out-of-plane deformation of the strip. By applying a compressive stress to the difference in elongation existing as the floating amount h, the defective shape portion can be shrunk to the same extent as other surrounding portions to correct the shape.

In the shape correcting method for a metal band according to claim 3 or the shape correcting device for a metal band according to claim 6 of the present invention, the apparent shape at the time of winding by such local heating. By increasing, the action and effect of pressing the winding roll in the winding direction can be further improved. Further, even after the shape is corrected by the winding roll, the shape defect remains due to the elastic recovery, but by providing a temperature difference corresponding to this, a perfect flat shape can be obtained when the temperature is uniform.

On the other hand, the residual floating amount δ that remains steadily when the winding angle in FIG. 3 is increased is sorted by the diameter of the winding roll and the size of the defective shape.
That is, it is expressed as shown in the above equation 2, and the larger the roll diameter or the larger the defective shape, the larger the lift amount δ. By the way, when the lift amount δ becomes large as compared with the plate thickness t, buckling occurs at the time of pressing against the winding roll, and there is a risk that the strip is squeezed. From this viewpoint, it is necessary to set the lift amount-plate thickness ratio δ / t to about 3 or less. Therefore, when the above equation 3 is modified and a steepness of up to about 3% is taken into consideration, the floating amount-plate thickness ratio δ / t becomes 1350 or less. By setting a margin for a slight shape defect and setting the floating amount-plate thickness ratio δ / t to 1500 or less, wrinkles and drawing of the strip do not occur for a large shape defect, and stable shape correction is possible. It will be possible.

By the way, the above-mentioned compressive stress can be regarded as a surface pressure per a predetermined area, but the lift amount h manifested by the winding around the winding roll is further concerned by the pressing mechanism or the like. In order to press the outer peripheral surface of the winding roll and to apply the compressive stress to the defective shape while restraining the out-of-plane deformation of the strip, it is necessary to uniformly press the entire width direction of the strip. At this time, as shown in FIG. 6, the pressing mechanism is a small-diameter roll that is longer than the entire width of the strip, and a plurality of small-diameter rolls (3 in FIG.
Even if the strips are pressed against the strip so as to make line contact (or point contact), the strip floats between the small-diameter rolls for pressing, and as a result, the out-of-plane deformation is restrained and it is effective for the defective shape part. Cannot apply compressive stress to. That is, in order to effectively apply a compressive stress to the defective shape portion, it is pressed against the winding roll with a certain area, that is, a sufficient length so that the elongation does not escape in the longitudinal direction of the strip. Need to do.

FIG. 7 shows the pressing length W and the amount of change Δh in the floating amount before and after the pressing portion. As is clear from the figure, when the pressing length W is 3 cm or more, the change amount Δh of the lift amount is almost “0”. This means that if the pressing length W is 3 cm or more, that is, the pressing does not allow extension of the shape-defective portion in the longitudinal direction of the strip to escape, thereby correcting the shape of the metal strip according to claim 9 of the present invention. In the device, since the pressing length W by the pressing mechanism is set to 3 cm or more, compressive stress can be effectively generated in the defective shape portion while restraining the out-of-plane deformation of the strip, and the defective shape is effectively corrected. You will be able to do it.

By the way, in order to obtain the pressing length as described above, when the pressing small diameter pinch roll as shown in FIG. 7 is used, at least one of the rolls is made of a material having a large elastic deformation amount, for example, a high material. Although it must be made of flexible rubber or resin, it is unrealistic in view of the high-temperature furnace atmosphere, heating by the local heating mechanism, and the like. Therefore, in the shape correcting device for a metal strip according to claim 10 of the present invention, since the strip band is configured with a belt mechanism capable of running in the direction of the strip, for example, the belt mechanism may be a steel belt or the like. If it is made of a material that is excellent in heat resistance and has sufficient shape conformability to the strip wound on the outer peripheral surface of the winding roll, it can be used as a strip threading plate while obtaining the effective pressing length. Accordingly, the self-propelled structure prevents unnecessary tension or scratches on the surface of the strip.

Further, in the shape correcting device for a metal strip according to claim 11 of the present invention, the winding roll relating to each of the above-mentioned inventions is constituted by a suction roll, so that, for example, the strip floats due to the residual lift amount. To improve the adhesion to the outer peripheral surface, effectively obtain the pressing length by the pressing mechanism, etc., and efficiently apply compressive stress to the defective shape portion, and correct the shape of the defective shape portion. It is possible to do positively.

Now, in order to establish the above-mentioned shape correcting method, it is only necessary that the strip is in a high temperature region where creep deformation occurs based on desired steel plate specifications. However, in a series of continuous annealing furnaces substantially carried out, for example in soaking, soaking temperature is generally set in order to control the metallurgical properties of the strip, that is, the steel sheet,
Since this soaking temperature should be stabilized as much as possible over the entire steel plate in order to ensure the uniformity of the material quality, it would be problematic to carry out local heating as described above to add temperature deviation. Conceivable. Further, in the cooling zone of the series of continuous annealing furnaces, the occurrence of the shape defect due to the non-uniform cooling cannot be avoided as described above, and thus the local heating as described above is performed to correct the shape by adding the temperature deviation. Things would be difficult. In this respect, in the case of the heating zone of a series of continuous annealing furnaces, even if the temperature deviation due to the local heating is generated, as long as it is still in the middle of heating, it is necessary to make the temperature of the entire steel plate uniform in the soaking zone. Since the shape correction can be completed by the side of the soaking zone, the above-mentioned conventional technique can be effectively applied to the shape control in the cooling zone continuous to it. From the above, in the shape correcting method and apparatus for a metal strip according to claim 12 of the present invention, the above-described various shape corrections are performed in the heating zone of the horizontal continuous annealing furnace.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the method and apparatus for correcting the shape of a metal strip according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a first embodiment of a heating zone of a continuous annealing furnace using the metal strip shape correcting method and apparatus of the present invention. The present embodiment relates to a horizontal continuous annealing furnace for continuously annealing a strip formed by continuously connecting various steel plates including the above-mentioned silicon steel plate.

Reference numeral 1 shown in the figure is a heating zone of a continuous annealing furnace, and the strip S is continuously heated in the heating zone 1 by a radiant heating device such as a radiant tube (not shown) provided in the heating zone 1. While being heated and heated, the plate is passed horizontally or substantially horizontally in the direction of arrow a in the figure, and is fed horizontally or substantially horizontally even in the continuous soaking zone 2. The strip S, which is passed through the heating zone 1 horizontally or substantially horizontally, is supported by hearth rolls 10a and 10b provided on the inlet side and the outlet side of the heating zone 1, respectively. The rolls 10a and 10b are rotationally driven by an appropriate rotary drive mechanism (not shown) or driven and rotated by a frictional force between the strip S and the strip S as the strip S passes through, so that the magnetic properties of the silicon steel sheet are not affected. Thus, the tension applied to the strip S is reduced as much as possible.

The both hearth rolls 10a, 10
A plurality of winding rolls 3a to 3c are arranged between b. In this embodiment, these winding rolls 3a to 3c are used.
Are arranged in a so-called dancer roll shape, which is vertically displaced with respect to the strip passing direction of the strip S, and the strip S is wound around the winding rolls 3a to 3c at a winding angle of 10 ° or more. I was able to wrap it. Specifically, in this embodiment, the upper ends of the outer peripheral surfaces of the inlet and outlet winding rolls 3a and 3c are set to be equal to the height of the hearth rolls 10a and 10b, and the strips S from the winding rolls 3a and 3c are set. Each winding roll 3 at a place separated by about the plate thickness of
Since the central winding roll 3b is arranged at a position shifted downward by about a radius of a and 3c, the winding rolls 3a and 3c on the input side and the output side are arranged at about 1/4 of the outer peripheral surface thereof. The strip S is wound with a corresponding winding length, and the strip S is wound with a winding length corresponding to about 1/2 circumference of the outer peripheral surface of the central winding roll 3b. In addition,
These winding rolls 3 are rotationally driven by an appropriate rotary drive mechanism (not shown), or are driven to rotate by the frictional force between the strip S and the strip S in association with the passage of the strip S, thereby affecting the magnetic characteristics of the silicon steel sheet. The tension applied to the strip S is reduced as much as possible so as not to exert it.

The strips S wound around the winding rolls 3a to 3c are sucked into the winding rolls 3a to 3c by sucking the atmosphere gas from the small holes formed in the outer peripheral surfaces of the rolls. So-called suction rolls that adsorb are used. By winding the heated and heated strip S around these winding rolls 3a to 3c, the shape defect manifested by the steepness of the shape defect portion of each steel plate causes the outer peripheral surface of the roll as described above. Each of the winding rolls 3a to
The radius of 3c is 15 of the steel plate thickness of the strip S to be passed.
It is set to 00 times or less. As a result, if the strip S is wound around the winding roll 3 after the strip S is locally heated by the local heating mechanism described later or while the local heating is being performed, the steepness of the defective shape portion becomes apparent. The shape defect is manifested in the form of residual floating from the outer peripheral surface of the roll, and a temperature deviation corresponding to this residual floating is given to correct this defective shape until the 2nd side of the soaking zone. Is possible. In addition, in the strip S in which steel plates having different specifications are continuously wound, the winding of the strip S around the winding rolls 3a to 3c having a radius corresponding to 1500 times the plate thickness of each steel plate is performed while the strip S is continuously threaded. Since it is relatively difficult to change over the winding roll or replace the winding roll,
Usually, a roll radius corresponding to 1500 times the plate thickness is set according to the thinnest steel plate to be passed. By doing so, the radius of the winding rolls 3a to 3c is equal to or less than 1500 times the plate thickness of all the steel plates even for a steel plate having a plate thickness larger than this.

Then, these winding rolls 3a to 3c
Between the inlet side of the inlet, that is, the inlet side hearth roll 10a and the winding roll 3a.
At a position corresponding to before the strip S is wound around c, the heater heater boards 4 facing the both widthwise side surfaces of the strip S are arranged. These heater heater boards 4 appropriately heat and heat the so-called edge-stretching steel plate in which the strips S are stretched at both side edges in the width direction, and are continuously heated in the subsequent stage. Winding roll 3
This is for making the residual floating amount from the outer peripheral surface of the roll, which occurs when the strip S is wound around a to 3c, equal to the elongation rate due to the temperature deviation of the edge extending portion. Existing heaters conventionally used for heating zones, soaking zones, etc. can be diverted to these heater heater boards 4, but in the present embodiment, the heater heater boards 4 are moved in the width direction of the strip S. It is attached to a cylinder rod 5a of a hydraulic cylinder 5 which is a moving mechanism for. A position detection sensor (not shown) for detecting the position of the cylinder rod 5a or the heater heater board 4 is provided near the cylinder rod 5a, and the output from the position detection sensor collectively controls the operation of the continuous annealing furnace. It is output to the host computer.

The host computer tracks each steel plate having different specifications among the strips S to be threaded, and the heater heater board 4 is moved from both ends in the width direction of each steel plate according to the plate width of each steel plate. Control pressure is supplied to the hydraulic cylinder 5 in order to move it closer to or farther from the set position, and the output is stopped when the position detection value from the position detection sensor matches the set position. Control.

The host computer also uses the strip S based on data from a steel plate shape sensor (not shown).
The amount of heating and heating for detecting the shape of each of the steel plates that make up the steel plate and causing a temperature deviation according to the steepness of the edge extension of each steel plate,
That is, the temperature difference is calculated, and the electric power of the heating heater board 4 for achieving this temperature difference is supplied as a control signal to each heating heater board 4.

The edge extending portion thus provided with the predetermined temperature difference is lifted from the outer peripheral surface of the roll by being wound around the winding rolls 3a to 3c. The elongation rate corresponding to the amount is
Since it is controlled to be equal to the elongation rate due to the temperature difference based on the equation 5, it becomes flat after the soaking treatment for obtaining the predetermined metallurgical characteristics in the soaking zone 2 which is continuous in the latter stage. It has been corrected.

As a matter of course, the heating temperature rise in the heating zone 1 or by the heater board 4 depends on the winding rolls 3a to 3c.
It goes without saying that it is necessary to set the temperature at which the deformation due to creep progresses when the film is wound around. FIG. 2 shows a second embodiment of the heating zone of the continuous annealing furnace using the method and apparatus for correcting the shape of a metal strip of the present invention. This example relates to a horizontal continuous annealing furnace for continuously annealing strips formed by continuously forming various steel plates including the above-mentioned silicon steel plate, and the basic structure of the continuous annealing furnace is the same as that of the first embodiment. Also, the winding rolls 3a to 3c of the shape correction device
Since the configuration is substantially the same, these same components are given the same reference numerals as those in the first embodiment and the description thereof will be omitted.

In this embodiment, the location of the heater heater board 4 provided as the local heating mechanism is different from that of the first embodiment. In this embodiment, as shown in FIG. 2, two heater heater boards 4 are arranged on the upper surface of the strip S to be lined up in the width direction of the strip S. Each heating heater board 4 is formed in a substantially rectangular shape that is long in the longitudinal direction of the strip S and narrow in the width direction of the strip S, and its heating surface faces the upper surface of the strip S.

