JP2000256753A - Device for adjusting roll crown of roll in furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly control the roll crown by using a induction heating device that one side of coils is arranged in the inner part of a roll in non-rotating state and the outer side of coils is arranged on the outer part of the roll as a heating means of the rolls in a furnace. SOLUTION: The heating device is constituted of the induction heating device with a transverse type coils that one side of coils A1-An is arranged in the inner part of the roll 7 in the furnace in the non-rotating state and the other side of coils B1-Bn is arranged on the outer part of the roll 7 in the furnace and the magnetic flux passes through the orthogonal direction to a roll outer shell 11 and a steel strip S surface. Since the temp. adjustment in the width direction of the roll is executed by using such a device, in the case of the quick change of the steel strip S temp. caused by change in an annealing temp., strip size and line speed, the suitable crown shape can quickly be corrected by adjusting the temp. in the roll width direction, the buckling and the meandering of the steel strip S are prevented and then, the breakage of the strip can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for adjusting a roll crown of an in-furnace roll used in a heat treatment facility of a continuous heat treatment line for metal strip.

[0002]

2. Description of the Related Art Continuous annealing equipment is installed in a continuous heat treatment line for a metal strip, for example, a continuous annealing line for a steel strip and a continuous galvanizing line. FIG. 4 shows an example of the arrangement of the main equipment of the continuous annealing equipment.

In FIG. 4, a continuous annealing equipment 1 includes a heating zone 2, a soaking zone 3, a cooling zone 4, an overaging zone 5, and a quenching zone 6. A steel strip S is provided in each of the zones 2 to 6. A number of in-furnace rolls 7 to be wound and transported are provided. The steel strip S is conveyed by a large number of in-furnace rolls 7 arranged in each of the bands 2 to 6, sequentially passes through each of the bands 2 to 6, and is subjected to a required heat treatment.

When the steel strip S is transported, deformation of the steel strip S, which is generally referred to as buckling, occurs, or the steel strip S loses its straight traveling property and meanders. In order to prevent these, the furnace roll 7 is provided with a predetermined convex roll crown.

However, in each of the in-furnace rolls 7 provided in the heating zone 2, the cooling zone 4, and the inlet to the overaging zone 5 after cooling,
Due to the large difference between the roll temperature and the temperature of the steel strip S,
The temperature in the roll width direction becomes non-uniform, causing a thermal crown, which changes the crown shape. In particular, when the strip size or the annealing temperature is changed, the change in the crown shape becomes large, the crown shape becomes inappropriate, and the strip may break due to buckling or meandering.

[0006] When the strip breaks, not only does the productivity of the continuous heat treatment line become severely impaired, but also heavy labor with danger is required for the breaking process and the like, and the equipment is damaged and the influence of the above-mentioned problems is caused. May be even larger.

[0007] When the line speed is reduced, the degree of buckling and meandering can be reduced, but the productivity is reduced, and the above problem cannot be reliably prevented. for that reason,
In order to avoid the above-mentioned situation, various proposals have been made to control the roll crown of the in-furnace roll to prevent the strip from breaking.

For example, Japanese Patent Application Laid-Open No. 53-130221 discloses that a chamber for accommodating a roll in a furnace is formed, and the temperature of the chamber is controlled by using a temperature adjusting device such as a cooling tube to reduce the roll temperature in the chamber. It has been proposed to prevent the change of the roll crown shape by adjusting the temperature substantially the same as the passing steel strip temperature and reducing the temperature difference in the roll width direction.

In Japanese Patent Publication No. 62-7249, a heat pipe in which a heat medium is sealed is provided on the outer periphery of a roll.
It has been proposed to evaporate a heat medium at a high temperature portion of the roll and condense the heat medium at a low temperature portion, thereby making the temperature in the roll width direction uniform and preventing a change in the roll crown shape.

Japanese Patent Publication No. 53-45533 discloses that
The roll has a double structure of an outer cylinder and an inner cylinder, and a coil wound around an iron core and a gas-liquid two-phase heat medium are sealed in a jacket chamber formed by the outer cylinder and the inner cylinder, and an alternating current is applied to the coil. It has been proposed to apply the applied heat to heat the heat medium and the roll outer cylinder with the generated Joule heat to make the temperature distribution of the roll outer cylinder uniform.

