TWI446975B - System for cooling steel sheet, manufacturing apparatus of hot-rolled steel sheet, and manufacturing method of steel sheet - Google Patents

Description

Steel plate cooling device, hot rolled steel plate manufacturing device, and steel plate manufacturing method

The present invention relates to a cooling device for a steel sheet used in a hot-rolled steel sheet manufacturing line, a manufacturing device for a hot-rolled steel sheet, and a method for producing a steel sheet. Specifically, it relates to a cooling device for a steel sheet excellent in cooling water drainage performance, a manufacturing device for a hot rolled steel sheet, and a method for producing a steel sheet using the same.

Steels used for automobiles and structural materials are required to have mechanical properties of excellent strength, workability, and toughness. In order to comprehensively improve these mechanical properties, the miniaturization of the steel structure is an effective method. Therefore, everyone is developing a method for obtaining steel with fine structure. Further, if the structure can be made fine, even if the amount of the alloying elements is reduced, a high-strength hot-rolled steel sheet having excellent mechanical properties can be produced.

The method of miniaturization of the structure, in the hot rolling and rolling, especially in the latter stage, is subjected to high-pressure rolling, so that the Worstian iron particles are greatly deformed, and the transformation density is increased, thereby pursuing the miniaturization of the fat particles after cooling. The method is well known to everyone. Next, from the viewpoint of suppressing the recrystallization and recovery of the Worthite iron and promoting the metamorphism of the fertilizer body, it is an effective method to cool the steel sheet to 600 to 700 ° C in a short time after the rolling. That is, after the hot rolling and rolling, it is effective to provide a cooling device which can be cooled faster than the conventional one to perform the rapid cooling of the steel sheet after the rolling. Next, when the steel sheet after the rolling is subjected to rapid cooling, in order to increase the cooling capacity, the amount of cooling water per unit area of the steel sheet injection can be increased, that is, the flow density can be increased.

However, as described above, when the amount of cooling water and the flow density are increased, the amount of water (stagnation water) remaining on the upper surface of the steel sheet increases due to the relationship between the water supply and the drainage. On the other hand, on the lower side of the steel sheet, the retained water between the lower guide portion and the steel sheet increases. This type of stagnant water is used for water after the steel sheet is cooled. In order to supply the water supplied from the cooling nozzle to the steel sheet to ensure the cooling capacity, it should be discharged as soon as possible. In addition, since the water-repellent water layer is retained, if it is thick, resistance will occur, and water from the cooling nozzle will not efficiently reach the steel sheet. Next, the retained water flows from the central portion of the steel sheet to the end portion, and the flow rate increases toward the end portion of the steel sheet. When the amount of retained water increases, the difference in cooling in the width direction of the steel sheet increases. In addition, if the amount of retained water is excessively increased, stagnant water may also appear on the upper guide portion, and the front end of the cooling nozzle is flooded.

As described above, since it is effective to perform rapid cooling as soon as possible after hot rolling, it is necessary to perform cooling immediately after the work rolls of the final rolling stand of the hot rolling mill. That is, cooling water is sprayed on the steel sheet existing inside the final rolling mill housing of the hot rolling mill train to be cooled. Such cooling is as described in Patent Document 1.

[Patent Document 1] Japanese Patent No. 4029871

Among the cooling water sprayed to the upper side of the steel sheet, most of them are moved in the width direction of the steel sheet, and flow to the lower side to be discharged. However, in the case of the inside of the casing of the final rolling stand of the hot rolling mill, the side walls of the standing portion of the casing or the like may be disposed on both sides in the width direction of the steel sheet. At this time, when the cooling water is sprayed on the upper surface of the steel sheet, the side wall may hinder the drainage of the cooling water and the drainage impact side wall and the part of the cooling water moving upward may be retained in the upper guide portion to flood the front end of the cooling nozzle. Patent Document 1 describes an invention for improving the drainage performance of the upper guide portion. However, when a large amount of cooling water is used to improve the cooling performance, it is also important to improve the drainage performance from both sides in the width direction of the steel sheet.

Therefore, in view of the above problems, an object of the present invention is to provide a cooling device having excellent drainage properties in a hot-rolled steel sheet manufacturing line, a manufacturing apparatus for hot-rolled steel sheets, and a method for producing a steel sheet.

Hereinafter, the present invention will be described.

In order to solve the above problems, the invention according to claim 1 provides a cooling device which is disposed on the lower side of the final rolling table of the hot rolling mill, and is provided to be capable of cooling the steel sheet to be conveyed on the conveying roller. A cooling device for a steel plate of a plurality of cooling nozzles, wherein the cooling nozzles are disposed at positions on the upper side and the lower side of the passage portion of the steel sheet to spray cooling water toward the steel plate passing portion, and have a uniform cooling width disposed in the cooling nozzles. For the position of the outer side of the steel sheet in the width direction, a rectifying means for draining and rectifying the cooling water sprayed by the cooling nozzle is performed.

Here, the "uniform cooling width" of the cooling nozzle refers to the size of the steel sheet in the width direction of the steel sheet to be uniformly cooled in the nature of the arranged cooling nozzle group. Specifically, it is generally the same as the width of the largest steel sheet that can be manufactured by the steel sheet manufacturing apparatus.

In addition, "cooling water" refers to cooling water used as a cooling medium, and it is not necessarily so-called pure water, and it may be water containing industrial impurities such as impurities which are inevitably mixed.

The invention described in claim 2 is the cooling device according to the first aspect of the invention, characterized in that the upper surface guide portion is disposed on the upper surface side of the steel sheet passing portion, and the rectifying means is disposed in the ratio The uniform cooling width of the cooling nozzle is one of the positions of the outer side of the steel sheet in the width direction and the other side is opposite to the pair of members. The arrangement of the opposite members is the narrowest at the upper end, and the lower end is wider than the upper end and the upper end. It is disposed in contact with or close to the upper guiding portion, and the lower end is located below the upper guiding portion.

Here, "proximity" means an arrangement that does not have to be in contact, but should be as close as possible.

The invention described in claim 3 is the cooling device according to claim 1 or 2, wherein the rectifying means prevents the cooling water sprayed from the cooling nozzle from being in the width direction of the upper guiding portion The means on the outside of the end reaches the upper guide.

The invention described in claim 4 is the cooling device according to the first to third aspects of the invention, characterized in that the rectifying means includes a gas injection device that injects gas downward.

The invention described in claim 5 is the cooling device according to the first aspect of the invention, characterized in that the rectifying means has a means for diverging the drainage into upper and lower portions for guidance, and A means of drainage that can be diverted to the opening of the upper water inflow.

In order to solve the above problems, the invention described in claim 6 is provided with a hot-rolled steel sheet including a hot rolling mill train and a cooling device according to any one of the first to fifth aspects of the patent application. The manufacturing apparatus is characterized in that a side wall is erected at a position further outward in the width direction of the steel sheet of the cooling device.

