Technical field
[0001]
　The present invention, after the finish rolling of a continuous hot rolling process, to a method and apparatus for cooling a hot rolled steel sheet.
BACKGROUND
[0002]
　Hot-rolled steel sheet after finish rolling of a continuous hot rolling process, finishing in the run-out table which is installed between the time take-up device from the rolling mill, for example, a predetermined temperature by providing its dependent cooling system and below the ROT after being cooled to be wound around the winding device. In hot rolling the hot-rolled steel sheet, the mechanical properties of the cooling ability hot rolled steel sheet after the finish rolling, workability, has become an important factor that determines the like weldability, uniform predetermined hot-rolled steel sheet It has become important to be cooled to the temperature.
[0003]
　Therefore, conventionally, relates cool the hot rolled steel sheet, various methods and devices have been proposed.
[0004]
　Patent Document 1, a method for cooling a hot-rolled steel strip after hot rolling in contact with the coolant, and a first cooling step and a second cooling step subsequent thereto, the first cooling in the process, stop the cooling at high strip temperature than the transition boiling initiation temperature in the subsequent second cooling step, it has been proposed to cool the cooling water of the water density of the nucleate boiling. Further, in the second cooling step, it has been proposed to cool at least the steel strip top by laminar cooling or jet cooling. Further, in the secondary cooling step, and an injection nozzle for spraying high-pressure fluid to the steel strip top by draining means such as rolls arranged in the width direction of the steel strip top, to discharge the cooling water injection in the steel strip top it has also been proposed.
[0005]
　Patent Document 2, a transport line with a table rollers for conveying the steel plate is rolled from the rolling mill to the hot straightener and feed 該搬 water spray device for spraying water on both surfaces of the steel plate line along the apparatus for manufacturing a steel plate which is disposed on the upper and lower, upstream of the hot straightener conveying line, along both sides of the outer conveyor line, arranging a plurality of cooling nozzles spraying water it has been proposed to provide a delivery side of the rolling mill water spray apparatus.
[0006]
　Patent Document 3, the cooling device for injecting cooling water on the upper surface of the hot-rolled steel sheet, hot-rolled steel sheet longitudinal two positions of a total of four locations two places in the hot-rolled steel sheet width direction across the hot-rolled steel sheet, respectively a cooling header, from cooling nozzles attached to respective cooling headers injecting cooling water toward the center of the four locations have been proposed.
[0007]
　Patent Document 4, in a cooling device, a draining nozzle between a plurality of cooling banks provided for cooling was injected coolant from a plurality of cooling banks in the hot-rolled steel sent from the finishing mill, the draining use nozzles are arranged laterally on both sides in the width direction of the hot-rolled steel, it has been proposed for ejecting high-pressure water along the width direction of the hot rolled steel.
[0008]
　Patent Document 5, in a cooling device for cooling a hot-rolled material traveling on the hot run table by curtain of cooling water to drop from the slit nozzle of the cooling water header, a spray disposed on both sides of the hot run table from each spray and the pressure water jetted it has been proposed to orient across the outer end than the central portion in the width direction of the hot-rolled. Then, the pressure water from the spray, and removing the coolant mutual interference flow generated on the hot rolled material.
[0009]
　Patent Document 6, when cooling the front and rear hot-rolled steel sheet finishing rolling, the draining method for draining the cooling water injected against the hot-rolled steel sheet, one side of the width direction of the hot rolled steel sheet or more draining nozzles arranged side by side in the conveying direction of the hot-rolled steel sheet in both, the draining of the cooling water is carried out has been proposed by ejecting draining water in the width direction of the hot-rolled steel sheet.
CITATION
Patent Document
[0010]
Patent Document 1: JP 2008-110353 Patent Publication
Patent Document 2: International Publication WO2011 / one hundred fifteen thousand two hundred and seventy-seven No.
Patent Document 3: JP 2015-073995 Patent Publication
Patent Document 4: JP-B 59-013573 Patent Publication
Patent Document 5: JitsuHiraku Akira 57-106752 JP
Patent Document 6: International Publication WO2016 / 006402 JP
Summary of the Invention
Problems that the Invention is to Solve
[0011]
　In the disclosed cooling method in Patent Document 1, at least the strip upper surface in a second cooling step to cool in laminar cooling or jet cooling, but the hot rolled strip is cooled at a nucleate boiling, such laminar cooling or in the jet cooling, it is not possible to carry out the draining of cooling water. Then, when performing draining example by rod-shaped high pressure fluid from the injection nozzle, and water leakage from the high pressure fluid gap, can not be performed completely draining the said high pressure fluid, it occurs cooled by the plate clean water on the steel strip . As a result, cooling of the hot rolled strip becomes uneven. Also, when performing draining example rolls, are difficult biting early if the strip tip is jumped, initially requires facilities such as a roll is retracted, it is economically disadvantageous. Further, the line speed expected by hot rolling (for example, about 15 m / sec), when the steel strip passing plate, intermittent contact of the roll due to flapping of the hot rolled strip, hot rolled strip is due to vibration there is a fear that suffer the damage.
[0012]
　In this respect, instead of injecting the cooling water from above the hot rolled steel sheet, the disclosed apparatus and methods in Patent Documents 2 to 6, the cooling water toward the side of the hot-rolled steel sheet in the width direction (draining water) It is injection.
[0013]
　In the delivery side of the rolling mill water spraying device disclosed in Patent Document 2, although with water spray in the width direction of the steel plate from the cooling nozzle, the collision area in the steel plate of the sprayed water from the cooling nozzle, almost covered the entire region in the width direction of the steel plate. Therefore, two impact area from a pair of the cooling nozzles disposed on both sides of the outer conveyor line overlaps at the ends of the steel plate. Here, in the region of impact of the cooling nozzle, the proximal end portion of the cooling nozzle side becomes high because the distance from the cooling nozzle is near. Then, since the overlap at both ends of the two impact area is steel plate from a pair of the cooling nozzle, the end portion becomes supercooled, the cooling unevenness in the width direction. Further, in the invention disclosed in Patent Document 2, in order to suppress the scale of the steel sheet surface, the steel sheet surface is intended to be covered by water, water is small, the ability to discharge the plate clean water on steel Low. Therefore, the steel plate cooling becomes uneven.
[0014]
　In disclosed in Patent Document 3 cooling device has a cooling nozzle provided at four positions in the hot-rolled steel sheet width direction by jetting cooling water toward the center of the four locations, in such a case, the width direction in the vicinity of the collision point of the cooling water from the pair of cooling nozzles facing the low ability to discharge the plate clean water on the hot-rolled steel sheet, also the plate clean water retained even at the center. This plate clean water, cooling the hot rolled steel sheet becomes nonuniform.
[0015]
　In disclosed in Patent Document 4 cooling device, draining nozzle is ejecting high pressure water along the width direction of the hot-rolled steel, collisions with hot-rolled steel high-pressure water jetted from draining nozzle region is almost covered the entire region in the width direction of the hot rolled steel. Therefore, two impact area from a pair of draining nozzle which is disposed laterally on both sides of the hot-rolled steel, also overlap in both end portions of the hot-rolled steel sheet. Since the proximal end portion of the draining nozzle side in the collision region from draining nozzle as described above tends to be a result supercooling the high pressure, both ends of the hot-rolled steel sheet which overlaps two impact area from the nozzle for a pair of draining part becomes supercooled, the cooling unevenness in the width direction. Incidentally, Patent Document 4 does not disclose providing a plurality of pairs of nozzles for a pair of draining.
[0016]
　In disclosed in Patent Document 5 cooling device, the pressure water is directed across the outer end than the central portion in the width direction of the hot-rolled, hot rolled pressure water injected from the spray ejected from the spray collision area in the wood covers over at least half the width of the hot-rolled. Therefore, two impact area from a pair of spray disposed laterally on both sides of the hot rolled material overlap at the center of the hot-rolled. Then, when using the spray to cool the hot-rolled, the central portion of the hot-rolled overlapping two impact area from a pair of the spray becomes supercooled, the cooling unevenness in the width direction. Incidentally, Patent Document 5 does not disclose providing a plurality of pairs of a pair of spray.