[0011]

In the heating zone of the continuous annealing line, when the size of the steel strip is changed, the annealing temperature is changed, and the line speed is changed, the temperature of the steel strip rapidly changes. As a result, the shape of the roll crown changes, but in order to prevent the change, it is essential that the above-mentioned roll temperature changing means has excellent responsiveness.

However, in the proposal described in Japanese Patent Application Laid-Open No. Sho 53-130221, the roll temperature is controlled by changing the temperature in the roll chamber, so that the response is poor. The effect of prevention is insufficient.

In the proposal described in Japanese Patent Publication No. 62-7249, the temperature in the roll width direction is made uniform by repeating the evaporation and condensation of the heat medium, so that the response is poor. Therefore, there is the same problem as the proposal described in Japanese Patent Application Laid-Open No. 53-130221.

In JP-B-53-45533, induction heating is performed by a so-called solenoid type coil in which magnetic flux passes in the direction along the peripheral surface of the roll outer cylinder, so that the heating efficiency is low, and there is still a problem in responsiveness. In addition, since the roll body and the induction heating device are integrated, not only does the weight of the rotating body increase, but also there is a problem in the maintainability of the roll.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an apparatus capable of rapidly controlling the roll crown of a roll in a furnace used in a heat treatment facility for a metal strip processing line in consideration of the above problems. In addition, the present invention provides a method of rolling a roll in a furnace.
An object of the present invention is to increase the range of strip sizes (thickness and width) that can be processed by the metal strip processing line by actively changing the crown.

[0016]

Means of the present invention for solving the above problems are as follows.

(1) In a device for heating a roll in a furnace of a continuous heat treatment facility to adjust a roll crown of the roll in the furnace, a heating means for the roll in the furnace includes a coil in which one of the coils is placed inside the roll in the furnace. A roll crown adjusting device for an in-furnace roll, characterized in that it is an induction heating device which is disposed for rotation and the other coil is disposed outside the in-furnace roll.

(2) In the above (1), the induction heating device is divided into a plurality in the roll width direction, and the divided induction heating devices are arranged individually or in groups so that they can be controlled. A roll crown adjusting device for an in-furnace roll.

(3) In the above (1) or (2), one coil and the other coil are disposed so as to sandwich a roll outer shell of a furnace roll and a strip wound around the furnace roll. A roll crown adjusting device for a furnace roll.

(4) In the above (1) to (3), a temperature sensor for measuring the temperature of the roll in the furnace, and a control device for adjusting the output of the induction heating device based on the temperature measured by the temperature sensor. A roll crown control device for an in-furnace roll, comprising:

(5) In the above (4), the temperature sensor is provided so as to be able to measure the temperature in the roll width direction, and the induction heating device is provided so as to be able to adjust the output in the roll width direction. Roll control device for the in-furnace roll.

(6) In the above (1) to (5), the roll shaft of the in-furnace roll is hollow, and the hollow portion of the roll shaft is
The roll shaft and a cylindrical conductive member spaced apart from the support shaft via an insulator are arranged concentrically with the hollow roll shaft, outside the support shaft supporting the coil disposed inside the roll and the support shaft. A roll crown adjusting device for an in-furnace roll, wherein current is supplied to each coil disposed inside the roll via the cylindrical conductive member.

(7) In the above (6), the inner roll has an end plate for supporting the outer shell of the inner roll on both sides, and the end plate is freely detachable from the outer shell. A roll crown adjusting device for an in-furnace roll, which is provided.

(8) In the above items (1) to (7), the roll crown adjusting device is used for introducing a continuous heat treatment facility into a heating zone, a uniform zone, a cooling zone, and a reheating zone. A roll crown adjusting device for an in-furnace roll, which is disposed at one or more of the in-furnace rolls in the introduction section.

(9) In the above (8), the induction heating device of the roll crown adjusting device installed on the roll in the furnace at the introduction part to the heating zone can heat a range from the center in the roll width direction to 500 mm in width on both sides. A roll crown adjusting device for an in-furnace roll, wherein the roll crown adjusting device is disposed in a furnace.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings.