The invention described in claim 7 is the apparatus for manufacturing a hot-rolled steel sheet according to claim 6, wherein the final rolling stand of the hot rolling mill includes: a casing for holding the work roll The housing has a pair of standing portions including a portion of the upper guiding portion therebetween, and the standing portion is the aforementioned side wall.

The invention described in the eighth aspect of the invention is characterized in that the invention provides a hot-rolled steel sheet manufacturing apparatus of the hot-rolling mill train and the cooling device according to any one of the first to fifth aspects of the invention, which is characterized in that A side wall is erected at a position further outward in the width direction of the steel sheet of the cooling device, and at least a part of the rectifying means of the cooling device is disposed to contact the side wall.

The invention according to the ninth aspect of the invention is characterized in that: the hot-rolled steel sheet manufacturing apparatus of the hot rolling mill, and the cooling apparatus described in any one of the first to fifth aspects of the patent application, characterized in that The side wall is erected at a position further outward than the width direction of the steel sheet in the cooling device, and the rectifying means of the cooling device is disposed so as to have a gap with the side wall.

In order to solve the above problems, the invention of the invention of claim 10 provides a steel sheet for manufacturing a steel sheet by a steel sheet manufacturing apparatus according to any one of the sixth to ninth aspects of the invention. Production method.

In order to solve the above problems, the invention of the invention of claim 11 is a method for producing a steel sheet by using a hot-rolled steel sheet manufacturing apparatus according to any one of the sixth to ninth aspects of the invention. The method comprises the steps of: performing a dressing rolling process with a maximum pressure drop rate in a final rolling stand in a hot rolling mill train, and cooling by a cooling device.

In order to solve the above-mentioned problem, the invention of claim 12 is a method for producing a steel sheet by using a hot-rolled steel sheet manufacturing apparatus according to any one of the sixth to ninth aspects of the invention. The manufacturing apparatus is provided with a pinch roller on the step side below the cooling device, and after the front end of the steel plate passes through the pinch roller, cooling is started by the cooling device.

According to the present invention, it is possible to provide a cooling device having excellent drainage properties of a hot-rolled steel sheet manufacturing line, a manufacturing apparatus for hot-rolled steel sheets, and a method for producing a steel sheet. Further, by this, the amount of cooling water can be increased, so that quenching after rolling can be further promoted, and a steel sheet excellent in mechanical properties can be produced.

The above-described actions and gains of the present invention are known from the following description for the purpose of carrying out the invention. Hereinafter, the description of the present invention will be made with reference to the embodiments shown in the drawings. However, the invention is not limited to the embodiments.

Fig. 1 is a partial schematic view showing a manufacturing apparatus 10 for a hot-rolled steel sheet including the cooling device 20 of the first embodiment. In the first drawing, the steel sheet 1 is conveyed from the left side (upstream side, upper step side) to the right side (downstream side, lower step side) in the drawing, and the drawing is vertically oriented. The upstream side (upper step side) and the downstream side (lower step side) direction are described as the through-plate direction, and the plate width direction of the steel sheet passing through the perpendicular direction is described as the steel plate width direction. In addition, the description of the repeated symbols is omitted for the sake of brevity.

As shown in Fig. 1, the hot-rolled steel sheet manufacturing apparatus 10 includes a hot rolling mill train 11, a cooling device 20, conveyance rollers 12, 12, ..., and a pinch roller 13. In addition, the illustration and description are omitted. However, on the step side of the hot rolling mill row 11, a heating furnace, a rough rolling mill train, and the like are disposed to trim the conditions of the steel sheet entering the hot rolling mill train 11. On the other hand, on the step side below the pinch roller 13, various devices such as other cooling devices, coilers, and the like are disposed to carry out the shipment of the steel sheets in a coil shape.

The hot rolled steel sheet is roughly produced in the following manner. That is, a thick rod which is taken out from the heating furnace and rolled into a specific thickness by a rough rolling mill is continuously rolled into a specific thickness by the hot rolling mill train 11 while controlling the temperature. Thereafter, rapid cooling is performed in the cooling device 20. Here, the cooling device 20 is disposed on the final rolling table 11g of the hot rolling mill train 11 in a manner of supporting the rolling roller so as to be close to the rolling roller 11gw and 11gw (see FIG. 2) of the final rolling table 11g. Inside the housing 11gh. Next, the pinch roller 13 is cooled to a specific coiling temperature by another cooling device, and wound up in a coil shape by a coiler.

In the following, the manufacturing apparatus 10 (hereinafter also referred to simply as "the manufacturing apparatus 10") of the hot-rolled steel sheet is described in detail, including the cooling device 20. Fig. 2 is an enlarged view of a portion including the cooling device 20 of Fig. 1. Fig. 2(a) is an enlarged view of the entire cooling device 20, and Fig. 2(b) is an enlarged view of the vicinity of the final rolling table 11g. Figure 3 is a perspective sectional view of III-III of Figure 2(a). Therefore, in Fig. 3, the vertical direction of the manufacturing apparatus 10 is on the lower surface of the drawing, and the left and right sides of the drawing are in the width direction of the steel sheet, and the far/near direction of the drawing is the direction of the through sheet.

In the hot rolling mill row 11 of the present embodiment, as can be seen from Fig. 1, seven rolling mills (11a, 11b, 11c, ..., 11g) are arranged in the direction of the through-plate. Each of the rolling mills 11a, 11b, ..., 11g is used to form a so-called rolling mill for each rolling stand, and the rolling conditions such as the pressing ratio are set in accordance with conditions such as the thickness, mechanical properties, and surface quality necessary for the final product. Here, the pressure ratio under each rolling table is set in such a manner as to conform to the performance of the steel plate to be produced. However, rolling under high pressure causes the Worthfield iron particles to undergo large deformation and increase the transformation density to seek cooling. From the viewpoint of the miniaturization of the ferrite particles, the pressure ratio under the final rolling table of 11 g should be large.

The rolling mill of each rolling stand has: one of the pair of work rolls (11aw, 11aw, ..., 11fw, 11fw, 11gw, 11gw) which is actually clamped and pressed down, and is arranged to contact the outer edge of the work roll A pair of wheel assist rollers (11ab, 11ab, ..., 11fb, 11fb, 11gb, 11gb). Further, the rolling mill has a casing (11ah, ..., 11fh, 11gh) having a work roll and a wheel-assisted roller on the inside to form a roll mill casing and supporting the roll roller. The casing has a standing portion that is erected (when the final rolling stand 11g is the standing portion 11gr, 11gr of Fig. 3). In other words, the erected portion of the casing can be erected so as to sandwich the steel plate and the lower guide portion 40 in the width direction of the steel sheet.

Here, the distance between the shaft center of the work roll 11gw indicated by L1 in the second drawing (a) and the step side end surface of the housing upright portions 11gr and 11gr is larger than the radius r1 of the work roll 11gw. Therefore, at a portion corresponding to L1-r1, one portion of the cooling device 20 can be disposed as will be described later. That is, one portion of the cooling device 20 can be disposed in such a manner as to be inserted inside the casing 11gh.

