KR20030053097A - Device for cooling of hot rolled wire rode - Google Patents

Abstract

PURPOSE: A hot rolled wire rod cooling device is provided to automatically control a temperature distribution of a material to be cooled by spraying cool air through a nozzle installed in a cooling table. CONSTITUTION: A hot rolled wire rod cooling device includes a rolling mill(10), a water-cooling device(20), a laying head(30), a conveying roll(50), a wire rod cooling table(600), a temperature sensor(700), a remote I/O(800), and a controller(900). The wire rod cooling table(600) has an air-cooled nozzle installed at a sidewall and a ceiling of the cooling table(600) so as to spray cooling air towards a hot rolled wire rod(40), a mist nozzle installed at a sidewall and a ceiling of the cooling table(600) so as to spray mist towards the hot rolled wire rod(40), and a water curtain creating section installed at the ceiling of the cooling table(600) so as to spray cooling water towards a hot rolled wire rod(40) in a form of an air curtain.

Description

Cooling device for rolled wires {DEVICE FOR COOLING OF HOT ROLLED WIRE RODE}

The present invention relates to an air-cooling device for a rolled wire rod, and more particularly, to a cooling device for a rolled wire rod for automatically controlling a temperature distribution of a current cooling target during cooling of a high-temperature wire rod capable of uniform cooling.

Stallmor is the most widely used method of cooling rolled wires worldwide. As shown in FIG. 1, this method forms a rolled wire of 800 to 900 DEG C in a winding machine, and then drops it onto a feed roll and drops it from the blower at the bottom of the feed roll while transferring it to a non-concentric ring state. It is a method of blowing by cooling cooling air of ˜50 m / sec.

1 is a view for explaining a cooling device of a general rolled wire rod.

Referring to FIG. 1, the rolled wire 40 that is rolled by the rolling mill 10 and cooled by the water cooling device 20 is wound by a winding head 30 to ring on the transfer roll 50. It is stacked in shape and transported. At this time, the cooling air injected through the slit-shaped nozzle from the blower 70 installed in the lower portion of the transfer roll directly cools the wire rod from the bottom. Here, ▽ on the drawing is a point where a constant thermometer is installed.

As a means for adjusting the flow velocity in the width direction, a blower angle adjusting device called a damper is provided in the blower, and a partition 60 is provided at the rear end of the damper so that the flow rate once divided is not mixed again.

However, the cooling rate of the wire rod obtained by the Stelmore method is low, it is difficult to produce a wire rod having a desired strength. In order to solve this problem, a spray cooling method and a mist cooling method have been proposed in which water is sprayed with fine particles or water is mixed with cooling air for spraying.

However, these methods have a problem in that the variation in the cooling rate occurring in the ring-shaped wire rod is simply focused on increasing the cooling capacity of the cooling medium.

Recently, in order to make the temperature distribution in the width direction uniform, the number of nozzles in the width direction is different by arranging nozzles in the width direction while spraying the same amount of spray or mist cooling water on the upper and lower surfaces during wire transfer. The method, the method of spraying mist cooling water only in the edge part with high overlapping density, etc. are proposed.

2 is a view showing the weight ratio in the coil width direction according to the overlapping state of the wire rod.

Referring to FIG. 2, it can be seen that when the center is 1.0, both ends are very large (3.0 to 5.0). Therefore, it can be estimated that the required cooling amount at both ends should also be increased in proportion to this. At this time, if the amount of cooling air is the same in the width direction, the cooling speed of both ends is inevitably lowered compared to the center part. Therefore, in order to control this, the area of the cooling air discharge part, that is, the nozzle part, or the quantity of nozzles is set unevenly in the width direction or the blower angle Angle) and blower speed.

However, the method of reducing the widthwise temperature deviation by adjusting the widthwise airflow amount by changing the airflow angle is to control the area of the wind in the duct through which air flows at high speed. The same flow velocity distribution tends to be obtained by vibration, resulting in poor resolution during control.

Therefore, the control means currently used has a limit to reduce the temperature deviation of the edge portion and the center portion, in particular, even in the same edge portion when cooling only by air due to the nonuniformity of the overlap density, the cooling rate is also lowered, causing a cooling deviation. .

In order to solve this problem, a method of spraying spray or mist cooling water has been proposed, but all of these improvements are simply spraying mist or spraying from the upper or lower surface of the wire rod to reduce the cooling variation, which is problematic. There is no proposal for facility interference or the like.

