JPH11244926A - Device for cooling hot rolled steel sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To interrupt cooling water supplied to the edge parts of a hot rolled steel sheet from the underside by connecting a shielding part for interrupting the cooling water which is jetted from nozzles to an arm and shifting the shielding part to a position where the cooling water is interrupted and a position where the cooling water is not interrupted by operating the arm. SOLUTION: A cooling system is arranged along the direction of the roll axis between rollers 1. The nozzles 5 of the cooling system are provided extending between the rollers 1 and colling is executed by jetting the cooling water which is supplied from a main pipes 3 and headers 4 to a hot strip 10. The shielding part 9 provided at the tip of the arm 8 is moved through an operating plate (operating member) 6 and the arm 8 with an air cylinder (operating device) 7. When the arm 8 is rotated anticlockwise, the cooling water which is jetted from the nozzles 5 is interrupted with the shielding part. It is desirable to use a roller table on which disk-like rollers are attached at fixed intervals and adjacent rollers are alternately arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a cooling device for cooling a hot-rolled steel sheet from below.

[0002]

2. Description of the Related Art As an example of a hot-rolled steel sheet, a hot strip by continuous hot rolling will be described as an example. In a rolling line, a slab is usually charged into a heating furnace, heated to a predetermined temperature, and then extracted. After being rolled to a predetermined size through finish rolling, it is cooled to a predetermined temperature by water cooling from above and below with a roller table called a run-out table, and then wound into a coil by a winder.

[0003] Water cooling in the roller table is performed by a cooling device comprising a header arranged above and below the roller table along the roll axis direction and a number of nozzles attached to the header at regular intervals. Because the temperature of the edge of the previous hot strip is usually low, if the edge is cooled with water in the same way as other parts, it will be overcooled and cause cracks, which may impair product quality. become.

As a countermeasure to this problem, a method of providing a valve in the nozzle and switching off the valve of the nozzle for cooling the edge portion to stop the water injection from the valve can be considered. In this case, the ejection amount from the other nozzles becomes unnecessarily large, resulting in supercooling. There has also been proposed a method of cutting off the cooling water supplied to the edge portion without increasing the supply of the cooling water to the portion other than the edge.

Japanese Utility Model Publication No. Sho 62-35524 discloses a method in which cooling water supplied to an edge portion is cut off by a bucket arranged so as to be able to advance and retreat in the width direction of the plate.
No. 9 discloses a method in which V-shaped and inverted V-shaped drain gutters are disposed so as to be able to advance and retreat in the traveling direction of a hot strip, and the cooling water supplied to an edge portion and / or a center portion is shut off.

[0006]

Any of the above-mentioned methods of shutting off the cooling water supplied to the edge portion cuts off the cooling water supplied to the upper side of the hot-rolled steel sheet, and the cooling water supplied to the upper side. It is not sufficient just to be able to shut off the airflow, and the cooling water supplied from below will overcool the edges, which may cause cracks and cause unevenness of the material in the width direction of the plate. In particular, such a problem easily occurs in a thin material having a high cooling effect.

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problem and to cut off cooling water supplied from below to an edge portion. However, the present invention is provided to cool a hot-rolled steel sheet from below. Since the nozzles protrude upward from the header and extend between the rolls, the above-described known method cannot be used as it is from the viewpoint of space and configuration.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a cooling device that can shut off cooling water supplied from below to an edge portion.

[0009]

A cooling device according to the present invention includes a header disposed under a roller table along a roll axis direction, a nozzle projecting upward from the header and extending between the rolls, and a nozzle extending upward between the rolls. An arm having a shielding portion projecting laterally at the upper end for blocking the cooling water injected from the nozzle, and a position where the shielding portion is located above the nozzle to block the cooling water, which is connected to the arm below the roller table. And an operating device that operates the arm so as to be able to switch to a position where the arm is retracted from the position and does not hinder the supply of the cooling water to the hot-rolled steel sheet.

The operating device of the present invention may be provided individually for each arm or one for a plurality of arms.
Each arm is controlled by one actuator. If an actuating device is provided for each arm and the shielding part can be individually controlled as in the former case, finer cooling control of the edge part becomes possible, and the material in the width direction of the steel sheet can be made uniform. . On the other hand, the latter device, in which a plurality of arms are controlled by one operating device, has a simple structure and does not take up space, and is suitable for installation in a narrow space below the roller table. In a more preferable aspect of the latter operating device, the operating device is arranged along the traveling direction of the hot-rolled steel sheet under the roller table, and an operating member that connects each arm and is capable of moving forward and backward, and an operating device that moves the operating member forward and backward. It is composed of In any case, the operating device may be any device or mechanism capable of operating the arm so that the shielding portion can be switched between a position where the cooling water is shut off and a position where the supply of the cooling water is not obstructed. Although it does not matter, an air cylinder, a pinion rack mechanism, or the like, or a device including these and an operation member may be exemplified. The arm in the present invention may have a lower end fixed to the actuator, but preferably has a lower end pivotally attached to the actuator and an intermediate portion pivotally attached to a pivot, more preferably a nozzle, disposed between the rolls. The preferred reason is as follows.

The interval between the rolls is the narrowest between the axes of the rolls. The closer the axis fulcrum of the arm is to the line connecting the axis of the roll, the smaller the amount of movement of the arm between the axis of the roll. Position, in other words, the roll pitch can be narrowed, and in the case of a thin plate, the tip hangs down and easily hits the roll at the time of conveyance.However, by reducing the pitch between rolls, even a thin steel plate can hit the roll. It can be transported without being hung, and thin steel plates can be rolled. The arm has an advantage that the supporting state and the movement are stabilized by axially attaching the intermediate portion, and axially attaching the lower end to the operation member and supporting the arm at two points.

Further, the arm is supported on the nozzle so that the structure is relatively simple and the space can be saved. Roller tables include a type in which rolls of a fixed length are arranged side by side, and a type in which disk-shaped rolls are attached at regular intervals and adjacent rolls are alternately arranged. According to the latter roller table in which the disk-shaped rolls are alternately arranged, the pitch between the rolls can be reduced, and the thin plate can be transported. The cooling device of the present invention can also be applied to a roller table in which such disk-shaped rolls are alternately arranged to reduce the pitch between the rolls. The cooling device of the present invention is preferably used in combination with a cooling device having a known shut-off device for cooling the hot-rolled steel sheet from the upper side and shutting off cooling water to the edge portion, whereby the edge portion particularly easily generated in a thin plate is used. It is possible to prevent overcooling and prevent cracks at the edge portion. Therefore, it is possible to manufacture thin steel plates by hot rolling, which was difficult in the past.
The process can be saved by the cold rolling and annealing work performed in the next process, and the energy can be saved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a roller table in which rolls 1 of a fixed length are arranged side by side, and a cooling device 2 for supplying cooling water to a hot strip from below is arranged between the rolls 1. 2 shows the overall configuration of the cooling device 2. The cooling device 2 is arranged along the roll axis direction between the rolls, and a header 4 to which cooling water is supplied from a main pipe 3.
And a nozzle 5 projecting upward from the header 4 at regular intervals and extending between the rolls, and an operation member disposed at both edge portions so as to be movable in a direction perpendicular to the roll axis (the traveling direction of the hot strip). Operating plate 6 and an air cylinder 7 as an operating device for moving the operating plate 6 forward and backward
An arm 8 having an intermediate portion pivotally attached to the nozzle 5, a lower end pivotally attached to the operation plate 6, and an upper portion curved in an arc shape, and a shielding portion 9 projecting laterally from the arm tip. When the cooling water is sprayed onto the hot strip 10 from the nozzle 5 at the position of the solid line 9 shown in FIG. 3 and the operating plate 6 is moved by a predetermined amount in the direction of the dashed line in FIG. Numeral 8 rotates counterclockwise in the drawing to the position indicated by the alternate long and short dash line, and the shielding portion 9 blocks the cooling water jetted from the nozzle 5. In FIG. 1, reference numeral 11 denotes a motor for driving the roll 1 to rotate.

Although not shown in FIG. 2, a cooling device is provided on the roller table for cooling the hot strip from above with cooling water jetted from nozzles, and the cooling device is provided with cooling water supplied to an edge portion. Has a known shut-off device capable of shutting off. According to this device, of the cooling water for cooling the hot strip from above and below, the cooling water for cooling the edge portion can be shut off both at the top and bottom, so that excessive cooling of the edge portion, which is particularly likely to occur on a thin plate, is prevented, and cracks at the edge portion are prevented. Can be prevented. Therefore, as described above, it is possible to manufacture a thin plate by hot rolling, and it is possible to save steps and energy in a subsequent cold rolling operation and an annealing operation.

