JPS5950409B2 - Rolled material cooling method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for cooling rolled material suitable for use in hot rolling lines such as hot strip mills and plate mills.

Generally, in a hot rolling line, a slab heated to a predetermined rolling temperature in a heating furnace is rolled in a rough rolling mill and a finishing mill to form a strip with a predetermined width and thickness, and then rolled up. It is designed to be taken up by a machine.

Here, after the strip is finish rolled in a finish rolling mill at a rolling temperature of A3 transformation point or higher (750°C to 900°C), the strip is rolled at a temperature required for the material (500°C) before being wound up in a winding machine. ℃~600℃).

Therefore, conventionally, a hot run table equipped with a cooling device that can cool the strip is disposed between the finishing mill and the winding machine.

FIG. 1 is an explanatory diagram showing a conventional cooling device in a hot strip rolling line.

While the finish-rolled strip 1 is being conveyed by the table rollers 2, it is cooled to a predetermined temperature by cooling flows supplied from the upper and lower headers 3 and 4 installed above and below the strip passageway. It has become.

Here, the lower header 4 supplies a cooling flow from a nozzle facing the lower surface of the strip 1 by spraying, and the upper header 3 supplies a cooling flow when passing the strip 1 in order to prevent nozzle interference when passing the tip of the strip. to L (1.5-2m)
The cooling flow is supplied by a one-sided lamina system that prevents the water flow from spreading even when separated by a distance.

In addition, the upper header 3 and the lower header 4 each form a plurality of cooling sections by aggregating several pieces, and through valves 5 and 6 provided in each cooling section,
The amount of cooling flow supplied to the strip is controlled, making it possible to control the cooling temperature of the strip.

However, the heat transfer coefficient in conventional cooling equipment is 1000Kcal/m2h even if the supply amount of cooling flow is increased.
As low as r'c.

Therefore, since the cooling efficiency of conventional concrete cooling devices is low, for example, the total number of cooling sections is 11.
The overall length of the cooling system is 170 m, the cooling water supply rate is 7200 m''/hr, and three 340 KW cooling water pressure pipes are required, making the equipment larger. There is.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a method for cooling rolled material that has high cooling efficiency and can reduce the size of equipment.

In order to achieve the above object, the method for cooling a rolled material according to the present invention has a heat transfer coefficient of 10.
000Kcal/m2hr'c ~15.0OOKca
This was done by paying attention to the fact that the water flow is as high as 1/m2hr℃, and is applied to the upper header, the lower header, and the spout portions of both headers that stay at the water film formation position close to the upper and lower surfaces of the rolled material. A rolled material cooling method in which a water film flow in contact with the upper and lower surfaces of the rolled material is formed by a flat guide along the rolled material surface provided, and the rolled material can be cooled by the water film flow, the upper header comprising: When the leading end of the rolled material is passed through, it remains at a position above the water film flow forming position, so that a laminar flow cooling flow can be supplied to the upper surface of the rolled material.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is an explanatory diagram showing a cooling device for a hot strip rolling line to which the method for cooling rolled material according to the present invention is applied. A header device 10 and a lower header device 30 are provided.

FIG. 3 is an explanatory diagram showing a specific configuration of the upper header device 10.

A pedestal 11 and a guide frame 15 are fixedly arranged on both sides of the strip passageway formed by the table roller 2.

A position adjustment jack 12 is provided at the top of the pedestal 11.

At the top of the guide frame 15, a vertical movement motor 16,
Sprocket 1 driven by vertical motor 16
A chain 18 is wound around the sprocket 17, and a support beam 13 in a horizontal state is connected to one end of the chain 18.

The support beam 13 is driven by a vertical movement motor 16.
The guide roller 14 is rolled along the guide rail 15A provided in the guide frame 15 via the sprocket 17 and the chain 18, and the position where the water film flow is formed is shown by the solid line in FIG. It is possible to move up and down within a distance of 1 from the upper position shown by.

Note that the supporting beam 13 that remains at the water film flow forming position can adjust its vertical stopping position by means of a position adjustment jack 12.

An upper header 19 is fixed to the lower part of the support beam 13.

The upper header 19 is provided with a nozzle 20 that opens at a predetermined position in the width direction of the strip passageway, and a flat guide 21 is integrated into the ejection opening of the nozzle 20.

The nozzle 20 is a slit nozzle or a circular tube nozzle, and is capable of supplying a complete laminar flow cooling flow such as a slit laminar flow or a rod-like flow to the upper surface of the strip when the upper header 19 is stopped at the upper position. ing.

In addition, when the upper header 19 stays at the water film flow forming position, the flat guide 21 forms a gap H with the upper surface of the strip 1, and allows the water flow ejected from the nozzle 20 to form a water film in this gap. The strip 1 can be cooled with a high heat transfer coefficient.

A wooden main pipe 24° is connected to the upper header 19 via a rotary joint 22 and an intermediate pipe 23.

In addition, in FIG. 3, 25 indicates a conveyance motor that drives the table roller 2.

The operation of the upper header device 10 is as follows.

When passing the tip of the strip 1, the upper header 19 remains at the upper position shown by the two-dot chain line in FIG. 3, and the nozzle 2
The strip 1 is cooled from its top surface by supplying a laminar flow cooling flow through the strip 1.

In addition, even if the strip tip part flies when passing the tip of the strip 1, the table roller 2
On the other hand, since the upper header 19 is far apart upward, the tip of the strip is connected to the nozzle 2 of the upper header 19.
The strip can be passed smoothly and cooled without contacting the surface.

When the leading end of the strip is wound up by a winder and the strip is threaded in a steady state, the vertical movement motor 16 is driven and the support beam 13 is positioned by the position adjustment jack 12, as shown in FIG. The upper header 19 moves to the lower position shown by the solid line and remains at the water film flow forming position.

