JP3738619B2 - Electromagnetic induction heating device for hot rolled steel edge - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electromagnetic induction heating device for heating a hot rolled steel material edge before being subjected to finish rolling, provided in a hot rolling facility for producing a hot rolled steel sheet, and in particular, above both hot rolled steel material edges and The present invention relates to an electromagnetic induction heating apparatus in which a through-plate guide is arranged between lower inductor coils among inductor coils provided below, and does not cause troubles of burning of the inductor coil.
[0002]
[Prior art]
The temperature of both ends in the width direction of the hot-rolled steel material, that is, both edges of the sheet bar before finish rolling is likely to be lower than that of the central portion, and the structure is formed when the portion is hot finish-rolled below the transformation point. This is a problem because it causes not only non-uniformity of the product and lowers the product yield, but also causes plate breakage or the like in the subsequent cold rolling.
[0003]
In order to solve such problems, in general, hot rolling equipment for producing hot-rolled steel sheets is provided with an electromagnetic induction heating device for hot-rolled steel edge, and the hot-rolled steel edge before finish rolling The heating is done. In the electromagnetic induction heating apparatus for hot rolled steel edges, inductor coils are provided above and below both edges of ordinary hot rolled steel, and in the width direction between the inductor coils below both hot rolled steel edges. A plate guide having a predetermined thickness is disposed.
[0004]
For example, as shown in FIGS. 3 and 4, an electromagnetic induction heating device for heating both edges of a hot rolled steel material 3 at 800 to 1100 ° C. has an upper inductor coil provided on a pair of U-shaped frames. Both edges of the hot-rolled steel material 3 are heated by an electromagnetic induction effect by the magnetic flux 10 between the 4U, 4U and the lower inductor coils 4L, 4L. The upper and lower inductor coils 4U and 4L are passed through the normal inductor coils 4U and 4L and cooled by water to prevent overheating, and are insulated and mounted in the storage units 5U and 5L, respectively. Yes.
[0005]
As shown in FIG. 3, the plate guide 1 is installed between the lower inductor coils 4L and 4L, and guides the hot rolled steel material between the table rolls 6 and 6 as shown in the side view of FIG. To do.
By the way, when the electromagnetic induction heating device is used for a certain period, the storage portions 5L and 5L of the lower inductor coils 4L and 4L are thermally deformed as shown in FIG. 6, and the scale 7 (iron oxide) of the hot rolled material is stored. There was a problem that the burning of the inductor coils 4L and 4L occurred in the part 5L.
[0006]
[Problems to be solved by the invention]
An object of the present invention is to eliminate the above-mentioned problems of the prior art, and to provide an electromagnetic induction heating device for a hot rolled steel material edge that does not cause trouble burning of an inductor coil.
[0007]
[Means for Solving the Problems]
As a result of earnestly examining the cause of the burning trouble of the inductor coil used in the hot rolling line having a bad environment, the present inventors have provided the electromagnetic induction heating device with the thermal deformation of the storage portion of the inductor coil. The present invention has been completed by finding out that the heat is generated by radiant heat from the guide plate.
[0008]
That is, the present invention according to claim 1 is an electromagnetic induction heating apparatus for heating an edge of a hot-rolled steel before being subjected to finish rolling, provided in a hot-rolling facility for producing a hot-rolled steel sheet. A hot rolled steel edge comprising an inductor coil provided above and below both edges of the steel material, and a non-magnetic material plate guide disposed between the inductor coils below the hot rolled steel material This is an electromagnetic induction heating device.
[0009]
The present invention according to claim 2 is the invention according to claim 1, wherein the passage guide made of nonmagnetic material is a hollow body made of nonmagnetic material.
According to a third aspect of the present invention, there is provided an electromagnetic induction heating apparatus for heating an edge of a hot rolled steel material before performing finish rolling, which is provided in a hot rolling facility for producing a hot rolled steel sheet. Electromagnetic induction heating of a hot-rolled steel edge, comprising an inductor coil provided above and below the edge, and a hollow plate guide disposed between the inductor coils below the hot-rolled steel material Device.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
First, the inductor coil burnout trouble provided in the electromagnetic induction heating device that heats both edges of the hot-rolled steel before the conventional finish rolling, which is the trigger of the present invention, will be described with reference to FIGS. Will be described in detail. FIG. 3 is a front view showing a configuration of a conventional electromagnetic induction heating device, and FIG. 4 is a partial cross-sectional view taken along the line AA of FIG. FIG. 5 is a side view showing a through-plate guide of a conventional electromagnetic induction heating device, and FIG. 6 is a partial cross-sectional view showing a thermal deformation example of a storage portion of an inductor coil.