3 is a diagram showing the temperature distribution in the width direction of the wire rod cooling zone.

Referring to FIG. 3, in the width direction, it can be seen that the temperature of both ends having a high overlap density is higher than the temperature of the central part having a low overlap density. An example of the widthwise temperature distribution measured at a wire rod cooling stand in a wire rod factory shows that the temperature varies due to the width accumulation density difference.

In addition, because the mist is a mixture of air and water, the system is complicated and requires a lot of energy, and there is no suggestion regarding immediate control according to overlapping density in the width direction or changing factors.

Accordingly, the technical and problem of the present invention is to solve such a conventional problem, and an object of the present invention is to cool the wire rod in the middle of transferring the wire rod immediately after being rolled on the feed roll of the wire rod cooling stand in the form of a ring of a constant pitch. The present invention provides a cooling device for a rolled wire rod for automatically controlling a temperature distribution of a current cooling target in a cooling device for a rolled wire rod for cooling the wire rod by cooling air injected from a large nozzle.

1 is a view for explaining a cooling device of a general rolled wire rod.

2 is a view showing the weight ratio in the coil width direction according to the overlapping state of the wire rod.

3 is a diagram showing the temperature distribution in the width direction of the wire rod cooling zone.

4 is a view for explaining a cooling device for a rolled wire rod according to the present invention.

5 is a graph showing the cooling capacity of the mist

6A is a cross-sectional view of the wire rod cooling stand according to the present invention, and FIG. 6B is a conceptual view for explaining a cooling process using the wire rod cooling stand.

7A is a graph illustrating a case where the tensile strength deviation is severe, and FIG. 7B is a graph illustrating the small case of the tensile strength deviation.

<Description of the symbols for the main parts of the drawings>

10: rolling mill 20: water cooling device

30: winding machine 40: rolled wire rod

50: feed roll 60: partition

70: blower 600: wire rod cooling table

700 Temperature sensor 800 Remote I / O

900: injection flow rate controller

The cooling device for a rolled wire rod according to one feature for realizing the object of the present invention is to process the rolled wire rod immediately after rolling into a ring shape of a predetermined pitch through a winding machine, while loading and transporting on the feed roll of the wire rod cooling stand. In the cooling apparatus of the rolling wire which cools a rolled wire,

A plurality of air-cooling nozzles installed on the sidewalls and the ceiling of the wire rod cooling stand and spraying predetermined cooling air to the side of the rolled wire rod which is being transferred;

A plurality of mist nozzles installed on the sidewalls and the ceiling of the wire rod cooling unit and spraying a predetermined cooling mist on the side of the rolled wire rod which is being transferred;

A plurality of temperature sensors installed at at least one of a side wall portion or a ceiling of the wire rod cooling stand to measure temperature of the rolled wire rod and output temperature data; And

Compute the temperature distribution based on the temperature data provided from the temperature sensor, and control the cooling mist injection amount of the mist nozzle in response to the calculated temperature distribution to uniformly cool the rolling wire in the wire rod cooling zone It comprises a control unit to control.

Here, it is preferable that the cooling device of the rolled wire rod further includes a plurality of water curtain generators installed at the ceiling of the wire rod cooling stand to supply cooling water curtains to the rolling wire rod being transferred. Preferably, the water curtain is supplied to the center portion of the rolled wire rod being transferred, and the mist nozzle is supplied to the edge portion of the rolled wire rod being transferred.

According to the air-cooling apparatus of such a rolled wire rod, a plurality of mist nozzles are arranged on the ceiling and side walls of the wire rod cooling stand to cool the rolled wire rod, a water curtain is further arranged on the ceiling of the wire rod cooling stand, and the detected temperature of the current cooling target. By dynamically controlling the injection amount of the mist nozzle and the injection amount of the water curtain based on the distribution, the temperature distribution can be uniformly controlled while quenching the rolled wire rod in the wire rod cooling stand.

Hereinafter, with reference to the accompanying drawings, it will be described in detail the present invention.

4 is a view for explaining a cooling device for a rolled wire rod according to the present invention.

Referring to FIG. 4, the cooling apparatus of the rolled wire according to the present invention includes a rolling mill 10, a water cooling device 20, a winding machine 30, a transfer roll 50, a wire rod cooling stand 600, and a temperature sensor 700. ), A remote I / O 800 and a controller for controlling the injection flow rate 900, and the same reference numerals are assigned to the same components as compared with FIG. 1, and description thereof will be omitted.