[0017]
　In the disclosed draining method in Patent Document 6, draining nozzle injects draining water in the width direction of the hot-rolled steel sheet. Then, the collision area of ​​the draining water injected from a plurality of draining nozzles covers the entire region in the width direction of the hot-rolled steel sheet, further impact area from the draining nozzle portion in the width direction in the impact region adjacent to each other in the width direction It is arranged to overlap. Then, when using the draining nozzle to cool the hot-rolled steel sheet, since the overlap region of collision of the draining nozzle, the overlapped portion becomes supercooled, the cooling unevenness in the width direction.
[0018]
　As described above, the cooling method and cooling apparatus of the conventional hot rolled steel sheet, there is room for improvement.
[0019]
　The present invention has been made in view of the foregoing, and an object thereof is to appropriately and uniformly cool the hot-rolled steel sheet after finish rolling of a continuous hot rolling process.
Means for Solving the Problems
[0020]
　To achieve the above object, the present invention provides a method of cooling a hot-rolled steel sheet after finish rolling of a continuous hot rolling process, the hot-rolled steel sheet to a region of the steel plate conveyance area occupied on the conveyor rolls when a pair of spray nozzles are arranged on both sides of the width direction side of the steel plate conveyance region, and, the spray nozzle pairs are pairs arranged in the conveying direction of the hot-rolled steel sheet, with respect to the steel plate conveyance region, said spray by injecting cooling water in the widthwise direction of the steel sheet transfer region from the nozzle, the hot-rolled steel sheet is cooled, the collision area of ​​the steel plate conveyance area of ​​the cooling water sprayed from the spray nozzle, the distal end portion of the injection direction steel located on the end of the transport region, positioned inside the proximal end steel plate conveyance region, in said spray nozzle pairs, proximal ends of the two said impingement region formed an association unit to match the width direction It is characterized in that The width of the steel sheet transport area, the cooling method of the present invention is the same as the maximum width of the hot rolled steel sheet cooling schedule. Therefore, when cooling the hot-rolled steel sheet having a width narrower than the maximum width, the cooling water hot rolled steel sheet of the narrow width is injected into the portion not occupied by the width direction end portion side of the steel plate conveyance region, the hot rolled steel sheet without colliding directly falls to the lower pass line of hot-rolled steel sheet.
[0021]
　According to the present invention, since the meeting part is formed in two impingement region of the spray nozzle pairs, these collision regions without overlap in the width direction of the steel sheet conveyance area, yet cover the entire width. Therefore, it is possible to impact area as in the prior art to suppress the uneven cooling due to overlap in the width direction, it is possible to uniformly cool the width direction of the hot-rolled steel sheet. In other words, to form the association of the impact area as in the present invention, in the conventional documents mentioned above are those novel not disclosed at all, which is very useful for uniform cooling of the hot rolled steel sheet.
[0022]
　The association unit, located within the associated zone is divided into the center in the width direction of the steel plate conveyance region, the width of the associated zone satisfies the following formula (1), the association portion of said spray nozzles adjacent pair in the transport direction widthwise spacing may be greater than or equal to the length of the conveying direction of the impact region.
W ≦ (D + 2d) - (D + d) sin [theta 2 / sin (theta 1 + theta 2 ) · · · (1)
where,
W: the width of the associated zone
D: the width of the steel sheet conveyance area
d: injection port of the spray nozzle and its front horizontal distance between the end portion of the steel plate conveyance region of
theta 1 : spraying angle
theta 2 : forming a spray installation angle (from the injection port of the perpendicular line and the spray nozzle of the injection port of the spray nozzle of the line connecting the widthwise center of the steel plate conveyance region corner)
[0023]
　The cooling zone in which a plurality toward a pair of spray nozzle pairs of the steel sheet conveyance region cooling water is injected is divided into a plurality of cooling sub-zone in the conveying direction, wherein the cooling small zone N pairs (N is an integer) spray nozzle pair is disposed, the associated zone is divided into said N associative small zone at equal intervals in the width direction, the cooling in the meeting small zone in a small zone, is arranged one of said associated portions respectively the meeting portion of the cooling sub-zone, toward the downstream side from the upstream side in the transport direction, are disposed towards the meeting the association small zone of the other end from the small zone of one end of the meeting zone it may be.
[0024]
　The cooling small zone, k pieces in the conveying direction (k is a divisor of N) is divided into a divided cooling small zone, and in the divided cooling small zone of the i-th in the conveying direction (i is an integer from 1 to k) the association unit, the direction from the first one end portion side of the associated zone N th other end side, jk + i th from the i-th (j is from 1 to (N / k-1) it may be arranged to integers).
[0025]
　Cooling the hot rolled steel sheet by the cooling water from the spray nozzle may be performed by nucleate boiling region.
[0026]
　The present invention according to another aspect is an apparatus for cooling a hot-rolled steel sheet after finish rolling of a continuous hot rolling process, when the hot-rolled steel sheet and the steel sheet transporting region an area occupied on the conveyor rolls, the steel plate with respect to the transport area, the spray nozzles for injecting cooling water to the width direction of the steel sheet conveyance regions are arranged in a pair on both sides in the width direction side of the steel plate conveyance region, and, conveying the spray nozzle pairs of the hot-rolled steel sheet a plurality of pairs arranged in a direction, the spray nozzle is in the impact region in the steel plate conveyance area of ​​the cooling water sprayed from the spray nozzle, the distal end portion of the injection direction is located at the end of the steel plate conveyance region, near Katatan portion is arranged to be positioned inside of the steel plate conveyance region, said spray nozzle pairs, proximal end portions of the two said impact region are arranged to form an association unit to match the width direction and wherein the There.
[0027]
　The association unit, located within the associated zone is divided into the center in the width direction of the steel plate conveyance region, the width of the associated zone satisfies the following formula (1), the said spray nozzle pairs adjacent to the conveying direction, respectively the width direction of the spacing of the meeting portions may be arranged such that the conveying direction over the length of the collision area.
W ≦ (D + 2d) - (D + d) sin [theta 2 / sin (theta 1 + theta 2 ) · · · (1)
where,
W: the width of the associated zone
D: the width of the steel sheet conveyance area
d: injection port of the spray nozzle and its front horizontal distance between the end portion of the steel plate conveyance region of
theta 1 : spraying angle
theta 2 : forming a spray installation angle (from the injection port of the perpendicular line and the spray nozzle of the injection port of the spray nozzle of the line connecting the widthwise center of the steel plate conveyance region corner)
[0028]
　The cooling zone in which a plurality toward a pair of spray nozzle pairs of the steel sheet conveyance region cooling water is injected is divided into a plurality of cooling sub-zone in the conveying direction, wherein the cooling small zone N pairs (N is an integer) spray nozzle pair is disposed, the associated zone is divided into said N associative small zone at equal intervals in the width direction, the cooling in the meeting small zone in a small zone, is arranged one of said associated portions respectively the meeting portion of the cooling sub-zone, toward the downstream side from the upstream side in the transport direction, are disposed towards the meeting the association small zone of the other end from the small zone of one end of the meeting zone it may be.
[0029]
　The cooling small zone, k pieces in the conveying direction (k is a divisor of N) is divided into a divided cooling small zone, and in the divided cooling small zone of the i-th in the conveying direction (i is an integer from 1 to k) the association unit, the direction from the first one end portion side of the associated zone N th other end side, jk + i th from the i-th (j is from 1 to (N / k-1) it may be arranged to integers).
Effect of the invention
[0030]
　According to the present invention, it is possible to appropriately and uniformly cool the hot-rolled steel sheet after finish rolling of a continuous hot rolling process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031]
FIG. 1 is an explanatory view schematically showing a configuration of a continuous hot rolling equipment provided with a cooling device according to the present embodiment.
Is a side view showing a schematic configuration of [2] cooling device according to the present embodiment.
3 is a plan view schematically showing the configuration of a cooling device according to the present embodiment.
FIG. 4 is an explanatory diagram showing a collision area in the hot-rolled steel sheet of the cooling water sprayed from the spray nozzle side sprayer.
FIG. 5 is an explanatory view seen from the conveying direction front showing a pair of the arrangement of the spray nozzles.
Is an explanatory view showing the dimensions required to calculate the FIG. 6 the width of the associated zone.
7 is an explanatory view showing a correlation widthwise temperature difference ΔT1 of Lf / Ln and the hot-rolled steel sheet.
8 is an explanatory view showing a correlation of the upper surface temperature difference ΔT2 of separation and hot-rolled steel from the meeting portion.