[0011]
Here, 1 is a sheet guide, 3 is a hot rolled steel (sheet bar), 4U and 4L are inductor coils, 5U and 5L are storage units, 6 is a table roll, 7 is a scale, 10 is a magnetic flux, and 11 is a leak. Magnetic flux 1B is a water-cooled pipe.
As shown in FIGS. 3 and 4, the through-plate guide 1 provided in the conventional electromagnetic induction heating device is positioned so that the upper end of the through-plate guide 1 is positioned below the pass line formed by the table rolls 6 and 6. It is provided in the middle of the lower inductor coils 4L and 4L, and prevents the tip and tail ends of the hot-rolled steel material 3 from colliding with or contacting the lower inductor coils 4L and 4L. This conventional plate guide 1 is a solid body of carbon steel, has a predetermined thickness in the width direction, a predetermined length in the rolling direction, and a predetermined height, and the tip and tail ends of the hot-rolled steel material 3. It has a predetermined rigidity that does not easily deform even if it collides or contacts.
[0012]
However, a water-cooled pipe 1B is normally provided inside the through-plate guide 1 as shown in FIG. 5 so that the through-plate guide 1 is water-cooled.
However, since the through-plate guide 1 provided in the conventional electromagnetic induction heating apparatus as described above is a ferromagnetic material made of carbon steel, the upper-inductor coil shown in FIG. An eddy current is generated by the leakage magnetic flux 11 from 4U and 4U through the plate guide 1 to the lower inductor coils 4L and 4L, and the plate guide 1 is heated by Joule heat due to the eddy current.
[0013]
For this reason, the plate guide 1 is not only subjected to the radiant heat of the hot-rolled steel material 3 but also heated by electromagnetic induction by the leakage magnetic flux 11, so that it is cooled only by water cooling by the water cooling pipe 1B shown in FIG. The temperature of the sheet guide 1 has risen to a predetermined value or more due to shortage.
The storage portions 5L and 5L of the lower inductor coils 4L and 4L receive not only the radiant heat from the hot-rolled steel material 3 but also the radiant heat from the sheet guide 1, and the temperature rises, and the storage portions 5L and 5L The amount of thermal expansion has increased, and for example, thermal deformation has occurred in which one side of the corners of the storage portions 5L and 5L opens toward the plate guide 1 as shown in FIG.
[0014]
The scale 7 or the like entered from the thermally deformed portion, and the insulating properties of the inductor coils 4L and 4L were lowered, causing troubles of burning of the inductor coils 4L and 4L.
Therefore, the electromagnetic induction heating apparatus of the present invention is provided with a passage guide made of a nonmagnetic material, and preferably a passage guide of a hollow body made of a nonmagnetic material. In the present invention, by using a non-magnetic material through plate guide, the temperature rise of the through plate guide itself is suppressed, the storage portion is prevented from being deformed, the scale is prevented from entering, and the inductor coil burnout trouble is eliminated. Is.
[0015]
The threading guide used for the electromagnetic induction heating device of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a front view illustrating a configuration of an electromagnetic induction heating device according to an example of the present invention, and FIG. 2 is a side view illustrating an example of a sheet guide used in the present invention. 1 and 2, the same components as those in FIGS. 3 to 6 are denoted by the same reference numerals, and description thereof is omitted.
Here, 2 is a plate guide, 2B is a water-cooled pipe, and 2A is a space.
[0016]
The through-plate guide 2 of the example of the present invention is made of SUS304, which is a non-magnetic material, and is a hollow body provided with a space 2A communicating in the width direction as shown in FIGS. The passage guide 2 is provided with a water cooling pipe 2B as shown in FIG. 2 so that the passage guide 2 can be cooled with water.
In the example of the present invention, the through-plate guide 2 is made of a non-magnetic material. Therefore, the upper inductor coils 4U and 4U are passed through the through-plate guide 2 as shown in FIG. The leakage magnetic flux toward the inductor coils 4L and 4L can be reduced as much as possible, and the temperature rise of the through-plate guide 2 due to the electromagnetic induction effect of the leakage magnetic flux can be reduced. For this reason, the amount of radiant heat from the plate guide 2 to the storage portions 5L and 5L of the lower inductor coils 4L and 4L is reduced, the temperature rise of the storage portions 5L and 5L is reduced, and deformation due to heat can be prevented.
