JPH0788530A - Cooling nozzle for hot rolled steel sheet or the like - Google Patents

Abstract

PURPOSE:To make cooling water jetted uniform, to relatively easily make the quantity of water constant, to execute flow rate control in a comparatively wide range and further to improve imbalance in heat transmission by providing an orifice ring besides forming a stepped part in a nozzle body. CONSTITUTION:In a cooling nozzle 10, the cooling water which flows into each nozzle body 12, 12a from a nozzle adapter 11 along the longitudinal direction of a rectangular nozzle hole where is provided in the tip part of the nozzle body 12, 12a is rapidly accelerated in the orifice part which is divided with the orifice ring 17. Then, the cooling water velocity is rapidly reduced in expanding area on the downstream side and the cooling water is spreaded and jetted against the hot rolled steel sheet. At this time, the jetting patterns of cooling water from two nozzle bodies 12, 12a are uniformized in a relatively wide range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling nozzle, and more particularly to a nozzle for cooling a hot rolled steel sheet.

This kind of cooling nozzle can be effectively used, for example, by installing it in a production line at the time of manufacturing a rolled steel sheet and continuously cooling the hot rolled steel sheet.

[0003]

2. Description of the Related Art An example of this type of cooling nozzle is disclosed in Japanese Patent Laid-Open No. 62-170422. In this Japanese Laid-Open Patent Publication No. 62-170422, a large number of slit laminar nozzles are arranged in the width direction of the steel plate for the steel plate to be hot rolled and transferred, and pipe laminar nozzles are similarly provided between these slit laminar nozzles. Disclosed is a cooling configuration for hot-rolled steel plates arranged in a large number in the width direction of the steel plate. In the present invention, it is intended to control the water injection by appropriately combining the nozzles of the slit laminar and the pipe laminar, and to realize the control of the cooling rate.

[0004]

However, Japanese Unexamined Patent Application Publication No. Sho 6
In the configuration of JP-A 2-170422, since the water pressure required for the pipe laminar nozzle is relatively extremely low at 1 Kg / cm ² or less, the ejection from the nozzle is made uniform and the water amount is made constant. However, there is a problem that extremely complicated adjustment work is required and the flow rate control range is extremely narrowed in order to maintain the laminar flow. In addition, there is a big difference in the cooling capacity, that is, the heat transfer coefficient, between the immediately lower portion and the peripheral portion of the laminar flow fed to the steel plate, and there is a fear that the peripheral portion may have 1/10 or less of the local cooling in the lower portion. It was

Therefore, an object of the present invention is to improve the above-mentioned problems of the conventional cooling nozzle with a simple structure, to make the jetted cooling water uniform, and to make the amount of water constant relatively easily. The present invention provides a cooling nozzle capable of controlling the flow rate in a relatively wide range and further improving the imbalance of heat transfer.

[0006]

The above object of the present invention is to provide a nozzle body 11 with a nozzle body accommodating portion 13 capable of mounting at least one nozzle body 12 so that the flow velocity of cooling water can be increased in the nozzle body 12. The orifice ring 17 is installed and the nozzle body 12
This is achieved by a cooling nozzle such as a hot-rolled steel plate in which a concave portion 14 is provided at a wide angle at the tip of the and a nozzle hole 15 is provided in the concave portion 14.

[0007]

In the cooling nozzle 10 of the present invention having the above-described structure, the step portion 16, especially in the nozzle body 12, 12a,
Since 16a is formed and the orifice rings 17 and 17a are installed, the cooling water flowing in the nozzle bodies 12 and 12a is rapidly accelerated at the orifice portion by the orifice rings 17 and 17a, and then the orifice rings 17 and 17a.
The flow velocity is reduced and diffused in the downstream expanded region, and the jet pattern is effectively made uniform.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1-3, there is shown a cooling nozzle 10 for hot rolled steel sheets and the like according to the present invention. The cooling nozzle 10 includes a nozzle adapter 11,
Nozzle body accommodating portions 13 and 13a are preferably partitioned in the nozzle adapter 11 so that two nozzle bodies 12 and 12a can be arranged side by side.
The bases of the nozzle bodies 12 and 12a are provided on the seat 3a so that they can be seated. The tip of the nozzle body 12, 12a is provided with a recess 14, 14a which is cut open in a range close to about 180 °.
Is formed (see also FIG. 4), and in the recesses 14 and 14a, slit-shaped nozzle holes 15 and 1 having a rectangular shape when viewed from the bottom surface are formed.
5a is formed. This allows the nozzle adapter 11
The cooling water that has flowed into the nozzle is branched and introduced into the two nozzle bodies 12 and 12a through a part of the nozzle body accommodating portions 13 and 13a, and is smoothly ejected from the rectangular slit-shaped nozzle holes 15 and 15a of the recesses 14 and 14a. It will be.