9 is an explanatory diagram showing an example of the arrangement of the meeting portion.
Is an explanatory diagram showing an example of the arrangement of FIG. 10 meeting portion.
11 is a plan view schematically showing the configuration of a cooling device in the other embodiments.
[Figure 12] is an explanatory view of an embodiment, (a) shows the case where the association portion is formed in the region of impact of the spray nozzle pair shows (Example 1), (b) the collision from the spray nozzle pairs If the regions overlap indicates (Comparative example 1), and (c) shows the case where no overlap collision region from the spray nozzle pairs (Comparative example 2).
DESCRIPTION OF THE INVENTION
[0032]

　The following describes embodiments of the present invention. Figure 1 is an explanatory diagram showing an outline of a hot rolling mill 1 of the arrangement having a cooling device according to the present embodiment.
[0033]
　In continuous hot rolling equipment 1, a slab 5 which heated continuously rolled across the upper and lower roll, hot-rolled steel sheets 10a (hereinafter be thinned to the thickness of the minimum 1 mm, the sign of the in the drawings as described below 10 is intended to refer to any of the steel plate conveyance region 10 or the hot-rolled steel sheet 10a.) the winds. Continuous hot rolling mill 1 includes a heating furnace 11 for heating the slab 5, the width direction rolling mill 12 for rolling the slab 5 heated in the heating furnace 11 in the width direction, which is rolled in the width direction by rolling the slab 5 from the vertical direction and the roughing mill 13 to a coarse bar, the finish rolling mill 14 the crude bar further continuously to a predetermined thickness to a hot finish rolling, hot this finishing mill 14 a cooling device 15 for the finish rolled hot-rolled steel sheet 10a is cooled by cooling water, a hot-rolled steel sheet 10a, which is cooled by the cooling device 15 and a winding device 16 for winding into a coil. The above is not limited to this a general configuration.
[0034]
　In the heating furnace 11, the process of heating the slab 5 which has been carried in from outside through the spout to a predetermined temperature is performed. When the heating treatment in the heating furnace 11 is completed, the slab 5 is conveyed into the heating furnace 11 outside, the process proceeds to rolling process by rough rolling mill 13.
[0035]
　Slab 5 which has been conveyed is rolled to a thickness of 30 ~ 60 mm about crude bar by the rough rolling mill 13 is conveyed to the finish rolling mill 14.
[0036]
　In finishing mill 14, rolling coarse bar that has been transported to the hot-rolled steel sheet 10a of the plate thickness of about several mm. Rolled hot rolled steel sheet 10a is fed to the cooling device 15 is transported by the transport roll 17. Hot-rolled steel sheet 10a is cooled by the cooling device 15 and is coiled by the take-up device 16.
[0037]

　Next, the details of the cooling device 15 according to this embodiment. Figure 2 is a side of the cooling device 15 schematically illustrated, Figure 3 shows a plan of the cooling device 15 schematically. As shown in FIG. 2, the upper cooling device 20 disposed above the hot-rolled steel sheet 10a to be conveyed on the conveying rolls 17 of the run-out table, the lower cooling device disposed below the said hot-rolled steel sheet 10a ( It has not shown) and.
[0038]
　Upper cooling device 20 has a plurality of cooling water nozzle 21 for injecting cooling water vertically downwardly from above the hot-rolled steel sheet 10a to the upper surface of the hot-rolled steel sheet 10a. The cooling water nozzle 21, for example, slit laminar nozzle or pipe laminar nozzles are used. The cooling water nozzles 21 are arranged side by side a plurality along the conveying direction of the hot-rolled steel sheet 10a (thick arrow direction in the drawing). Incidentally, the cooling water nozzle 21 may be other nozzle is not limited to these nozzles.
[0039]
　The downstream side of the upper cooling device 20, water draining device 30 for draining the plate clean water 22 cooling water injected from the upper cooling device 20 is flowing is entrained steel is provided. Dewatering device 30 of this embodiment, as shown in FIG. 3, the spray device 31 for a plurality of draining is used, the conveyance direction upstream fluid for draining from the spray device 31, for example, so as to inject the water.
[0040]
　At the conveying direction downstream side of the draining device 30, the side spray device 40 is provided. In this embodiment, the spray nozzle 41, both sides in the width direction side of the steel plate conveyance region 10 (existing area of ​​hot-rolled steel sheet 10a that is conveyed on the pass line), and a plurality placed along the conveying direction . For convenience of illustration, FIG. 3, but a total of 10 pieces of the spray nozzles 41 of each five side is shown, of course not limited to this, the number of installation can be appropriately selected as necessary.
[0041]
　Here, the steel plate conveyance region 10, hot-rolled steel sheet 10a is a region occupied on the conveyor rolls 17. That is, the steel plate conveyance region 10, the transport region in the case of a line that connects the vertices of the transport roll 17 in a side view, the width dimension is producible maximum dimension of hot-rolled steel sheet 10a in a plan view (maximum width) it is. In the following, the width of the width and the hot-rolled steel sheet 10a of the steel plate conveyance area 10 is described as a match, the reference numeral 10 in the figure in response to the scene to be applied, the steel plate conveyance region 10 or the hot-rolled steel sheet 10a It is intended to refer to either. Since the width of the steel sheet transport region 10 as described above is the maximum width of the hot-rolled steel sheet 10a, the side spraying device 40, to cool the hot-rolled steel sheet 10a having a width narrower than the maximum width, the the difference steel widthwise end portion side cooling water injected to the portion of the transfer region 10, without colliding to the hot-rolled steel sheet 10a, as it falls to the bottom of the pass line of hot-rolled steel sheet 10a.
[0042]
　The downstream side of the side spraying device 40, draining device 50 is provided. Dewatering device 50 of this embodiment, a spray device 51 for a plurality of draining is used, the conveyance direction upstream, so as to inject a fluid, such as water for draining from the spray device 51 there.
[0043]
　In plan view, between the draining unit 30 and the side spraying device 40, the temperature sensor MT is arranged to measure the temperature of the hot-rolled steel sheet 10a, also between the draining device 50 and the winding device 16, heat temperature sensor CT for measuring the temperature of the rolled steel sheet 10a is disposed. Temperature signal from the temperature sensor MT is for example used to control the upper cooling device 20 (e.g., feedback control), the temperature signal from the temperature sensor CT is used for example to control the side spraying device 40 (e.g., feedback control) .
[0044]
　Cooling device 15 according to this embodiment has the structure described above, the finishing mill 14 at a predetermined plate hot rolled steel sheet 10a that is rolled to a thickness, first the upper cooling device 20 from the cooling water nozzles 21 is cooled by cooling water (shown in the lower cooling device as described above is omitted). And then draining is performed by draining device 30. Hot-rolled steel sheet 10a, which is drained and then is further cooled by the side spraying device 40.
[0045]
　In this embodiment, it cooled to about 200 ° C. The hot-rolled steel sheet 10a in the cooling device 15. In this way it is possible to hot-rolled steel sheet 10a to about 200 ° C. wound properly and uniformly cooled, for example, in the hot-rolled steel sheet 10a that is adjusted to a predetermined component, martensite tempered during cooling after winding and the like to produce, can be advantageously produced hot-rolled steel sheet 10a of deformability is improved. In this case, there coiling temperature martensitic transformation starting temperature (Ms point) or less, by the water boiling point greater than the effect that can prevent the red scale is formed on the hot-rolled steel sheet 10a.
[0046]

　Next, the details of the side spraying device 40 described above. In the side spray device 40, as shown in FIG. 4, a pair of spray nozzles 41, 41 are arranged in the width direction side of the steel plate conveyance area 10. Also, the spray nozzle pairs 42 consisting of the pair of spray nozzles 41, 41 are a plurality of pairs arranged in the conveying direction of the hot rolled steel sheet 10a. Incidentally, the spray nozzles 41 as described above, the number of installation of spray nozzle pairs 42 can be appropriately selected as necessary.