Further, as shown in Fig. 3, the cooling device 20 is inserted into the portion between the housing upright portions 11gr and 11gr, and the housing used as the side wall exists on the extension line of the guide plate portion 40 in the width direction of the lower portion of the guide portion 40 of the cooling device 20. Stands 11gr, 11gr. Next, a specific gap is formed between the end portion of the lower guide portion 40 in the width direction of the steel sheet and the housing standing portions 11gr and 11gr.

Next, the cooling device 20 will be described. The cooling device 20 includes: upper water supply means 21, 21, ..., lower water supply means 22, 22, ..., upper guide parts 30, 30, ..., lower guide parts 40, 40, .. And rectification means 50, 50.

The upper water supply means 21, 21, ... are means for supplying cooling water to the upper side of the steel sheet 1, and are provided in the cooling headers 21a, 21a, ..., and disposed in the respective cooling headers 21a, The plurality of rows of conduits 21b, 21b, ..., and the cooling nozzles 21c, 21c, ... installed at the tips of the conduits 21b, 21b, ....

In the present embodiment, it can be seen from FIGS. 2 and 3 that the cooling header 21a extends in the width direction of the steel sheet, and the cooling headers 21a, 21a, ... are juxtaposed in the direction of the through-plate. .

The duct 21b is a plurality of thin pipes that are branched from the respective cooling headers 21a, and the open end thereof faces the upper surface side of the steel sheet. The plurality of conduits 21b, 21b, ... are arranged in a comb-tooth shape along the longitudinal direction of the tube of the cooling header 21a, that is, in the width direction of the steel sheet.

Cooling nozzles 21c, 21c, ... are installed at the front ends of the respective ducts 21b, 21b, .... The cooling nozzles 21c, 21c, ... of the present embodiment are flat spray nozzles which can form a fan-shaped cooling water jet (for example, a thickness of about 5 mm to 30 mm). Fig. 4 and Fig. 5 are schematic views showing the formation of a cooling water jet on the surface of the steel sheet by the cooling nozzles 21c, 21c, .... Figure 4 is a transmission diagram. Fig. 5 is a schematic view showing an impact form of the jet when striking the surface of the steel sheet. In Fig. 5, the white circles indicate the positions directly below the cooling nozzles 21c, 21c, ..., and the thick lines indicate the impact position and shape of the cooling water jet. In Fig. 4 and Fig. 5, the direction of the through-plate and the width direction of the steel sheet are simultaneously shown.

4 and 5, in the present embodiment, the adjacent nozzle rows are arranged such that the position in the width direction of the steel sheet is shifted, and secondly, the adjacent nozzle rows are positioned in the same direction as the width direction of the steel sheet. It is a so-called checkerboard arrangement.

In the present embodiment, the cooling nozzles 21c, 21c, ... are disposed such that the cooling water jet flows at least twice in the width direction of the steel sheet on the steel sheet surface. That is, a certain point ST of the steel sheet is moved along the straight arrow of FIG. In this case, the nozzle row A is secondary (A1, A2), the nozzle row B is secondary (B1, B2), and the nozzle row C is secondary (C1, C2), ..., in each nozzle row. The jets from the cooling nozzles 21c, 21c, ... to which the nozzle row belongs are subjected to secondary impact. Therefore, between the interval Pw of the cooling nozzle, the impact width L of the cooling water jet, and the torsion angle β,

L=2Pw/cosβ

The cooling nozzles 21c, 21c, ... are arranged in such a manner that the relationship is established. Here, although it is passed twice, it is not limited to this, and it may comprise three or more times. Further, from the viewpoint of pursuing the uniformity of the cooling ability in the width direction of the steel sheet, the adjacent nozzle rows should be twisted in opposite directions in the direction of the through-plate.

In addition, the arrangement of the cooling nozzles determines the "uniform cooling width" associated with the cooling of the steel sheet. The nature of the nozzle group to be disposed represents the size of the steel sheet in the width direction of the uniformly transported steel sheet. Specifically, in general, the maximum steel sheet width that can be manufactured by the steel plate manufacturing apparatus is uniform. Specifically, for example, it is the size shown in FIG. 5RH.

Here, in the present embodiment, the adjacent nozzle rows as described above are described in the form of twisting the cooling nozzles in opposite directions. However, it is not necessarily limited to this, and it may be a form in which all are twisted in the same direction. Further, the torsion angle (the above β) is not particularly limited, and can be appropriately determined from the viewpoints of necessary cooling ability and equipment arrangement state.

Further, in the present embodiment, from the viewpoint of the above-described advantages, the nozzle rows adjacent to each other in the direction of the through-plate are arranged in a checkerboard arrangement. However, it is not limited thereto, and it may be a form in which the cooling nozzles are juxtaposed in a straight line direction.

The position where the above-described water supply means 21 is provided, in particular, the position where the cooling nozzles 21c, 21c, ... are disposed is not particularly limited. However, after 11 g of the final rolling stand of the hot rolling mill train 11, it is disposed so as to be close to the work roll 11gw of the final rolling stand 11g from the inner side of the casing 11gh of the final rolling stand 11g. In such an arrangement, the steel sheet 1 which has been rolled by the hot rolling mill train 11 can be quenched. Further, the front end portion of the steel sheet 1 can be stably induced to the cooling device 20. In the present embodiment, as can be seen from Fig. 2, the cooling nozzles 21c, 21c, ... close to the work rolls 11gw are arranged close to the steel sheet 1.

Next, basically, the ejection direction of the cooling water sprayed from the cooling water injection ports of the respective cooling nozzles 21c, 21c, ... is a vertical direction. However, the cooling water spray from the cooling nozzles 21c, 21c, ... which are closest to the work rolls 11gw of the final rolling table 11g should be more inclined to the direction of the work rolls 11gw than the vertical. Thereby, the time from the pressing of the steel sheet 1 to the final rolling table 11g until the start of cooling can be further shortened, and the recovery time of the rolling deformation accumulated in the rolling can be made almost zero. Therefore, a steel plate having a finer structure can be manufactured.

The lower water supply means 22, 22, ... are means for supplying cooling water to the lower side of the steel sheet 1. The water supply means 22, 22, ... are provided in the plurality of conduits 22b, 22b disposed in the cooling headers 22a, 22a, ..., and in the respective cooling headers 22a, 22a, ... And ..., cooling nozzles 22c, 22c, ... installed at the tips of the ducts 22b, 22b, .... The water supply means 22, 22, ... are disposed opposite to the above-described upper water supply means 21, 21, ..., and the direction of the cooling water is different, however, substantially the upper and lower water supply means 21, 21, ... The same is omitted here.

Next, the above-described guide portion 30 will be described. Fig. 6 is a conceptual diagram of the upper guide portion 30. Fig. 6(a) is a partial cross-sectional view of the upper guide portion 30 as viewed from above the cooling device 20. Figure 6(b) is a side view. Fig. 6 is a view showing the positions of the cooling nozzles 21c, 21c, ... and the position of the steel sheet 1.

The upper guide portion 30 includes a plate-shaped guide plate 31 and drain passage forming portions 35, 35, ... disposed on the upper surface side of the guide plate 31.