The wire rod cooling stand 600 is installed at the side wall portion and the ceiling portion, and is provided with an air cooling nozzle for spraying constant cooling air to the side of the rolled wire 40, and the side wall portion and the ceiling portion are provided with a mist for constant cooling. It includes a mist nozzle (not shown) to be sprayed on, and a water curtain generating unit (not shown) for spraying a water curtain provided on the ceiling and sprayed in the curtain type on the rolled wire 40 side.

In particular, a large number of mist nozzles are arranged on the ceiling or sidewalls of the wire rod cooling stand 600 for uniform quenching, and the edge portions (preferably the side wall portions of the wire rod cooling stand) that require high cooling speed due to the high overlap density of the wire rods are often used. Place a large amount of mist nozzles, and place a small amount of mist nozzles in the center (preferably ceiling of the wire rod cooler) with low overlap density and low mist, and mist for each nozzle according to dimensions, steel grade and cooling conditions. It is preferable to vary the injection amount of.

The cooling capacity by the mist mentioned above is shown in FIG.

5 is a graph showing the cooling capacity of the mist, in particular showing the tendency and variation of the tensile strength (TS) according to the cooling capacity of the mist.

As such, according to the mist cooling, it is possible to produce a wire rod product having high tensile strength by improving the cooling capacity.

On the other hand, the temperature sensor 700 measures the widthwise temperature distribution of the wire rod 40 is transferred to the transfer roll and provides the measured temperature to the controller 900 via the remote I / O 800. Of course, in the drawings, for convenience of description, the temperature sensor 700 is located at the output end side of the wire rod cooling stand 600, but it is preferable to be located in the middle of the wire rod cooling stand 600, wire rod cooling. It may be preferable to be disposed on the same line as the mist nozzle or the water curtain which are arranged on the same line among the cut surfaces of the table 600.

In addition, the temperature sensor 700 is preferably installed at a position 10 to 20m away from the winder 30, it is preferable that the mist nozzles are arranged about 10 at regular intervals in the width direction.

The controller 900 receives a plurality of temperature values provided from a plurality of temperature sensors and converts them into a constant temperature distribution, and each spraying capability of the mist nozzle and the water curtain provided in the wire rod cooling stand based on the converted temperature distribution. To control. That is, when it is determined that the measured temperature is higher than the predetermined temperature value, the spraying amount of the mist nozzle or the spraying of the water curtain sprayed on the rolled wire in response to the measured temperature is controlled to control the temperature distribution to be uniform.

In addition, the controller 900 controls the mist particles entering the lower blower to cool the lower part of the wire rod by setting the lower blowing speed of the feed roll and the upper mist spraying speed of the feed roll to improve the wire cooling deviation of the upper and lower parts of the rolled wire rod. .

In the cooling operation, the temperature distribution measured from the temperature sensor 700 is transmitted to the injection flow rate control controller 900 via the remote I / O (remote input / output unit) 800. For example, control information is given to each nozzle from the temperature value detected at ten positions in the width direction, and the injection amount is automatically controlled.

In this way, a nonuniform temperature distribution in the width direction is detected and a uniform temperature distribution can be maintained by automatically controlling the injection amount of the cooling nozzle. The changing temperature distribution can then be visually checked on the production line's monitor.

6A is a cross-sectional view of the wire rod cooling stand according to the present invention, and FIG. 6B is a conceptual view for explaining a cooling process using the wire rod cooling stand.

As shown in FIGS. 6A and 6B, the wire rod cooling stand according to the present invention includes first and second side wall portions 650a and 650b between the left and right side walls 610a and 610b and the ceiling portion 630, respectively. A first coolant spray nozzle 650a is formed on the sidewall portion 650a, a second coolant spray nozzle 650b is formed on the second sidewall portion, and a slit lamina jet 640 is formed on the ceiling. Of course, since the cross section of the wire cooling stand is illustrated in the drawings, it is obvious that a plurality of the first cooling water injection nozzles 650a, the second cooling water injection nozzles 650b, and the slit lamina jet 640 are provided in the longitudinal direction of the wire cooling stand.

In addition, although not shown in the drawings, it is preferable to further include a temperature sensor for detecting the temperature of the rolled wire which is conveyed through the feed roll in proximity to the cooling water injection nozzle or the slit lamina jet, and the number of temperature sensors controls the injection amount. Although it will be suitable if it is a quantity for making it, the same thing as the number of cooling water injection nozzles is preferable.

Next, the cooling process of the rolled wire rod using the wire rod cooling stand will be described with reference to FIG. 5B.

