JPH09206819A - Cooling device for the bottom surface of hot-rolled steel strip - Google Patents

Abstract

(57) Abstract: When cooling a hot rolled steel strip on a hot run table, the device of the present invention prevents the tip of the steel strip from penetrating between the rollers of the hot run table, and cools it by changing the cooling zone. Provided is a cooling device which prevents heat deterioration of a steel strip guide body due to a traveling steel strip when the steel strip is stopped. SOLUTION: A hot strip table 2 of a hot rolling facility is provided with a steel strip guide body 6 immediately below a running position of a steel strip in a widthwise central portion between the rollers 1, and a guide body cooling water supply port 9 is attached to the steel strip guide body 6. In addition, the full-cone nozzle 7 is arranged below the running steel strip 3 between the rollers 1 at both ends of the steel strip guide body 6 to cool the lower surface of the hot-rolled steel strip.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a cooling device for a lower surface of a hot-rolled steel strip.

[0002]

2. Description of the Related Art In hot rolling of a steel strip, as shown in FIG. 4, after finishing rolling, a steel strip 3 runs on a hot run table 2 in which rollers 1 are arranged at equal intervals up to a winding device ( While moving, the cooling water is made to flow down from the upper surface of the steel strip to the upper surface of the steel strip 3 by the laminar flow nozzle 4, and the cooling water is jetted to the lower surface of the steel strip 3 from the nozzles 5 arranged between the rollers 1, The band 3 is cooled to the set winding temperature. In such cooling of the steel strip 3, the cooling water supplied from the upper surface of the steel strip flows on the upper surface of the steel strip from both ends in the flow width direction, so that the cooling water stays on the upper surface of the steel strip. Since the cooling water supplied to the lower surface of the steel strip 3 collides with the steel strip 3 and drops at the same time, the lower surface is cooled for a shorter time than the upper surface of the steel strip 3 and the cooling is uneven on the upper and lower surfaces of the steel strip 3. . In order to solve this difficulty, a full cone type nozzle is arranged on the lower surface of the steel strip 3 to inject the cooling water into the steel strip 3 in an inverted conical shape to expand the contact area of the cooling water and make the upper and lower surfaces of the steel strip 3 uniform. Cooling is disclosed in Japanese Utility Model Publication No. 4-80604.

[0003]

As described above, in the hot run table 2 in which the full cone type nozzle is arranged and the lower surface of the steel strip 3 is cooled, the steel strip 3 after finish rolling is thin with a thickness of about 2.0 mm or less. Then, the tip of the running steel strip 3 bends downward, and the steel strip 3 enters the space between the rollers 1 of the hot run table 2 and the succeeding steel strip jumps out of the hot run table 2 due to inertia. There is a problem that it will be stopped. The device of the present invention has been made in order to advantageously solve such a problem, a steel strip guide body is provided between the rollers of the hot run table to prevent the steel strip tip from plunging, and a more uniform running steel strip is provided. When cooling is required, the steel strip is uniformly cooled by supplying cooling water from the steel strip guide body. Furthermore, when the injection of cooling water from the bottom surface of the steel strip in the cooling stop zone is stopped by changing the cooling zone of the hot run table, etc., heating deterioration of the steel strip guide body due to the traveling steel strip (deformation etc.)
It is an object of the present invention to provide a cooling device for a lower surface of a hot-rolled steel strip, which prevents the above-mentioned problems and solves the above problems and has the excellent functions as described above.

[0004]

A feature of the apparatus of the present invention is that a steel strip guide body is provided immediately below a steel strip traveling position in a widthwise central portion between hot run table rollers of hot rolling equipment. A cooling device for the lower surface of a hot-rolled steel strip, characterized in that a guide body cooling water supply port is attached to the body, and a full-cone type nozzle is arranged at the lower part of the traveling steel strip between the rollers at both ends of the steel strip guide body.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, a steel strip guide body 6 is provided just below a running position of a steel strip (not shown) in a widthwise central portion between rollers (not shown) of a hot run table 2. A full cone type nozzle 7 is disposed below the running steel strip between the rollers at both ends of the body 6, and cooling water 8 is jetted to the lower surface of the steel strip 3 in an inverted cone shape, and the upper surface of the steel strip 3 is laminar flow nozzle as described above. Cooling water is made to flow from 4 to cool. When such a steel strip guide body 6 is made of, for example, heat-resistant resin, rubber or the like, it is possible to prevent the occurrence of scratches or the like on the steel strip due to the contact of the leading end of the traveling steel strip.

Cooling of the steel strip on the hot run table 2
Depending on the steel type of the steel strip, a part of the cooling zone may be a cooling stop zone, and the cooling stop zone may be changed. In such a case, the flow and injection of the cooling water from the upper and lower surfaces of the steel strip in the cooling stop zone are stopped, and when the cooling water injection from the full cone type nozzle 7 on the lower surface of the steel strip is stopped, the steel strip guide body is stopped. No. 6 cannot be cooled by the cooling water 8 and is heated and deteriorated by the traveling steel strip. In order to prevent such deterioration of the steel strip guide body 6, a guide body cooling water supply port is attached to the steel strip guide body 6, and cooling water is supplied to the upper surface of the steel strip guide body 6 to cool it. The durability of the steel strip guide body 6 can be improved.