[0047]
　Spray nozzles 41 can, as shown in FIG. 5, the oblique direction from above the steel plate conveyance region 10, and to inject cooling water in the widthwise direction of the steel plate conveyance area 10. Further, as shown in FIG. 4, the collision area 43 in the steel plate conveyance area 10 of the cooling water sprayed from the spray nozzle 41, the injection direction of the distal end portion 43a (an end portion of the spray nozzle 41 opposite) steel plate conveyance on the edge portion of the region 10, the proximal end portion 43 b (the end of the spray nozzle 41 side) is located inside of the steel plate conveyance area 10. In the spray nozzle pair 42, the proximal end portion 43b of the two impact area 43, 43, 43b to form an association unit P coincides with the width direction (thick line portion in FIG. 4). Here, the proximal end portion 43b of the two impact region 43, and the match 43b is the width direction, as shown in FIGS. 4 and 5, the one width side of the steel plate conveyance region 10 collision region 43 of the and the proximal end portion 43b, and a proximal end portion 43b of the impact region 43 of the other width side, as viewed in the field of view of FIG. 5, the matched without overlapping or spaced apart at the meeting portion P, in the steel plate conveyance region 10 It means that a collision region 43 in the width direction is visible in one of the impact area continuous from one end of the steel plate conveyance area 10 to the other end.
[0048]
　In such a case, the spray nozzle 41 with respect to the steel plate conveyance region 10, with a predetermined injection angle, since it is arranged to inject from above obliquely, if the upper surface of the hot-rolled steel sheet 10a is a plate clean water 22 remaining also it is, which while discharging an end side of the hot-rolled steel sheet 10a to the (distal end side), it is possible to cool the hot rolled steel sheet 10a.
[0049]
　Further, since the association portion P of the collision area 43 is formed in a spray nozzle pair 42, these impact region 43 and 43, without overlapping in the width direction of the steel plate conveyance region 10, moreover covers the entire width . Therefore, it is possible to impact area as in the prior art to suppress the uneven cooling due to overlap in the width direction, it is possible to uniformly cool the width direction of the hot rolled steel sheet 10a.
[0050]

　the association portion P is, proximal end portions 43b of the two impact area 43 is a portion 43b are in contact with each other, as opposed to the central portion in a single collision region 43, industrially are , etc. it allowed forced to the position of the proximal end portion 43b varies to some extent, the association unit P is industrially including instability in cooling effect. Therefore, as an extreme case, assuming that all of the meeting part P of the spray nozzle pairs 42 are aligned in the widthwise central portion of the steel plate conveyance region 10, it is expected that the plate in the variation of the cooling stop temperature is increased . In contrast, the present inventors have studied intensively and found that it is preferable to disperse all the meeting part P of the spray nozzle pairs 42 within a predetermined range.
[0051]
　Specifically, the association unit P as shown in FIG. 4, is located within the associated zone E which is defined in the center in the width direction of the steel plate conveyance area 10. Width W of the meeting zone E satisfies the following formula (1).
W ≦ (D + 2d) - (D + d) sin [theta 2 / sin (theta 1 + theta 2 ) · · · (1)
where,
W: the width in the width direction of the steel plate conveyance area 10 of the associated zone E
D: the width of the steel plate conveyance region 10
d: horizontal distance of the injection port 41a of the spray nozzle 41 and the end portion of the steel plate conveyance area 10 of the front
theta 1 : (vertical direction of the injection angle of the cooling water sprayed from the spray nozzle 41) spraying angle
theta 2 : spray installation angle (angle formed by a line connecting the widthwise center of the steel plate conveyance area 10 from the injection port 41a of the perpendicular line and the spray nozzle 41 of the injection port 41a of the spray nozzle 41)
[0052]
　In deriving the width W of the meeting zone E, the present inventors have focused on reaching the distance to the steel plate conveyance area 10 of the cooling water sprayed from the spray nozzle 41. As shown in FIG. 6, a far distance from the injection port 41a of the spray nozzle 41 to the distal end portion 43a of the collision area 43 and Lf, from the injection port 41a of the spray nozzle 41 to the proximal end portion 43b of the collision area 43 at a near distance and Ln. Incidentally, FIG. 6 illustrates the case where the association unit P is located at the end of the meeting zone E.
[0053]
　Width W of the meeting zone E is derived to meet the Lf / Ln ≦ 2. Hereinafter, a description will be given of grounds for Lf / Ln ≦ 2. The present inventors have conducted a simulation of the cooling of the hot rolled steel sheet 10a with side spray device 40, and found a tendency shown in Fig. Figure 7 shows the Lf / Ln widthwise temperature difference of the upper surface of the hot-rolled steel sheets 10a, varying (horizontal axis) Delta] T1 (vertical axis). Widthwise temperature difference ΔT1, after hot-rolled steel sheet 10a is heated and cooled condensate in (e.g. just before being wound by the winding device 16), the difference between the maximum temperature and the minimum temperature in the width direction of the hot-rolled steel sheet 10a is there.
[0054]
　Referring to FIG. 7, if the Lf / Ln> 2, widthwise temperature difference ΔT1 of hot-rolled steel sheet 10a increases. This is because when Lf / Ln is larger, the difference in force when the cooling water collides with the distal end portion 43a and the proximal end portion 43b is increased, because the difference between the cooling capacity is increased. In contrast, if the Lf / Ln ≦ 2, by cooling water after colliding to the near side flows distally, the cooling of the far side is performed, the width direction temperature difference hot-rolled steel sheet 10a ΔT1 is small, the small variations in the cooling capacity in the width direction of the hot rolled steel sheet 10a. Therefore, to uniformly cool the hot-rolled steel sheet 10a in the width direction, Lf / Ln ≦ 2 is preferred.
[0055]
　The far range Lf and near distance Ln from the geometric relationship shown in FIG. 6, respectively, the following equation (2) is expressed by (3).
Lf = (D + d) / cos {90 ° - (theta 1 + theta 2 )}
· · · (2) Ln = (D / 2 + d-W / 2) / cos (90 ° - [theta] 2 ) · · · (3)
[0056]
　The formula (2), put the Lf / Ln ≦ 2 (3), and rearranging the width W of the meeting zone E, the above-mentioned formula (1) is derived.
≦ W (D + 2d) - (D + d) sin [theta 2 / sin (theta 1 + theta 2 ) · · · (1)
[0057]
　Incidentally, for example, the width D of the steel plate conveyance region 10 is 2000 mm, the horizontal distance d between the end of the spray nozzle 41 and the steel sheet transfer region 10 is 250 mm, spraying angle theta 1 is is 20 °, the spray installation angle theta 2 in the case is 60 °, the Lf / Ln = 2, the width W of the meeting zone E is 500 mm. Further, for example, the width D of the steel plate conveyance region 10 is 2000 mm, the horizontal distance d between the end of the spray nozzle 41 and the steel sheet transfer region 10 is 250 mm, spraying angle theta 1 is is 20 °, the spray installation angle theta 2 in the case is 45 °, the Lf / Ln = 2, the width W of the meeting zone E is 785 mm.
[0058]
　Moreover, (the height h up to the injection port 41a of the steel plate conveyance region 10 spray nozzle 41 from the) installation height h of the spray nozzle 41 is about 400 ~ 600 mm is practical. When installation height is higher than 600 mm, the cooling capacity is lower at the distal end portion 43a. On the other hand, if the installation height is less than 400 mm, to ensure the collision area 43, spraying angle theta 1 it is necessary to reduce the, in this case, it becomes difficult to produce a spray nozzle 41.
[0059]

　meeting part P as described above, the proximal end portion 43b of the two impact area 43 is a portion 43b are in contact with each other, for industrial unstable elements in the cooling effect because they contain, the present inventors have studied intensively, association portion P of the spray nozzle pairs 42, 42 adjacent in the conveying direction, P was found to be preferable to separate more than a predetermined distance.
[0060]
　Specifically, the interval Q of meeting part P, the width direction of P of the spray nozzle pairs 42, 42 adjacent in the conveying direction as shown in FIG. 4, the transport direction of the length R more impact area 43.
[0061]
　The present inventors have found that in the simulation of the cooling of hot rolled steel sheet 10a with side spray device 40, occurs at the meeting portion P including the instability in industrial cooling effect, the temperature of the meeting part P to surrounding temperature assuming the difference, the temperature difference is found a tendency that shown in FIG. 8 for the extent of influence on the surroundings. Figure 8 shows the relationship between the distance in the steel plate width direction from the meeting part P upper surface temperature difference (horizontal axis) and hot-rolled steel sheet 10a Delta] T2 (vertical axis). In the figure, the distance from the meeting part P, industrial instability affects (top temperature difference ΔT2 increases) in a range in the conveying direction of the length R of the collision area 43 as described later that and that the length R as a reference from a distance from the meeting part P, a multiple n for the length R (n is an integer) indicates a. The upper surface temperature difference ΔT2 of hot-rolled steel sheet 10a includes a top surface temperature of the hot-rolled steel sheet 10a in association portion P, the hot rolled steel sheet in spaced apart measurement points (multiple n to the length R) distance from the association unit P 10a is the difference between the upper temperature.