FIG. 4 shows a roller table in which disk rolls 13 mounted at regular intervals are arranged alternately, roll drive motors 14 are provided alternately left and right, and a cooling device 15 is arranged between the disk rolls. As shown in FIG. 5, the cooling device 15 projects from the header 16 and extends between the disk roll 13 and the roll shaft 18 as shown in FIG.
When the arm 22 for moving the operation plate 23 is rotated, the arm 22 is provided with a shielding part 21. When the arm 22 is turned, the cooling water ejected from the nozzle 19 is shut off and the cooling water is sprayed on the hot strip 10. It can be switched.

According to the present apparatus, the present invention can be applied to a roller table having a narrow roll pitch in which disk rolls are alternately arranged as described above. In this device,
Like the previously described device, it has a cooling device with a known shut-off device that cools the hot strip from above and shuts off the cooling water to the edge.

[0017]

According to the first aspect of the present invention, the cooling water can be cut off by being applied to the edge portion of the hot-rolled steel sheet from below from the nozzle projecting upward from the header and extending between the rolls, thereby cutting off the cooling water. If it is used together with a device that shuts off the supply of cooling water that cools the edge from above, the overcooling of the edge is prevented,
It is also possible to roll thin steel sheets, which could not be rolled due to cracks caused by supercooling in the past.Thinning in the hot rolling step enables thinning of the next process and energy saving, and also the width direction of the steel sheet Can be made uniform.

According to the second aspect of the present invention, the arm can be rotated even in a narrow space between the rolls to switch the shielding portion between the blocking position and the retracted position, in other words, the roller having a narrow pitch between the rolls. The present invention can be applied to a table, and even a thin steel plate can be transported and rolled. In addition, since the arm is supported at two points, the supporting state and movement are stable.

According to the third aspect of the present invention, the structure is simple, takes up little space, and is applicable to a roller table having a narrow pitch between rolls. According to the fourth aspect of the present invention, the structure of the actuator for operating the arm is simple, does not take up space, and is suitable for installation in a narrow space below the roller table. According to the fifth aspect of the present invention, by alternately arranging the disk rollers, the present invention can be applied to a roller table in which the pitch between rolls can be narrowed, and thinner materials can be conveyed and rolled.

[Brief description of the drawings]

FIG. 1 is a plan view of a roller table including a cooling device according to the present invention.

FIG. 2 is a front view of the cooling device shown in FIG.

FIG. 3 is an enlarged view of a cooling device.

FIG. 4 is a plan view showing another embodiment of the roller table provided with the cooling device according to the present invention.

FIG. 5 is a front view of the cooling device shown in FIG. 4;

[Explanation of symbols]

 1. Roll 2. Cooling device 3. Main pipe 4, 16. Header 5, 19. Nozzle 6, 23 .. Operation plate (operation member) 7. Air cylinder (operation device) 8, 22.・ Arm 9,21 ・ ・ Shielding part 11,14 ・ ・ Motor 13 ・ ・ Disk roll 15 ・ ・ Cooling device 18 ・ ・ Roll shaft

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C21D 9/573 101 C21D 9/573 101Z (72) Inventor Masafumi Odachi 1-3-16 Nakadori, Kure City, Hiroshima Pref. Machine Co., Ltd.

Claims (5)

[Claims] 1. A header disposed under a roller table along a roll axis direction, a nozzle projecting upward from the header and extending between the rolls, and a nozzle extending upward between the rolls and being ejected from the nozzle to the upper end. An arm having a shielding part that protrudes laterally to block cooling water, and an arm that is connected to the arm below the roller table, where the shielding part is located above the nozzle to block cooling water, and is retracted from the position. A cooling device for a hot-rolled steel sheet, comprising: an operating device for operating an arm so as to be able to switch to a position that does not hinder the supply of cooling water to the hot-rolled steel sheet. 2. The cooling device for a hot-rolled steel sheet according to claim 1, wherein the arm is supported by a pivot disposed between the rolls. 3. The cooling device for a hot-rolled steel sheet according to claim 1, wherein the arm is pivotally supported by the nozzle. 4. The operating device is disposed below the roller table along the traveling direction of the hot-rolled steel sheet, and comprises an operating member which connects each arm and which can move forward and backward, and an operating device which moves the operating member forward and backward. The cooling device for a hot-rolled steel sheet according to any one of claims 1 to 3. 5. The hot-rolled steel sheet according to claim 1, wherein the roller table is a roller table in which disk-shaped rolls are attached at regular intervals and adjacent rolls are arranged alternately. Cooling system.