The guide plate 31 is a plate-like member and is provided with inflow holes 32, 32, ..., and outflow holes 33, 33, ....

The inflow holes 32, 32, ... are disposed at positions corresponding to the above-described cooling nozzles 21c, 21c, ..., and their shapes also correspond to the shape of the jet flow. Therefore, the inflow holes 32, 32, ... are arranged side by side in the width direction of the steel sheet to form the inflow hole row 32A, and the inflow hole rows 32A, 32A, ... are arranged in the direction of the through plate. Here, the shape of the inflow hole is not particularly limited, and may be formed so that the jet flow from the cooling nozzle does not hit the guide plate as much as possible. Specifically, it is of course also based on the jet flow characteristics of the cooling nozzles used, however, it should be 10% or more of the amount of cooling water per unit time from one cooling nozzle 21c, and does not hit the guide plate 31 of the upper guide portion 30. And through the shape. Next, from the viewpoint of effectively utilizing the limited space to configure the inflow holes 32, 32, ..., the shape of the opening of the inflow hole should be similar to the shape of the cross section of the cooling water jet (a section perpendicular to the axis of the discharge direction).

On the other hand, the outflow holes 33, 33, ... are rectangular holes which are arranged in parallel in the width direction of the steel sheet to form the outflow hole row 33A. By the remaining portion of the guide plates 31 between the outflow holes 33, 33, ..., the front end of the steel sheet 1 to be conveyed is prevented from projecting into the outflow holes 33, 33, ..., thereby preventing the steel plate intrusion means 33s, 33s, .... The outflow hole rows 33A, 33A, ... are disposed between the inflow hole rows 32A, 32A, ....

that is. The guide plate 31 has the inflow hole row 32A and the outflow hole row 33A staggered along the direction of the through plate.

Here, the good opening shapes of the outflow holes 33, 33, ... are described by the parallel rectangle as described above. Thereby, a large opening area can be efficiently obtained with a limited space. However, it is not limited to this, and it is possible to prevent the steel sheet from being caught as long as the proper displacement is ensured. That is, the shape of the opening of the outflow hole is not limited to the above-described rectangular shape, and may be, for example, a circular shape or a trapezoidal shape. Next, the means for preventing the intrusion of the steel sheet corresponds to the shape of the opening shape. For example, the outflow hole has a trapezoidal shape with an upper bottom and a lower bottom in the direction of the through plate. The means for preventing the intrusion of the steel sheet may also be in the shape of a parallelogram which is inclined from the direction of the sheet.

Fig. 7 is a diagram showing a modification of the outflow hole. In the case of the upper guide portion 30' of the modification of Fig. 7, only the outflow hole 33' is different, and the other portions are the same as the above-described upper guide portion 30. Therefore, the same reference numerals are used for the same portions, and the description thereof is omitted. One of the outflow holes 33' of the upper guide portion 30' has a long hole 33A' in the width direction of the plate, and the mesh member 33B' is attached thereto. It is also possible to form an outflow opening. The so-called mesh fineness of the mesh material 33B' should be a mesh of 5 mm × 5 mm or more from the viewpoint of having little influence on the flow of the cooling water and being less likely to cause foreign matter such as dross to be clogged.

Further, among the edges of the outflow holes 33, 33, ..., the backflow prevention sheets 33p, 33p, ... are vertically provided from the edges perpendicular to the direction of the through-plate direction. The backflow prevention sheets 33p, 33p, ... are arranged to prevent the water entering the outflow holes 33, 33, ... from flowing back to the original position from the outflow holes 33, 33, ... by the purpose. By arranging the backflow prevention sheets 33p, 33p, ..., it is possible to secure more drainage and improve drainage.

In the present embodiment, the backflow prevention sheets 33p, 33p, ... are erected in a substantially parallel manner. However, the backflow prevention sheet may be provided so that the lower end thereof is narrower than the upper end side. Thereby, it is possible to ensure a wide cross-sectional area of the flow path between the backflow prevention sheet and the upright sheets (35a, 35c) of the drain passage forming portion to be described later.

The drain passage forming portions 35, 35, ..., as shown in Fig. 6(b), are members having a concave cross section surrounded by the sheets 35a, 35b, and 35c and extending in the width direction of the steel sheet. The drain passage forming portion 35 is disposed such that the concave opening portion faces the guide plate 31 and covers the upper surface side of the guide plate 31. At this time, the opening portion, that is, the portion between the upper surface of the guide plate 31 and the outflow hole array 33A is covered between the sheet 35a and the sheet 35c. Further, the adjacent drain passage forming portions 35, 35, ... have a specific interval therebetween, and the inflow hole rows 32A, 32A, ..., and the cooling nozzles 21c, 21c, ... are disposed between the intervals.

Further, among the pieces 35b facing the outflow hole row 33A, on the side of the outflow hole row 33A, the commutator piece 36 is disposed directly above the outflow hole row 33A. The shape of the flow regulating piece 36 is such that the drainage of the impact piece 35b is separated into a shape that is rectified toward the bottom surface of the drainage passage in which the backflow prevention sheets 33p and 33p are disposed as described later. For example, inverted triangles, trapezoids, wedges, or other raised shapes can be considered.

Here, the heights of the drain passage forming portions 35, 35, ... are not particularly limited. However, when the inner diameters of the conduits 21b, 21b, ... of the upper water supply means 21 are d, they should be in the range of 5d to 20d. The scope. If the conduits 21b, 21b, ... are larger than 20d, the pressure loss is large and it is not good, and if it is less than 5d, the injection from the cooling nozzle may be unstable.

The upper guide portion 30 as shown above is arranged as shown in Fig. 2 . In the present embodiment, three upper guide portions 30, 30, and 30 are used in parallel in the through-plate direction. Any of the upper guide portions 30, 30, 30 is disposed in a position corresponding to the height direction of the cooling nozzles 21c, 21c, .... That is, in the present embodiment, the upper guide portion 30 closest to the final rolling stand 11g is disposed such that the end portion of the final rolling stand 11g is lower and the other end side is higher. The other two upper guide portions 30 and 30 are disposed at a predetermined interval from the through plate surface and are substantially parallel to the through plate surface.

With such an upper guide portion 30, because of the basic function of the upper guide portion 30, it is possible to solve the problem that the front end portion is caught by the cooling nozzles 21c, 21c, ..., etc. when the front end portion of the steel plate passes.

Next, by the upper guide portion 30, a large amount of cooling water supplied to the upper surface side of the steel sheet can be appropriately discharged. First, after the cooling water supplied from the upper water supply means 21, 21, ... is cooled by the steel sheet, a part of the cooling water flows toward the width direction of the steel sheet and flows downward to discharge the water. However, when the amount of cooling water supplied and the flow density are large, sufficient drainage cannot be performed to form thicker retained water. On the other hand, the upper guide portion 30 maintains the drain water in a thin state by further forming the drain passage. The details are as shown below.