Slit lamina jet or water curtain is used in the whole or part of the center part of the rolled wire, preferably in the center part, and mist or spray nozzle with excellent cooling ability is used in the edge part where the rolled wire is heavily overlapped. Reduce

As described above, according to the present invention, the rolled wire rod can be uniformly cooled by immediately performing spraying of cooling water or spraying of a water curtain in response to a change in temperature distribution according to operating conditions.

Moreover, the temperature distribution of the width direction can be made uniform by adjusting the cooling amount of the center part and the edge part of a rolled wire rod according to the measurement result by the temperature sensor 700. FIG.

In addition, by attaching the mist nozzle to the cover and the side wall portion of the wire cooling stand, it is possible to use a quenching device and a slow cooling device through the mist, and slow cooling is also possible by attaching an electric heating device or a warm air heating device to the existing cover.

In addition, by providing the slit lamina jet (or water curtain) together with the mist nozzle in order to reduce the cooling deviation caused by the mist cooling, the cooling variation in the width direction of the rolled wire can be reduced.

7A is a graph illustrating a case where the tensile strength deviation is severe, and FIG. 7B is a graph illustrating the small case of the tensile strength deviation. Here, the variation in tensile strength is one of the important problems that can cause problems such as disconnection during the drawing process in the secondary process.

As shown in Figure 7a and 7b, according to the present invention when using the slit lamina jet or water curtain can reduce the variation in tensile strength.

Although described above with reference to the embodiments, those skilled in the art can be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below. I can understand.

As described above, according to the present invention, the temperature distribution in the width direction is calculated through the temperature sensor installed in the middle of the wire rod cooling stand for uniform quenching in the wire rod cooling stand, and the wire rod cooling stand cover and the side wall portion are changed according to the change of operation factor. By uniformly controlling the injection amount of the attached mist, a uniform temperature distribution can be obtained, thereby reducing the material variation in the width direction caused by non-uniform cooling of the cooling target.

In addition, according to the present invention, in order to obtain a cooling rate such that the demand can omit the heat treatment, mist injection in the upper portion is preferable in addition to air blowing in the lower portion.

Further, according to the present invention, while cooling can be performed by adjusting the mist injection pressure according to the lower blowing speed, the temperature distribution can be uniformly controlled by detecting the variation factor caused by the change of the operating factors in the coil and the coil.

In addition, according to the present invention, even when the slow coolant working, there is no need for a separate transfer device is possible to quickly switch, and there is no need for an auxiliary device such as a pipe on the top to prevent the interference caused by splash water. The advantage of the mist cooling through the cover and the side wall portion is that a higher cooling rate can be obtained through the side cooling at the edge with a high overlap density, thereby enabling uniform cooling.

In addition, while conventionally, it is possible to produce a wire rod product having high tensile strength by improving cooling capability by mist cooling, but there is a limit in reducing cooling variation. However, by installing the slit lamina jet together with the mist, the widthwise cooling variation is reduced. Can be reduced.

Claims (3)

In the cooling device for a rolled wire rod which cools the rolled wire rod while processing the rolled wire rod immediately after rolling in the form of a ring of a constant pitch through a winding machine to be deposited and transferred on the feed roll of the wire rod cooling stand, A plurality of air-cooling nozzles installed on the sidewalls and the ceiling of the wire rod cooling stand and spraying predetermined cooling air to the side of the rolled wire rod which is being transferred; A plurality of mist nozzles installed on the sidewalls and the ceiling of the wire rod cooling unit and spraying a predetermined cooling mist on the side of the rolled wire rod which is being transferred; A plurality of temperature sensors installed at at least one of a side wall portion or a ceiling of the wire rod cooling stand to measure temperature of the rolled wire rod and output temperature data; And Compute the temperature distribution based on the temperature data provided from the temperature sensor, and control the cooling mist injection amount of the mist nozzle in response to the calculated temperature distribution to uniformly cool the rolling wire in the wire rod cooling zone Cooling device for a rolled wire comprising a control unit for controlling. The cooling device of the rolled wire according to claim 1, And a plurality of water curtain generators installed at the ceiling of the wire rod cooling unit and supplying the cooling water curtain to the rolling wire rod being transferred. The cooling of the rolled wire rod according to claim 2, wherein the water curtain generating unit supplies the water curtain to a central portion of the rolled wire rod being transferred, and the mist nozzle supplies the mist to an edge portion of the rolled wire rod being transferred. Device.