Further, in the cooling nozzle 10 of this embodiment, it is contemplated that the nozzle bodies 12, 12a are installed so that they can be ejected relatively widely and uniformly from the nozzle holes 15, 15a of the nozzle bodies 12, 12a. That is, the nozzle body accommodating portions 13 and 13a of the nozzle adapter 11 are center lines BC and B of the nozzle bodies 12 and 12a whose bases are seated in the nozzle body accommodating portions 13 and 13a, respectively.
Ca is installed at an angle of 2 to 10 degrees with respect to the center line AC of the nozzle adapter 11.

Further, the nozzle body 1 of the cooling nozzle 10
In the inside of 2, 12a, for example, in the vicinity of the central portion, the step portions 16, 1
6a is formed, and this nozzle body 12, 12a
The orientation rings 17 and 17a are seated and installed on the. By installing the orifice rings 17 and 17a, an orifice portion can be formed in the flow path in the nozzle body 12 and 12a.

In the cooling nozzle 10 constructed as described above, however, as is apparent from the cross-sectional view of FIG. 4 taken along the longitudinal direction of the rectangular nozzle holes 15 and 15a provided at the tips of the nozzle bodies 12 and 12a. , Nozzle adapter 1
After the cooling water that has flowed into each nozzle body 12, 12a from 1 is rapidly accelerated in the orifice portion defined by the orifice ring 17, 17a, the orifice ring 17,
It is rapidly lowered and diffused in the expansion region downstream of 17a, and is jetted to the hot-rolled steel sheet. At this time, it was confirmed that the jet pattern of the cooling water was uniform over a wide range as indicated by the curve PA1 in FIG. Further, the cooling water flowing from the nozzle adapter 11 into each nozzle body 12, 12a has a rectangular cross section along the width direction of the rectangular nozzle holes 15, 15a provided at the tips of the nozzle bodies 12, 12a. Ring 1
After being rapidly accelerated in the orifice portion partitioned by 7, 17a, the acceleration is rapidly reduced and diffused in the expansion region downstream of the orifice ring 17, 17a, and is diffused and jetted to the hot-rolled steel sheet. It At this time, it was confirmed that the jet patterns of the cooling water from the two nozzle bodies 12 and 12a were uniform over a relatively wide range as shown by the curve PA2 in FIG.

In this case, the conventional cooling nozzle having a nozzle hole has a ridge-shaped ejection pattern having no flat portion at the top, whereas the PA1 and PA2 of the present invention provide a wide uniform ejection area. It will be. Further, according to the cooling structure in which the cooling nozzles 10 are arranged in the longitudinal direction of the hot rolled steel sheet HS, the hot rolled steel sheet HS of about 850 ° C. is heated up to about 500 ° C. as shown by the line T in FIG. It was confirmed that the cooling was good. In addition, the above-mentioned FIG.
The cooling nozzle of the present invention was used to cool a rolled steel sheet, with a sheet thickness of 4 mm, a sheet width of 1200 mm and a finishing temperature of 860 ° C.
The results are shown when the film is cooled under conditions of a winding temperature of 500 ° C. and a transfer speed of 600 mpm. On the other hand, in the case of conventional laminar cooling, under the same conditions as above, the fluctuation range of the winding temperature was ± 50 ° C both in the plate longitudinal direction and in the width direction, and there were some variations in the material between the laminar part and the peripheral part. However, according to the cooling nozzle of the present invention, the fluctuation range of the winding temperature is the plate length,
It was found that the temperature was ± 20 ° C. in both width directions, and that the quality of the product could be remarkably improved without any variation in the material.