Fig. 8 is an explanatory diagram thereof. In Fig. 8, the symbols are omitted for easy understanding, but the symbols of Fig. 6(b) can be referred to. When the high cooling water flow density and the cooling water supply amount are insufficient for the drainage in the width direction of the steel sheet, the water potential from the cooling nozzles 21c, 21c, ... is also strong. At this time, the cooling water sprayed on the upper surface of the steel sheet 1 moves forward and backward in the direction of the through-plate as indicated by arrows R and R in Fig. 8. When such an impact occurs, the direction of the cooling water changes, and as shown by the arrow S, it moves upward and hits the sheet 35b of the drain passage forming portion 35 through the outflow holes 33, 33, . At this time, as described above, the wedge-shaped commutator piece 36 is disposed on the piece 35b, and the cooling water is converted in the direction indicated by the arrows T and T. At this time, the resistance of the direction conversion can be surely and effectively suppressed to be low by the commutator piece 36.

Thereby, the cooling water reaching the upper side of the guide plate 31 moves in the far/near direction of the plane of Fig. 8 and is drained. At this time, since the backflow prevention sheets 33p and 33p are disposed at the edges of the outflow holes 33, it is possible to suppress the cooling water from flowing back to the outlet holes 33 again.

As described above, by further providing the drainage means, even when a large amount of cooling water having a high water density is supplied to the upper side, the amount of retained water can be suppressed. In addition, since the water supply hole and the discharge hole of the cooling water are divided and the drainage water for the cooling cooling water is used by the structure as described above, the cooling water which starts to move in the middle of the impact is suppressed. Thereby, the water supply and drainage can be smoothly performed, and the thickness of the retained water can be made thinner, thereby improving the cooling efficiency.

By smoothly draining and suppressing the retained water as shown above, the difference in cooling in the width direction of the steel sheet can be suppressed to be small. Thereby, a steel sheet having a uniform quality can be obtained. The difference in cooling should be within ±30 °C.

Here, the outflow holes 33, 33, ... included in one outflow hole row 33A are disposed in the entire width direction of the upper plate portion of the guide portion 30, but are not limited thereto. For example, such an outflow hole may be disposed only in the vicinity of the central portion in the width direction of the steel sheet in which the thickness of the retained water is large.

When the cooling water reaching the upper surface of the guide plate 31 is drained from both ends of the guide plate 31 in the width direction of the steel sheet, a configuration for further improving the drainage property may be added. For example, as shown below.

On the upper side of the guide plate 31, the center of the plate width direction may be formed in a higher manner so as to be inclined toward the both ends in the width direction of the steel sheet. By the height difference, the drainage is easily moved to both ends of the guide plate 31, and the drainage can be more smoothly promoted.

Further, a pump or the like may be provided to perform forced drainage, or a negative pressure may be formed in the drain passage forming portion, and the cooling water may be easily introduced into the drain passage forming portion to further improve the drainage performance.

Further, the upper guide portion itself may be formed to move in the up and down direction, and the upper guide portion 30 may be moved downward in a range that does not affect the through plate to pressurize the stagnant water, forcibly introduce the cooling water. The structure inside the drain passage forming portion.

In addition, the inflow holes 33, 33, ... and the both end portions of the steel plate in the width direction of the guide plate 31 may be chamfered or rounded at the edge portions (edges). Arc processing). Thereby, it is possible to reduce the stuck steel plate and promote the smooth flow of the cooling water.

The material of the guide sheet 31 can be a general material having necessary strength and heat resistance for guiding, and is not particularly limited. However, for the purpose of reducing the scratches on the steel sheet 1 when the steel sheet 1 that has passed through the guide sheet 31 is passed, a material such as a resin which is softer than the steel sheet 1 may be used as the portion having no strength and heat resistance.

Fig. 9 is a view corresponding to Fig. 6(b) among the upper guide portions 130 and 130' of the other embodiment. The 9th (a) is the upper guide 130, and the 9th (b) is the upper guide 130'. Here, members common to the above-described upper guide portion 30 are also denoted by the same reference numerals, and description thereof will be omitted.

In the case of the upper guide portion 130, the drain passage forming portions 135, 135, ... are formed in a form separated from the guide sheets 31. Therefore, when the drain passage forming portions 135, 135, ..., the sheets 35a, 35a, ... and the backflow preventing sheets 33p, 33p, ... are connected by the bottom plates 135d, 135d, ..., the sheet 35c, 35c, ... and the backflow prevention sheets 33p, 33p, ... are connected by the bottom plates 135e, 135e, ... to form the bottom of the drain passage. Such an upper guide portion 130 can also be employed.

The upper guide portion 130' is a form in which the backflow prevention sheets 133p', 133p', ... extend further on the upper surface side of the guide sheet 31.

Fig. 10 is a view corresponding to Fig. 6(b) among the upper guide portions 230, 230' of still another embodiment. The 10th (a) is the upper guide 230, and the 10th (b) is the upper guide 230'. Here, the members that are common to the above-described upper guide portions 30 and 130 are also denoted by the same reference numerals, and the description thereof will be omitted.

In the case of the upper guide portion 230, the drain passage forming portions 235, 235, ... are formed in a form separated from the guide sheets 31. Therefore, when the drain passage forming portions 235, 235, ..., the sheets 35a, 35a, ... and the backflow prevention sheets 233p, 233p, ... are connected by the bottom plates 235d, 235d, ..., the sheet 35c, 35c, ... and the backflow prevention sheets 233p, 233p, ... are connected by the bottom plates 235e, 235e, ..., and the bottom plates 235d, 235d, ..., and the bottom plates 235e, 235e, ... To form the bottom of the drainage path. Further, the backflow prevention sheets 233p, 233p, ... extend further on the upper surface side of the guide sheets 31. The upper guide portion 230 includes the headers 21a, 21a, ... in addition to the cooling nozzles 21c, 21c, ... between the guide plate 31 and the drain passage forming portions 235, 235, ... Catheters 21b, 21b, .... Such an upper guide portion 230 can also be employed.

In the upper guide portion 230', the adjacent drain passage forming portions 235, 235 are used as the one drain passage forming portion 235' in the upper guide portion 230. Thereby, the drainage path indicated by T' in Fig. 10(b) can also be secured. Thereby, the cross-sectional area of the flow path of the drainage path (T') can be increased.

The above description is directed to the upper guide portion of the first example. However, the upper guide portion is not necessarily limited thereto, and the above-described upper guide portion may be used.

Next, the following guide portion 40 will be described. The lower guide portion 40 is a plate-like member that is disposed between the lower water supply means 22 and the steel sheet 1 to be conveyed. Thereby, in particular, when the steel sheet 1 is passed through the manufacturing apparatus 10, it is possible to prevent the front end of the steel sheet 1 from being caught by the lower water supply means 22, 22, ... and the conveyance rollers 12, 12, .... On the other hand, an inflow hole through which the jet flow from the lower water supply means 22 passes is disposed in the lower guide portion 40. Thereby, the jet flow from the lower water supply means 22 can reach the underside of the steel sheet through the lower guide portion 40 to perform moderate cooling.

The shape of the lower guide portion 40 used herein is not particularly limited, and a well-known lower guide portion can be used.

