JPH0575487B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cooling device for steel plates, and in particular, a plurality of low-pressure headers are arranged downstream of a high-pressure spray nozzle along the conveying direction of the steel plate at appropriate intervals in the width direction of the steel plate. A cooling water supply system that can selectively adjust the supply of cooling water to each low-pressure header is connected to these low-pressure headers, and the cooling water supply system allows the cooling water supply system to be positioned outside the steel plate in the width direction according to the width of the steel plate. A steel sheet cooling system that is configured to stop the supply of cooling water to the low-pressure header, thereby eliminating wasted water supply and reducing the amount of cooling water, as well as reducing cooling distortion at the edge of the steel sheet due to uneven cooling speed. Regarding.

FIGS. 1 and 2 show a conventional steel plate water cooling device.
FIG. 2 is a view taken along the - line in FIG. 1.

In Figures 1 and 2, P is a steel plate to be cooled, and in order to convey the steel plate P in the conveying direction d from the left to the right in the figure, a pinch roll is applied from the upstream side to the downstream side. 1. Grooved roll 2.
2. Three groups of flat rolls are provided, and these rolls 1, 2, and 3 horizontally convey the steel plate p while sandwiching it from above and below. Pinch roll 1 and upstream grooved roll 2
A high-pressure No. 1 nozzle 4 is provided between the grooved rolls 2 and 2, and a high-pressure No. 2 nozzle 5 is provided between the grooved roll 2 on the downstream side and the flat roll 3 on the most upstream side. It is being High pressure No. 1 nozzle 4 and high pressure 2
A pair of nozzles 5 and 5 are provided on the top and bottom in order to cool the steel plate p from its upper and lower surfaces. Further, the high-pressure nozzles 4 and 2 are arranged along the width direction of the steel plate p perpendicularly to the conveyance direction d, and the cooling water is injected at the tips thereof at an acute angle with the conveyance direction d. A slit for this purpose is formed along the width direction of the steel plate p. The grooved roll 2 prevents the backflow of cooling water that is injected from the high-pressure No. 1 nozzle 4 and the high-pressure No. 2 nozzle 5 and flows in the conveying direction d along the steel plate p. In addition, 6 is a high-pressure No. 2 header that branches and supplies high-pressure cooling water to the high-pressure No. 2 nozzles 5, 5.
7 is a high-pressure water distributor that distributes and supplies high-pressure cooling water from a high-pressure supply source to the high-pressure No. 2 header 6 and the high-pressure No. 1 nozzle 4.

In addition, a low pressure header 8 is installed between the flat rolls 3 and 3.
are provided, one pair each on the upper and lower sides. The low-pressure header 8 is arranged along the width direction of the steel plate p similarly to the high-pressure No. 1 and No. 2 nozzles 4 and 5, and nozzle holes are formed on the lower surface of the low-pressure header 8 at appropriate intervals. A low-pressure main header 9 is arranged along the conveying direction d to branch-supply low-pressure cooling water to each low-pressure header 8, and the low-pressure main headers 9, 9
A low-pressure water distributor 10 is provided for distributing and supplying low-pressure cooling water from a low-pressure supply source. In addition, 11 is a flow control valve, 12 is an orifice, and 13 is a telescopic tube.

The steel plate p is conveyed by a pinch roll 1, a grooved roll 2, and a flat roll 3, and is passed through a high pressure No. 1 nozzle 4,
Cooling treatment is performed with cooling water injected from the high-pressure No. 2 nozzle 5 and the low-pressure header 8. To explain water quenching, which is a typical example of water cooling treatment of the steel plate p, the steel plate p is carried into a water cooling device at about 900° C., and cooling is started with cooling water from the high-pressure No. 1 nozzle 4.
At this time, water vapor is generated from the surface of the steel plate P, and a film of water vapor covers the surface of the steel plate P and obstructs cooling, so high-pressure water is injected to break through this water vapor film and apply cooling water to the steel plate P. Since the steel plate p is conveyed continuously, not only the high pressure nozzle 4 but also the high pressure 2
No. 5 nozzle provides additional cooling. When the surface of the steel plate P is cooled to about 600℃ or less, the generation of water vapor film becomes inactive, and it can be sufficiently cooled with low pressure cooling water. Cooled by low pressure cooling water.

By the way, in the conventional water cooling device described above, the high pressure No. 1 nozzle 4, the high pressure No. 2 nozzle 5, and the low pressure header 8 are all arranged in the width direction of the steel plate p, and their length in the steel plate width direction is is set to the maximum width of the steel plate processed by the equipment. Then, regardless of the plate width B of the steel plate p being conveyed, the total length A
Spraying more cooling water. For this reason, the cooling water was sprayed even in areas where the steel plate P was not present and cooling was not necessary, resulting in wasted cooling water and was uneconomical. Furthermore, cooling water is sprayed onto the edges of the steel plate P not only from the top and bottom but also from the sides, resulting in three-sided cooling, so the cooling rate is higher at the edges than at the center of the steel plate P, resulting in uneven cooling and This was the cause of cooling distortion of p. Therefore, in the past, the spray nozzles arranged in the width direction of the steel plate were divided into blocks at appropriate intervals along the width direction of the steel plate, and the water supply to each block was controlled according to the width of the steel plate. There are some devices that do this, but the structure becomes complicated and expensive.

The present invention has been devised to effectively solve the above-mentioned conventional problems, and an object of the present invention is to easily adjust the width of the hydraulic cooling zone to be wide or narrow according to the width of the steel plate, and to improve cooling. It is an object of the present invention to provide a cooling device for a steel plate that can reduce the amount of water and reduce the cooling distortion of the edge of the steel plate due to non-uniform cooling rate.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In explaining the cooling device of this embodiment, the differences from the conventional water cooling device shown in FIGS. 1 and 2 will be mainly described.

In FIGS. 3 and 4, the conveying means consisting of the pinch roll 1, the grooved roll 2, the flat roll 3, etc. for conveying the steel plate p is the same as that of the water cooling device described above, and the high pressure No. 1 nozzle 4, the high pressure No. 2 No. nozzle 5,
5, a high-pressure water supply system consisting of a high-pressure No. 2 header 6 for supplying high-pressure water to these, a high-pressure water distributor 7, etc., also have substantially the same configuration. However, in this embodiment, the high-pressure No. 1 nozzle 4 and the high-pressure No. 2 nozzles 5, 5 are provided with a spray width adjustment rod 14 that can variably adjust the spray width of the cooling water in the width direction of the steel plate p. This will be explained for the high pressure No. 1 nozzle 4 with reference to FIGS. 7 and 8. The high-pressure No. 1 nozzle 4 is a so-called slit nozzle, and a slit 15 with a gap of several mm is formed at the tip of the nozzle 4 so as to open continuously along the width direction of the steel plate p. A groove or a through hole 16 is formed at the entrance of the slit 15 so that the spray width adjustment rod 14 can be slid by pushing or pulling it from the outside of the nozzle 4, and the entrance of the slit 15 is blocked by the spray width adjustment rod 14. The opening width of the slit 15 can be adjusted.

On the other hand, a low water pressure cooling zone is formed on the downstream side of the high pressure No. 2 nozzle 5 in the conveying direction d, and 2/3 of the total low pressure headers provided in this low water pressure cooling zone are low pressure headers 8.
are arranged at appropriate intervals in the steel plate width direction along the steel plate conveyance direction, and the remaining 1/3 of the low pressure headers 8a are arranged at appropriate intervals in the steel plate conveyance direction along the steel plate width direction. has been done. Low pressure header 8
are provided on the upper and lower sides of a pair of upper and lower flat rolls 3, respectively, so as to sandwich the steel plate p. Low-pressure nozzles 17 are attached to each low-pressure header 8 at predetermined intervals in its longitudinal direction, that is, in the conveyance direction d. The low pressure nozzle 17 extends from the low pressure header 8 to between the flat rolls 3, 3. In addition, in order to branch and supply low-pressure cooling water to each low-pressure header 8, a low-pressure main header 9 is arranged in the width direction of the steel plate, and
A shutoff valve 18 for controlling water supply to the low pressure header 8 on and off is provided in a pipe line that communicates the low pressure main header 9 with each low pressure header 8 .

Next, the operation of this embodiment will be described.

Since the plate width B of the steel plate p is known in advance, the spray width adjustment rod 14 is slid along the through hole 16 so that the spray width of the high pressure No. 1 nozzle 4 and the high pressure No. 2 nozzles 5, 5 becomes approximately B. I'll keep it. Therefore, as shown in FIG. 5, high-pressure cooling water is injected from these nozzles 4 and 5 onto both upper and lower surfaces of the steel plate P carried into the cooling device over the width B of the steel plate. The reason why the high-pressure No. 1 nozzle 4 is arranged in the width direction of the steel plate p is to align the so-called cooling start lines so that the steel plate p is cooled in the width direction under the same conditions.

After the steel plate p is cooled in the high water pressure cooling zone, it is conveyed to the low water pressure cooling zone formed by the cooling water injected from the downstream low pressure nozzle 18 group, but the width of the low water pressure cooling zone is also the same as that of the steel plate p. Approximately match the board width B. That is, in order to stop the water supply to the low-pressure header 8 located on the outside in the width direction of the steel plate p, the shutoff valve 18 provided in the conduit connecting the low-pressure main header 9 and the low-pressure header 8 is closed. Then, as shown in FIG. 6, cooling water is sprayed from the low-pressure nozzle group 17 onto both the upper and lower surfaces of the steel plate p by approximately the width of the plate.

In this way, in this embodiment, the widths of the high water pressure cooling zone and the low water pressure cooling zone can be freely adjusted to match the sheet width B according to the sheet width B of the steel sheet p to be cooled. Cooling water is no longer sprayed on the air, reducing the amount of cooling water required.
Furthermore, the amount of cooling water sprayed on the edge of the steel plate p approaches the amount of sprayed water on the center, which alleviates the difference in cooling speed between the edge and the center of the steel plate p.
edge cooling distortion can be reduced. Also, low pressure header 8
are provided along the conveyance direction d, and a plurality of them are arranged in parallel in the width direction, so the width adjustment of the low water pressure cooling zone is as follows:
This can be easily carried out by opening and closing the shutoff valve 18, and since the low pressure header 8 is not divided into parts and has a simple structure, it can be provided at low cost. In addition, the high pressure No. 1 and No. 2 nozzles 4 and 5 are controlled by the spray width adjustment rod 14.
The spray width can be easily and reliably adjusted.

In addition, in the above embodiment, the high pressure No. 1 nozzle 4 and the high pressure No. 2 nozzle 5 were used as the high pressure spray nozzles, but the high pressure No. 2 nozzle 5 is an auxiliary nozzle, so it is not necessarily necessary and may be omitted. ,
Moreover, even when it is installed, it may be installed along the conveyance direction d instead of the width direction of the steel plate p. Furthermore, if all the low pressure headers in the low water pressure cooling zone are arranged along the width direction of the steel sheet, water cannot be saved and the steel sheet will be cooled unevenly. On the other hand, if all the low-pressure headers are arranged along the steel plate conveying direction, it is not possible to drain water well from the steel plate p.

In the present invention, two-thirds of the low pressure headers 8 of all the low pressure headers in the low water pressure cooling zone are connected to a shutoff valve 1 for each header.
8 along the steel plate conveyance direction, and the remaining low pressure header 8a is disposed along the steel plate width direction, so water saving and The balance between uniform cooling and draining by the low-pressure header 8a along the width direction of the steel plate can be set to an optimal state. Furthermore, the method of adjusting the spray width of the high-pressure spray nozzle is not limited to the above-mentioned embodiment, and the spray nozzle may be divided into a plurality of parts in the board width direction, and the water supply to each divided spray nozzle may be appropriately restricted. .

As is clear from the above description, according to the present invention, two-thirds of the low pressure headers of the low pressure cooling zone are arranged along the steel sheet conveying direction via a cutoff valve for each header, and , the remaining low-pressure headers are arranged along the width direction of the steel plate, so the low-pressure header with a shutoff valve installed in the steel plate conveying direction saves water and equalizes cooling, and the low-pressure header along the width direction of the steel plate can drain water. You can set the balance to the optimal state.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing a conventional water cooling device, FIG. 2 is a view taken along the - line in FIG. 1, FIG. 3 is a side sectional view showing an embodiment of the device according to the present invention, and FIG. The figure is a - line arrow view of Fig. 3, and Fig. 5 is a - line view of Fig. 3.
Fig. 6 is a view taken from the − line in Fig. 3;
Figure 7 is an enlarged sectional view of Figure 3, and Figure 8 is an enlarged cross-sectional view of Figure 7.
It is a cross-sectional view taken along the line - in the figure. In the figure, 1 is a pinch roll, 2 is a grooved roll, and 3
is a flat roll, 4 is a high pressure No. 1 nozzle, 5 is a high pressure No. 2 nozzle, 8 is a low pressure header, 9 is a low pressure main header, 14 is a spray width adjustment rod, 15 is a slit,
16 is a through hole, 17 is a low pressure nozzle, 18 is a shutoff valve,
p is the steel plate, d is the conveyance direction, and B is the plate width.

Claims (1)

[Claims] 1 A high-pressure cooling zone is provided with high-pressure spray nozzles above and below to inject cooling water onto the steel plate while it is being conveyed, and a plurality of spray nozzles are installed above and below in a low-water pressure cooling zone formed downstream of the high-water pressure cooling zone. In a cooling system having low pressure headers, 2/3 of all the low pressure headers in the low water pressure cooling zone are arranged along the steel plate conveying direction at appropriate intervals in the steel plate width direction, and the remaining low pressure headers are arranged at appropriate intervals in the steel plate width direction. The steel plate is arranged along the width direction of the steel plate at appropriate intervals in the steel plate conveying direction, and is arranged between the low pressure header along the steel plate conveying direction and the cooling water supply system to supply cooling water to each low pressure header. A cooling device for steel plates, characterized in that a shutoff valve is provided for selective adjustment according to the width.