[0062]
　Referring to FIG. 8, when n is smaller than 1, that is, when the measuring point is close to the meeting part P, the top surface temperature difference ΔT2 is larger. In contrast, when n is 1 or more, that measurement point when away from the meeting part P, the top surface temperature difference ΔT2 becomes smaller almost zero.
[0063]
　In this case, the association portion P of the spray nozzle pairs 42, 42 adjacent to the conveying direction, the distance Q in the width direction of the P, when n is smaller than 1, i.e. in the conveying direction of the spacing Q collision region 43 than the length R small case, a large upper surface temperature difference ΔT2 for larger upper surface temperature difference ΔT2 and the other meeting part P for one meeting portion P is superposed in the conveying direction. Then, it is impossible to uniformly cool the hot-rolled steel sheet 10a in the width direction. In contrast, n is not less than 1, when the distance Q is the length R above, since the upper surface temperature difference ΔT2 is small, it is possible to suppress the widthwise uneven cooling of hot rolled steel sheet 10a. Therefore, the interval Q in the width direction of the meeting part P is preferably not less conveying direction length R more impact area 43.
[0064]
　Incidentally, for example, the width D of the steel plate conveyance region 10 is 2000 mm, the horizontal distance d between the end of the spray nozzle 41 and the steel sheet transfer region 10 is 250 mm, the horizontal spray angle of the cooling water sprayed from the spray nozzles 41 theta 3 when it is 3 °, the length R of the conveying direction of the impact region 43 becomes 65mm (= 1250mm × tan (3 ° / 2) × 2).
[0065]

　in association zone E as shown in FIG. 9, the association unit P is arranged in a staggered manner.
[0066]
　Meeting zone E is, N pieces at regular intervals in the width direction, in this embodiment is divided eight meeting the small zone e (association small zone e1 ~ e8). Incidentally, N represents a integer of 2 or more, can be arbitrarily selected.
[0067]
　Further, in the side spraying device 40, when the region where cooling water is jetted from all of the spray nozzle pairs 42 in the steel plate conveyance region 10 and cooling zone F, the cooling zone F, a plurality of cooling sub-zone in the conveying direction It is divided into f. Each cooling small zone f, spray nozzle pairs 42 N pairs equal in number to the association small zone e is arranged. For convenience of illustration, FIG. 9, the cooling small zone f1 ~ f3 are shown, the number of cooling small zone f, of course not limited thereto, can be appropriately select the number as necessary, side spray It is determined according to the number of spray nozzle pairs 42 in the device 40. For example, when a spray nozzle pair 42 which is M × N pairs (M is an integer of 2 or more), cooling small zone f are provided M pieces.
[0068]
　In one cooling small zone f, the one associated small zone e are arranged one meeting part P. Also, in one of the cooling sub-zone f, association portion P is directed to the downstream side from the upstream side in the transport direction, meeting small zone of the other end from the meeting small zone e1 of one end of the meeting zone E e8 It is located toward the.
[0069]
　Here, association portion P of the spray nozzle pairs 42, 42 that are adjacent in the transport direction, if P is located in the same association small zone e, may become supercooled by the association unit P, P overlap. In this regard, in the present embodiment, since the association portion P are arranged in a zigzag pattern in one of the cooling sub-zone f, it is possible to disperse the meeting part P in the width direction, the minimum of the portion to be supercooled it can be of. Therefore, it is possible to uniformly cool the width direction of the hot rolled steel sheet 10a.
[0070]
　Further, as shown in FIG. 10, one of the cooling sub-zone f1 (f2, f3) further k pieces in the conveying direction, two divided cooling small zone in this embodiment f11, f12 (f21, f22, f31, f32) it may be divided into. Incidentally, k is a divisor of N, it can be arbitrarily selected.
[0071]
　In cooling small zone f1, the first divided cooling small zone f11 in the conveying direction, the association unit P is arranged in association small zone e1, e3, e5, e7. Also, the second divided cooling small zone f12 in the conveying direction, the association unit P is associated small zone e2, e4, e6, e8 are arranged. When such cooling small zone f1 is divided into two in the transport direction, in the cooling small zone f1, 1 single meeting part P is arranged for each two associated small zone e in the width direction. Also in the cooling small zone f2, f3, association portion P are arranged in the same manner.
[0072]
　Generalizing the arrangement of the meeting part P, the split cooling small zone f of i-th in the conveying direction (i is an integer from 1 to k), the association unit P is, one end side of the associated zone E 1 toward the N-th other end side from the second, jk + i th from the i-th (j is an integer from to 1 (N / k-1)) would be located in.
[0073]
　The number k of one of the cooling sub-zone f is divided is not limited to two, and may be a divisor of N. In the above example, N is the order is 8, the number k of cooling small zone f is divided may be four.
[0074]
　Sites Thus in the example shown in FIG. 10, it is possible to receive the same effect as the arrangement of the meeting part P shown in FIG. 4, i.e., to be supercooled by dispersing the association unit P in the width direction it can be minimized. Moreover, if one of the cooling sub-zone f is divided into a plurality, it is possible to further disperse the association unit P in the width direction. Therefore, it is possible to uniformly cool the width direction of the hot rolled steel sheet 10a.
[0075]
　The arrangement of the meeting part P is not limited to the staggered, it may be any arrangement to distribute the associated portion P in the width direction may be, for example arranged such sine curve shape.
[0076]

　in the side spraying device 40, the cooling of the hot rolled steel sheet 10a by the cooling water from the spray nozzle 41 is carried out in the nuclear boiling region.
[0077]
　Here, in the cooling of the hot rolled steel sheet 10a, in accordance with the upper surface temperature of the hot-rolled steel sheet 10a, boiling state of the coolant on the hot-rolled steel sheet 10a varies. Specifically, varying from a high temperature side of the upper surface temperature film boiling region, the transition boiling region, in the order of the nucleate boiling region.
[0078]
　The film boiling region, when injecting cooling water on the upper surface of the hot-rolled steel sheet 10a, the cooling water evaporates immediately after the previous, or reaches to reach the hot-rolled steel sheet 10a, the upper surface of the hot-rolled steel sheet 10a is covered in vapor film the break state. In this cooling, the vapor film on the upper surface of the hot-rolled steel sheet 10a inhibits the transmission of heat, the heat transfer coefficient of the hot-rolled steel sheet 10a is low, the cooling capacity is low.
[0079]
　The transition boiling region, when injecting cooling water on the upper surface of the hot-rolled steel sheet 10a, the location of contact cooling water with the vapor film becomes mixed in the upper surface of the hot-rolled steel sheet 10a. In this transition boiling region, the heat transfer coefficient increases with a decrease of the upper surface temperature of the hot-rolled steel sheet 10a. Therefore, the upper surface temperature is high place is hard cold hot-rolled steel sheets 10a, where the upper surface temperature is low rapidly cooled, local variations occur in the upper surface temperature of the hot-rolled steel sheet 10a. Then, it is impossible to uniformly cool the hot-rolled steel sheet 10a.
[0080]
　In nucleate boiling region, when injecting cooling water on the upper surface of the hot-rolled steel sheet 10a, not generated vapor film on the upper surface of the hot-rolled steel sheet 10a, the cooling water directly contacts the upper surface of the hot-rolled steel sheet 10a. Therefore, in the nucleate boiling region, the high heat transfer coefficient of the hot-rolled steel sheets 10a, the cooling capacity is high.
[0081]
　In this embodiment, the cooling of hot-rolled steel sheet 10a in the side spraying device 40 so performed in the nucleate boiling region, it is possible to uniformly cool the hot-rolled steel sheet 10a with a high cooling capacity. In other words, in the side spray device 40 can the temperature of the hot-rolled steel sheet 10a to finely control, it is possible to cool to 200 ° C. of about the target temperature.