Such a lower guide portion 40 is disposed as shown in Fig. 2 . In the present embodiment, four lower guide portions 40, 40, ... are used to be disposed between the conveyance rollers 12, 12, and 12, respectively. Any of the lower guide portions 40, 40, ... is disposed at a height slightly lower than the upper end portions of the conveyance rollers 12, 12, ..., but not too low.

In the present embodiment, an example in which the lower guide portion is provided will be described. However, the lower guide portion is not necessarily provided.

The rectifying means 50 and 50 are a pair of plate-like members having an arc-shaped cross section shown in Fig. 3(a) and extending in the direction of the plate. Such rectifying means 50, 50 have convex side faces having an arcuate cross section facing upward. That is, the pair of opposing rectifying means 50, 50 are formed such that the interval between the upper end portions thereof is narrow, and at least the interval between the lower end portions is wider than the upper end portion. In the form of Fig. 3(a), the upper end portion is disposed in contact with or close to the upper guide portion 30. On the other hand, the lower end portion thereof is in contact with the housing standing portions 11gr and 11gr.

Further, the arrangement positions of the rectifying means 50 and 50 are as follows. That is, a gap is formed between the housing uprights 11gr, 11gr and the end of the upper guide portion 30 in the width direction of the steel sheet. The rectifying means 50, 50 are disposed at a position corresponding to the vertical direction of the upper guiding portion 30 and the lower guiding portion 40 among the formed gaps. Therefore, it is disposed at a position as shown below, that is, the cooling water supplied to the upper surface of the steel sheet can be rectified when it is divided into the width direction of the steel sheet as shown by arrows D and D in FIG. s position.

When the rectifying means is not provided, the water flowing in the width direction of the steel sheet plate impacts the housing standing portion and moves up and down in the vertical direction. This intense direction change is a factor in flow resistance. In addition, among the water moving up and down respectively, the upward water eventually moves downward due to gravity, and merges with the downward moving water. Therefore, there is also a flow resistance. The above flow resistance is a flow resistance of the entire drainage water of the cooling water, and is one of the causes of hindering smooth drainage. In particular, when the amount of cooling water is increased in order to increase the cooling capacity, this phenomenon is more remarkable, and thus moderate cooling is sometimes obtained. In addition, part of the drainage that hits the side wall and moves upward reaches the upper guide portion, which may form stagnant water, which is one of the causes of the water supply head being cooled by the front end of the cooling nozzle.

On the other hand, by providing the above-described rectifying means 50 and 50, the direction in which the cooling water is directed downward can be smoothly performed and guided to the draining direction. Therefore, even if the amount of cooling water is increased, the flow resistance can be suppressed from becoming large, and the drainage performance can be improved. Secondly, it is possible to maintain a high cooling capacity and to manufacture a steel sheet having excellent mechanical properties.

In the present embodiment, the rectifying means 50 and 50 are described as being circular in cross section. However, the rectifying means 50 and 50 are not necessarily arcuate. As described above, other shapes may be used as long as the direction of drainage can be smoothly converted. For example, it may be a non-arc curve, a slanted line, or a combination of straight lines.

Further, the third (b) diagram is a modification. In the example of Fig. 3(b), the lower ends of the rectifying means 50' and 50' are arranged to have a specific gap between the casing standing portions 11gr and 11gr. By arranging such a gap, the water which is present on the upper surface of the upper guide portion 30 and which should be excluded is directed by the direction of the arrow D', D' by the drainage ejector effect shown by the arrows D, D. Inhale and flow to promote smooth drainage.

As described above, the water existing on the upper surface of the upper guide portion 30, for example, the water flowing through the drain path forming portion 35 of the upper guide portion 30 and the water flowing backward from the inflow hole of the upper guide portion 30.

Returning to Fig. 2, the manufacturing apparatus 10 for hot rolled steel sheets will be described. The rollers 12, 12, ... are the work platforms of the steel sheets 1 and are used to convey the rollers of the steel sheets 1 in the direction of the through sheets. As described above, between the conveyance rollers 12, 12, ..., the lower guide portions 40, 40, ... are disposed.

The nip roller 13 has a water discharge function and is disposed on the lower side of the cooling device 20. Thereby, it is possible to prevent the cooling water sprayed in the cooling device 20 from flowing out to the step side below the steel sheet 1. Next, it is possible to suppress the fluctuation of the steel sheet 1 of the cooling device 20, and in particular, it is possible to improve the plate-passing property of the steel sheet 1 before the front end of the steel sheet 1 is bitten by the winder. Here, the upper side roller 13a among the rollers of the pinch roller 13 can be moved up and down as shown in Fig. 1.

According to the apparatus for manufacturing a hot-rolled steel sheet described above, for example, the production of the steel sheet can be carried out in the following manner. That is, the cooling water spray of the cooling device 20 is stopped from the non-rolling time until the steel sheet is taken up by the coiler until the next steel sheet rolling is started. Next, the step side pinch roller 13 is disposed below the cooling device 20, and the upper roller 13a is moved to a position higher than the upper guide portion 30 of the cooling device 20 during the non-rolling time, and thereafter, the next steel plate roll is started. Rolling.

When the front end of the next steel plate reaches the nip roller 13, the cooling water jet is used for cooling. Further, after the front end of the steel sheet 1 passes through the nip roller 13, the upper roller 13a is lowered, and the nip of the steel sheet 1 is started.

The cooling water injection is started before the front end of the steel sheet 1 is carried into the cooling device 20, and the length of the unstable cooling portion at the front end of the steel sheet can be shortened. Next, by spraying the cooling water, the sheet properties of the steel sheet 1 can be stabilized. That is, when the steel sheet 1 floats up close to the upper guide portion 30, the impact force of the steel sheet 1 from the cooling water jets sprayed from the cooling nozzles 21c, 21c, ... increases, and the direction of the vertical direction of the steel sheet 1 is increased. Lower force. Therefore, even when the steel sheet 1 hits the upper guide portion 30, the impact force received from the cooling water jet can alleviate the impact force, and the frictional heat of the steel sheet 1 and the upper guide portion 30 can be reduced, so that the reduction occurs in Scratch on the surface of the steel plate.

Therefore, the hot-rolled steel sheet is manufactured by the apparatus 10 for manufacturing a hot-rolled steel sheet having the cooling device 20 having such a operation on the lower side of the hot rolling mill row 11, and can be cooled using a high-density, large amount of cooling water. In other words, by manufacturing a hot-rolled steel sheet by such a production method, a hot-rolled steel sheet having a fine structure can be produced.

Further, the plate speed of the hot rolling mill train 11 may be constant in addition to the beginning portion of the through plate. Thereby, a steel sheet having a higher mechanical strength for the entire length of the steel sheet can be produced.

When the cooling water is drained as described above, specifically, the drainage performance can be appropriately determined depending on the necessary heat of cooling of the steel sheet, and is not particularly limited. However, as described above, from the viewpoint of miniaturization of the steel sheet structure, the quenching after the rolling is effective, and therefore, the cooling water having a high flow density should be supplied. Therefore, the drainage can be ensured as long as the drainage performance corresponding to the supply amount and the flow density of the cooling water can be ensured. The flow density of the supplied cooling water may be 10 to 25 m ³ /(m ² ‧ minutes) from the viewpoint of miniaturization of the steel sheet. It can also be a larger flow density.