At this water film flow forming position, the cooling flow ejected from the nozzle 20 of the upper header 19 is directed by the flat guide 21.
A water film flow is formed in the gap H formed between the IJ tube 1 and the upper surface, and the strip 1 is cooled from the upper surface with a high heat transfer coefficient.

In addition, if this hot strip rolling line is a completely continuous rolling line in which seed bars are sequentially joined online and rolled continuously, strip 1 is rolled over several coils or lots between a finishing mill and a winding machine. Since the upper header 19 is constantly passed through while receiving tension between the two, the upper header 19 remains in the water film forming position for a long period of time.
Strip 1 is continuously cooled with a high heat transfer rate.

It becomes possible.

FIG. 4 is an explanatory diagram showing the detailed structure of the lower header device 30.

A nozzle 32 is provided in the upper part of the lower header 31 at a predetermined position in the width direction of the strip passageway, and a flat guide 33 is integrated with the nozzle 32.

The flat guide 33 forms a predetermined gap between the strip passing path and the lower surface of the strip to be passed through, and the nozzle 3
A water stream ejected from the strip 2 is allowed to flow in the strip passing direction and the direction of the threading root to form a water film that comes into contact with the lower surface of the inserted strip 1.

Roller guides 34 that face the outer circumference of the table roller 2 with a predetermined gap therebetween are integrated into both ends of the flat guide 33, respectively.

The roller guide 34 is connected to the flat guide 33 and the strip 1.
The cooling water flowing out from between the bottom surface of the table roller 2
The table roller 2 can be cooled by being supplied to the outer peripheral part of the table roller 2.

Further, side guides 35 are disposed on the upper surfaces of both sides of the flat guide 33 to form side walls against the water film flow on both sides of the gap formed between the flat guide 33 and the lower surface of the strip 1.

The side guide 35 is a side guide shift cylinder 36
The actuator moves in the width direction of the strip plate, making it possible to form a water film flow of an appropriate width for strips 1 of various plate widths.

The operation of the lower header device 30 is as follows.

When the strip 1 is passed through, the cooling water ejected from the nozzle 32 becomes a water film flow that contacts the lower surface of the strip 1 by the flat guide 33, thereby cooling the strip 1 from the lower surface with a high heat transfer coefficient.

Further, the cooling water that has cooled the strip flows down the outer circumference of the table roller 2 by the roller guide 34, and also cools the table roller 2.

Further, when the width of the strip 1 is changed, the side guide shift cylinder 36 is operated to move the side guide 35 in the width direction of the strip, thereby changing the formation area of the water film flow.

As described above, according to the above embodiment including the upper header device 10 and the lower header device 30, the strip is cooled with a high heat transfer coefficient by the water film cooling method, so that the overall length of the cooling device is shortened. This improves equipment maintainability and strip threadability, shortens the length of the rolling line, and reduces the amount of cooling water supplied to the strip, reducing the consumption of cooling water and electricity consumption. It becomes possible to reduce the number of units.

In addition, the upper header device 10 stays at the upper position when passing the tip of the sl-IJ tube, and the strip can be cooled by the laminar flow cooling flow, so that the strip can be smoothly passed and cooled. I can do it.

In the lower header device 30 in the above embodiment, the cooling water spouted from the nozzle 32 is passed through the flat guide 33.
Although the case where the water film flow is formed by dividing the flow in both directions in the strip running direction has been described in the above, the nozzle 4 of the lower header 41 as in the lower header device 40 shown in FIG.
The cooling water spouted from 2 may flow out in one direction of the strip passing direction, and a water film flow may be formed by the flat guide 43.

In addition, in FIG. 5, 44 indicates a roller guide that guides cooling water so that the table roller 2 can be cooled.

Furthermore, in the rolling material cooling method according to the present invention, the water film flow is
Instead of being formed in the strip running direction as in the above embodiments, it may be formed in the strip width direction.

Further, the method for cooling a rolled material according to the present invention is applicable not only to a hot trip rolling line but also to a plate mill line.

As described above, in the method for cooling a rolled material according to the present invention, the water film flow in contact with the upper and lower surfaces of the rolled material is caused by the upper header and the lower header staying at the water film flow forming position close to the upper and lower surfaces of the rolled material. A method for cooling a rolled material by forming a water film flow to cool the rolled material, the upper header comprising:
When passing the leading end of the rolled material, it stays at a position above the water film flow forming position and can supply a laminar flow set cooling flow to the top surface of the rolled material, so cooling efficiency is high.
This has the effect that the equipment can be downsized.

[Brief explanation of drawings]

FIG. 1 is a side view showing a conventional method for cooling rolled material, FIG. 2 is a sectional view showing an embodiment of the method for cooling rolled material according to the present invention, and FIG. FIG. 4 is a front view showing details of the device, FIG. 4 is a perspective view showing details of the lower header device in the same embodiment, and FIG. 5 is a sectional view showing a modification of the lower header device. 1... Strip, 10... Upper header device, 19... Upper header, 20...
・Nozzle, 21... Flat guide, 30...
... lower header device, 31 ... lower header,
32... Nozzle, 33... Flat guide, 34... Roller guide, 35...
・Side guide.

Claims (1)

[Claims] 1. An upper header and a lower header that stay at a water film formation position close to the upper and lower surfaces of the rolled material and flat guides along the surface of the rolled material provided at the spout portions of both headers are used to apply water to the upper and lower surfaces of the rolled material. A rolled material cooling method that forms a contacting water film flow and allows the rolled material to be cooled by the water film flow, the method comprising:
The upper header remains at a position above the water film flow forming position when passing the leading end of the rolled material, and is capable of supplying a laminar flow set cooling flow to the upper surface of the rolled material.