[0082]
　Here, in this way concrete conditions for cooling by nucleate boiling region will be described. In the present embodiment, which aims to cool the side spray device 40 to a low temperature of about 200 ° C. As described above, in order to achieve this, one spray nozzle 41 is large water density of, for example, 4m 3 / m 2 by spraying cooling water of water density of / min, cooling the hot rolled steel sheet 10a.
[0083]
　For example, "Forced cooling of steel" 1978 November 10, the Japan Iron and Steel Association, the correlation of the steel surface temperature and the heat transfer coefficient is disclosed in each water density. In addition, for example, "cooling technology of high temperature steel" Mitsuzuka Masashi Author iron and steel Vol. 79 (1993) in Japan Iron and Steel Institute, the correlation of the steel surface temperature and the heat transfer coefficient is disclosed in each water density. Water flow rate 4m described above 3 / m 2 when ensuring / min, from these correlations, nucleate boiling cooling, the upper surface temperature of the hot-rolled steel sheet 10a becomes less cooling 400 ° C..
[0084]
　Further, as described above, a 2000mm example, the width D of the steel plate conveyance region 10, when the length R of the conveying direction of the impact region 43 is 65 mm, the proximal end portion 43b is steel transfer area of the collision area 43 If 10 is the center of the area of the collision area 43 is 0.0325M 2 becomes. Then, 4m in the spray nozzles 41 of the one 3 / m 2 in order to ensure a water flow rate of / min., 0.26 m 3 / min (= 4m 3 / m 2 /Min×0.0325M 2 is the amount of water) is required.
[0085]

　was cooled with a cooling device 15 in the hot-rolled steel sheet 10a of the above embodiment to a low temperature of about 200 ° C., for example in a case the cooling stop temperature in the cooling device 15 is not low temperature, there is no need to inject the coolant from all of the spray nozzles 41 of the side spray device 40. In such a case, in consideration of the cooling uniformity in the width direction, and controls the association unit P for each spray nozzle pair 42, the same, is only injected cooling water from the spray nozzle pairs 42 required for cooling, unnecessary cooling from the spray nozzle pairs 42 is possible to not inject cooling water, adjusting the cooling capacity of the side spray device 40. Therefore, the side spray device 40, for each of a plurality of spray nozzle pairs 42, it is preferable to provide a valve for controlling the presence or absence of the supply of the cooling water.
[0086]
　Also, in the case of providing a valve for controlling the presence or absence of the supply of cooling water to the side spray device 40 may be a cooling small zone f described above the area where the valve is provided. Even such a case, each cooling small zone f, preferably to satisfy the condition of the above-described embodiment. That is, the cooling small zone f valve is provided, is formed meeting part P of the impact zone 43, 43 in the spray nozzle pair 42 as shown in FIG. 4, further association portion P, the above equation (1) together are positioned within associated zone E having a width satisfying, association portion P of the spray nozzle pairs 42, 42 adjacent to the conveying direction, spacing Q in the width direction of P is, the conveying direction over the length R of the collision area 43 to become. Further, in the cooling small zone f, Figure 9, the association unit P as shown in FIG. 10 are arranged in a staggered manner.
[0087]

　In the cooling device 15 of the above embodiment, when draining of the plate clean water 22 after cooling in the upper cooling device 20, but have used dedicated drained device 30, FIG. 11 as shown in, it abolished the draining device 30 of such a dedicated spray nozzle pairs 42 of side spray device 40 may be installed. That is, in addition to the spray nozzle pair 42 that is used to cool the actual hot rolled steel sheets 10a, upstream in the conveyance direction, the spray nozzle pairs 42 may be provided for draining.
[0088]
　In the example shown in this FIG. 11, on the downstream side on both sides of the upper cooling device 20, is configured as a facility spray nozzle pair 42 is more established, width and thickness of the hot rolled steel sheet 10a for cooling, conveying speed , depending on the type of steel, the spray nozzle pairs 42 used for draining, or switching control between the spray nozzle pairs 42 used for cooling, by controlling the number of injection as needed, dedicated drained device 30 it is not necessary to install, may be a good facility in versatility. As another example of using this manner the spray nozzle pairs 42 for draining, abolished the dedicated drained device 50, the spray nozzle pairs 42 of side spray device 40 may be installed.
[0089]
　Having described the preferred embodiments of the present invention with reference to the accompanying drawings, the present invention is not limited to such an example. Those skilled in the art within the scope of the spirit as set forth in the claims, it would be appreciated by the can conceive changes and modifications are embraced in the technical scope of the present invention as for their It is understood that.
Example 1
[0090]
　First, the effect of forming an association portion P of the present invention will be described with reference to examples and comparative examples. In this verification, the simulation was performed using a side spray device 40 shown in FIGS. 2-6.
[0091]
　Common conditions of the Examples and Comparative Examples of the present verification is as follows. The thickness of the hot-rolled steel sheet 10a to be cooled is 2.5 mm, the width of the hot-rolled steel sheet 10a is 1500 mm. Width D of the steel plate conveyance region 10 is 2000 mm. The side spray device 40, there spray nozzle 41 is present 84, i.e. a spray nozzle pairs 42 is 42 pairs. The height h installation of the spray nozzles 41 is 600 mm. Using a flat spray nozzle for each spray nozzle 41, the spraying angle theta 1 is 12 degrees, a spray installation angle theta 2 is 62 degrees. Injection pressure of the cooling water jetted from the spray nozzle 41 is 0.5 MPa, water density of the cooling water is 4.2 m 3 / m 2 / min, quantity of cooling water is 360 L / min, in the conveying direction of the impact region 43 length R is 69mm.
[0092]
　In this verification, in the first embodiment of the present invention as shown in FIG. 12 (a), the association unit P is formed in the impact region 43 of the spray nozzle pairs 42. In contrast, in Comparative Example 1 as shown in FIG. 12 (b), overlap collision area 43, 43 of the spray nozzle pairs 42, the proximal end portion 43b in the overlapping portion, the spacing 43b is 30 mm. In Comparative Example 2, as shown in FIG. 12 (c), do not overlap collision area 43, 43 of the spray nozzle pairs 42, the proximal end portion 43b, spacing 43b is 30 mm.
[0093]
　In Example 1, the association portion P of the meeting zone E satisfying the above formula (1), the association unit P formed in 42 places in the conveying direction is dispersed in the width direction are arranged, further adjacent to the conveying direction, P the spacing Q of the width direction of, and the conveying direction of the length R more impact area 43. Specifically, in a spray nozzle pairs 42, the horizontal distance d1 between the end portion of the injection port 41a and the steel sheet conveyance area 10 of one spray nozzle 41, the injection port 41a and the steel sheet transfer area 10 of the other spray nozzles 41 the total horizontal distance d (= d1 + d2) of the horizontal distance d2 between the end portion varied between 0 ~ 500 mm, are arranged meeting part P as described above.
[0094]
　Further, in Comparative Example 1, the overlapping portion of the collision area 43, 43 of the spray nozzle pair 42, the widthwise center point C1 is the width direction to be the same position in response to the meeting part P in Embodiment 1 dispersed are formed. Similarly, in Comparative Example 2, a portion not overlapping the impact area 43 of the spray nozzle pair 42, as the width-direction center point C2 becomes the same position in response to the meeting part P in Embodiment 1 It is formed by dispersing in the width direction.
[0095]
　In conditions such as above, the cooling start temperature of the hot-rolled steel sheet 10a in the side spraying devices 40 and 600 ° C., the target temperature after cooling the hot rolled steel sheet 10a (coiling temperature of hot-rolled steel sheet 10a in the winding device 16) simulation was performed as 300 ℃ a. Then, Example 1, Comparative Example 1, Comparative Example 2, by measuring the coiling temperature of hot-rolled steel sheet 10a in the winding device 16, the maximum temperature and the minimum in the width direction of the width direction deviation (hot-rolled steel sheet 10a the temperature difference of) were measured.
[0096]
　As a result, in Example 1, the temperature in the width direction of the hot-rolled steel sheet 10a is 300 ° C. ± 5 ° C., the temperature deviation was 10 ° C.. In contrast, in Comparative Example 1, the temperature in the width direction of the hot-rolled steel sheet 10a is 300 ° C. ± 30 ° C., the temperature deviation was 60 ° C.. In Comparative Example 2, the temperature in the width direction of the hot-rolled steel sheet 10a is 300 ° C. ± 25 ° C., the temperature deviation was 50 ° C..