Fig. 11 is an explanatory view showing a manufacturing apparatus 110 for a hot-rolled steel sheet including the cooling device 120 of the second embodiment, which corresponds to a third view of the manufacturing apparatus 10. When the apparatus 110 for manufacturing a hot-rolled steel sheet is used, the rectifying means 150 of the cooling apparatus 120 is different from the rectifying means 50 of the cooling apparatus 20. The other configuration is shared with the manufacturing apparatus 10, and thus the description thereof is omitted here, and the symbols are also shared.

The rectifying means 150, 150 are injection means for injecting the gas shown in Fig. 11. Such rectifying means 150, 150 have their ejection openings facing downward and disposed between the housing standing portions 11gr, 11gr and the end portions of the upper guiding portions 30.

That is, the flow of the cooling water supplied to the upper surface of the steel sheet is as shown by arrows E and E in Fig. 3, and the gas can be injected from above to perform the subsidized position.

Thereby, it is possible to forcibly move the cooling water downward and guide it to the drainage direction. Therefore, increasing the amount of cooling water can also suppress the increase in flow resistance, and can improve drainage. Secondly, it is possible to maintain a high cooling capacity and to manufacture a steel sheet excellent in mechanical properties.

Here, the embodiment of the rectifying means 150 and 150 is used alone. However, the present invention is not limited thereto, and the rectifying means 50 and 50 of the first embodiment described above may be used in combination. Thereby, the drainage performance can be further improved.

Fig. 12 is an explanatory view showing the manufacturing apparatuses 210 and 210' of the hot-rolled steel sheets including the cooling devices 220 and 220' of the third embodiment, and corresponds to the third drawing of the manufacturing apparatus 10. Fig. 12(a) is a manufacturing apparatus 210, and Fig. 12(b) is a manufacturing apparatus 210'. In the case of the hot-rolled steel sheet manufacturing apparatus 210, 210', the rectifying means 250, 250' of the cooling means 220, 220' are different from the rectifying means 50 of the cooling means 20. The other configuration is shared with the manufacturing apparatus 10, and thus the description thereof is omitted here, and the symbols are also shared.

The rectifying means 250 and 250 are disposed so as to close the upper guide portion 30 and the casing standing portions 11gr and 11gr as shown in Fig. 12(a). On the other hand, the rectifying means 250', 250' are disposed to extend upward from both ends in the width direction of the upper guiding portion 30.

Thereby, the drainage impact housing standing portions 11gr and 11gr indicated by the arrows F, F, F', and F' prevent the stagnation even if a part thereof moves upward and enters the upper surface of the upper guide portion 30.

However, at this time, the drain passage forming portion of the upper guide portion 30 and the drain passage of the cooling water that flows back from the inflow hole to the upper surface of the upper guide portion 30 are secured.

Fig. 13 is an explanatory view of a manufacturing apparatus 310 for a hot-rolled steel sheet including the cooling device 320 of the fourth embodiment, and corresponds to a third diagram of the manufacturing apparatus 10. The remanufacturing means 310 of the hot-rolled steel sheet, which is the rectifying means 350 of the cooling means 320, is different from the rectifying means 50 of the cooling means 20. The other configuration is shared with the manufacturing apparatus 10, and thus the description thereof is omitted here, and the symbols are also shared.

As shown in Fig. 13, the rectifying means 350, 350 are provided with the flow dividing means 360, 360 and the drainage means 370, 370.

The flow dividing means 360, 360 are rectangular members having a wedge-shaped cross section, and have a wedge-shaped cross section as shown in Fig. 13 and extend in the direction of the through plate. The flow dividing means 360, 360 are disposed on the side of the casing standing portions 11gr, 11gr which are impacted when the cooling water supplied to the upper surface of the steel sheet moves in the width direction of the steel sheet.

The drainage means 370, 370 are members arranged such that the longitudinal direction of the tubular member is the direction of the through plate. Further, in a part of the pipe wall, as can be seen from Fig. 13, the openings H and H are disposed. Such drainage means 370, 370 are disposed between the end of the upper guide portion 30 and the housing upright portions 11gr, 11gr.

According to the rectifying means 350, 350, the cooling water supplied to the upper surface of the steel sheet flows toward both sides in the width direction of the steel sheet to be drained. Next, the drainage utilizes the wedge-shaped effect of the flow dividing means 360, 360 to suppress the flow resistance and to flow upward and downward, respectively. The drainage to the lower side is the drainage shown in Fig. 13G and G. On the other hand, the drainage which moves upward by the flow dividing means 360, 360 performs the flow shown in Fig. 13 G' and G', and enters the inside of the pipe from the openings H and H of the drainage means 370, 370. The drainage entering the pipe moves in the length direction of the pipe and is appropriately drained from other parts.

Therefore, the water flowing in the width direction of the steel sheet can suppress the flow resistance by the flow dividing means 360, 360 and move up and down respectively in the vertical direction. Further, among the water moving up and down, the upward water does not return to the lower side due to gravity, but is drained by the drainage means 370, 370 and drained. Therefore, it is possible to prevent the water moving upward from moving again downward to generate flow resistance.

Thereby, the flow resistance at the time of drainage can be suppressed, and the drainage property can be improved. Secondly, it is possible to maintain a high cooling capacity and to manufacture a steel sheet excellent in mechanical properties.

In the above embodiments, the side wall existing on the outer side of the cooling device is described by taking the erecting portion of the final rolling table as an example. However, the side wall is not limited thereto, and may be generated in an arrangement relationship with other devices. The side walls of the other device.

[Examples]

Hereinafter, the present invention will be further described in detail based on examples. However, the invention is not limited to the embodiments.

In the examples, the drainage properties of the examples shown in Figs. 3(a) (No. 1), 12 (a) (No. 2), and 13 (No. 3) were investigated. In addition, the same investigation was conducted for an example (Comparative Example No. 4) in which no rectifying means was provided. Here, the width of the steel sheet of the through-plate having a length equal to the uniform cooling width is 1.6 m, and the distance between the end portion of the uniform cooling width direction of the steel sheet and the housing standing portion is 0.2 m and 0.4 m. Further, the flow density of the cooling water was 20 (m ³ /(m ² ‧ minutes)).

The evaluation of the drainage is judged by whether or not the cooling nozzle is submerged by water, and is "X" when the water is submerged, and "Δ" when the so-called half of the cooling nozzle is not flooded. Also. When a small amount of cooling water was left on the upper guide portion, the cooling nozzle was "○" when it was not flooded, and "◎" was not found when the cooling water was trapped on the upper guide portion. The results are shown in Table 1.