FIGS. 1A and 1B are schematic views showing an example of a coil arrangement of an induction heating device of a roll clan adjusting device according to an embodiment of the present invention. FIG. 1A is a cross-sectional view in the roll width direction, FIG. FIG. 2 is a view showing the structure of a cylindrical conductive member, and FIG.
It is a figure explaining the control system of an induction heating apparatus, (b) is a figure showing the YY section of (a).

In FIG. 1, reference numeral 11 denotes a roll outer shell of the in-furnace roll 7, A1, A2,..., An denotes coils arranged in the roll width direction inside the roll, and B1, B2,.
The coils A1 and B1, A2 and B2,..., An and Bn are arranged outside the roll in the roll width direction. 11 and the steel strip S.

Reference numeral 13 denotes a hollow rotary shaft of the in-furnace roll 7;
Are coils A1, A2, arranged inside the furnace roll 7.
.., A supporting shaft for supporting An, which is disposed to penetrate the inside of the hollow rotary shaft 13 of the furnace roll 7. Reference numeral 14 denotes an end plate which is detachably provided at an end of the roll outer shell 11 of the furnace roll 7 with a bolt (not shown).

Reference numeral 8 denotes a cylindrical conductive member, which is disposed concentrically with the hollow rotary shaft 13 together with the support shaft 12. Further, the cylindrical conductive member 8 is provided with an insulator 15 between the support shaft 12 and the insulator 15 and a bearing 16 between the cylindrical conductive member 8 and the hollow rotary shaft 13 of the in-furnace roll 7. The support shaft 12 is
It is fixed to a support (not shown) so as not to rotate. The in-furnace roll 7 is rotatably supported by a bearing 17 disposed outside the hollow rotary shaft 13.

As shown in FIG. 2, the cylindrical conductive member 8 includes a plurality of conductive members C11, C12, C21, C22,.
, Cn2, the conductive members C11 and C12, C21 and C22,..., Cn1 and Cn2 are coils A1, A2,.
Used to energize n. The cylindrical conductive member 8 may have a double structure or a multi-layered structure as required.

In the present apparatus, the heating device arranges one of the coils in the inside of the furnace roll in a non-rotating manner as described later, and arranges the other coil outside of the inside of the furnace roll. It is composed of an induction heating device using a so-called transverse coil that passes in a direction perpendicular to the outer shell 11 and the steel strip S surface. Therefore, compared to an induction heating device using a so-called solenoid coil, the heating efficiency is high, the response is excellent, and the roll crown can be adjusted in a very short time. Especially when heating thin strips, the efficiency is much better. Further, in the case of a steel strip having a thickness of less than 1 mm, a frequency exceeding 50 KHz is required for induction heating by a solenoid coil, but a frequency coil of about 30 KHz is required for a transverse coil, so that the frequency generator can be made much cheaper.

In the present apparatus, the furnace roll 7 is rotatable, and even if the furnace roll 7 rotates, the furnace roll 7 is rotated.
Each coil A1, A of the induction heating device arranged inside
2, ..., An are non-rotating. Therefore,
The weight of the rotating body does not increase as in the case of JP-A-3-45533.

Further, the end plate 14 is used for the outer shell 1 of the roll.
Since it is detachably disposed on the roller 1, maintenance such as replacement of the roll outer shell 11 is simplified.

In FIG. 3, reference numeral 21 denotes a temperature sensor for measuring the temperature of the roll 7 in the furnace, which is arranged so as to be able to measure the temperature in the roll width direction. Reference numeral 22 denotes a control device for the induction heating device, and the coils A1 and B are arranged in the roll width direction.
1, A2 and B2,..., And An and Bn as a set, each of which can be controlled independently or as a group. The control device 22 adjusts the output of each induction heating device in the roll width direction based on the measured value of the roll width direction temperature measured by the temperature sensor 21.

When the annealing temperature, strip size, line speed, etc. are changed, the temperature in the roll width direction in the furnace changes,
The roll crown shape changes. The temperature in the roll width direction is measured by the temperature sensor 21. Based on the measured value, the output of each induction heating device in the roll width direction is adjusted to quickly equalize the temperature in the roll width direction, and the roll crown shape changes. Can be prevented.