More specifically, as shown in FIGS. 9 and 10, in the cooling nozzle 10 according to the present invention, the longitudinal direction of the rectangular nozzle holes 15 and 15a provided in the nozzle body 12 and 12a is preferably higher than that of the nozzle head 20. Across the width of the cold rolled steel plate HS and the nozzle body 1
The width directions of the rectangular nozzle holes 15 and 15a provided in 2 and 12a are arranged along the longitudinal direction of the hot rolled steel plate HS. At this time, it is preferable that each cooling nozzle 10 gives good PA1 and PA2 to the hot-rolled steel sheet HS, for example, and the interval P is set to 300 to 500 mm.

[0014]

According to the cooling nozzle 10 of the present invention constructed as described above, the cooling water jetted to the object is effectively made uniform, and the jetted water amount is also made constant accordingly. It can be achieved, and since the jets are made uniform over a wide range, it is possible to realize flow control in a considerably wide range.
Further, effects such as effective improvement of heat transfer imbalance are achieved.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of a cooling nozzle according to the present invention.

FIG. 2 is a bottom view of the cooling nozzle of FIG.

3 is a cross-sectional view of the cooling nozzle of FIG.

FIG. 4 is an operation explanatory diagram of the cooling nozzle of FIG. 1.

5 is an explanatory view of a jetting pattern along a longitudinal direction of a nozzle hole in the cooling nozzle of FIG.

6 is another operation explanatory diagram of the cooling nozzle of FIG. 1. FIG.

FIG. 7 is an explanatory diagram of a jetting pattern along the width direction of the nozzle hole in the cooling nozzle of FIG.

FIG. 8 is a graph showing a cooling state by the cooling nozzle of FIG.

FIG. 9 is a simplified front view of a specific installation state of the cooling nozzle of FIG.

FIG. 10 is a simplified side view of a specific installation state of the cooling nozzle of FIG.

[Explanation of symbols]

 10 Cooling Nozzle 11 Nozzle Adapter 12 Nozzle Body 12a Nozzle Body 13 Nozzle Body Housing 13a Nozzle Body Housing 14 Recess 14a Recess 15 Nozzle Hole 15a Nozzle Hole 16 Step 16a Step 17 Center Wheel Ring 20a Center Wh C Line BCa Center line PA1 Ejection pattern PA2 Ejection pattern HS Hot rolled steel sheet

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shunichi Akiyama Marunouchi 1-2-2, Chiyoda-ku, Tokyo Japan Steel Pipe Co., Ltd. (72) Inventor Ken Tada 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Date Main Steel Pipe Co., Ltd. (72) Inventor Masashi Hori 1-2-2 Marunouchi, Chiyoda-ku, Tokyo Japan Steel Pipe Co., Ltd. (72) Inventor Yoshiya Kashiwazaki 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Japan Steel Pipe (72) Inventor Masaki Yamamoto 487-1 Iikura, Yokaichiichi, Chiba Employment Promotion Housing 2-202 (72) Inventor Yasuomi Akechi 1613-5 Egasaki, Asahi-shi, Chiba

Claims (4)

[Claims] 1. A nozzle body accommodating portion 13 capable of mounting at least one nozzle body 12 in a nozzle adapter 11.
Is provided, an orifice ring 17 capable of increasing the flow velocity of the cooling water is installed in the nozzle body 12, a recess 14 is provided at the tip of the nozzle body 12 at a wide angle, and a nozzle hole is provided in the recess 14. A nozzle for cooling a hot-rolled steel plate or the like provided with 15. 2. The cooling nozzle according to claim 1, wherein the nozzle hole 15 is provided in a rectangular slit shape. 3. The cooling device according to claim 1, wherein two nozzle body accommodating portions 13, 13a are provided in the nozzle adapter 11, and the nozzle body 12, 12a is seated in each nozzle body accommodating portion 13, 13a. nozzle. 4. The nozzle bodies 12, 12a are 2 to each other.
The cooling nozzle according to claim 3, wherein the nozzle body accommodating portions 13, 13a of the nozzle adapter 11 are provided so as to form 10 degrees.