It can be seen from Table 1 that in the comparative example of No. 4, it is evaluated as × or Δ. In particular, when the distance between the end portion of the uniform cooling width direction of the steel sheet and the housing erect portion is 0.2 m, the front end of the cooling nozzle is cooled. Flooded by water. On the other hand, in the example of No. 1 to No. 3, the front end of the cooling nozzle was not flooded, and it was confirmed that the front end of the cooling nozzle can be drained smoothly.

The above is a description of the present invention in a practical manner, but the present invention is not limited to the embodiment shown in the specification of the present patent application, and does not violate the scope of the patent application and the overall specification. The scope of the invention or the scope of the invention to be read may be changed as appropriate, and the cooling device of the hot-rolled steel sheet, the manufacturing apparatus of the hot-rolled steel sheet, and the method of manufacturing the hot-rolled steel sheet, which are produced by the above-described changes, are also included in the present invention. Within the technical scope.

1. . . Steel plate

10, 110, 210, 210', 310. . . Manufacturing device

11. . . Rolling mill column

11g. . . Final rolling table

11gh. . . case

11gr. . . (housing) standing portion (side wall)

12. . . Carrying roller

13. . . Clamping roller

20, 120, 220, 220', 320. . . Cooling device

twenty one. . . Above water supply means

21a. . . Cooling manifold

21b. . . catheter

21c. . . Cooling nozzle

twenty two. . . Water supply means below

22a. . . Cooling manifold

22b. . . catheter

22c. . . Cooling nozzle

30, 30', 130, 130', 230, 230'. . . Upper guide

40. . . Lower guide

50, 150, 250, 250', 350. . . Rectification means

Fig. 1 is a partial schematic view showing a manufacturing apparatus of a hot-rolled steel sheet including a cooling device according to the first embodiment.

Fig. 2 is a partially enlarged view of the cooling device of Fig. 1;

Fig. 3(a) is a perspective sectional view taken along line III-III of Fig. 2(a). Fig. 3(b) is a diagram of a modification.

Fig. 4 is an explanatory view of a cooling nozzle.

Figure 5 is another explanatory view of the cooling nozzle.

Fig. 6 is an explanatory view of the upper guide portion.

Fig. 7 is a view showing another example of the above-described guide portion outflow hole.

Fig. 8 is an explanatory view showing the flow of cooling water of the upper guide portion.

Fig. 9 is a view showing another example of the upper guide portion.

Fig. 10 is a view showing another example of the above-described guide portion.

Fig. 11 is an explanatory view of a cooling device of a second embodiment.

Fig. 12 is an explanatory view of a cooling device of a third embodiment.

Figure 13 is an explanatory view of a cooling device of a fourth embodiment.

11gh. . . case

11gr. . . (housing) standing portion (side wall)

20. . . Cooling device

21a. . . Cooling manifold

21b. . . catheter

21c. . . Cooling nozzle

22a. . . Cooling manifold

22b. . . catheter

22c. . . Cooling nozzle

30. . . Upper guide

40. . . Lower guide

50. . . Rectification means

50’. . . Rectification means

Claims (11)

A steel plate cooling device is disposed on a step side below a final rolling stand of a hot rolling mill train, and includes: a cooling device for a steel plate that is disposed to be a plurality of cooling nozzles for cooling a steel sheet to be conveyed on a conveying roller, and the cooling The nozzle is disposed at a position on the upper surface side and the lower surface side of the steel sheet passing portion to eject the cooling water toward the portion where the steel sheet passes, and has a uniform cooling width wider than the cooling nozzle in a position outside the steel sheet width direction. a rectifying means for rectifying the drainage of the cooling water sprayed by the cooling nozzle, and an upper guiding portion disposed on the upper surface side of the steel plate passing portion, wherein the rectifying means is disposed in comparison with the cooling The uniform cooling width of the nozzle is one of the positions on the outer side in the width direction of the steel sheet and the other side is opposite to the pair of members. The opposite member is disposed such that the upper end is narrowest and the lower end is wider than the upper end. Arranged in contact with or close to the aforementioned upper guiding portion, the lower end is located lower than the upper guiding portion . The cooling device according to claim 1, wherein the rectifying means prevents the cooling water sprayed from the cooling nozzle from reaching the upper surface of the upper guiding portion from the outer side in the width direction of the upper surface guiding portion. The cooling device according to claim 1 or 2, wherein the rectifying means includes a gas ejecting means for injecting gas downward. A steel plate cooling device is disposed on a step side below a final rolling stand of a hot rolling mill train, and includes: a cooling device for a steel plate that is disposed to be a plurality of cooling nozzles for cooling a steel sheet to be conveyed on a conveying roller, and the cooling The nozzle is disposed at a position on the upper surface side and the lower surface side of the steel sheet passing portion to eject the cooling water toward the portion where the steel sheet passes, and has a uniform cooling width wider than the cooling nozzle in a position outside the steel sheet width direction. And a rectifying means for rectifying the drainage of the cooling water sprayed by the cooling nozzle, wherein the rectifying means includes means for diverging the drainage into upper and lower directions, and is capable of being divided A drainage means that leads to the opening of the water above the inflow. A manufacturing apparatus for a hot-rolled steel sheet, comprising: a hot-rolled rolling mill train; and a manufacturing apparatus of a hot-rolled steel sheet according to the cooling device described in the first, second or fourth aspect of the patent application, which is based on the cooling device Further, the side wall is erected at a position on the outer side in the width direction of the steel sheet. The apparatus for manufacturing a hot-rolled steel sheet according to the fifth aspect of the invention, wherein the final rolling stand of the hot rolling mill includes a casing for holding a work roll, and the casing has a portion of the upper guide portion therebetween One of the pair of standing portions, and the standing portion is the aforementioned side wall. A manufacturing apparatus for a hot-rolled steel sheet, comprising: a hot-rolled rolling mill train; and a manufacturing apparatus of a hot-rolled steel sheet according to the cooling device described in claim 1, item 1, or item 4, wherein: A side wall is erected at a position outside the steel plate in the width direction of the cooling device, and at least a part of the rectifying means of the cooling device is disposed to contact the side wall. A manufacturing apparatus for a hot-rolled steel sheet, comprising: a hot-rolled rolling mill train; and a hot-rolled steel sheet manufacturing apparatus according to the cooling device described in claim 1, wherein the cooling is performed The apparatus is provided with a side wall at a position outside the width direction of the steel sheet, and the rectifying means of the cooling device is disposed to have a gap with the side wall. A method for producing a steel sheet, which is obtained by manufacturing a steel sheet by a manufacturing apparatus of a hot-rolled steel sheet according to item 5 of the patent application. A method for producing a steel sheet, wherein the steel sheet is produced by the apparatus for producing a hot-rolled steel sheet according to the fifth aspect of the invention, wherein the steel sheet is produced by: The step of trimming the rolling at the highest pressure rate and the step of cooling by the cooling device described above. A method for producing a steel sheet, which is a method for producing a steel sheet by a manufacturing apparatus for a hot-rolled steel sheet according to the fifth aspect of the invention, wherein the manufacturing apparatus includes a nip roller on a step side of the cooling device, and passes through After the front end of the steel sheet reaches the nip roller, it is cooled by the cooling device.