[0097]
　Therefore, when forming the association unit P in a spray nozzle pairs 42 as in the first embodiment of the present invention, as compared with the case of not forming an association portion P as in Comparative Examples 1 and 2, hot-rolled steel sheet 10a after cooling width temperature deviation can be reduced, it was found that it is possible to uniformly cool the hot-rolled steel sheet 10a in the width direction.
Example 2
[0098]
　Then, in the present invention, the width W of the meeting zone E of meeting part P is located satisfies the above formula (1), namely to satisfy the above-mentioned Lf / Ln ≦ 2 (FIG. 7), the examples and comparative It will be described with reference to examples. In this verification, the simulation was performed using a side spray device 40 shown in FIGS. 2-6.
[0099]
　Common conditions of the Examples and Comparative Examples of the present verification is as follows. The thickness of the hot-rolled steel sheet 10a to be cooled is 2.5 mm, the width of the hot-rolled steel sheet 10a is 1500 mm. Width D of the steel plate conveyance region 10 is 2000 mm. The side spray device 40, there spray nozzle 41 is present 84, i.e. a spray nozzle pairs 42 is 42 pairs. The height h installation of the spray nozzles 41 is 600 mm. With flat spray nozzles on each spray nozzle 41.
[0100]
　Example 2 of this verification, Example 3, Comparative Example 3, the association unit P in the collision area 43, 43 of the spray nozzle pairs 42 are formed, respectively. The spraying angle theta of each spray nozzle 41 1 and spray installation angle theta 2 to change the, it was varied Lf / Ln. Specifically, the Lf / Ln Example 2 of the present invention 1.9, the Lf / Ln of Example 3 of the present invention 2.0, was 2.5 Lf / Ln of Comparative Example 3.
[0101]
　In Example 2, spraying angle theta of each spray nozzle 41 1 of 14 degrees, a spray installation angle theta 2 as 61 °, was 1.9 Lf / Ln. Further, in Example 2, the injection pressure of the cooling water jetted from the spray nozzle 41 is 0.5 MPa, water density of the cooling water is 4.2 m 3 / m 2 / min, quantity of cooling water is 308L / min, the length R of the conveying direction of the impact region 43 is 62 mm.
[0102]
　In Example 3, spraying angle theta of each spray nozzle 41 1 of 16 degrees, a spray installation angle theta 2 as 59 °, was 2.0 Lf / Ln. Further, in Example 2, the injection pressure of the cooling water jetted from the spray nozzle 41 is 0.5 MPa, water density of the cooling water is 4.2 m 3 / m 2 / min, quantity of cooling water is 320L / min, the length R of the conveying direction of the impact region 43 is 61 mm.
[0103]
　In contrast, in Comparative Example 3, spraying angle theta of each spray nozzle 41 1 of 25 degrees, a spray installation angle theta 2 as 50 °, was 2.5 Lf / Ln. In Comparative Example 3, the injection pressure of the cooling water jetted from the spray nozzle 41 is 0.5 MPa, water density of the cooling water is 4.2 m 3 / m 2 / min, quantity of cooling water is 367L / min, the length R of the conveying direction of the impact region 43 is 58 mm.
[0104]
　In Example 2, Example 3, Comparative Example 3, in each meeting zone E, the association unit the association portion P formed in 42 places in the conveying direction and arranged to be dispersed in the width direction, adjacent to the conveying direction P, and interval Q in the width direction of P, have the transport direction of the length R over 70mm collision region 43. Note that, specifically, in a spray nozzle pairs 42, the horizontal distance d1 between the end portion of the injection port 41a and the steel sheet conveyance area 10 of one spray nozzle 41, the injection port 41a and the steel plate conveyance region of the other of the spray nozzle 41 the total horizontal distance d of the horizontal distance d2 between the end of the 10 (= d1 + d2) and varied between 0 ~ 500 mm, are arranged meeting part P as described above.
[0105]
　In conditions such as above, the cooling start temperature of the hot-rolled steel sheet 10a in the side spraying devices 40 and 600 ° C., the target temperature after cooling the hot rolled steel sheet 10a (coiling temperature of hot-rolled steel sheet 10a in the winding device 16) simulation was performed as 300 ℃ a. Then, Example 2, Example 3, Comparative Example 3, to measure the coiling temperature of hot-rolled steel sheet 10a in the winding device 16, the maximum temperature and the minimum in the width direction of the width direction deviation (hot-rolled steel sheet 10a the temperature difference of) were measured.
[0106]
　As a result, Example 2, Example 3, the width direction of the temperature of 300 ° C. ± 5 ° C. Each hot-rolled steel sheets 10a, the temperature deviation was 10 ° C.. In contrast, in Comparative Example 3, the temperature in the width direction of the hot-rolled steel sheet 10a is 300 ° C. ± 25 ° C., the temperature deviation was 50 ° C..
[0107]
　Therefore, the embodiment of the present invention 2,3 (Lf / Ln ≦ 2), as compared with the case of Comparative Example 3 (Lf / Ln> 2), the width direction temperature deviation hot-rolled steel sheet 10a after cooling small it can be, was found to be uniformly cooled hot rolled steel sheet 10a in the width direction. In other words, Lf / from the equation Ln ≦ 2 in the width W of the meeting zone E (1) is derived and to distribute the associated portion P in the meeting zone E, uniformly hot-rolled steel sheet 10a in the width direction it has been found that can be cooled.
Example 3
[0108]
　Then, in the present invention, association portion P of the spray nozzle pair 42 adjacent to the conveying direction, the spacing Q in the width direction of P is the transport direction of the length R more impact region 43, i.e. the association unit P and the surrounding effects range the temperature difference is on the periphery (Fig. 8) will be described with reference to examples and comparative examples. In this verification, the simulation was performed using a side spray device 40 shown in FIGS. 2-6.
[0109]
　Common conditions of the Examples and Comparative Examples of the present verification is as follows. The thickness of the hot-rolled steel sheet 10a to be cooled is 2.5 mm, the width of the hot-rolled steel sheet 10a is 1500 mm. Width D of the steel plate conveyance region 10 is 2000 mm. The side spray device 40, there spray nozzle 41 is present 84, i.e. a spray nozzle pairs 42 is 42 pairs. The height h installation of the spray nozzles 41 is 600 mm. Using a flat spray nozzle for each spray nozzle 41, the spraying angle theta 1 is 12 degrees, a spray installation angle theta 2 is 62 degrees. Injection pressure of the cooling water jetted from the spray nozzle 41 is 0.5 MPa, water density of the cooling water is 4.2 m 3 / m 2 / min, quantity of cooling water is 360 L / min, in the conveying direction of the impact region 43 length R is 69mm.
[0110]
　Comparative Example 4 Example 4 of the present verification, association portion P in the collision area 43, 43 of the spray nozzle pairs 42 are formed, respectively. The association unit P adjacent to the conveying direction, was varied interval Q in the width direction of the P. Specifically, in the fourth embodiment of the present invention, the association unit P, and interval Q in the width direction of P, and the conveying direction of the length R is greater than 70mm of the collision area 43. That is, in Example 4, is greater than 1 n in FIG. In contrast, in Comparative Example 4, the association unit P, and interval Q in the width direction of P, was shorter than the length R of the conveying direction of the impact region 43 65 mm. That is, in Comparative Example 4, less than 1 n in FIG.
[0111]
　In Comparative Example 4 Example 4, in each meeting zone E, are arranged by dispersing the association unit P formed in 42 places in the conveying direction in the width direction. In Comparative Example 4 Example 4, the spray nozzle pairs 42, the horizontal distance d1 between the end portion of the injection port 41a and the steel sheet conveyance area 10 of one spray nozzle 41, the injection port 41a of the other of the spray nozzle 41 and a total horizontal distance d (= d1 + d2) of the horizontal distance d2 between the end portion of the steel plate conveyance region 10 varied between 0 ~ 500 mm, are arranged meeting part P as described above.