Further, the optimum crown shape of the in-furnace roll differs depending on the strip size (thickness, width). In the device of the present invention, by adjusting the widthwise output of the induction heating device,
Since the crown shape can be positively changed, the output of the induction heating device in the roll width direction can be adjusted to adjust the crown shape to an optimum shape according to the strip size. By adjusting the crown shape to the optimum shape, strips of a size that could not be inserted due to buckling or meandering can be inserted, so the range of strip sizes (thickness and width) that can be processed can be greatly expanded Become like

Usually, the furnace roll 7 is provided with a convex crown at the center portion. However, the roll 7 may be formed into a flat shape which is easy to process and adjusted to a required crown shape by using the apparatus of the present invention. it can.

As described above, in the furnace roll disposed at the introduction portion of the reheating furnace for performing reheating after cooling, such as the heating zone, the soaking zone, the subsequent cooling zone, and the overaging zone, the roll width The temperature in the direction tends to be particularly non-uniform. It is more preferable that the crown adjusting device of the present invention be provided on a furnace roll having a large temperature difference between the strip and the furnace roll.

In the heating zone, the influence of the change in crown shape on buckling and meandering is greater in the range from the center in the roll width direction to 500 mm in width on each side. Therefore, when the crown adjustment device is installed in the furnace roll at the introduction part to the heating zone, the induction heating device of the roll crown adjustment device can heat a range of 500 mm in width from the center in the width direction of the furnace roll to both sides. It is preferable to arrange them.

In the present invention, since the temperature in the roll width direction is adjusted by using an induction heating device using a so-called transverse coil, a sharp change in the temperature of the steel strip caused by a change in the annealing temperature, a change in the strip size, a change in the line speed, or the like. At the time of change, the temperature in the roll width direction can be adjusted to quickly obtain an appropriate crown shape, so that buckling and meandering of the strip can be prevented to prevent the strip from breaking, and that the operating conditions as described above are changed. In this case, it is not necessary to lower the line speed, and a highly efficient operation can be realized.

When the crown adjusting device of the present invention is disposed on the roll in the furnace at the introduction section to the heating zone or the introduction section to the reheating zone after cooling, the heating capability of the subsequent heating zone or reheating zone is complemented. It becomes possible.

Further, the roll crown adjusting device of the present invention can be easily installed by modifying the roll in the furnace of the existing heat treatment equipment, and the present invention can be applied not only to steel strip but also to non-ferrous metal strip. The use of the device is possible. In that case, it is possible to heat the strip at a lower frequency with a non-ferrous metal strip than with a steel strip.

[0044]

EXAMPLE In the continuous annealing equipment shown in FIG. 4, an in-furnace roll equipped with a crown adjusting device of the present invention is disposed on the first (inlet side) roll immediately after reheating of the overaging zone 5. As a result of performing the annealing operation, the allowable range of the size variation of the preceding steel strip and the succeeding steel strip to be continuously charged is 100% or less as compared with before the crown adjusting device of the present invention is installed.
% And the sheet width can be increased by 20% compared to the related art. Further, conventionally, the furnace set tension (UT) was required to be 2 kg / mm ² or more, but after the crown adjusting device of the present invention was installed, the furnace set tension could be reduced to 2 kg / mm ² or less. Furthermore, even if the line speed, the annealing temperature, and the like change greatly when the weight of the charged coil is small, or the size is largely changed, it is possible to easily perform the operation without reducing the line speed. As a result, the efficiency of the continuous annealing line was improved by 10% or more.

[0045]

According to the present invention, strip size, annealing temperature,
When changing the line speed, etc., the roll crown of the roll in the furnace of the heat treatment equipment can be quickly adjusted to the appropriate shape, or the strip tension can be further reduced, so that line breakage due to buckling or meandering of the metal strip can be prevented. ,
In addition, since it is not necessary to lower the line speed to prevent the above, a decrease in productivity due to these is prevented, and a highly efficient operation can be realized.

Also, by positively changing the crown shape of the in-furnace roll, the loading restriction of the strip size caused by the buckling and meandering can be relaxed, so that the strip size (thickness) that can be loaded into the metal strip processing line can be reduced. And width) can be greatly expanded, and the allowable range of the size fluctuation of the preceding strip and the succeeding strip to be loaded continuously can be expanded. Also, even if the loading coil weight is small, the line speed is not reduced. It becomes easier to work. As a result, more efficient production can be performed.