When such a steel strip guide body 6 is arranged in the widthwise central portion between the rollers, the amount of jetted water from the full cone type nozzle 7 to the jetted cooling water 8 is somewhat blocked, and cooling is performed more than other parts. It becomes slightly uneven. This non-uniform cooling may not be preferable depending on the steel type. Therefore, in a line for rolling such a steel type, the steel strip guide body 6 may also inject cooling water to uniformly cool the steel strip. It is preferable to attach a steel strip cooling water supply port to the guide body 6.

[0008]

Next, an embodiment of the present invention will be described. 2 and 3, a steel strip guide body 6 is arranged immediately below the traveling position of the steel strip 3 at the center in the width direction between the rollers of the hot run table 2, and the guide body cooling water is provided on the upper surface of the steel strip 3 guide body 6. A supply port 9 is attached, and a steel strip cooling water supply port 9 is attached if necessary. A full cone type nozzle 7 is arranged below the running steel strip at both ends of the steel strip guide body 6 to configure a cooling device for the lower surface of the hot rolled steel strip, and the cooling device is provided between the rollers 1 of the hot run table 2. Along with the arrangement, a laminar flow type nozzle (not shown) that is usually used is arranged on the upper surface of the traveling steel strip 3.

Therefore, when the front end of the steel strip 3 that has been hot-rolled (finish rolling) travels between the rollers 1, the steel strip guide body 6 prevents the steel strip guide body 6 from bending downward and entering between the rollers 1. It guides the vehicle so that it travels on the roller 1 (on the hot run table 2).

During cooling of the steel strip 3, the cooling zone of the hot run table 2 may be divided according to the type of steel and divided into a cooling stop zone and a cooling zone, and the cooling zone may be changed. Therefore, in the cooling stop zone, the injection of the cooling water to the traveling steel strip 3 is stopped, and the injection of the cooling water from the full cone type nozzle 7 on the lower surface of the traveling steel strip 3 is also stopped. Since the steel strip guide body 6 is deteriorated by heating due to the steel strip 3 traveling immediately above 6,
From the cooling water supply pipe 12 of the steel strip guide body 6 to the steel strip guide body 6
The cooling water is supplied to the guide body cooling water supply port 9 attached to the upper surface of the steel strip so that the steel strip 3 does not come in contact with the upper surface of the steel strip guide body 6 to wet the steel strip steel strip guide body 6. Is to prevent.

If it is necessary to more uniformly cool the width of the steel strip depending on the type of the steel strip 3, the header 1
From the steel strip cooling water supply port 10 to the bottom surface of the steel strip 3 to inject the cooling water, and from the full cone type nozzle 7 disposed below the running position of the steel strip 3 between the rollers 1 at both ends of the steel strip guide body 6. Of the cooling water 8 for cooling the steel strip 3 uniformly. In the case of a steel strip that does not require such uniform cooling, cooling from the steel strip cooling water supply port 10 of the steel strip guide body 6 is performed. The water jet is stopped, and the steel strip 3 which is slightly unevenly cooled is wound up by cooling with the splashing cooling water to the steel strip guide body 6 by jetting the cooling water 8 from the full cone type nozzle 7.

[0012]

According to the apparatus of the present invention, it is possible to travel on the hot run table while surely preventing the leading end of the traveling steel strip from entering between the rollers, so that the line stop can be avoided and the hot rolling mill The operating rate can be improved and productivity can be increased. Moreover, the yield of the hot rolled steel strip can be improved. Further, by cooling the steel strip guide body in the cooling stop zone, durability can be improved, and uniform cooling in the steel strip width direction can be ensured, so that uniform mechanical properties can be provided. Excellent effect can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing an outline of a main part of a device of the present invention.

FIG. 2 is a plan view showing an embodiment of the device of the present invention.

FIG. 3 is a side view showing an embodiment of the device of the present invention.

FIG. 4 is a perspective view showing a conventional hot run table cooling device.

[Explanation of symbols]

 1 Roller 2 Hot run table 3 Steel strip 6 Steel strip guide body 7 Full cone type nozzle 9 Guide body Cooling water supply port

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location C21D 9/52 102 C21D 9/52 102 9/573 101 9/573 101Z (72) Inventor Muranaka Kiyoshi, 5-3 Tokai-cho, Tokai-shi, Aichi Nippon Steel Co., Ltd. Nagoya Steel Works

Claims (2)

[Claims] 1. A steel strip guide body is provided immediately below a running position of the steel strip in a widthwise central portion between hot run table rollers of a hot rolling facility, and a steel strip guide body is provided with a guide body cooling water supply port. A cooling device for a lower surface of a hot-rolled steel strip, characterized in that a full-cone nozzle is arranged under a running steel strip between rollers at both ends of the strip guide body. 2. The cooling device for the lower surface of the hot-rolled steel strip according to claim 1, wherein the steel strip guide body is provided with a steel strip cooling water supply port.