[0112]
　In conditions such as above, the cooling start temperature of the hot-rolled steel sheet 10a in the side spraying devices 40 and 600 ° C., the target temperature after cooling the hot rolled steel sheet 10a (coiling temperature of hot-rolled steel sheet 10a in the winding device 16) simulation was performed as 300 ℃ a. Then, in Example 4 and Comparative Example 4, measuring the coiling temperature of hot-rolled steel sheet 10a in the winding device 16, (the difference between the maximum temperature and the minimum temperature in the width direction of the hot rolled steel sheet 10a) the width direction deviation It was measured.
[0113]
　As a result, in Example 4, the temperature in the width direction of the hot-rolled steel sheet 10a is 300 ° C. ± 5 ° C., the temperature deviation was 10 ° C.. In contrast, in Comparative Example 4, the temperature in the width direction of the hot-rolled steel sheet 10a is 300 ° C. ± 20 ° C., the temperature deviation was 40 ° C..
[0114]
　Therefore, in Example 4 of the present invention (association unit P, when the interval Q in the width direction of P is greater than the length R of the conveying direction of the impact region 43), the case of Comparative Example 3 (interval Q length R compared to smaller cases), the width direction temperature deviation of hot-rolled steel sheet 10a after cooling can be reduced, it was found that it is possible to uniformly cool the hot-rolled steel sheet 10a in the width direction.
Industrial Applicability
[0115]
　The present invention is useful in cooling the hot-rolled steel sheet after finish rolling of a continuous hot rolling process.
DESCRIPTION OF SYMBOLS
[0116]
　　1 continuous hot rolling equipment
　　5 slab
　　10 steel transfer region
　　10a hot-rolled steel sheet
　　11 heating furnace
　　12 widthwise rolling mill
　　13 rough rolling mill
　　14 finishing mill
　　15 cooling device
　　16 retractor
　　conveyor 17 rolls
　　20 the upper cooling device
　　21 the cooling water nozzles
　　22 plate clean water
　　30, 50 draining device
　　31, 51 a spray device
　　40 side spray device
　　41 spray nozzles
　　41a injection port
　　42 spray nozzle pairs
　　43 collision region
　　43a the distal end portion
　　43b proximal end portion
　　E meeting zones
　　e1 ~ e8 meeting small zone
　　F cooling zone
　　f1 ~ f3 cooling small zone
　　f11 ~ f32 split cooling small zone
　　P meeting part

The scope of the claims
[Requested item 1]
The hot-rolled steel sheet after finish rolling of a continuous hot rolling step to a method of cooling,
when the hot-rolled steel sheet to a region of the steel plate conveyance area occupied on the transport roll, both sides in the width direction side of the steel plate conveyance region a pair of spray nozzles are arranged, and, the spray nozzle pairs are pairs arranged in the conveying direction of the hot-rolled steel sheet, with respect to the steel plate conveyance region, the cooling water from the spray nozzles in the width direction of the steel sheet conveyance region injection to the hot-rolled steel sheet is cooled,
the collision area of the steel plate conveyance area of the cooling water sprayed from the spray nozzle, the distal end portion of the injection direction is located at the end of the steel plate conveyance region, proximal end parts are located inside the steel plate conveyance region,
in said spray nozzle pairs, proximal ends of the two said impact region, and forming an association unit to match the width direction, cooling the hot rolled steel sheet Method.
[Requested item 2]
The association unit, located within the associated zone is divided into the center in the width direction of the steel plate conveyance region,
the width of the associated zone satisfies the following formula (1),
the association portion of said spray nozzles adjacent pair in the transport direction the width direction of the gap, wherein said at impact area conveying direction over the length of the cooling method of hot rolled steel sheet according to claim 1.
W ≦ (D + 2d) - (D + d) sin [theta 2 / sin (theta 1 + theta 2 ) · · · (1)
where,
W: the width of the associated zone
D: the width of the steel sheet conveyance area
d: injection port of the spray nozzle and its front horizontal distance between the end portion of the steel plate conveyance region of
theta 1 : spraying angle
theta 2 : forming a spray installation angle (from the injection port of the perpendicular line and the spray nozzle of the injection port of the spray nozzle of the line connecting the widthwise center of the steel plate conveyance region corner)
[Requested item 3]
The cooling zone in which a plurality toward a pair of spray nozzle pairs of the steel sheet conveyance region cooling water is injected is divided into a plurality of cooling sub-zone in the conveying direction,
wherein the cooling small zone N pairs (N is an integer) spray nozzle pair is disposed,
the associated zone is divided into said N associative small zone at equal intervals in the width direction,
the cooling in the meeting small zone in a small zone, is arranged one of said associated portions respectively ,
the meeting part of the cooling sub-zone, toward the downstream side from the upstream side in the transport direction, are disposed towards the meeting the association small zone of the other end from the small zone of one end of the meeting zone characterized Rukoto cooling method of hot rolled steel sheet according to claim 2.
[Requested item 4]
The cooling small zone, k pieces in the conveying direction (k is a divisor of N) is divided into a divided cooling small zone of,
and in the divided cooling small zone of the i-th in the conveying direction (i is an integer from 1 to k) the association unit, the direction from the first one end portion side of the associated zone N th other end side, jk + i th from the i-th (j is from 1 to (N / k-1) characterized in that it is arranged to an integer), the cooling method of hot rolled steel sheet according to claim 3.
[Requested item 5]
The cooling of the hot rolled steel sheet by the cooling water from the spray nozzle, characterized in that it is performed in the nucleate boiling region, the cooling method of hot rolled steel sheet according to any one of claims 1-4.
[Requested item 6]
The hot-rolled steel sheet after finish rolling of a continuous hot rolling process and an apparatus for cooling,
when the hot-rolled steel sheet to a region of the steel plate conveyance area occupied on the transport roll, with respect to the steel plate conveyance region, the steel plate conveyance spray nozzles for injecting cooling water to the width direction of the region is disposed in a pair on both sides in the width direction side of the steel plate conveyance region, and, the spray nozzle pairs are pairs arranged in the conveying direction of the hot rolled steel sheet,
said spray nozzle, in the impact region in the steel plate conveyance area of the cooling water sprayed from the spray nozzle, the distal end portion of the injection direction is located at the end of the steel plate conveyance region, proximal end of the steel plate conveyance region is arranged to be positioned inside
the spray nozzle pair is characterized in that the proximal end portion of two of the impact area is arranged so as to form an association unit to match the width direction, the hot rolled cooling apparatus of steel plate.
[Requested item 7]
The association unit, located within the associated zone is divided into the center in the width direction of the steel plate conveyance region,
the width of the associated zone satisfies the following formula (1),
the said spray nozzle pairs adjacent to the conveying direction, respectively intervals in the width direction of the meeting portion, characterized in that it is arranged such that over the length of the conveying direction of the impact region, the cooling device for a hot-rolled steel sheet according to claim 6.
W ≦ (D + 2d) - (D + d) sin [theta 2 / sin (theta 1 + theta 2 ) · · · (1)
where,
W: the width of the associated zone
D: the width of the steel sheet conveyance area
d: injection port of the spray nozzle and its front horizontal distance between the end portion of the steel plate conveyance region of
theta 1 : spraying angle
theta 2 : forming a spray installation angle (from the injection port of the perpendicular line and the spray nozzle of the injection port of the spray nozzle of the line connecting the widthwise center of the steel plate conveyance region corner)
[Requested item 8]
The cooling zone in which a plurality toward a pair of spray nozzle pairs of the steel sheet conveyance region cooling water is injected is divided into a plurality of cooling sub-zone in the conveying direction,
wherein the cooling small zone N pairs (N is an integer) spray nozzle pair is disposed,
the associated zone is divided into said N associative small zone at equal intervals in the width direction,
the cooling in the meeting small zone in a small zone, is arranged one of said associated portions respectively ,
the meeting part of the cooling sub-zone, toward the downstream side from the upstream side in the transport direction, are disposed towards the meeting the association small zone of the other end from the small zone of one end of the meeting zone characterized Rukoto cooling device for a hot-rolled steel sheet according to claim 7.
[Requested item 9]
The cooling small zone, k pieces in the conveying direction (k is a divisor of N) is divided into a divided cooling small zone of,
and in the divided cooling small zone of the i-th in the conveying direction (i is an integer from 1 to k) the association unit, the direction from the first one end portion side of the associated zone N th other end side, jk + i th from the i-th (j is from 1 to (N / k-1) characterized in that it is arranged to an integer), the cooling device for a hot-rolled steel sheet according to claim 8.