Since the heating means is of the induction heating type using a transverse coil, the heating efficiency is higher than that of the solenoid coil induction heating method, and the equipment can be inexpensive even when processing a thin material.

Further, since the dielectric heating device has a structure separated from the furnace roll, the weight of the rotating body does not increase and the roll outer shell of the furnace roll can be easily replaced. .

[Brief description of the drawings]

FIG. 1 is a view showing an arrangement of an induction heating device in a roll width direction in a furnace.

FIG. 2 is a sectional view showing an example of the structure of a cylindrical conductive member.

FIG. 3 is a diagram illustrating a control system of the induction heating device.

FIG. 4 is a view showing an example of arrangement of main equipment of a continuous annealing equipment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Continuous annealing equipment 2 Heating zone 3 Soaking zone 4 Cooling zone 5 Overaging zone 6 Rapid cooling zone 7 Furnace roll 8 Cylindrical conductive member 11 Roll outer shell 12 Support shaft 13 Hollow rotating shaft 14 End plate 15 Insulator 16, 17 Bearing 21 Temperature sensor 22 Control device A1-An, B1-Bn Coil C11, C12, C21, C22, ..., Cn1, Cn2
Conductive member S steel strip

Continuation of the front page (72) Inventor Hisanori Eno 1-2-1 Marunouchi, Chiyoda-ku, Tokyo F-term in Nihon Kokan Co., Ltd. 4K043 AA01 DA05 EA06 GA08 GA10

Claims (9)

[Claims] 1. A device for heating a roll in a furnace of a continuous heat treatment facility to adjust a roll crown of the roll in the furnace, wherein a heating means for the roll in the furnace includes a non-rotating one coil inside the roll in the furnace. A roll crown adjusting device for an in-furnace roll, wherein the induction heating device is disposed outside the in-furnace roll and the other coil is disposed outside the in-furnace roll. 2. The apparatus according to claim 1, wherein the induction heating device is divided into a plurality of units in the roll width direction, and the divided induction heating devices are arranged individually or in a group so as to be controllable. Item 2. A roll crown adjusting device for an in-furnace roll according to item 1. 3. The coil according to claim 1, wherein the one coil and the other coil are arranged so as to sandwich a roll outer shell of the furnace roll and a strip wound around the furnace roll. Or the roll crown adjustment apparatus of the roll in a furnace of Claim 2. 4. A temperature sensor for measuring a temperature of a roll in the furnace, and based on the temperature measured by the temperature sensor,
4. The apparatus according to claim 1, further comprising a control device for adjusting an output of the induction heating device. 5. The apparatus according to claim 4, wherein the temperature sensor is arranged so as to measure the temperature in the roll width direction, and the induction heating device is arranged so as to adjust the output in the roll width direction. Roll crown control device for the roll in the furnace. 6. A roll shaft of an in-furnace roll is hollow, and a support shaft for supporting a coil disposed inside the roll is provided in a hollow portion of the roll shaft, and the roll shaft and the support shaft are provided outside the support shaft. A cylindrical conductive member separated via an insulator,
The furnace according to any one of claims 1 to 5, wherein each of the coils is disposed concentrically with a hollow roll shaft, and each coil disposed inside the roll is energized through the cylindrical conductive member. Roll crown adjustment device for rolls. 7. The furnace roll has an end plate that supports a roll shell of the furnace roll on both sides, and the end plate is provided so as to be freely attached to and detached from the roll shell. The roll crown adjusting device for an in-furnace roll according to claim 6. 8. The roll crown adjusting device may be any one or two of an introduction part to a heating zone, an introduction part to a solitary zone, an introduction part to a cooling zone, and an introduction part to a reheating zone of the continuous heat treatment equipment. 8. The roll crown adjusting device for a furnace roll according to claim 1, wherein the roll crown adjusting device is arranged on more than one furnace roll. 9. An induction heating device of a roll crown adjusting device installed on a roll in a furnace at an introduction part to a heating zone is arranged so as to be able to heat a range from a center in a roll width direction to a width of 500 mm on each side. The roll crown adjusting device for an in-furnace roll according to claim 8, wherein: