TW200408465A - Hot rolling method and apparatus for steel strip - Google Patents

Abstract

A hot rolling method and apparatus for producing hot rolled steel strip free from variation in material properties in the width direction by making a temperature profile uniform over the entire width direction of a rough bar at a finishing mill entry side or exit side are provided, which hot rolling method of steel strip heating a rolling material while changing a temperature rise in a width direction of the rolling material so that a temperature profile in a width direction of the rolling material at the finishing mill entry side or exit side becomes uniform, for example, heating so that at least the temperature rise at a center of the rolling material in the width direction becomes greater than the temperature rises at intermediate parts between that center and the two edges in the width direction or heating so that the temperature rises at the two edges of the roughing mill in the width direction become greater than the temperature rises at the intermediate parts in the width direction of the width direction.

Description

200408465 发明 Description of the invention: [Technical field to which the invention belongs] TECHNICAL FIELD The present invention relates to a hot rolling of a steel plate, and more particularly, to a temperature in a width direction of a rough-rolled product on the inlet side of a finishing mill by a predetermined temperature. Distribution and hot rolling method and device capable of manufacturing high yield hot rolled steel plate. tPrevious technology; j Technical background · The hot rolling of the steel plate, as shown in the figure 丨, is installed in a heating furnace 丨 10 into the low-temperature flat steel billet 2 and then heated to a predetermined temperature, the reheated The flat steel blank 2 is rolled to a predetermined thickness by the roughing mill 3, and then becomes the rough rolled product 4. Then, the head and tail of the rough rolled product 4 are cut by a cutting head machine 5, and the rough rolled product is heated by an end heater 6. Both ends in the width direction of 4 are used to restore the temperature at both ends. Then, a continuous finish rolling mill 7 composed of a plurality of stands is used to finish rolling into predetermined 15 hot-rolled steel plates, and then the cooling stands on the cooling zone. 8Cool, and then take it up with reel 9. Before the finishing rolling, the rough rolling and the finished rolling are joined, and then the finishing rolling and 锿 -shaped rolling are performed. Then, as shown in FIG. 2, a low-temperature flat steel blank 2 is placed in a heating furnace 丨, And then reheated to a predetermined temperature. After the reheated flat steel blank 2 is rolled, the roughing mill 3 is rolled to a predetermined thickness, and then becomes a rough rolled product 4. It is taken by a winding box 10 and a roll 20, and then the joint cutting machine is used. 11 Cut off the front end of the rough-rolled product rolled back by the winding box. 'The rear end of the front rough-rolled product and the front end of the subsequent rough-rolled product are joined by the welding device 12, and then the rough-rolled product is heated by the end heater 6. Both ends in the width direction of the rolled product 4 are used to restore the temperature at both ends. Then, the continuous finishing rolling mill 7 composed of a plurality of stands is used to finish rolling into a predetermined hot-rolled steel sheet. The upper cooling table 8 is cooled, and then taken up by a reel 9. In the hot rolling or ring rolling step of the above-mentioned hot-rolled steel sheet, because the low-temperature flat steel billet is reheated in a heating furnace, not only the occurrence of partial heat cannot be avoided, but also because the sheet thickness of the rolled material relative to the sheet width is Since it is small, a problem of low temperature occurs at both ends of the rough piece. The lower temperature at both ends will cause the uneven temperature distribution in the width direction of the rough rolled product, which cannot have a predetermined temperature distribution, and the uneven rolling temperature will also be the cause. uw, once the distribution of the degree of universality and / JHL degree distribution of the ancestral rolling mill is uneven, in the rice rolling, the hot-rolled steel plate will produce a flange or an intermediate bulge, and also the mechanical properties of the hot-rolled 10 steel plate in the width direction, etc. Problems such as uneven material characteristics. 15

In order to prevent the above-mentioned problem caused by uneven temperature distribution in the width direction of the rough rolling product, it is known to be installed between the rough rolling mill and the finishing rolling mill. A heating device and a heater are installed to heat the rough rolling product after rough rolling by the rough rolling mill. Method. For example, in Japanese Unexamined Patent Publication No. 3_31, it is proposed to provide an electromagnetic induction heating device for heating the entire width direction of the rough rolled product between the rough rolling mill and the precision machine, and to heat both ends of the rough rolled product. The end portion is added with a test, and the width direction of the rough rolled product at the entrance side of the finishing mill is made uniform by the electromagnetic induction heating device and the end heater. Here, the electromagnetic induction heating device used is characterized in that the coil is wound on the outer periphery of the board to 'enclose the board and have a level with the board !; = field characteristics, the board surface can be concentratedly heated by heat transfer And in a fixed state, the full width can only increase the temperature uniformly. In other words, in order to reduce the burden of delay, the technology proposed above is to heat the entire width of the rough rolled product in the 6-20 200408465 electromagnetic induction heating device. At the same time, both ends are heated by an end heater. Let the width direction be the average sentence temperature distribution. However, after 'the inventor's research on the material properties in the width direction of the hot-rolled steel sheet, it was found that even if the rough-rolled product on the inlet side of the finishing mill is heated by the end heater, The temperature distribution in the width direction is uniform, and the material properties in the width direction of the steel sheet obtained after rough rolling are still dispersed. That is, the method of heating the both ends 10 in the direction of the width Φ of the shouting piece between the roughing and finishing mills uniformly and heating the both ends 10 with a lower end heater heating temperature cannot make the material properties in the width direction of the hot-rolled steel sheet. Homogenize. With regard to the original item, after conducting various experimental investigations, it was found that the reason was that the flat steel blank was heated in a heating furnace. That is, the reason is that since the heating furnace is heated in a N / JHL atmosphere, the temperature of the center of the plate thickness of the flat steel inevitably is low. This temperature distribution will exist even if the plate thickness becomes thin after rolling, so The average temperature of 15 with respect to the width direction is lower at the center and higher at the end. Since this temperature distribution does not change even if the sheet thickness becomes thin after rolling, the temperature distribution in the width direction of the upset rolled product is left-right asymmetry. Compared with the average temperature in the width direction, the center portion is lower and the end portion is higher. , The end is the lowest temperature. The reason lies in such a temperature distribution. Therefore, the problem of uniformizing the material characteristics in the width direction of the plate cannot be solved by using a heating method including an end heater or an electromagnetic induction heating device. ▲ Therefore, the object of the present invention is to provide a temperature increase amount in the plate width direction of the rough-rolled product (the temperature rise in the central low-temperature portion in the width direction is the highest), and 7 200408465 is directed to the entrance or exit side of the finishing mill, so that A method and an apparatus for hot-rolling a hot-dried steel sheet having a certain material characteristic in the width direction when the width direction of the rough-rolled product becomes a predetermined temperature distribution. In view of the foregoing, another object of the present invention is to provide a method for heating a steel plate that can heat any area in the width direction of a steel plate (steel strip) and can control the temperature distribution in the width direction of the steel plate. Furthermore, another object of the present invention is to provide a temperature distribution in the entire width direction of the rough-rolled product on the inlet side or the outlet side of the finishing mill by heating and increasing the temperature of the central low-temperature part and the low-temperature parts on both ends of the rough-rolled product. It can increase the temperature of the entire rough rolled product to reduce the load during finishing rolling, and finish rolling can be performed at a temperature that ensures the required material characteristics to produce high-yield and width-wise material characteristics that will not be dispersed Hot rolling method and device for hot rolled steel sheet. '' In addition, another object of the present invention is to provide an inlet for a finishing mill by heating 15 central low-temperature portions and low-temperature portions at both end edges of coarse and dry parts and eliminating asymmetrical temperature distribution in the width direction. The overall temperature distribution in the width direction of the rough-rolled steel on the side is uniform, and finish rolling is performed at a temperature that can ensure the characteristics to produce a high-yield and width-direction material. Rolling method and device. The inventor of 2〇 & I found that in order to obtain a hot-rolled steel sheet whose material characteristics in the width direction do not disperse, it is necessary to uniformize the temperature distribution in the width direction of the rough-rolled product on the inlet side of the finishing mill. It is caused by heating the central low temperature part of the rough rolled product with a relatively low temperature at the center of the flat steel billet when the flat steel core is heated, and at the same time, the lower temperature of the edge parts of the rough parts produced during the heating process is increased by 8 degrees. The temperature distribution in the width direction of the rough-rolled product can be uniform, and the entire width direction can be heated to ensure the finishing rolling temperature. At the same time, an AC induction heating device with excellent heating characteristics should be used as the heating device to complete the present invention. As a stamping element (semi-finished product) of a car body element such as a car, it is a special semi-finished product with different strength in the direction of visibility. When this special semi-finished product is stamped to form a body element, the mechanical properties of a predetermined portion of the body element must be different. In the past, a method of welding a plurality of steel strips into a special semi-finished product was generally used. However, in recent years, for example, after the hot-rolled steel strip is cooled in a cooling zone (ROT) by water cooling, the cooling rate in the width direction of the steel strip is changed. In addition, the mechanical properties of the steel strip in the width direction are different, and a method of manufacturing a special semi-finished product without welding (for example, Japanese Patent Application Publication No. 11-1925001 and Japanese Patent Application Publication No. 2000-11541). 4) In this method, a method and an apparatus for heating steel strips that can effectively make the difference between the width direction of the steel strips and the JDL degree different are currently required. Compared to changing the cooling rate in the width direction of the steel strip, it was found that by making the temperature difference in the width direction of the steel strip different from before rolling, a special semi-finished product with excellent mechanical properties, especially excellent hole expansion ratio and tensile properties was produced. In order to obtain a hot-rolled steel sheet whose material characteristics in the width direction do not disperse, the inventors have made the temperature distribution in the width direction of the coarse and dry parts on the entrance side of the finishing mill: homogenization is essential, so it must be caused by the flat steel blank. During the heating process, the central low temperature part of the rough rolled product with a relatively low temperature at the center of the flat steel billet is heated to increase the temperature, and in order to obtain a special semi-finished product with a different temperature difference in the width direction of the steel plate (rough dry product) before finishing rolling, Any area in the width direction of the piece plus demon 200408465 to heat up. Therefore, it was found that a piece heater composed of a plurality of AC-type induction heating devices was arranged in the length direction of the steel plate (rough rolling), and each dry-piece heater was moved in the width direction of the steel plate. There are overlapping parts (total increase in the amount of heating). Heating the rolling mill heaters for 5 revolutions can increase the temperature of any area in the width direction of the steel plate. Therefore, the temperature distribution in the width direction can be controlled. The present invention has been completed. In the hot rolling of steel in the past, the flat steel slab was heated to a predetermined temperature, and then rolled into a rough rolled product by a rough rolling mill. Before this piece is rolled by finishing rolling, the rough rolling is first performed by a cutting machine. The front and rear ends of the piece in the longitudinal direction are used as the material. The head piece is cut and dropped. One of the purposes of cutting the front and rear ends of the thick U beef is to remove the badly shaped parts of the front and rear ends of the thick milk to prevent lean and misrolling, and the other purpose is to remove the front and rear ends. Low temperature part. If the refined milk is carried out with the low-temperature portions of the front and back ends of the rough-rolled part remaining, the steel strip will crack at the low-temperature portion during finishing rolling, and scratches will be produced on the surface of the processing roller. Regardless of the flaws on the surface of the roller, the rolling of the subsequent rough rolling is carried out regardless of the rolling cycle of the roller 隹. At a certain interval, the flaws on the roller will be transferred to the product, which will become a defect on the surface of the product. In this case, in the cutting of the front and rear ends of the coarse and dry parts, usually as shown in FIG. 27, not only the miscellaneous and bad parts 215 of the front and rear parts, or the so-called fish tail part, are cut. In addition, in order to remove the lower temperature portion of the well-shaped portion extending from the poor-shape portion to the center in the longitudinal direction, it has been necessary to cut at the cutting position 219 in the past. In Japanese Patent Application Laid-Open No. 2-6002, a device for heating the ends in the direction of the width 10 200408465 of the rough-rolled product after cutting the front and rear ends of the rough-rolled product with a cutting head cutter (also (Referred to as an end heater) A method of calendering the ends in the longitudinal direction. During this heating in the longitudinal direction, the end heater with the ability to locally heat only the end in the width direction is moved to support it. When heating the front and rear ends of the rough rolled product, it is necessary to stop the rough rolled product on the conveyor belt 5 on. Therefore, when the front end portion is heated, a temperature difference between a portion in contact with the conveyance roller and a portion not in contact with each other becomes large. In addition, when the rear end portion is heated, the rough rolled product enters the finishing rolling mill, and the conveyance of the rough and dry product cannot be stopped, and the full

heating. In Japanese Patent Publication No. 1 ~ 291 () 16, it is disclosed that it is an electromagnetic type that is installed between the roughing machine 10 and the finish rolling mill, and is installed at the front and back of the material cutting machine to add margins in the width direction. Invention of induction heating device. The front and rear ends of the rough-rolled product 'before or after cutting the bad shape part by the cutting machine' are heated by the electromagnetic induction heating device without stopping the low-temperature part of the front and rear ends in the longitudinal direction. When the finishing temperature is raised to a temperature above the metamorphic iron 15 metamorphosis onset temperature, it is further refined into a hot rolled steel strip by finishing rolling. As in the past

In general, the low-temperature portion is not cut, and only the bad shape portion is removed, so that the yield does not decrease. However, at the stage before the refined milk, the temperature of the front and rear ends of the rough-rolled product decreases, the closer to the end or the rear end, the greater the temperature at the front end or the end is 200 ° C lower than the normal 20 the above. The electromagnetic induction heating device is characterized by uniform heating regardless of the width or length. The size of the heating device is determined in accordance with the maximum heating amount of the rough rolled product. To compensate for the 200t at the foremost and the last end: the above temperature decrease 'requires a huge heating device' The investment amount of the equipment will increase. Another 11 200408465-When using an induction induction heating device of a general scale, it is impossible to compensate for the temperature drop of the front and rear ends of the rough rolled product up to 2G0 ° C, and the front and rear ends other than the poor shape will be damaged. The residual temperature does not have a sufficient upper part. Therefore, the low temperature residual part must not be removed as the material head #. , 5 [within day and month] The disclosure of the invention The present invention is to provide-a kind of heating without the need to stop the coarse milk pieces, no huge investment in equipment ', and can fully make the rough and the forefront of the rough rolled parts & · The temperature of the lower end portion rises, and the present invention has been completed for the purpose of arranging the hot rolling equipment and hot rolling method for removing only the poorly shaped portion 10 as the blank piece. The gist is as follows. (1) A method for hot-rolling a steel sheet is to change the temperature increase in the sheet width direction of the rolled material on the inlet or outlet side of the finishing mill by heating so that the temperature in the sheet width direction of the rolled material has a predetermined temperature distribution. 5 (2) A method for heating a steel plate, in which a plurality of rolling material heaters arranged in the lengthwise direction of the steel plate are moved to the widthwise direction of the steel plate, and each rolling piece and the heating machine are operated to control the temperature distribution in the widthwise direction of the steel plate. . (3) A method for heating a steel plate, in which a plurality of rolled product heaters arranged in the lengthwise direction of the steel plate are moved in the widthwise direction of the steel plate, and there are overlapping portions in the lengthwise direction of the steel plate 20, by controlling 1 in the overlapping portion controls the temperature distribution in the width direction of the steel sheet. (4) A method for heating a steel plate as described in item (2) or (3), in which when a central portion in the width direction of the steel plate is concentratedly heated, a plurality of roll heaters are moved to the center in the width direction of the steel plate, Perform heating operation. 12 A method for heating a steel plate according to item (2) or (3) is to heat a plurality of rolled product heaters at a certain interval in the width direction when heating the entire width of the steel plate to perform heating operation. () A method for heating a steel sheet as described in any one of the items (1) to (3), in which the temperature distribution in the width direction of the steel sheet is measured by a width direction thermometer disposed on the upstream side of the rolling stock heater, and based on the measurement The temperature distribution determines the amount of movement of each rolling stock heater. (7) A method for heating a steel plate according to any one of items (1) to (3), which can be moved within the coil. (8) A hot-rolling device for a steel plate is a heating device for changing the heating amount in the width direction of the rolled material to be placed on the entrance side of the roughing mill in the rolling line, between the roughing mill and the roughing mill, and between the roughing mill and the roughing mill. Between finishing mills or between finishing mills and finishing mills. (9) A hot-rolling device for a steel sheet as described in item (8), wherein the heating device is capable of heating at least the temperature increase amount of the central portion in the sheet width direction of the rolled material to be greater than the central portion and the sheet width direction by two. The middle part between the ends has a larger amount of temperature rise. (10) A type of hot rolling device for a steel plate as described in item (8) or (9), wherein the heating device is capable of heating the temperature increase amount of both ends of the rolled material in the width direction of the plate to a plate The larger the amount of heating in the middle of the width direction. (11) A hot rolling device for a steel plate according to item (8), which is provided with a heating device for changing the amount of temperature rise in the width direction of the rolled material and heating only the rough rolling after rough rolling The central low-temperature part of the piece; and the one-end heater, which is used to heat the low-temperature parts of both ends of the rough rolled product. 200408465 (12)-A kind of hot milk device of steel plate as item ，, which is located on the inlet side of the milk refiner's. · A heating device is provided, which is used to change the heating amount of the rolled material ❸, Itami ; One end heater, which is used to heat the low temperature parts of both ends of the rough rolled product; and a temperature control device, which is used to 5 grasp the width temperature distribution of the rough rolled product; The device uses the maximum value of the temperature in the width direction grasped by the temperature grasping device as a reference temperature, determines the difference between the temperature at each point in the width direction and the reference temperature, and determines the amount of temperature rise at each point based on the temperature difference, so that the width The temperature in the direction has a predetermined temperature distribution; and a control device 10 is a person who operates the heating device and the end heater based on the temperature increase amount to uniformize the temperature distribution in the width direction of the rough rolled product. (13) A hot-rolling device for a steel plate as described in item (8), wherein the heating device is arranged at least two or more along the rolling line. (14) A hot-rolling device for a steel plate according to item (8), wherein the heating device 15 is an alternating-current induction heating device capable of changing the temperature increase amount in the width direction of the plate to be rolled. $ (15) —A hot rolling device for a steel plate according to item (14), wherein the AC induction heating device is at least two AC induction heating devices with different core widths and widths in the width direction. 20 (16) A hot-rolling device for a steel plate whose material characteristics do not disperse in the width direction is provided in a heating device for a steel plate provided with a flat steel billet heating furnace, a rough rolling mill, and a finishing rolling mill, and includes: an alternating-current induction heating The device can only heat the central part of the steel plate; an AC-type induction heating can be used to heat the full width of the steel plate, and the temperature of the end can be heated to be larger than that of the center 14 200408465. (17) — A hot-rolling device for a steel plate whose material characteristics in the width direction as described in item (16) do not disperse, wherein at least one of the alternating-current induction heating devices that can heat the central portion of the steel plate has a core width of 400 Within the range of ∼5, and the full width of the heatable steel plate and the temperature increase at the end portion can be heated to at least one of the AC-type induction heating devices larger than the central portion, the core width is within the range of 800 to 2500 mm. (18) A kind of hot rolling equipment configuration, which is located between the rough rolling mill and the finishing rolling mill, and is arranged in order to induce the heating of the entire width direction of the rough rolled product. The flow induction heating device and the length of the rough rolled product are cut off. Directional cutting machine for front and rear ends. (19) A hot rolling equipment configuration is arranged between a rough rolling mill and a finishing rolling mill, and a cutting machine for cutting front and rear ends of a longitudinal direction of a rough rolling product in a longitudinal direction is arranged in order and a rough rolling product for inducing heating AC-type induction heating device with all 15 bodies in the width direction. (20) A hot rolling method using a hot rolling equipment having a hot rolling equipment configuration according to the item (18) or (19), and heating the front and rear ends of the rough-rolled product by the aforementioned AC induction heating device One or both of them shall be at least lm from the end. 20 (21) The hot rolling method according to item (2G), wherein the temperature in the lower part or the lower part of the rear side of the month J of the rough part is raised by heating, and the temperature is lowered to obtain a rough Decrease in the amount of cut off of the milk piece. (22) A pure device for steel plates, which is equipped with a heating furnace for heating flat steel slabs, a thick milking machine for rough rolling flat steel slabs, and a finishing rolling mill for roughing rough rolled products after rough drying 15 200408465 It is characterized in that an alternating-current induction heating device is provided between the rough rolling mill and the finishing rolling mill, which can increase and increase the temperature of the central part of the steel plate, and is used to make the upper or lower surface or two of the AC The type induction heating device is tilted in the width and 5 degrees of the rolling line. (23) —Hot-rolling device for a type of steel plate'is a heating furnace for heating flat steel slabs, a rough rolling mill for rough rolling flat steel slabs, and a precision drying machine for finishing rolling rough-rolled parts after rough rolling. It is characterized in that a plurality of up-and-down alternating AC induction heating devices are arranged between the rough rolling mill and the fine rolling mill along the width direction of the rolling line, and the output of each of the AC induction heating devices can be adjusted. Output adjustment device. (24) —Hot rolling equipment for steel plates, which is equipped with a heating furnace for heating the flat steel slab, a rough rolling mill for rough rolling the flat steel slab, and a finishing rolling mill for finishing the rough rolled product after rough rolling. It is characterized in that an alternating-current induction heating device is arranged between the rough rolling mill and the finishing rolling mill, and the magnetic induction beam which can change in and out of the alternating-current induction heating device in the rolling line and the width direction is not provided. Shelter.

C lean application method; J The best embodiment of the invention 20 Embodiment 1 k It is known that in order to obtain a hot-rolled steel sheet having predetermined material characteristics in the width direction, for example, the material in the width direction does not disperse, it is necessary to make the The temperature distribution in the width direction of the rough rolled product is uniform. In the past, the end heaters were used to raise the temperature of the two lower ends of the rough-rolled product after rough rolling to make the temperature distribution in the width direction of the rough-rolled product uniform. However, the hot-rolled steel sheet after finishing both ends of the rough-rolled product with an end heater, and the finished hot rolled steel sheet still has a problem of dispersion of material characteristics in the width direction. Therefore, the present inventors conducted various experiments I for this reason, and found that the reason was that the flat steel billet was heated in a heating furnace. That is, since the heating furnace heats the flat steel slab in a high-temperature atmosphere, as shown in FIG. 3 (a), the heated flat steel slab 2 has a high-temperature portion μ around it. The central portion in the width direction cannot avoid the occurrence of the low-temperature portion 13. Then, the surface ^ distribution of the rough rolling mill entrance side of this flat steel blank was measured, and as shown in Fig. 3 ', the center portion of the center line (CL) is lower than the average temperature in the width direction toward the end portion. (123 °.) After rough rolling the flat steel slab with this temperature distribution into a rough-rolled product, as shown in FIG. 40, both ends of the rough-rolled product 4 are relatively large portions that are cooled down. The temperature distribution of the thick milk piece is as shown in Fig. 4 (b), and the temperature at the center of the 1 / 2-wide center line is lower than that of the average temperature in the width direction. The middle part between the end parts is higher than 6. 0, the lowest, at least from the two end parts to the end at 100 mm (1002. 0, becomes an M-shaped temperature distribution. After finishing the rolling of this temperature distribution secret, As shown in the figure), even if the plate thickness is reduced due to finish rolling, the river-shaped temperature distribution is maintained. The central part is 842t, and the middle part is the highest (865.〇, and the end is 800t.) The temperature distribution in the width direction of the flat steel blank heated by the heating furnace, the rough rolled product after rough rolling, and the steel plate on the exit side of the finish rolling are shown in Section 5 ( b), (c). The temperature distribution in the width direction in the shape of μ is shown in Fig. 6. In the conventional heat-drying method, the end portion of the rough-rolled product is heated by the end heater. The temperature distribution of the surface of the flat steel embryo in the width direction of the moon il, as shown in Figure 6, the temperature of the middle part of the central line (CL) is 120,000 ° C, and the end temperature is high. In order to compensate for the roughness after roughing The temperature of the parts is compared: After the two ends and the two ends of the rough-rolled piece are heated by the end heater, as shown in Figure 6⑻, the temperature increase amount of the part indicated by the oblique line 16 is given, and the temperature of the two ends is The second temperature is 1.56. (:. But the temperature in the central low temperature section (1 () 3rc) does not increase in the temperature distribution in the direction of visibility. This state has been judged to be the width temperature of the rough rolled product in the past.) The distribution has been homogenized. 10

After the rough-rolled products at both ends are heated by the end heater, after finishing rolling, the temperature distribution in the width direction of the rough-rolled product remains unchanged even if the plate thickness becomes thin. The width direction of the hot-rolled steel sheet at the exit side of the rough-rolling mill The temperature distribution, as shown in Fig. 6 (a), shows that the central portion has a lower average temperature than the width direction and is 842. . . In addition, when an electromagnetic induction heating device is used as a heating device for a rough rolled product, 15 pairs of rough rolled products are heated in the width direction as a whole, as shown in FIG. 7.

Figure 7 shows the wide temperature distribution of the flat steel embryo. As shown in Fig. 7 (b), the temperature distribution in the width direction of the rough-rolled product formed by the rough rolling of the flat steel billet with this temperature distribution is shown in Fig. 7 (b). ° C, end temperature is 1002t :. When this rough-rolled product is heated uniformly in the width direction by an electromagnetic induction 20 heating device, the entire body can only be heated up by a temperature increase amount shown by a diagonal line 17, the central part becomes 1046t :, the middle part becomes 106 generation, and the end part becomes ·. C. However, the temperature distribution in the width direction at this time is still a fresh temperature distribution. Therefore, the entire rough-rolled product in the width direction is heated by the electromagnetic induction heating device, and after rolling in the rough-rolling mill, as shown in Fig. 18, a hot-rolled steel sheet having an M-shaped width-direction temperature distribution is obtained. As described above, the inventors found that in the past, when a flat steel slab heated by a heating furnace was used for hot rolling, it was found that a method of heating both ends of a rough piece by an end heater during rolling, or an electromagnetic induction heating device The method of heating the width of the rough-rolled product approximately uniformly in the width direction is different from the previous idea. The temperature distribution in the width direction of the steel plate on the entrance side of the finishing mill is not necessarily uniform. problem. Then, it was found that the temperature distribution in the width direction of the rough-rolled product was uneven due to heating of the flat steel slab in a heating furnace and heat generation at the end of the pressure-delaying process, which caused the material characteristics in the width direction of the steel sheet to be dispersed. Therefore, in the present invention, in order to uniformize the temperature distribution in the width direction of the raw material on the inlet or outlet side of the finish rolling mill, the amount of temperature rise in the width direction of the plate is changed to uniformize the temperature distribution in the width direction of the rough rolled product. At this time, it is better to increase the temperature of the central low-temperature portion of the sheet width including the 1/2 width of the rough rolled product at least than the intermediate portion (including the 1/4 width and 3 / (See the injury of 4 parts), the temperature is large. Furthermore, it is preferable to use the end heater to make the low-temperature part of the two ends of the plate rabbit direction (from at least both ends to the center of the board 100 mm). The temperature increase amount is larger than the temperature increase amount in the middle of the plate width, so as to make the temperature distribution in the width direction of the rough rolled product uniform. Moreover, in the present invention, the so-called "central portion" or "central low-temperature portion" in the width direction of the rolled material, such as a rough rolled product, includes 1 / which is lower than the maximum temperature of the temperature distribution in the width direction as described above. The area of the central part of the board width at 2 wide positions. In addition, the so-called plate width "intermediate portion" refers to the maximum temperature including the temperature distribution in the width direction other than the "central portion" in the width direction, that is, the positions of 1/4 width and 3/4 width, as described above. Area. Regarding the heating device, as long as the heating temperature distribution in the width direction is large in the central portion, the heating device may be small toward the end portion. A gas heating device concentrated in the center portion in the width direction may be used. The energizing device, the energizing device of the center 4, or the center 4, can be used, but it is best to use an AC induction heating device for heating. That is, although the gas heating device is relatively inexpensive, it is easy to produce pig iron on the surface of the rough rolling. X, the electric heating device generates a fire between the rough rolled product and the electrode. As a result, the rough-flow product may have a flaw. As for the parent flow pattern induction device, it is different from the electromagnetic induction heating device. The width can be used to heat specific parts of the rough-rolled part in the width direction. Therefore, a plurality of sets of thicker-rolled parts with narrower widths are arranged along the rolling line and have narrow AC-type induction heating devices. For example, two or more When an AC-type induction plus M with a narrower core and a narrower width is used in combination, it can heat a specific part in the desired width direction. In addition, as shown in FIG. 8, the AC induction heating device 20 is configured by winding the coil 19 around the core 18. Since it can be arranged at the upper and lower positions of the steel plate 21, it is easy to operate and does not cause rough surface rolling. Defects, and because the upper surface is not excessively heated, the arrangement relationship with other equipment such as calenders and descalers will not be limited. Hereinafter, the present invention will be described with reference to the drawings. In the hot rolling apparatus shown in Fig. 1, as shown in Fig. 9 (a), between the rough rolling mill and the finishing rolling mill, an induction heating device and an end heater are arranged to become a hot rolling device. On the inlet side of the three AC induction heating devices 23, 24, and 25 with narrower core widths and narrower widths, an inlet-side width direction indicator 22 is provided, and an outlet-side width direction thermometer% is provided as the visibility. Directional temperature control device. The rough-rolled material 4 rolled by the rough-rolling mill is conveyed in a direction of an arrow by a conveying roller. The temperature distribution in the i-degree direction of the population-side width thermometer 22, + dry piece 4, and based on the width-direction temperature distribution, determine the temperature rise of the rough-rolled parts by each of the AC induction heating devices 23, 24, and 25 based on the temperature distribution in the width direction. the amount. The rough-rolled product is heated by the AC induction heating device 23 near the central low temperature portion, and then the AC induction heating device M is used to heat the middle portion near the 1/4 width including the center portion, and then the AC induction heating device 25 is used to heat the The middle part is 3/4 width near the center part. Then, the low-temperature parts at both ends of the coarse dry part (from at least the end in the width direction to the center of the 100 mm plate) are heated by the end heater 6 (larger than that in the middle part in the width direction). The above-mentioned heating temperature increase amounts are all controlled by a temperature increase amount control device. The temperature distribution in the width direction of the heated rough-rolled product was measured with an outlet-side width-direction thermometer 26. When the temperature in the width direction measured by the outlet-side width direction thermometer% is uneven, the measurement data is sent back to the AC induction heating device 23 and the end heater 6 to change and control the heating amount of each heating device with the device. Output, etc., to make the temperature distribution in the width direction of the rough rolled product uniform. Regarding the equalization of the temperature distribution in the width direction, the temperature deviation of the temperature distribution in the width direction is preferably Ot, but in the present invention, the temperature deviation in the width direction is acceptable as long as it is equal to or less than the lot. Here, the core widths of the plural induction heating devices do not have to be the same, and can be appropriately changed according to the temperature distribution in the width direction of the plate. For example, as shown in FIG. 9 (a), it is also possible to arrange induction heating devices 27 having twice the core width as the induction heating devices 24 and 25 instead of the induction heating devices 24 and 25 and the induction heating devices 23 of FIG. 200408465 A plurality of AC-type induction heating devices and end heaters do not have to be arranged in the order shown in Figs. 9 (a) and (b). However, considering the overall temperature controllability, it is better to approach each other. Furthermore, in order to accurately grasp the temperature, a width-direction thermometer, which is a 5-temperature grasping device, should be installed near the AC induction heating device as described above. However, it may be based on the furnace temperature in the heating furnace and the outlet side of the heating furnace. The actual temperature such as the temperature of the flat steel slab and the conveying conditions of the rough parts near the induction heating device (coarse milk conditions, conveying speed, time from the heating furnace to the induction heating device, etc.), after numerical calculation, the settings can grasp the communication It is also possible to use a type of induction heating device to set a temperature distribution in the width direction on the inlet side. Alternatively, a thermometer in the width direction may be provided at the exit side of the finishing mill, and the temperature distribution in the width direction at the inlet side of the AC induction heating device may also be grasped. An example of the temperature rise characteristics of the parent model induction heating device is illustrated in FIG. 15 Figures i0 (a) to (c) show the temperature rise distribution of the rough rolled product 4 when three heating devices 23, 24, and 25 are heated with the same core width. Fig. 10 is an example in which the temperature of the rough-rolled product is uniformly increased to a maximum of 40 ° C in accordance with the respective core width of the heating device. The temperature outside the core width will gradually decrease. 20 The temperature rise distribution of the temperature rise of two AC-type induction heating devices. Since the temperature rise amounts of three are added up, as shown in FIG. 10 (d), the temperature rises of the heating devices 23, 24, and 25 are respectively 28. The temperature increase amounts of, 29, and 30 overlap, forming a gentle mountain-shaped temperature increase distribution in which the temperature increase amount changes in a wide direction. Therefore, 'for example, it has a central maximum low temperature portion 1060. (:, The middle-highest temperature 22 χ 1100 C M-shaped temperature distribution of rough-rolled pieces, by the three AC-type induction heating device at the total heating amount (4〇 艽) shown in Figure 10 (e), width The central portion in the direction can be uniformly distributed to the temperature distribution of u0 (rc.) Since both end portions are heated by the end heater, the temperature can be increased in accordance with the heating amount 16 of the end heater. As a result, the temperature in the width direction of the rough rolled product The deviation is uniformized to less than 5t. As a result, the deviation of the obtained material characteristics (such as the strength TS) can be suppressed to less than 5%. In addition, the width of the core of the AC-type induction heating device with a narrow width used in the present invention should be appropriate It is within the range of 400 to 700 mm. The reason is that the typical minimum width of a hot-rolled steel sheet is 550 to 800 mm, so only the center is heated in order to suppress the heating end, so 100 to 15 is required. AC induction heating device with a width of mm. The above description is an example of uniformizing the temperature distribution in the width direction of the rough-rolled product on the entrance side of the roughing mill in order to obtain a hot-rolled steel sheet whose material is not dispersed in the width direction. In order to get at In the case of steel plates with different material properties in the wide direction, it can be achieved by applying a temperature deviation in the plate width direction according to the material characteristics in the plate width direction. Different mechanical properties, especially for special steel plates with different hole expandability and tensile properties, it is found that the temperature difference between the width direction of the steel plate before the finish rolling can be different. The hole expandability of the steel plate after the finish rolling can be achieved by the hot rolling temperature. Effective improvement: For example, a 590 MPa-class high-strength steel strip composed of C: 0.09 to 0.11%, Si: 1.30 to 1.50%, Mn: 1.25 to 1.45%, P: 0.010% or less, and S: 0.002% or less When it is suitable for automobile components such as cross members, it is mainly used to install components in the width direction of the steel belt. From the shape of the component to the center of the width of the steel coil, the tensile flange is guarded, and the width is 1/4 of the steel belt to the end. In this process, for the stretch flange processing part, the hole expansion rate of the steel strip needs to be 70% or more, and preferably 80% or more. For the extension and guarding, the steel sheet needs to be stretched. Above 31%, preferably above 34% The following is a review of the conditions for obtaining the above-mentioned mechanical properties. Figure 11 (a) is a graph showing the relationship between the hot rolling temperature (it) and the hole expansion ratio (%) of a 590 MPa high tension steel sheet, and Figure 11 (b) It is a graph showing the relationship between the hot rolling temperature α) and the tensile EL (%) of a 590 MPa high tension steel sheet. As shown in Figure 11 (a), the hole expansion ratio of the steel strip is improved with the increase of the hot rolling temperature, but As shown in Section 11 (1 ^ 囷), the elongation of the steel strip decreases in response to an increase in the hot strip temperature. That is, the hole expansion characteristics and the tensile characteristics tend to be opposite to the hot rolling temperature. Therefore, from Section 11 ( a) According to the figure, in order to increase the hole expansion ratio to 70% or more, the hot rolling temperature must be 878 ° C or more as shown by the arrow. According to Figure 11 (b), in order to make the elongation ratio reach 31 If it is more than%, it must be 86 (Γ (: below) as shown by the arrow. It can be understood that the required temperature range is different. However, in order to obtain a steel strip with both characteristics, the hot-rolling temperature should be controlled to 86 ° ~ 88 ° t: it can be obtained within a very narrow range (the range indicated by the oblique line), but the temperature is still controlled within the range Internal difficulties, and even in temperature conditions, there is still a problem that the yield is reduced due to the dispersion of the materials. In the present invention, by changing the hot rolling temperature in the width direction of the steel strip, the hot rolling temperature near the center of the steel strip width is 87 (rc or more, 1/4 width of the steel strip ~ the end is 860 ° C or less, The hot-rolling temperature conditions of heating the central part of the steel strip width by more than 20t can be easily manufactured near the center of the steel band with a hole expansion rate of 70% or more, and the 1/4 width of the steel band ~ 31% or more of the end The elongation is a special steel strip with different mechanical properties in the width direction. However, the heating device required for manufacturing steel plates with uniform material properties in the width direction and special steel plates with different material properties in the width direction, that is, the width direction of the steel plate can be arbitrarily controlled The temperature distribution, which makes the width temperature distribution uniform or effectively makes the temperature in the width direction different has not been proposed. The inventors have conducted intensive research on a heating method and a device for a steel plate that can arbitrarily control the width temperature distribution of the steel plate. It was found that a plurality of rolling stock heaters composed of an alternating-current induction heating device were arranged in the longitudinal direction (rolling line) of the steel sheet, and each rolling stock heater was moved in the width direction. By controlling the amount of overlapping part of the rolling material heater in the longitudinal direction of the steel plate, the heating operation of each rolling material heater can be used to arbitrarily control the temperature distribution in the width direction. Figure 12 (a) is shown on the steel plate. Layout of the width direction 丨 The table of the rolling stock heater and its heating amount, the 12th ⑻ ~ ⑷ are shown in the longitudinal direction of the steel plate is configured with three rolling stock heaters, so that each rolling stock heater is staggered in the width direction by a predetermined amount Diagram of the heating amount in the wide direction. As shown in Figure 12 (a), i milk heater (AC induction heating device) 22 is arranged at the center of the steel plate 21, and the width of the steel plate is heated when the dry-piece heater is heated. The heating amount distribution 23 in the direction corresponds to the mountain-shaped heating amount distribution of the width (core width) of the rolling stock heater. Three rolling stock heaters having this heating temperature characteristic are arranged in the longitudinal direction of the steel plate, and each rolling stock heater is When the width direction of the steel plate is staggered by a predetermined amount (the center of the width direction is used as a reference for the amount of movement. Also, the movement of 200408465 5 10 is also included). When all overlaps, heat the rolling stock As shown in the figure below, the heating amount distribution in the central part of the width direction of the steel plate is the most ^ Figure 12: In the middle, the dry parts are not heated, and the upper and lower sides are not heated. In the case where two dry-piece heaters move in opposite directions, reducing the overlap of the rolling stock, the temperature increase of the three dry-piece heaters will be staggered with the moving amount, as shown below. _Heart becomes the distribution of the heating amount of the mountain type with a wider width direction of the steel plate. Then, on the first page, the figure shows that the amount of movement of the two rolling heaters on the upper and lower sides is larger than that in the first figure. In the case where the overlap of the rolling stock heater is further reduced,

15 The total heating amount distribution of the three rolling mill heaters has a wider mountain-type heating amount distribution than that in Figure 12. The 12th figure is an example of a case where the milk heater is moved at a wide distance and the rolling heater has no overlap, and the entire width of the heater is heated, which is a wider mountain shape than the 12th (c) diagram. The temperature increase amount distribution is 0, and furthermore, the “moving rolling stock heater” is not limited to the downstream side, and the same temperature distribution can be achieved regardless of which rolling stock heater is moved. In the above example, three rolling stock heaters are shown, but the number of rolling stock heaters can be & the total heating amount 'and the temperature distribution of 20 in the width direction of the steel plate can be controlled with high accuracy. That is, by moving a plurality of (two or more) rolling stock heaters in the width direction of the steel plate, the temperature distribution of the steel plate in the width direction can be changed, so that any area in the width direction of the steel plate can be heated to control the width of the steel plate. Temperature Distribution. In addition, the rolling stock heater can be moved in the coil, and the rolling stock heater can combine rolling stock heaters of the same width and / or different widths.

Use after 26. Furthermore, the heating amount and the distance between the cores of the wheat rolling mill heaters can be individually changed in the coil by a plurality of rolling mill heaters, which can further improve the temperature controllability. For example, when the temperature of the central part of a steel sheet (rough-rolled product) is low, an example of using three roll heaters to improve the temperature deviation in the width direction will be described. As shown in Fig. 13 (a), the temperature distribution in the width direction of the i500mm-wide rough-rolled product is lower at the center 4 (the letter 訄 of the rc (indicated by a dotted line). To make the center of the steel plate inverse M The temperature rise 4 (rc) makes the temperature distribution k uniform in the width direction. Therefore, the temperature is increased by using three rolling stock heaters (the temperature in the slanted area is the amount of heat). The total heating amount of the three rolling stock heaters (in real terms) (Indicated by the line) must be a gentle mountain-type temperature rise distribution (inverse centigrade) of 中央 40 ° C in the center. In order to achieve this temperature rise distribution, as shown in Figure 13)), three rolling heaters The distance between the respective cores and the heating amount are the same. Two of the three rolling mill heaters (No. 1 ~ 3) with a width of 600 mm are rolled (No. 1 & No. 3). Based on the center in the width direction (the distance in the width direction of the board is 75 mm), the heating operation is performed by moving ± 15 mm. That is, in the position where the distance in the sheet width direction is 600mm to 900mm (15mm with reference to the center of the board direction), there are portions where the cores of three rolled product heaters with No. 1 to 3 overlap, and the sheet width Directional distance 45〇111111 ~ 600mm (Based on the center of the plate width direction -300 ~ 150mm) 'There are overlapping areas of the cores of the two roll heaters No. 1 and No. 2, and the plate At a distance of 750mm to 900mm in the width direction (+ 150mm to + 30mm based on the center of the board width direction), there are overlapping portions of the cores of the two dry-piece heaters No. 2 and 3. As a result, the temperature rise distribution of each of the rolling stock heaters (No. 1 to No. · 3) was staggered with a small slope, and the total temperature rise of the three units of 200408465 was 40% higher than the central portion. 〇 Mountain-shaped temperature rise distribution. The method for determining the amount of temperature rise of the steel plate is based on the difference in the width of the steel plate (rough rolled product), the amount of movement of the milk heater, and the amount of temperature rise of the rolling heater. In the computer 5, the width direction temperature distribution of the steel plate is grasped by a width direction thermometer disposed on the upstream side of the rolling stock heater. In order to heat the difference between the temperature distribution curve in the width direction of the target and the target, the computer selects the closest movement amount and temperature increase amount. The instruction instructs the electrical sequence device to set the moving amount of the rolling stock heater (the amount of overlapping part of the rolling stock heater) and the heating amount. Thereby, a predetermined amount of temperature can be raised in any area in the width direction of the steel sheet. In addition, the method for moving the rolling stock heater can be provided, for example, on a wagon that can walk on the road. The rolling stock heater can be set up and down freely, and the trolley can be moved by the driving device to move the rolling stock heater to the steel plate. Width direction. Then, by raising and lowering the upper and lower rolling stock heaters, the clearance of the milk heater can be adjusted. Embodiment 3 In the hot rolling device shown in FIG. 1, between the thick milk machine and the dryer, as shown in FIG. 18, a core with a width larger than that of the coarse and dry part 104 is provided. The AC-type induction heating device 123 and the core width are relatively thick. The AC-type induction heating device 124 having a narrow width μ has two cores with different core widths: 2 types of induction heating devices and end heaters 106, which become heat-drying devices. . An inlet-side width-direction thermometer 122 is provided on the inlet side of two AC-type induction heating devices having different core widths, and an outlet-side width-direction thermometer 125 is provided on the outlet side. The rough rolled product ι04 rolled with a rough dryer is conveyed in the direction of the arrow by a conveying roller 28. The inlet-side width direction thermometer 22 was used to measure the temperature distribution in the direction of the rough cow. Based on the temperature distribution in the width direction, the temperature was controlled by the amount of heating. . Then "Although the rough-rolled product is heated by its wide width AC-type VU set 123 to heat its full width", especially the low-temperature parts at both ends are heated by liters / dish and then only the AC-type induction heating device 124 with a narrow width is heated Central low temperature department. Then, the low-temperature portions at both ends of the rough-rolled product are heated by a wide-range AC ㈣ · When the heating temperature of the induction heating device is insufficient, if necessary, the end heating can be ordered by an additional heater 106. The temperature distribution in the width direction of the heated rough-rolled product was measured with an outlet-side width thermometer 125. When the temperature distribution in the width direction measured by the outlet-side width direction thermometer 125 is not uniform, the measurement data is sent back to the heating amount control device of the AC induction heating device to change the output of the control device to control the heating amount of each heating device. 15 makes the temperature distribution in the widthwise central portion of the rough rolled product uniform. The uniformity of the temperature distribution in the width direction is best based on the temperature deviation of the temperature distribution in the width direction. However, in the present invention, the temperature deviation of the temperature distribution in the width direction is preferably 10 ° C or lower, and preferably 5 ° C or lower. Is allowed. Narrow width and width · The arrangement order of the wide AC-type induction heating device and the end heater is not limited to 20, but considering the overall temperature controllability, it is better to approach each other. Furthermore, for accuracy, the width-wise thermometer used as a temperature control device should be installed near the AC induction heating device as described above. However, actual measurement based on the temperature in the furnace and the temperature of the flat steel slab at the exit of the furnace may also be provided. The temperature and the conditions for conveying the rough rolled product near the induction heating device (rough rolling 29 200408465 conditions, conveying speed, time from the heating furnace to the induction heating device, etc.), and the widthwise temperature of the inlet side of the AC induction heating cracking can be grasped by numerical calculation. Knife cloth device is also available. "'A thermometer in the width direction is installed on the exit side of the finishing mill to grasp the temperature in the width direction on the inlet side of the AC induction heating device. An example of the temperature rise characteristics of the AC induction heating device will be described with reference to FIG. 19. Figures 19 and 19 show the temperature rise distribution of the rough-rolled product when the rough-rolled product is heated by an alternating-current induction heating device with a column width. (1) The temperature increase distribution of the AC-type induction heating device 124 with a narrower core width than that of the rough-rolled product in Figure 18 # is shown in Figure 18. (b) The core width shown in Figure 18 is coarse-rolled. A large temperature distribution of the temperature increase amount 127 of the AC-type induction heating device 123. As shown in Fig. 19 (a), the AC-type induction heating device 124 having a narrow core width can uniformly increase the temperature of the central portion of the rough rolled product to a maximum of 40 ° C in accordance with the core width. Then, since the temperature rises by heat transfer outside the core width, the amount of temperature rise gradually decreases, and it becomes a gentle mountain-like temperature rise distribution. In addition, as shown in FIG. 19 (b), the AC induction heating device 123 with a larger core width than that of the rough rolled product can raise the temperature of the full width of the rough rolled product to a maximum of 40 ° C, and simultaneously rough rough rolling In view of the characteristic that the current at both ends of the element is increased, the temperature at both ends of · 20 to about 150 mm can be increased by a maximum of 15 ac. Therefore, as shown in Fig. 19 (c), the total temperature increase amount of the two AC-type induction heating devices 123 and 124 uniforms the temperature distribution in the width direction of the rough rolled product. Furthermore, by arranging a plurality of alternating-current induction heating devices of different widths along the rolling line and using them in combination, the temperature distribution of the roughened product can be adjusted more finely. In addition, by changing the output of the AC-type induction heating device, the heating temperature can be changed. In addition, as shown in FIG. 19 (d), the temperature rise 116 of the end of the rough rolled product caused by the end heater is as follows. If five heaters with an end width of at least 150 mm are used, The temperature can be increased up to 150 ° C. Therefore, if the heating temperature of the two ends of the AC-type induction heating device with a wide width is insufficient, as described above, the end heater can be used to additionally compensate the temperature of both ends of the heating. In addition, the width of the iron core of the AC-type induction heating device with a relatively narrow width used in the present invention is preferably within a range of 400 to 700 mm. The reason for this is that the typical minimum plate width of a hot-rolled steel sheet is 550 to 800 mm. In order to suppress heating at the ends, only the center is heated. Therefore, an AC induction heating device with a width of 100 to 150 mm is required. The width of the core of the AC induction heating device having a relatively large width is preferably within a range of 800 to 2500 mm, and particularly within a range of 800 to 2000 mm. The reason is that in order to heat the ends, an iron core with the same width as the plate width to 500 mm is necessary. Therefore, in order to heat a steel plate with a representative minimum plate width of 550 to 800 mm, it is preferable to use 800 mm. A wide AC-type induction heating device is also suitable for heating representative hot-rolled steel plates of 1500 mm to 20 2000 mm, and an AC-type induction heating device of 2500 mm should be used. Embodiment 4 As shown in FIG. 24, the heating device for heating the rough rolling 201 between the rough rolling mill 202 and the finishing rolling mill 203 during hot rolling has conventionally used electromagnetic induction heating shown in FIG. 29 The device heats the full width of the rough rolled product. Electromagnetic 31 200408465 Induction heating devices have only been found as end heaters for heating the wide ends of rough-rolled products. The electromagnetic induction heating device is used as a full-width heating device for rough-rolled products. When the device is used, the end of the rough part may overheat or the shape of the inductor may be complicated, and a large current cannot flow, which makes it difficult to use it as a large-capacity device. 5 Therefore, based on the above reasons, it is difficult to adopt the AC method as a device for heating the full width of rough rolled products. In the electromagnetic induction heating device 231, a coil 232 is arranged around the rough-rolled product 201, and iron cores 233a and 233b are arranged above and below the rough-rolled product 201. In the present invention, by using the alternating-current induction heating device 10 having this difficulty 204 as a heating device for inducing heating of the entire width direction of the rough-rolled product 201, the foremost part and the last end of the rough-rolled product 201 The temperature of the lower part rises sufficiently, and only the bad shape part can be removed as a blank piece. When using the AC induction heating device 20 shown in FIG. 23 to induce heating of the full width of 15 rough rolled products, the portion other than the rear end portion before the longitudinal direction is heated, as shown in FIG. 25 (b). The current 222 widely flows through the rough rolled product 20m, and uniformly heats the rough rolled product in the longitudinal direction. On the other hand, when the front and rear ends of the rough-rolled material pass through the heating device, for example, the 25th (magic picture shows the rough-rolled product 200m. The front end is induced by the condition of the AC-type induction heating device 204 The current 20 222 flows in the foremost portion 223, and as a result, the amount of temperature increase of the foremost portion 223 (and the last end) of the rough rolled product 1 increases due to the induced current milk. For example, the use of In the case of an alternating-current induction heating device capable of increasing the temperature of the steady part of the rolled product by 0 °, as shown by the solid line 22 in FIG. 26, the roughest rolled part is 223 (or the last end) from the foremost end. In the range of 32 mm 200408465, the temperature rise amount rises, and the temperature increase amount of more than 200 C can be obtained to the foremost part 223 (or the last part). If the heating device has the ability to raise the middle part by 6000c, As shown by the dashed line 224b in FIG. 26, the temperature increase amount of the foremost end portion 223 (or the last end portion) of the rough rolled product can exceed 400 ° C. 5 In the present invention, since the AC induction heating device 4 The entire 201 width direction of the rolled product is induced to heat. The rear end part is kept in front of the piece 201, and it is not necessary to stop the rough-rolled piece 201. By passing at the same speed as the middle portion of the rough-rolled piece 201, a large temperature rise of the front and rear ends can be obtained as described above. 10 In the first embodiment of the hot rolling equipment installation of the present invention, as shown in FIG. 24 (a), between the rough rolling mill 202 and the finishing rolling mill 203, they are arranged in order to induce AC-type induction heating device 204 for heating the entire width of the rough rolled product 201 and a cutting machine 208 that can cut the scrap pieces in the front and rear ends of the rough rolled product in the longitudinal direction.-Generally, a cutting head cutter is used for cutting. The machine is thin. In this embodiment, the front and rear ends of the rough rolled product after rough rolling are first heated by the induction heating device 204, and then the material is cut by the cutter 2 () 8. Before the rough rolling mill 202, a heating furnace 207 is arranged, and after the finisher 203, a coiling device 209 is arranged. In the second embodiment of the hot rolling equipment of the present invention, as shown in Fig. 20 and 24, Between the rough rolling mill 202 and the precision dryer 203, there are sequentially arranged cutting pieces which can cut the front and rear ends of the rough rolling in the longitudinal direction. The cutting machine 2㈣ is an alternating current induction heating device for inducing heating of the entire width direction of the rough-rolled product. The general system is the same as that described above, and a blank cutter is used as the cutting machine 208. In this embodiment, the rough After rolling, the front and rear parts of the rough and dry parts are first cut by the cutting head 208 and the feeding head, and then heated by the induction heating device. As mentioned above, the rough rolled parts by the AC-type induction heating device 204 The degree of 201 is set to μ, and the highest value is at the front end and the rear end in the long direction. Therefore, the right side can be heated after cutting the front and rear end pieces, which can make the most increase in the amount of It is not the normal part of the tablet, but is effectively used. In the first embodiment described above, when induction heating is carried out, the cutting head has not yet been cut. Therefore, when the temperature drop at the foremost end or the last end of the rough rolled product is large, the induction heating may not be sufficient. Ground compensation temperature reduction

It shape. On the other hand, in the second embodiment, since the induction heating is performed only after the material head is cut at the most appropriate position, the temperature at the most appropriate position of the heating capability of the rear end portion before the induction heating device can be lowered As a result of cutting, as compared with the first embodiment, the cutting amount of the material head can be reduced in the second embodiment. The thickness of the rough rolled product at the entrance side of the right finishing mill is very thick and the finishing reduction ratio is large in order to refine the organization, so as to improve the workability of the product. The thickness of the rough rolled product is controlled by the allowable cutting torque of the cutting machine. When it becomes thicker, by cutting the material head at a high temperature in the first embodiment, the deformation resistance is reduced due to the increase in temperature, and the cutting torque tolerance of the cutting machine is relatively increased, which can further improve the cutting edge of the product. improve. In the hot-rolling method of the present invention, one or both of the front and rear ends of the rough-rolled product are heated by an alternating-current induction heating device using a hot-rolling equipment configured with the above-mentioned first or second solid-rolling hot-rolling equipment configuration. Of the 200,408,465 from the end, at least the part below h. The reason for inductively heating the portion at 1 nm from the end portion is that the lower and lower temperature portions of the front end portion and the lower end portion of the temperature can be heated sufficiently to reduce the cutting amount of the material head. Here, the "end" of the front and rear ends of the rough-rolled part refers to the fish tail of the poorly shaped part 215 (fish tail) shown in Fig. 5 27 when heating before the material piece of the rough piece. The valley portion 216 is the position of the silk point 217. Of course, using the same AC-type induction heating device, induction heating can also be performed on the entire length of the rough rolled product in the longitudinal direction. With this method, even if the heating temperature of the flat slab before the crude milk is set to a low value, the leaning temperature can be raised to the most suitable temperature. Because of the difficulty in intermittently changing the temperature of each adjacent flat steel slab in the heating furnace, the field number is changed by several flat steel slabs. It is necessary to draw the heating furnace above the target temperature, and it is necessary to load the low temperature in the furnace into the high temperature around the material 15 = wastefully sintering the material to above the target extraction temperature, so that the fuel in the heating furnace is lost. The induction heating device is used to inductively heat the entire length of the rough-rolled piece in the * φ direction, and the low-temperature I human resources can be extracted at a low temperature. When it is pulled out, it will peel off twice on the surface of the product, and the rolling will eventually damage the aesthetics of the steel coil. In order to ensure the beautiful surface, the power for cooling the rolled steel used to cool the surface of the rolled steel can be reduced during rough rolling to finish rolling. In order to save power, or to cool the rolled products in an air-cooled manner, or to increase the number of rough rolling, in order to reduce the loss of productivity. In the hot rolling method of the present invention, the above heating is performed It is possible to increase the temperature of the lower part of the 35 * rolled part or both of them by heating, thereby 'planning the reduction of the cut amount of the rough rolled material head. 5 In the past' no When the front and rear parts of the rough parts are added in the long direction, the front part of the rough parts, in addition to the bad shape part, also cuts the lower temperature part as the material. That is, the front end of the rough parts 201 is displayed. In the 27th figure near the part 213, it used to be cut at the cutting position 219. The cutting position of the material head at the rear end of the 10-face rough-rolled product varies according to the thickness of the hot-rolled coil after rough rolling. 3 It is difficult to lower the thickness of the thin material. The lower temperature part outside the open / shaped defective part is also used as the material head. The thickness of the steel coil exceeds 3_, regardless of the state of the lower end temperature. Use the inside of the bad shape part as the cutting position. That is, in the 27th (b) diagram near the end after the rough-rolled part 201 is displayed, 15 thin materials are cut at the previous cutting position. Thick material is cut at the previous cutting position 219b. The rear-end part does not completely remove the bad shape part when removing the material head; an example of rolling and rolling under the edge K. The following is a description of the remaining shape; the rolling under the bad part is when the front end bites in and when the rear end leaves. The prolonged form and the effect of this form on the thickness of the product coil. Know that the remaining part of the 'poor shape part of the plate at the time of delivery' will be folded into two engagements when the work roller bites, resulting in the work roller. Defects. Especially when the thickness of the steel coil is thin, the defects are also large, but even if the steel is “dry”, the scratches at the low temperature end will be printed on the work roller A. It will also be printed on the work roller. Damage occurs. In addition, when the remaining part of a poorly shaped part such as a fish is large, the crotch part of the front end part suddenly hangs to the side guide plate. 36 20 200408465 The feed of the calender is applied to the calender machine and the machine. There is a wrinkle shape between them, and there is a danger that the production line needs to be stopped for a long time in order to remove them. For the reasons described above, there is a considerable risk of leaving the bad shape part when the tip is bitten. When the 5 € end is left, the bad shape part will be stretched 10 to 20 times in the rolling direction according to its predetermined reduction rate. For example, the fish-like non-intermediate part will be rolled as if it were passed through multiple machines. When the thickness of the steel coil is thin, the rolling pressure distribution caused by the uneven temperature distribution in the width direction will not restrict the rotation. A turning torque will be generated at the last end, which snakes in the width direction and contacts the side guide plate 10 and is folded inward. , And the so-called lower end problem occurs. In thin materials, the defective part may be cut off, and the production line needs to be stopped due to the exchange of the rollers. Therefore, the productivity is hindered, and the risk of the defective part remaining is very high. However, when the thickness of the steel coil is thicker (thickness of more than 3mm), the condition that the tail end becomes smaller may not occur. The reason is that because the plate is thick, it will not fold inward even if it is in contact with the side guide plate. On the contrary, due to the small reduction rate, the fish-like abnormal part in the dust spreader is shorter and the load is lower. The turning torque is small. In addition, even if the plate temperature becomes low, the plate thickness is relatively thick and it is not easy to crack. Therefore, the rear end portion may not be completely removed, and a part of it may be scrapped. However, in order to strengthen mechanical properties, etc., it is appropriate to choose ordinary steels with low tensile strength such as no alloy. In addition, after the fish part at the last end is rolled into a steel coil, the last bundling is performed. During the steel coil transfer, the picking and binding f may be loosened by the remaining part of the fish part, or may be cut off. 'The binding part in the width direction of the product should be adjusted so that the remaining part of the fish part 37 200408465 does not cross. Therefore, in a thick material having a thickness of more than 3 mm, the effect of reducing the cutting amount of the header piece cannot be obtained even if the induction heating of the present invention is performed on the rear end portion 214 of the coarse dry piece. In other words, the object of reducing the cutting amount of the 5 piece of the rough-rolled piece in the hot rolling method of the present invention is one or both of the front-end portion 213 of the rough-rolled piece and the end portion 214 after the thickness of the rough-rolled coil is 3 mm or less. . The alternating-current induction heating device 204 used in the present invention for inducing the entire width direction of the rough-rolled product to induce heating, as shown in FIG. 23, the core 205 preferably has two vertical portions 211 and one horizontal portion. The U-shaped iron 10 core 5 of 212 faces the two vertical portions 211 toward the surface of the rough rolled product 201. The width of the iron core 5 is a width that can cover the full width of the rough rolled product 1. The U-shaped iron core (2 〇5a, 205b) are relatively arranged on the upper side and the lower side of the rough-rolled product 201, and the coil 206 is wound around each vertical portion (211a, 211b). Because the coil 206 wound around the vertical portion 211 generates a magnetic field, the magnetic field is formed in the middle of the opposite two U-shaped iron cores, and forms a closed magnetic field. Since the end faces of the vertical portions 211 of the respective cores are opposite to each other, a magnetic field is generated between the two end faces. Since the rough-rolled parts are arranged between the two end faces, a magnetic field perpendicular to the surface of the rough-rolled parts is formed. Since the width of the iron core 205 has a width that can almost cover the full width of the rough rolled product 201, a magnetic field perpendicular to the rough rolled product 201 is formed across the full width of the rough rolled product 201. By passing an alternating current through the coil 206 of the winding core 205 20, the magnetic field passing through the rough rolled product 201 also becomes an alternating magnetic field ', and an eddy current as an induced current is formed in the rough rolled product. Regarding the relationship between the width of the heated rough-rolled product and the width W of the core 205, the width of the rough-rolled product is preferably wider than the width W of the core. The reason is that although the AC type induction heating device may cause the end portion (the end portion in the width direction) of the rough-rolled material to be heated 38 200408465, the core width w is narrower than that of the thick milk piece, which can be suppressed. A thirst current is generated at the terminal, which can suppress excessive heating of the terminal. Thereby, the full width of the rough-rolled product can be uniformly heated.

The space between the cores arranged on the upper and lower sides of the rough-rolled product can change the heating and heating capacity of the rough-rolled product. The narrower the interval between the cores, the larger the heating temperature of the thick milk pieces. Therefore, the interval between the cores is usually made as narrow as possible. =, In the case where the front end portion 213 of the rough-rolled part has a warped shape, the interval between the cores of the induction heating device 204 is narrower. When the front end portion of the rough-rolled part with warpage cannot enter between the cores, there may be a collision. possibility. Therefore, when the front end portion 213 of the rough rolled piece enters the induction heating device, the core gap is enlarged in advance. After the front end portion enters, the core gap is reduced to increase the heating capacity. When this correspondence is made, the distance between the cores is larger when the front end portion 213 of the rough rolled product passes, so the heating capacity of the induction heating device is lower than the heating temperature. Narrow ', so the heating and heating capacity of the induction heating device becomes higher. For example, when the end of the rough part $ passes through, the interval is 13G_, and the heating and heating capacity of the last end is 50 ° C. In the induction heating device of TC, the core interval is enlarged to 340mm when the front end of the rough rolled part passes. The heating and heating capacity of the foremost part is-when a plurality of AC induction heating devices are arranged in series, the body can be a full-width induction heating device of a group. The induction of each unit can be increased to ensure that all Necessary capacity. In the past, although it was reported that it was difficult to make the induction heating device of Valley 1, this problem can be solved by using a medium-sized heating device with several hard cloths. The width of the rough-rolled products is 39 20 200408465. There are many types from wide to narrow. The core width of each induction heating device arranged in series is set to the core that is most suitable for narrow-width rough-rolled products. When hot-rolling a large-width rough-rolled product, the full-width 5 of the rough-rolled product can be heated by moving each induction heating unit in the width direction of the rough-rolled product. Frequency at 100 ~ 500Hz In the electromagnetic induction heating device, although a frequency of 15,000 Hz is used, the depth of heating penetration is deep, and in order to prevent failure due to local heating, it is appropriate to use the AC induction heating device as described above. 100 ～ 10 500Hz 〇Embodiment 5 In order to obtain a hot-rolled steel sheet with non-dispersed material properties in the width direction, it is known that it is necessary to make the temperature distribution in the width direction of the rough-rolled product on the entrance side of the finishing mill uniform. During the rough rolling, the temperature of both ends (ends) of the rough rolled piece is lowered, and the end heater is used to raise the temperature, and the temperature distribution in the width direction of the rough rolled piece is uniform by solving the asymmetry of the left and right temperature distribution. After investigation by the inventor, it was found that the asymmetrical temperature distribution in the width direction was solved by heating both ends of the rough-rolled piece by the end heater, and the hot-rolled steel plate after the rough rolling still had material properties scattered in the width direction. Therefore, the present inventors conducted various experiments on the cause, and found out that the reason lies in the heating furnace heating the flat steel slab. That is, as shown in FIG. 30, the flat steel slab is heated. In a high-temperature atmosphere, the preheating zone 313 and the heating zone 314 are heated from the loading side in the direction of the arrow, and the homogeneous zone 315 is drawn to a predetermined temperature. The flat steel slab is heated in the flat steel slab in the heating 40 200408465 furnace. In the width direction, the heat input into the side end A is small, and the heat input into the extraction side end B is large. Then, when the extraction door is opened and pulled out by the soaking zone, it is heated to the steel embryo and installed into the side end A The temperature is higher than that of the drawn-out end B. Therefore, 'the temperature of the flat steel slab in the width direction may be different by about 20 ° C 5', as shown in Figure 31 (a), it is unavoidable that after heating The flat steel billet 3202 'is surrounded by a high temperature part 3 丨 6, and a low temperature part 3 丨 7 is generated at the center part. Then, the temperature distribution at the entrance side of the roughing mill of the flat steel billet is measured, as shown in Section 3 1 (b). As shown in the figure, relative to the average temperature in the width direction, the center of the center line (CL) is lower (1200 ° C) and higher toward the ends (1240 ° C and 1220). 〇, in the width direction of 10 is a left and right asymmetric temperature distribution. When the flat steel billet with this temperature distribution is rough-rolled into a rough-rolled piece, as shown in FIG. 32 (a), 'the two ends of the rough-rolled piece are 318, which has a relatively large temperature, so the temperature distribution of the rough-rolled piece As shown in Figure 32 (b), the center part of the center line (CL) is lower than the average temperature in the width direction (1033.〇, 15 between the center part and the end part is higher (1063 ° C & 1049). ° C), and then the end is the lowest, forming a M-shaped temperature distribution. After rough rolling of this temperature distribution, as shown in Figure 32 (c), even if the thickness of the plate changes due to finish rolling, It is thin and maintains the M-shaped temperature distribution. The center part is 842 ° C, and the highest temperature on the left middle part is (872.〇, the right middle part · Temperature is 858 ° C. 10) Induction heating device is used for rough rolling The heating device, when the induction heating device is moved in the width direction to heat the rough-rolled product, will be described with reference to Figure 33. The width temperature distribution of the flat steel billet drawn from the heating furnace is shown in Figure 33 (a). The 41-dimensional distribution of the width of the rough-rolled product after the rough rolling of the flat steel blank at this temperature distribution is shown in Fig. 33 (b), and the central low-temperature part is 1033 °. c, the maximum temperature of the left middle part is 1.063C. When the induction heating device is moved in the width direction to heat the rough rolled product, the overall temperature is only increased by 3 / litre in a liter / dish, and the central part is 1.063 ° C, the middle part on the left is 1083 ° C, and the middle part on the right is 1069 ° C. However, at this time, the temperature distribution in the width direction is still M-shaped / lid distribution. Therefore, after the induction heating device is moved, After heating the entire rough-rolled product in the wide direction in a roughing mill, as shown in Fig. 33 (c), a hot-rolled steel sheet having an M-shaped width-direction temperature distribution is obtained. As described above, the present inventor found that When the flat steel blank heated by the heating furnace was used in the past, the method of heating both ends of the rough rolled product with an end heater or moving the induction heating device in the width direction to heat the rough rolled product was similar to the past. On the contrary, the temperature distribution in the width direction of the steel plate after refined milk cannot be made uniform. Then, it was found that due to the asymmetry between the central low temperature portion of the flat steel slab heated by the heating furnace and the width temperature distribution, and the end portion of the pressure delay time Wait for the third Cause 'The temperature distribution in the width direction of the rough-rolled product is not uniform, and it is the largest cause of the dispersion of the material properties in the width direction of the steel sheet. Therefore, in the present invention, although the temperature distribution in the width direction of the rough-rolled product on the entrance side of the finishing mill is uniform. AC induction heating equipment is used to heat the central low-temperature part and the low-temperature parts of both ends of the rough rolling, but at this time, in order to solve the asymmetry of the temperature distribution in the width direction, the AC induction heating is heated by tilting heating, or If necessary, use the end heater to additionally heat the low-temperature parts at both ends and compensate to increase the temperature so that the temperature distribution in the width direction of the rough-rolled product is uniform. The distribution can be used only by heating the central portion. The AC induction heating device is different from the electromagnetic induction heating device in that it has the characteristic of heating the specific part of the width direction of the workpiece uniformly according to the core. Width. · That is, the AC-type induction heating device 5 having a narrower core width than the steel plate width has the feature that the central portion of the steel plate can be heated according to the core width. &Amp; The steel plate is full width, but it has the feature that the amount of temperature increase at the end can be larger than that of the center. Also, the AC induction heating device is characterized in that the amount of temperature rise is almost inversely proportional to the gap between the core 10 and the steel plate in theory. That is, as shown in FIG. 34, when the AC induction heating device 302 is tilted in the width direction of the steel plate (arrow direction 321), the gap (GAp) between the core of the parent flow induction heating device and the steel plate is changed, and the heating amount is changed. . For example, in the AC-type induction heating device at the position indicated by a solid line in FIG. 34 (a), one of the heating characteristics of the AC-type 15 induction heating device at an output of 20% 'is shown in FIG. 34 (b). As shown. As can be understood from Fig. 34, the smaller the gap, the larger the heating amount, and the larger the gap, the smaller the heating amount. Then, the amount of temperature rise is almost inversely proportional to the distance of the gap. Therefore, because the AC-type induction heating device can be tilted to change the gap distance, if the AC-type induction heating 20 device is tilted to heat up according to the temperature distribution in the width direction, the heating temperature in the width direction can be adjusted. Can eliminate the asymmetry of the temperature distribution in the board width direction. A plurality of AC-type induction heating devices with different core widths are arranged on the calendering line. If at least one of the AC-type induction heating devices having a narrower core width than that of the rough rolled product and at least one of the core widths are larger than the width of the rough rolled product, The No. 43 flow-type induction heating device is used in combination. When heating and heating, it can be a specific part in the width direction of the central low-temperature part and the low-temperature parts at both ends in the width direction of the rough rolling. It can also eliminate the non-uniformity of the temperature distribution in the width direction. symmetry. In addition, as shown in FIG. 8, the AC induction heating device 20 in which the coil 19 is wound on the iron core 18 is used in the upper and lower positions of the steel plate (rough-rolled product) 21. There will be no flaws on the surface, and due to its characteristics, the upper surface will not be overheated, and the distance between the calender, descaler and other equipment will not be restricted. Hereinafter, the present invention will be described with reference to the drawings. -In the hot rolling device shown in Figure 1, between the rough rolling mill and the finishing rolling mill, as shown in Figure 5, it is equipped with an iron core with a width larger than that of the thicker pieces. The 3L induction heating device 325 and An AC induction heating device 324 with a smaller core width and a smaller width of the rough rolled product. Two AC induction heating devices with different widths and tilting in the width direction of the steel plate are possible. At the same time, an end heater 306 is provided to become a hot rolling device. On the inlet side of two AC-type induction heating devices with different core widths, there is an inlet-side width direction thermometer 326, and on the outlet side, there is an outlet. ○ Seeing direction / phoenix meter 327. The rough rolled product 304 rolled by the rough rolling mill is conveyed in the direction of the arrow by a conveying roller. The width-direction temperature distribution of the rough-rolled product 4 is measured with a population-side width-direction thermometer, and the heating of each of the alternating-current induction heating devices 324 and 325 is determined based on the width-direction temperature distribution, so as to determine the thickness of the rough cow. Then, the AC-type induction heating device is tilted with a predetermined gap. Rough rolled parts are heated by the narrow AC-type induction heating device, only the central low / jnL portion is heated, and the AC-type induction heating device with a larger width is used to heat the full width of milk 200408465, but especially the low-temperature portions at both ends are heated. . Then, when the temperature of the low-temperature portions at both ends of the rough-rolled product is insufficient in the heating amount of the AC-type induction heating device 325 having a relatively large width, the end heater 306 may be used to increase the heating temperature as required. The temperature distribution in the width direction of the roughened product after heating was measured with a temperature of 5 degrees on the exit side in the width direction. When the temperature distribution in the width direction measured by the outlet-side width direction thermometer 327 is not uniform, the measurement data is transmitted back to the heating amount control device of the AC induction heating device, and the control device changes and controls the heating amount of each heating device so that The temperature distribution in the width direction of the rough-rolled products is sentenced. The heating characteristics of the AC induction heating device are described below with reference to FIG. 36. Figures 36 (a) and (b) show the temperature rise distribution of the rough-rolled products when they are heated by AC-type induction heating devices with different widths. (A) shows the temperature rise distribution of the temperature increase amount when the alternating-current induction heating device 324 whose core width is narrower than that of a rough rolled product shown in FIG. 9 is parallel (solid line) and tilted (dashed line), and (b) is a display Fig. 3 5 15 shows the temperature rise distribution of the temperature increase amount when the alternating-current induction heating device 325 with a larger core width than that of a rough rolled product is parallel (solid line) and tilted (dashed line). As shown in Fig. 36 (a), the AC-type induction heating device 324 with a small core width can increase the temperature of the central part of the rough rolled product to 40 ° C at the maximum when the distance is 200 mm in parallel and the shortest distance when tilted In places where the temperature can rise up to 53 20 ° C. Then, outside the iron core, because the temperature is raised by heat transfer, the amount of temperature increase will gradually decrease, and it will show a gentle mountain shape. As shown in Fig. 36 (b), the AC induction heating device 325 with a core width of at least the width of the rough rolled product can raise the temperature of the center of the full width of the rough rolled product to 40 ° C. The current at both ends will increase. Therefore, when the distance between the two ends is 200mm, you can raise the temperature of both ends by about 150mm to 150 ° C, and tilt it to the right with a distance of 250mm. When the left is with a distance of 150mm, the left end is the largest. The temperature can be increased by 200 ° C, and the right end can be increased by 120 ° C. Therefore, as shown in Fig. 36 (c), the total temperature increase of two AC-type induction heating devices 324 and 325 with different widths can make the temperature distribution in the width direction of the rough rolled product uniform. In addition, by arranging a plurality of AC-type induction heating devices of different widths along the rolling line and combining them, the temperature distribution distribution of the rough rolled products can be finely adjusted. Furthermore, the narrowest core width of the alternating-current induction heating device 10 used in the present invention is preferably in the range of 400 to 700 mm. The reason is that the typical minimum plate width of a hot-rolled steel sheet is 550 to 800 mm. In order to suppress end heating and heat only the center, an AC-type induction heating device with a width of 100 to 150 mm is required. In addition, the width of the iron core of the AC induction heating device having a large width is preferably within a range of 15 to 1000 to 2000 mm. The reason is that it is necessary to use a core width equal to or larger than that of a hot-rolled steel sheet having a general sheet width of 1000 to 2000 mm for heating the ends. As shown in FIG. 37 (a), the tilting device used to tilt the AC-type induction heating device in the present invention is provided with a shaft capable of tilting the AC-type induction heating device 320 suspended by a support 328. 329, and an elevator 330 is arranged at the end of the AC induction heating device. When the end of the AC induction heating device is raised and lowered by the elevator 330, the AC induction heating device can be tilted by rotating the shaft 329 as a center. In addition, if the shaft is fixed, the shaft can be rotated mechanically or electrically, and it can be tilted even if it is not supported by one side of the elevator. 46 200408465 In another example, as shown in FIG. 37 (b), the two ends of the AC induction heating device 320 are supported by two elevators 33, and the ends are raised and lowered by the elevator 33. The heating device is tilted. The AC induction heating device disposed below the plate can be tilted by the same mechanism. 5 In the examples of the present invention described above, the AC-type induction heating device is tilted as an example, but instead of tilting, the same effect can be obtained by lifting and lowering the AC-type induction heating device side by side in a wide direction. That is, as shown in FIG. 38 (a), a plurality of AC-type induction heating devices 320 are arranged side by side in the width direction, and each of them is raised and lowered by an elevator 333. The distance of each pitch is controlled by 10, and the width direction can be controlled. Heating rise overflow. In addition, an alternating-current induction heating device that is separated from the plate width direction and is provided with an iron core capable of raising and lowering is arranged above and below the rough rolling, so that the same effect can be obtained even if the iron core is raised and lowered. That is, as shown in FIG. 38 (b), the core 322 is divided into a plurality of 15 cores that can be lifted and lowered in the width direction of the board by the lifter 333, and the distance between the cores can be controlled, and the heating in the width direction can be controlled. The amount of heating. · For the elevators 330 and 331, a commonly used elevator such as a hydraulic or pneumatic piston mechanism, an elevator using a crank mechanism, or an elevator using an electric motor can be used. 20 In addition, the same effect can be obtained by arranging a plurality of AC-type induction heating devices in the width direction and changing the respective outputs. That is, as shown in FIG. 38 (c), a plurality of AC-type induction heating devices 320 are juxtaposed in the width direction, and the output control device 331 controls the respective outputs, and the heating of the respective AC-type induction heating devices 32 can be controlled. The amount of heating. 47 Alternatively, as shown in FIG. 38 (d), between the AC induction heating device and the coarse and dry parts, by using a shielding plate 332 which can change the magnetic beam, the heating of the parent flow induction heating device can be controlled. The same effect. Further, in Fig. 38 (d), the shielding plate 332 is moved in and out from the upper and lower heating devices in the longitudinal direction (reverse rolling direction) of the rough rolled product 304 of the rough rolled product 403 so as to shield the magnetic flux. It can be changed, but the shielding plate 332 may be moved in and out of the width direction of the rough rolled product. According to the hot rolling method of the present invention, significant effects can be produced, that is, the temperature distribution in the width direction of a rough-rolled product with uneven temperature distribution in the width direction before rough rolling can be made uniform, and the width direction in the wide direction after finishing rolling can be obtained. Hot rolled steel sheet with non-dispersed material properties such as mechanical properties. In addition, the hot rolling device according to the present invention can produce a remarkable effect that by using an alternating-current induction heating device, the left and right asymmetrical temperature distribution in the width direction of the rough rolled product before the finish rolling can be solved. The central low temperature portion and the low temperature portions at both ends are selectively heated to increase the temperature distribution in the width direction. EXAMPLES (Example 1) After rough rolling, a flat steel blank having a thickness of 250 mm and a width of 1250 mm was heated to 1200 ° C in a heating furnace to obtain a rough rolled product having a thickness of 30 mm. Then, the rough-rolled product is heated by three AC-type induction heating devices having a narrower width than that of the rough-rolled product as shown in FIG. 9 (a), and the temperature increase amount in the center is the largest, and then the end heater is used to end the Central heating. Then, finish rolling was performed on a finish rolling mill to produce a hot-rolled steel sheet having a thickness of 2 mm and a width of 1,250 mm. At this time, the finishing rolling speed is 1000 mpm. In order to ensure that the target temperature of the finish rolling exit 200408465 is 860 ° C, the temperature of the finishing rolling inlet side must be 110 ° C. The temperature distribution of the temperature of the finishing rolling inlet side will follow the temperature in the width direction. Distribution and heat dissipation in the longitudinal direction. This temperature reduction is compensated by 3 heating devices and end heaters. According to the width direction thermometer on the population side, the temperature distribution of the steel plate heating 胄 5 is The highest point is ^, and the coldest point at the end is 1040 ° C. With 3 AC-type induction heating devices in the center, the total maximum heating is 20t: between the center and the end. The temperature increase is smaller than the central part to solve the temperature deviation of the central part, and the end part heater is used to centrally increase the temperature of the end part by 6 (rc.) By this, the deviation of the temperature distribution in the 10 direction of the width before rolling can be uniform. As a result, a steel sheet with less material (strength) dispersion in the width direction and the long direction can be obtained. According to the hot rolling method of the present invention, the following significant effects can be produced, that is, the temperature in the width direction of the rough-rolled product before finishing rolling Uniform distribution It is possible to obtain a hot-milk steel 15 plate with non-dispersed material properties such as mechanical properties in the width direction after refined milk. X. According to the thermal pinning device of the present invention, the following significant effects can be produced, that is, because of selective heating The temperature at the center of the rough-rolled product before the warm finish rolling is low, so that the temperature distribution in the width direction can be made uniform. (Example 2) The present invention will be described in detail below with reference to the examples. 20 In hot rolling, the width is used. 3 sets of AC-type rolling mill heaters (paint, BH2, BH3) with 60mm width, will be 4 types of rough-rolled steel plates with a width of 900mm, i200mm, i500 surface, and 1800mm (Rough-rolled products) Before finishing rolling, while moving the rolling-material heater in the width direction-surface heating, a test to uniformize the temperature distribution in the width direction of the steel plate is carried out⑷ ~ (e). X, the core of the upper and lower rolling product heaters 49 The distance between 200408465 is changed in three steps, namely 1.210mm, 2.160mm, and 3.130mm. Then, the temperature increase amount and the difference in temperature increase are calculated separately. Further, in the test (e) with a width of 900mm, it is further performed Heating with additional end heaters. 5 Tests are shown in Table 1. Conditions and heating amount. As shown in Table 1, the narrower the distance between the cores of the upper and lower rolling stock heaters, the larger the difference between the heating amount and the heating amount, and the larger the overlap of the rolling heater, the heating and heating The larger the amount difference. As shown in Figure 14, three rolling heaters (BH1 to 3) are moved to the WS (work side) side or DS (Drive Side) side respectively. 17th (a) to (e) ) Shows the state in which the width direction of the rolling element heater 10 corresponding to each heating test a to e is shifted. The "heating amount" of the rolling element heater in Table 1 is as shown in Fig. 15 (a). The difference between the minimum temperature in the width direction of the front and back plates. In the same manner, as shown in Fig. 15 (b), the "temperature increase difference" in Table 1 is the temperature increase amount relative to the center of the width direction of the steel plate. 20 200408465 〔Table i〕 Movement amount (face) Leg overlap amount (mm) Heating amount (° C) Heating amount difference (° C) a BH Φ210 BH1-0 Circle 1 to BH3 All: 300 37 6 Plate width Distance ②160 Book 2 = WS150 Both Book 1 and BH2: 150 /: 4 Hi 7 900 (mm) © 130 BH3-DS150 Both BH1 and Yan 3: 150 48.: ...: 8 mm EH-1— -One b leg Φ210 BH1-0 leg 1 ~ leg 3 all: 600 41 26 plate width and heart_distance © 160 off 2 = 0 both BH1 and toilet 2: 0 51 35 1200 (face) ③ 130 BH3-0 BH1 and leg 3 Both: 0 52 40 Fine EH -... II. C BH Φ210 BH1: 0 BH1 ~ BH3 All: 300 34 34 Plate width 鉄 distance between hearts ② 160 BH2-WS150 BH1 and BH2 Both: 150 39 47 1500 (mm ) 130 BH3-DS150 BH1 and BH3: 150 40 54 nun EH-one.--D BH ① 210 Jane 1: 0 Li 1 ~ Band 3 all: 0 31 29 Board width and heart distance ② 160 BH2-WS300 BH1 and BH2 Both: 300 34 34 1800 (dirty) ③ 130 Li buckle DS300 Both BH1 and Li3: 300 36 37 round EH-one-one e dish ①210 BI1-0 BH1 ~ BH3 all: 300 37 6 plate width 间 heart distance ② 160 BM2-WS150 both BH1 and leg 2 \: 150 44! 7 900 (face) ③130 legs 34] S150 Yan 3 both: 150 48 j 8 _ EH--.......... " " " Τ '^ 30 j-

Figure 16 shows the heating amount (B Η heating amount) of the four types of steel plates after they are heated by the rolling product heater (distance between the cores of the rolling product heater = 210 mm), and then by the rolling product heater in front of the finishing mill. ) Comparison with the temperature distribution in the 5th direction of the width of the plate on the exit side of the finishing mill (comparison of heating of the rolling stock heater). As shown in Figure 16 of 200408465, after rough rolling, each steel plate has a temperature deviation of the letter M type indicated by a dashed line, but with three rolling product heaters, it is indicated by a thin solid line / The total amount of temperature rises. As a result, the temperature distribution in the width direction of the steel plate becomes almost uniform like a thick solid line. ^ 5 After finishing rolling a steel plate having this temperature distribution in the width direction, a hot-rolled steel plate with uniform material properties in the width direction of the steel plate can be obtained. According to the present invention, since any area in the width direction of the steel plate can be heated and heated, the temperature distribution in the width direction of the steel plate (rough-rolled product) can be uniformized in the hot rolling, and the material properties of the width direction of the hot-rolled steel plate can be achieved Homogenize. 10 It is also possible to intentionally make the temperature distribution in the width direction of the steel plate (rough-rolled product) different, and to make special steel plates with different material properties in the width direction after hot rolling. (Example 3) After a flat steel blank having a thickness of 250 mm and a width of 1250 mm was heated to 1200 ° C in a heating furnace, it was rough-rolled to a rough-rolled product having a thickness of 30 mm. Then, as shown in FIG. 18, 15 rough-rolled pieces are collectively heated in the width direction and at the ends of the rough-rolled piece by using an alternating-current induction heating device 123 having a width larger than that of the rough-rolled piece 104. The AC-type induction heating device 124 which is narrower than the rough rolled material 104 performs concentrated heating at the center portion, and the end heater 106 performs concentrated heating at the end portion. Then, finish rolling was performed with a finisher to produce a hot-rolled steel sheet having a thickness of 2 mm and a width of 125 mm · 20. At this time, the finishing rolling speed is 1000m / min. In order to ensure that the target temperature on the exit side of finishing rolling is 860 ° C, the temperature on the entrance side of finishing rolling must be 丨 丨 ⑼ ^. The temperature distribution of the temperature at the entrance side of the finish rolling changes due to the decrease in the temperature distribution in the width direction and the heat dissipation in the long direction. This temperature drop is compensated by two AC-type induction heaters. 52 200408465 V heating device and end heater. _ As shown in Fig. 20, the temperature distribution of the other end of the leading end W of the rough-rolled product according to the width direction thermometer on the inlet side is such that the central part works. C. The highest point is _ ° c, and the coldest point at the end is 1 () ·. With a narrow width AC type induction 5 heating device, the maximum temperature of the central portion is increased by 2 (rc (i28), the temperature deviation of the central portion is resolved, and the end portion is heated centrally by 6 (TC (129). Therefore, the temperature distribution in the width direction before rolling can be made uniform. Also, as shown in FIG. 21, the entire temperature of the middle part of the rough rolled product will decrease due to the heat dissipation relationship. According to the inlet-side width direction thermometer, The temperature distribution of the top 10 before heating is as follows: the central part 106 (^, the highest point is 110 generations, and the coldest point at the end is 100 (TC.) The AC type induction heating device with a narrow width will heat the central part up to 20 ° ( 128), solve the temperature deviation of the central part, and increase the central temperature by 20c &c; c with a wide AC induction heating device, and increase the temperature of the end by 4G ° C (13G). The temperature of the end portion is raised by 15 ° C (TC (131)). This can make the temperature distribution in the width direction before rolling even ^ 〇 · Further, as shown in Figure 22 (a), the end portion after the rough rolling, because The relationship between heat dissipation and temperature will further decrease. The temperature distribution before the heat is as follows: the central part 104 (rc, the highest point is 1060 (3, the coldest point at the 20 end is 1000 ° C.) The narrower AC-type induction heating device maximizes the central part The heating temperature is increased by 20 ° C (128) to solve the temperature deviation of the central part. The wide-type AC induction heating device is used to increase the central temperature by 40 ° C 'and increase the end temperature by 80 ° C (132). The end heater centrally raises the temperature of the end by 2 (TC (133). This allows the temperature in the width direction 53 200408465 before rolling to be uniformly distributed. The full length of the front end, middle, and rear end is simultaneously rough-rolled on the inlet side. · The temperature is 1100 ° C, and the temperature at the exit side of the finish rolling is 86 (rc. The width and length of the material (elongation difference) are small. 5 That is, the temperature difference between the exit side of the finish rolling and the finish rolling is obtained. In the relationship between the strength ts of the steel sheet, as shown in Figure 22 (b), when the temperature difference on the exit side of the finish rolling is 20, the deviation of the strength TS is 10%. Therefore, in the conventional method for heating the end portion Since the temperature in the low-temperature part of the center of the rough rolling is lower than the average temperature in the width direction by 20 ° c, The deviation of the strength Ts of the width central portion of the steel sheet is 10%, and the material properties in the width direction of 10 degrees cannot be uniformized. In contrast, in the present invention, since the temperature difference in the width direction at the exit side of the finish rolling is almost 30 ° C, The deviation of the material properties in the width direction of the obtained steel sheet is 1.5%, and the material is uniform. According to the hot rolling method of the present invention, the following significant effects can be produced, that is, the temperature distribution in the width direction of the rough-rolled product before finishing rolling can be uniformized. It can obtain 15 hot-rolled steel sheets with non-dispersed material properties such as mechanical properties in the width direction after finishing rolling. In addition, according to the hot-rolling device of the present invention, the following significant effects can be produced. The central low temperature part of the rough-rolled product before rolling can uniformize the temperature distribution in the width direction. · (Example 4) 20. An alternating-current induction heating device 204 for inducing the entire widthwise direction of a rough-rolled product as shown in FIG. 23 is arranged between the rough-rolling mill 201 and the finish-rolling mill 202. The front and rear ends of the rough-rolled product are induced to heat, and the temperature at the lower and lower temperatures is increased by the heating, thereby reviewing the reduction of the cutting amount of the head of the rough-rolled product. The AC-type induction 54 arranged between the rough rolling mill 202 and the finished rolled product 203 is reviewed when the guide heating device 204 and the head cutter 8 are arranged in this order, and when they are arranged in the reverse order. The thickness of the rough-rolled product 201 is 30 mm. The iron "interval" when the front end portion 213 of the rough rolled product 201 passes the induction heating device is 404 mm, and even if the rough rolled product 205 is warped, it can be safely passed by 34 mm, and the front end portion 13 of the rough rolled product is heated. The heating amount 24a is shown by the solid line in Fig. 4. The core interval between the normal portion of the rough rolled 201 and the rear end portion 214 when passing through the induction heating device 204 is narrow by 130 mm. The amount 224b is shown by the dashed line in Fig. 4. Regarding the front end portion 213 and the rear end portion 214 of the rough rolled product, the reference point 217 in the longitudinal direction of the rough rolled product is shown as 27 (a) (b) as the fish tail portion. The position of the valley portion 216, and the distance from the reference point 217 in the long direction is the "distance from the reference point". : In Figure 28, the & axis is the distance from the reference point, and the vertical axis is the temperature of the rough rolled product 1, (a) shows the condition of the front end 213 of the rough rolled product, and (1)) shows the rear end of the rough rolled product. Department 214 status. The decision of the cutting bait setting of the material cutting machine is based on the average value x and the standard deviation σ of the rough rolling temperature before the finishing rolling in the cutting position, and the front end portion 213 'of the rough rolling is χ_2σ is 10l. 〇t: The cutting is performed at the position of the rear end portion 214 of the rough-rolled product, and the cutting is performed at a position where χ_2σ is 924 ° C. The reason why the target temperature of the front end portion 213 is higher is that in the finishing rolling, the low temperature portion of the rough-rolled product may be cracked, and the front end portion of the rough-rolled product is more serious. First, the rough-rolled product after the rough rolling is first heated by an alternating-current induction heating device, and then the tip piece is cut by a tip cutter. Figure 28 (a) shows the rough rolled product near the front end portion 213 of the rough rolled product before rough rolling, and shows that the raw material near the rear end portion 214 of the rough rolled product does not undergo induction heating. (b) The graph is the temperature graph of the rough rolling before. In the figure, induction heating is performed. Here, when the induction heating is performed, the cutting position 218-1 performs cutting. The rough-rolled product front end portion 213 is cut at a position where the temperature of the rough-rolled product is ^ t. As shown in section 28_, when induction heating is not performed, the line is cut at a cutting position 171 mm from the reference point 217, and the relative

10 15 at 113 mm from the reference point 217. Regarding the rear end portion 14 of the rough-rolled product, the cutting is performed at a position where the χ_2σ of the rough-rolled product temperature is 924 1 and m8_ is shown. When induction heating is not performed, the cut-off position 219 is 87 mm from the reference point 217 & Cut, in contrast, when the material is heated < because the reference point 217 also heats up to χ_2σ ^ _ over 924 C of the temperature of the rough rolling / disc degree; ^ 12mm from the reference point 217 The cutting position 218a is a position that is approximately close to the reference point of the defective portion.

Then, the rough-rolled product after rough rolling is first cut by a tip cutter and then heated by an alternating-current induction heating device. After roughing the front end 213 of the rough-rolled piece at a cutting position 218-2 of 15 mm from the reference point 217, after cutting the material head, the temperature of the rough-rolling 20 pieces before the rough-rolling during induction heating is the same as that described above. 28 (a) is shown in the figure. Since the cutting is completed at the time of induction heating, a sufficient temperature rise (25 (rc) can be obtained at the cutting position 218-2 of 15mm from the reference point 217, and the result is at the cutting position 218_2 of 15111111. Rough rolling The χ-2σ of the workpiece temperature is 1010 ° C. Therefore, it can be cut at a position close to the reference portion 217 of the defective shape portion. In the first case of head cutting, a sufficient temperature increase amount is already obtained, and the same is also true when induction heating is performed after the material head is cut. The sufficient temperature increase amount is the same as in the first case. The cutting is performed at a break position 218a of 12 mmj 5 from the reference point. The present invention is to perform rough drying by arranging an alternating-current induction heating device between the rough rolling mill and the precision dryer to induce heating of the entire width of the L-piece of the rough car. Therefore, it is not necessary to stop the rough dry parts during heating, and no investment in huge equipment is required. The temperature of the lowermost part of the foremost end and the last end of the rough rolling can be sufficiently increased, and the temperature can be increased. Rough Decrease in head cutting amount. [Brief description of the drawing] Brief description of the drawing. Fig. 1 is a schematic diagram showing a conventional continuous hot rolling device. 15 Fig. 2 is a schematic diagram showing a conventional ring rolling device. Fig. 3 is a diagram illustrating a width direction of a flat steel slab reheated by a heating furnace / a knife blade. (A) is a diagram showing a low-temperature part in a thick central part of the flat steel slab, and (b) is shown in The flat part has a low temperature part in the center of the width direction. Ί〇 Figure 4 shows the width temperature distribution of the steel plate after rough rolling and finish rolling, (a) shows rough rolled parts, (b) Figure 5 shows the temperature distribution in the width direction after rough rolling, (c) shows the temperature distribution in the width direction after finishing rolling. Figure 5 shows the temperature distribution in the width direction of the steel plate after finishing rolling, and (a) shows For non-flat steel billets, (b) shows the rough rolled product, and (c) shows the temperature distribution in the width direction of the finished rolled steel plate 57 200408465. Figure 6 shows the The temperature distribution in the width direction after the end is reinforced and hot-rolled. ,. Shows the rough-rolled products heated by the end heater, and shows the temperature distribution diagram in the direction of visibility of the finished steel and 5 plates. Figure 7 shows that the rough-rolled products are heated by an electromagnetic induction heating device. The temperature distribution in the width direction after hot rolling '(a) shows a flat steel embryo, ⑼ shows a thick milk heated by an end heater, and ⑷ shows the visibility of a refined steel φ plate Temperature distribution in the direction. 10 Fig. 8 is a diagram illustrating an AC induction heating device. Fig. 9 is a diagram showing an example of an AC induction heating device configured. An example of the heating device (b) is an example in which two AC-type induction heating devices having different core widths are arranged. Figures 10 (a) to (e) are diagrams illustrating the temperature distribution in the width direction when three AC type 15 induction heating devices with the same core width are heated. Figure 11 (a) shows the relationship between the hot rolling temperature (.c) _ and the hole expansion ratio (%) of the 600 MPa high tension steel plate, and Figure 11 (b) shows the hot rolling temperature of the 600 MPa high tension steel plate (° C) and tensile EL (%). Figures 12 (a) to (e) are schematic diagrams showing the amount of temperature rise in the width direction when a plurality of rolling stock heaters are moved in the width direction of the _ 20 steel plate to heat the steel plate. Figures 13 (a) and (b) are graphs showing the temperature rise distribution in the width direction and the temperature deviation improvement in the width direction of the steel sheet when heated by the rolling stock heater. Fig. 14 is a diagram explaining the movement in the width direction of the rolling stock heater in the embodiment. Figures 15 (a) and (b) are diagrams illustrating the requirements of the temperature rise and the difference in the temperature rise when heated by the rolling stock heater in the embodiment. Figures 16 (a) to (e) are graphs showing the improvement of the temperature 5 deviation in the width direction of the steel sheet in the examples. Fig. 17 is a diagram showing a state of movement in the width direction corresponding to the heating test of (a) to (e) in the examples. Fig. 18 is a diagram showing an example in which two AC-type induction heating devices having different core widths are arranged. 10 Figure 19 is a graph showing the temperature rise distribution of an AC induction heating device and an end heater. (A) is a temperature rise distribution of a narrow AC induction heating device, and (b) is a wide width AC. (C) is a graph showing the total temperature distribution of two AC-type induction heating devices, and (d) is a graph showing the temperature distribution of an end heater. 15 FIG. 20 is a diagram illustrating a temperature distribution before rolling of a front end portion of a rough rolled product. Fig. 21 is a diagram illustrating the temperature distribution before rolling in the middle portion of the rough-rolled piece. Fig. 22 (a) is a diagram illustrating the temperature distribution before rolling in the rear end portion of the rough-rolled piece. Figure 22 (b) is a graph showing the relationship between the temperature difference on the inlet side of the finish rolling and the difference in elongation of the finish rolled steel sheet. Fig. 23 is a perspective view showing an alternating-current induction heating device according to the present invention. 59 200408465 Figure 24 (a) (b) is a schematic diagram showing the configuration of the hot rolling equipment of the present invention. Figure 25 (a) (b) is a perspective view showing the state of the induced current generated in the rough-rolled product when the AC-type induction heating device is used, and FIG. 25 (a) shows the condition near the leading end of the rough-rolled product. The figure shows the normal part (middle part)-5 condition. Fig. 26 is a graph showing the temperature rise in the vicinity of the front and rear end portions of the rough piece when an AC induction heating device is used. Figure 27⑷ shows the front end of the rough-rolled part, and Figure 27⑷ shows the cutting part near the rear end. 10. Figure 28 is a graph showing the temperature of the rough-rolled product near the front and rear ends of the rough-rolled product with and without the AC induction heating device. (B) is a graph showing the temperature of the rough-rolled product. A graph of the temperature at the back end. Fig. 29 is a perspective view showing a conventional electromagnetic induction heating device. Fig. 30 is a diagram illustrating that the flat steel slab is heated by a heating furnace, and the temperature in the width direction of the flat steel slab is asymmetric. FIG. 31 is a diagram illustrating the temperature distribution in the width direction φ of a flat steel slab reheated by a heating furnace, and is a diagram showing a low temperature portion at the center of the flat steel slab. The distribution is asymmetrical, and there is a map with a low-temperature portion in the central portion in the width direction. 20 × 32 is a graph showing the temperature distribution in the width direction of the steel sheet after rough rolling and finish rolling. It is a graph showing the thickness of the rough rolled product. It is a graph showing temperature distribution in the width direction asymmetrically after rough rolling. , ⑷ series shows the left and right asymmetric temperature distribution in the width direction after finishing rolling. Figure 33 shows the temperature distribution in the width direction after heating the rough-rolled part by the induction heating device that moves in the width direction, and after hot rolling, (a) is the temperature distribution in the width direction of the flat steel embryo, ( b) shows the temperature distribution in the width direction of the rough-rolled material which is heated by moving the induction heating device in the width direction, and shows the temperature distribution in the width direction of the steel plate after finishing rolling. Section 34 (a) (b) is a graph showing the relationship between the temperature and the temperature when the AC induction heating device is tilted and the distance is changed. Fig. 35 is a diagram showing two tiltable AC-type induction heating devices having different core widths arranged on the rolling line. Figure 36 shows the temperature rise distribution of the AC induction heating device, (a) shows the temperature rise distribution of the narrow AC induction heating device, and (b) shows the temperature rise distribution of the wider AC induction heating device (C) shows the total temperature rise distribution of two AC induction heating devices. Figure 37 (a) (b) is a diagram illustrating a tilting device of an AC induction heating device. Fig. 38 is a diagram for explaining the amount of warming in the width direction of the AC-type induction heating device. (A) shows an example when a plurality of AC-type induction heating devices juxtaposed in the width direction of the plate are raised and lowered respectively. An example of the case where the core of the AC induction heating device is divided into a plurality of pieces along the width direction of the plate and each core is raised and lowered is shown. (C) is a display showing the heating temperature of a plurality of AC induction heating devices arranged in the width direction of the plate. In the example, (d) is a view showing an example in which a shielding plate for changing the magnetic flux is provided between the AC induction heating device and the rough rolled product. [Character table of the main components of the drawing] 1 ·· Reheating furnace 2 ·· Flat steel billet 200408465 3... Rough rolling mill 4... Rough rolling 5 .. Shear head machine 6.. 7... Continuous finishing rolling mill 8... Cooling table 9... Reel 10... Winding box 11 ... joint cutting machine 12 ... welding device 13 ... low temperature part 24.. AC induction heating device 25 ··· AC-type induction heating device 26 ... Outlet-side width direction thermometer 27 .. Induction heating device 28 .. Temperature increase 29 ... Temperature increase 30. · Temperature increase 104 ... Rough rolling 106 ... End heater 116 ... · Li> Ying 122… Inlet-side width direction thermometer 123 .. AC induction heating device 124. AC induction heating device 14. High temperature part 15 ... Cooling part 16. Heating amount 17. .Heating rate 18 ··· Iron core 19… Coil 20. .. AC type induction heating device 21.. Steel plate 22... Inlet width direction thermometer 23... AC type induction heating device 125 ... Outlet width direction thermometer 126… Temperature 127… Temperature 128… Temperature 129… Temperature 130… Temperature 131… Temperature 132… Temperature 133… Temperature 201 ... Rough rolling 202 .. .Finishing mill 204. .AC induction heating device

62 200408465 205a. &Quot; Iron core 205b ... Iron core 206 ... coil 207 ... heating furnace 208 ... cutting machine 209 ... winding device 211a ... vertical portion 21 lb ... vertical portion 212 ... horizontal portion 213 ... front end portion 214 ... rear end portion 215 ... poor shape portion 216 ... fishtail valley portion 217 ... reference point 218 ... cutting position 218a ... cutting position 218-1 ... cutting position 218- 2 ... cutting position 219 ... cutting position 219a ... cutting position 219b ... cutting position 222 .. induced current 223 ... front end portion 231 ... electromagnetic induction heating device 232 ... Coil 233a. &Quot; Iron core 233b ... Iron core 302 ... Flat steel billet 304 ... Rough rolled 306 ... End heater 307 ... Exit-side width direction thermometer 313 ... Preheat zone 314 ... Heating zone 315 .. Tropical zone 316 ... South temperature section 317 ... Low temperature section 318. Cooling section 319 ... Heating temperature 320 ... AC induction heating device 321 ... Tilt core 322 ... 324 .. AC-type induction heating device 325 .. AC-type induction heating device 326 .. Inlet-side width direction thermometer 327 .. Outlet-side width direction thermometer 328 ... Support body 329 ... Shaft 330 .. Lift

63 200408465 331… elevator 332… shield 333..elevator

Claims (1)

200408465 Scope of patent application: 1. A method for hot rolling a steel plate, which heats the rolled material at the inlet or outlet side of the finishing mill, changes the temperature increase in the width direction of the rolled material, and makes the m temperature in the width direction of the rolled material. It has a predetermined temperature distribution. 5 2. —A method of heating a steel plate is to move a plurality of rolling material heaters arranged in the length direction of the steel plate to the width direction of the steel plate, and heat each rolling machine to control the temperature distribution in the width direction of the steel plate. 3. —A method for heating steel plates, which is to move a plurality of heaters arranged in the length direction of the steel plate to the width direction of the steel plate, and there are 10 overlapping portions in the length direction of the steel plate, by controlling the overlap Part of the amount to control the temperature distribution in the width direction of the steel sheet. 4. A method for heating a steel plate, such as the second or third item of the scope of patent application, when centrally heating the central portion in the width direction of the steel plate, a plurality of rolled product heaters are moved to the center in the width direction of the steel plate for heating. Running. 15 5. —A method of heating a steel plate such as the second or third item of the scope of the patent application, when heating the entire width of the steel plate, moving a plurality of roll heaters to a certain interval in the width direction φ, Perform heating operation. 6. —A kind of heating of the steel plate as described in any one of the scope of claims 1 to 3. The method is to measure the temperature in the width direction of a fixed steel plate by means of a width direction temperature measurement arranged on the upstream side of the rolling stock heater. Distribution, and based on the measured temperature distribution, the amount of movement of each rolling stock heater is determined. 7 · —A method for heating a steel plate according to any one of claims 1 to 3 of the scope of patent application, which can be moved within the coil. 8 · — A hot rolling device for steel plates is a heating device used to change the temperature of the plate width of the rolled material. 65 200408465 The heating device is arranged on the entrance side of the roughing machine in the rolling line, between the roughing mill and the roughing mill, Between rough rolling mill and finishing rolling mill or between finishing rolling mill and finishing rolling mill. 9. A hot-rolling device for a steel sheet as described in item 8 of the scope of patent application, wherein the heating device 5 is capable of heating at least the temperature increase amount of the central portion in the sheet width direction of the rolled material to be greater than that of the central portion and the sheet width direction. The amount of temperature rise in the middle portion between the two end portions is large. 10. —A kind of hot-rolling device for a steel plate, such as the item No. 8 or No. 9 of the scope of patent application, in which the heating device can heat the rolled material by 10 degrees at both ends in the width direction of the rolled material to make it into a thinner plate. The larger the amount of heating in the middle of the width direction. 11. A hot-rolling device for a steel sheet as described in item 8 of the scope of patent application, comprising: a heating device for changing the temperature increase amount in the width direction of the rolled material, and heating only the rough-rolled rough-rolled parts The central low temperature part; and one end heater, which is used to heat the low temperature parts of both ends of the rough rolling. 15 12. —A kind of hot-rolling device for a steel plate such as the item No. 8 of the scope of patent application, which is located at the entrance side of the finishing mill, and is equipped with: φ a heating device, which is used to heat the plate in the width direction of the rolled material.謇 One end heater, which is used to heat the low temperature parts of both ends of the rough rolled product; 20 and a temperature control device, which is used to grasp the temperature distribution in the width direction of the rough rolled product; Another configuration is: The determination device uses the maximum value of the widthwise temperature 66 200408465 grasped by the temperature grasping device as a reference temperature, determines the difference between the temperature at each point in the width direction and the reference temperature, and determines the amount of temperature rise at each point based on the temperature difference. A person who makes the temperature m in the wide direction a predetermined temperature distribution; and a control device that operates the heating device and the end heater 5 based on the temperature increase amount to uniformize the temperature distribution in the width direction of the rough rolled product. 13. A hot-rolling device for a steel plate such as the item No. 8 in the scope of the patent application, wherein the heating device is arranged along the rolling line with at least two units. 14. A hot-rolling device for a steel plate as claimed in item 8 of the patent application, wherein the heating device is an alternating current induction heating device capable of changing the heating amount in the width direction of the rolled material. 15. —A hot-rolling device for a steel plate such as the item No. 14 of the scope of patent application, wherein the AC induction heating device is at least two AC induction heating devices with different core widths in the width direction. 16. —A type of hot rolling device for steel plates whose material characteristics do not disperse in the width direction, 15 are those equipped with heating devices for flat steel slab heating furnaces, rough rolling mills, and finishing rolling mills, including: Lu Yi AC induction heating The device can only heat the central part of the steel plate; and an alternating-current induction heating device can heat the full width of the steel plate, and the end temperature can be heated to be larger than the central part. 20 17. —A hot-rolling device for a steel plate whose material properties in the width direction do not disperse, as described in item 16 of the scope of the patent application, wherein at least one of the alternating-current induction heating devices that can heat the central portion of the steel plate has a core width of less than Within the range of 400 to 700 mm, the full width of the heatable steel plate and the temperature rise at the end portion can be heated to at least one of the AC-type induction heating devices having a larger core width than 800 to 67 200408465 2500 mm. 18. —A type of hot rolling equipment is arranged between the rough rolling mill and the finishing mill, and an alternating-current induction heating device for inducing heating of the entire width direction of the rough rolled product and a front and rear for cutting the length of the rough rolling product are arranged in this order. The cutting of the end piece 5 breaks. 19. A hot rolling equipment configuration, which is arranged between a rough rolling mill and a finishing rolling mill, and a cutting machine for cutting the front and rear ends of the rough rolled product in the longitudinal direction and a cutting machine for inducing heating of the rough rolled product are arranged in this order. AC-type induction heating device for the entire width. 10 20. —A hot rolling method using hot rolling equipment having the hot rolling equipment configuration of the item (18) or (19), and heating the front and rear ends of the rough-rolled product by the aforementioned alternating-current induction heating device. One or both of the parts shall be at least lm from the end. 21. The hot rolling method according to the scope of patent application No. 20, wherein the temperature of the lower and lower parts of one or both of the front and rear ends of the rough 15-rolled product is increased by heating, thereby seeking the Reduction of the cutting amount of the material head. φ 22. —Hot-rolling device for steel plates, which is equipped with a heating furnace for heating flat steel slabs, a rough rolling mill for rough rolling flat steel slabs, and a finishing rolling mill for finishing rolling of rough rolled products after rough rolling. It is characterized in that an alternating-current induction heating device is provided between the rough rolling mill and the finishing rolling mill, which can increase the amount of heating of the central part of the steel plate, and the upper and lower sides, or two of the alternating currents, are provided. The type induction heating device is tilted in the width direction of the rolling line. 23. —Hot rolling equipment for steel plates, which is equipped with a heating furnace for heating flat steel slabs, a rough rolling mill for rough rolling flat steel slabs, and a finishing rolling mill for rough rolling of rough rolled products after rough rolling 68 200408465 Among them, it is characterized in that a plurality of up-and-down alternating-current induction heating m devices are arranged between the rough rolling mill and the finishing rolling mill along the width direction of the rolling line, and the output of each of the alternating-current induction heating devices can be adjusted. Adjust η to adjust the device. 5 24. —Hot-rolling device for steel plates, which is equipped with a heating furnace for heating flat steel slabs, a rough rolling mill for rough rolling flat steel slabs, and a finishing rolling mill for finishing rolling of rough rolled products after rough rolling. It is characterized in that an alternating-current induction heating device is arranged between the rough rolling mill and the finishing rolling mill, and an inward and outward shielding is provided to change the magnetic beam of the alternating-current induction heating device in the width direction of the rolling line. 10 body 0 69