Each heater board 4 is attached to a cylinder rod 5a of a hydraulic cylinder 5 provided as a moving mechanism as in the first embodiment, and the cylinder rod 5a of the hydraulic cylinder 5 is expanded and contracted. By doing so, it is possible to move from the position shown by the solid line in FIG. 2a or FIG. 2c to the position shown by the phantom line. Therefore, when the heating / heating control similar to that in the first embodiment is performed by the host computer, the defective shape of each steel sheet is a so-called belly extension, which is caused by the extension of the central portion in the width direction of the strip S. In the case, or in the case of a so-called quarter stretched portion, which is caused by the stretch between the center portion and the both ends of the strip S in the width direction, the shape defect portion is detected from the data from the shape detection sensor, and By feedback-controlling the position of the heater board 4 based on the output value from the position detection sensor so as to match the position of each shape defect part,
It is possible to efficiently locally heat and raise the temperature of only the defective portion.

In this embodiment, in order to positively apply compressive stress to the defective shape while restraining the out-of-plane deformation of the strip S, the belt mechanism 6 is provided as a pressing mechanism below the central winding roll 3b. Is installed. The belt mechanism 6 is positioned at least above the belt mechanism 6 while guiding the steel belt 6 arranged in the longitudinal direction of the strip S, that is, the sheet passing direction of the strip S by, for example, four guide rollers 6a. Steel belt 6b
Is capable of traveling in the strip passing direction of the strip S. Then, the steel belt 6b positioned above the belt mechanism 6 is wound around the outer circumference of the central winding roll 3b with respect to the winding length of the strip S extending about 1/2 round downward. It is pressed against the outer peripheral surface of the winding roll 3b. As a result, the strip S is sandwiched between the steel belt 6b and the winding roll 3b, its out-of-plane deformation is restrained, and the defective shape portion of each steel plate is wound around the winding roll 3b and remains. Compressive stress acts on the floating portion, and the portion that extends unnecessarily is compressed. Here, in order to obtain the shape correction effect by compression, the pressing length must be set to 3 cm or more as described above, but in this embodiment, the flexible steel belt 6b is wound around the strip S. This restriction is satisfied by pressing the strip S to prevent the elongation from escaping in the longitudinal direction of the strip S, and the shape correction effect by the compression can be obtained. The steel belt 6b is also driven by rotating the guide roller 6a by an appropriate rotary drive mechanism (not shown) so that the steel belt 6b can be moved at a plate-passing speed equivalent to that of the strip S, or with the passage of the strip S. The tension applied to the strip S is reduced as much as possible so as not to affect the magnetic characteristics of the silicon steel sheet by being driven by the frictional force with the strip S, and the scratches due to the speed difference with the strip S may be generated. It must not happen.

Of course, in this embodiment as well, the heating temperature rise in the heating zone 1 or by the heater board 4 must be set to a temperature at which deformation due to creep progresses when wound around the winding rolls 3a to 3c. Needless to say. In each of the above embodiments, a local heating mechanism such as a heater board is used to locally heat the defective shape portion, but if the strip temperature in the heating zone is equal to or higher than the temperature at which deformation due to creep proceeds. And the strip is wound around the outer surface of the winding roll by the pressing mechanism.
It has been confirmed that when pressing with a pressing length of cm or more, there is a sufficient shape correcting effect without performing local heating.

In the second embodiment, the pressing is performed by the individual pressing mechanism such as the belt mechanism, but the strip temperature in the heating zone is equal to or higher than the temperature at which the deformation due to the creep progresses and the shape is appropriate. It has been confirmed that when the local heating temperature of the defective portion is raised, it is also possible to obtain a sufficient shape correcting effect by forming the winding roll with a suction roll and adsorbing the strip on the outer peripheral surface thereof. .

Although the heater heater board is used as the local heating mechanism in the above embodiment, the local heating mechanism is not limited to this. Further, the three winding rolls are arranged in a dancer roll shape, but the number of winding rolls and the arrangement state are limited to this as long as the winding angle is satisfied. is not.

[0047]

As described above, according to the method and apparatus for correcting the shape of a metal strip of the present invention, the shape correction can be completed before the entrance side of the cooling zone without applying a high tension. Therefore, it is possible to properly correct the shape of a metal band such as a strip whose characteristics are deteriorated by applying a tension like a silicon steel plate, and to effectively perform the conventional shape control in the cooling band. As a result, it is possible to improve the overall quality and yield.