[0017]
Using the electromagnetic induction heating device of this example of the present invention, both edges in the width direction of the hot rolled steel material 3 at 800 to 1100 ° C. were heated while passing water through the water-cooled pipe 2B of the plate guide 2 to obtain FIG. When the electromagnetic induction heating device of the conventional example shown in FIG. 5 is used, the temperature of the passage guide 1 is 400 ° C., and the amount of radiant heat from the passage guide 1 to the storage portions 5L and 5L is large. 5L, 5L thermal deformation occurred and the scale entered the storage part 5L, causing the inductor coil to burn out. In the case of the above invention example, the temperature of the plate guide 2 was 200 ° C. Because the amount of radiant heat from the plate guide 2 to the storage parts 5L and 5L could be reduced, the electromagnetic induction heating device could be used for a long time without any trouble.
[0018]
In the present invention example, the reason why the through-plate guide 2 is preferably a hollow body provided with a space 2A communicating in the width direction is that the radiation area can be reduced without greatly reducing the rigidity of the through-plate guide 2. The amount of radiant heat from the through-plate guide 2 to the inductor coils 4L and 4L storage parts 5L and 5L can be further reduced compared with the solid case while satisfying the function of guiding the hot-finished steel 3 and the storage part 5L. This is because thermal deformation of 5 L can be prevented from occurring for a long time.
[0019]
In the example of the present invention described above, the case where the thread guide 2 is made of a nonmagnetic material has been described. However, in the present invention, the thread guide 2 is not made of a nonmagnetic material, and the shape of the thread guide is changed. It may be a hollow body.
In the present invention, when the through-plate guide 2 is a hollow body other than a non-magnetic material, the temperature rise of the through-plate guide 2 due to the electromagnetic induction effect of leakage magnetic flux cannot be reduced, but the rigidity of the through-plate guide 2 By reducing the radiation area of the through-plate guide 2 without significantly reducing the radiating heat amount of the storage portions 5L and 5L from the radiant heat amount from the through-plate guide 2 to the storage portions 5L and 5L of the inductor coils 4L and 4L is generated. This is because it can be reduced to a lesser extent.
[0020]
As the hollow body of the through-plate guide used in the present invention, a hollow body having a plurality of holes communicating in the width direction may be used.
The non-magnetic material for the thread guide used in the present invention may be an appropriate material such as SUS316, SUS316L, or SUS304.
[0021]
【The invention's effect】
According to the present invention, since the radiant heat from the plate guide to the housing portion of the inductor coil can be reduced and thermal deformation of the housing portion can be prevented, there is no scale intrusion from the outside, and there is no trouble of burning the inductor coil.
[Brief description of the drawings]
FIG. 1 is a front view showing a configuration of an electromagnetic induction heating device according to an embodiment of the present invention.
FIG. 2 is a side view showing an example of a through-plate guide used in the present invention.
FIG. 3 is a front view showing a configuration of a conventional electromagnetic induction heating device.
4 is a partial cross-sectional view taken along the line AA in FIG. 3;
FIG. 5 is a side view showing a plate guide of a conventional electromagnetic induction heating device.
FIG. 6 is a partial cross-sectional view showing a thermal deformation example of an inductor coil housing portion.
[Explanation of symbols]
1, 2 Plate guide 3 Hot rolled steel (sheet bar)
4U, 4L inductor coil
5U, 5L storage 6 table roll 7 scale
10 Magnetic flux
11 Leakage magnetic flux
1B, 2B water-cooled piping
2A space

Claims (3)

In an electromagnetic induction heating apparatus for heating a hot rolled steel material edge before finish rolling, provided in a hot rolling facility for producing a hot rolled steel sheet, an inductor provided above and below the both hot rolled steel material edges An electromagnetic induction heating apparatus for a hot rolled steel material edge, comprising a coil and a sheet guide made of a non-magnetic material disposed between an inductor coil below the hot rolled steel material. The electromagnetic induction heating device for hot-rolled steel edge according to claim 1, wherein the through-plate guide made of non-magnetic material is a hollow body made of non-magnetic material. In an electromagnetic induction heating apparatus for heating a hot rolled steel material edge before finish rolling, provided in a hot rolling facility for producing a hot rolled steel sheet, an inductor provided above and below the both hot rolled steel material edges An electromagnetic induction heating device for a hot rolled steel material edge, comprising a coil and a hollow plate guide disposed between an inductor coil below the hot rolled steel material.

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