[Brief description of drawings]

1A and 1B show a first embodiment of a heating zone of a horizontal continuous annealing furnace using the method and apparatus for correcting the shape of a metal strip according to the present invention, wherein (a) is a plan view and (b) is a side view. FIG. 6C is a sectional view taken along line ZZ of FIG.

2A and 2B show a second embodiment of a heating zone of a horizontal continuous annealing furnace using the method and apparatus for correcting the shape of a metal strip according to the present invention, wherein FIG. 2A is a plan view and FIG. 2B is a side view. FIG. 6C is a sectional view taken along the line YY of FIG.

FIG. 3 is a correlation explanatory view of a winding angle of a strip on a winding roll and a floating amount from a roll outer peripheral surface.

FIG. 4 is an explanatory diagram of a correlation between a steepness of a defective shape portion occurring in a strip and a floating amount from a roll outer peripheral surface.

FIG. 5 is an explanatory diagram of a correlation between roll diameter-plate thickness, residual floating-plate thickness ratio, and steepness.

FIG. 6 is an explanatory diagram showing a floating state of the strip when a pressing small-diameter roll is used.

FIG. 7 is an explanatory diagram of the correlation between the pressing length and the amount of change in the floating amount of the strip.

FIG. 8 is an explanatory view showing an example of means for applying a compressive stress to a defective shape portion while restraining out-of-plane deformation of the strip.

FIG. 9 is an explanatory view showing another example of means for applying compressive stress to a defective shape portion while restraining out-of-plane deformation of the strip.

[Explanation of symbols]

 1 is a heating zone 2 is a soaking zone 3a-3c is a winding roll 4 is a heating heater board 5 is a hydraulic cylinder 6 is a belt mechanism S is a strip (metal strip)

Claims (12)

[Claims] 1. A method of straightening the shape of a metal strip that is threaded in a horizontal continuous annealing furnace, the method comprising: winding the outer peripheral surface of a winding roll provided in the horizontal continuous annealing furnace. A method for correcting the shape of a metal band, which comprises pressing the metal band on the outer peripheral surface of the winding roll. 2. A method for straightening the shape of a metal strip that is threaded in a horizontal continuous annealing furnace, wherein a metal strip is provided on the outer peripheral surface of a winding roll provided in the horizontal continuous annealing furnace. A method for correcting the shape of a metal strip, which comprises locally heating the metal strip in a width direction by a heating means provided outside the winding roll before or during winding. 3. A method for straightening the shape of a metal strip that is threaded in a horizontal continuous annealing furnace, wherein a metal strip is provided on the outer peripheral surface of a winding roll provided in the horizontal continuous annealing furnace. Before or during winding, the heating means provided outside the winding roll locally heats the metal strip in the width direction and presses the metal strip against the outer circumferential surface of the winding roll. A method of straightening the shape of a metal band. 4. An apparatus for straightening the shape of a metal strip threaded in a horizontal continuous annealing furnace, wherein the metal strip is provided on the outer peripheral surface of a winding roll provided in the horizontal continuous annealing furnace. A shape correcting device for a metal band, comprising one or more local heating mechanisms for locally heating in the width direction of the metal band before or during winding, outside the winding roll. 5. A device for straightening the shape of a metal strip that is threaded in a horizontal continuous annealing furnace, the metal strip being wound on a winding roll provided in the horizontal continuous annealing furnace. A shape correcting device for a metal band, comprising one or more pressing mechanisms for pressing the winding roll onto the winding roll. 6. An apparatus for straightening the shape of a metal strip threaded in a horizontal continuous annealing furnace, comprising: the local heating mechanism according to claim 4; and the pressing mechanism according to claim 5. A shape correcting device for a metal band, which is characterized by arranging in parallel. 7. The local heating mechanism comprises a heater board provided outside the winding roll and movable in the width direction of the metal strip.
Alternatively, the shape correcting device for a metal strip according to Item 6. 8. The winding roll has a thickness of 1 of a metal strip.
8. The shape correcting device for a metal band according to claim 4, wherein the radius is set to 500 times or less. 9. The shape correction of a metal band according to claim 5, wherein the pressing mechanism has a pressing length of the metal band against the winding roll set to 3 cm or more per one mechanism. apparatus. 10. The shape correcting device for a metal band according to claim 5, wherein the pressing mechanism is constituted by a belt mechanism capable of traveling along the plate passing direction of the metal band. . 11. The shape correcting device for a metal strip according to claim 4, wherein the winding roll is a suction roll. 12. The shape correcting device for a metal strip according to claim 1, wherein the winding roll is installed in a heating zone in a horizontal continuous annealing furnace.