JPH05115914A - Method and device for water cooling bar steel/wire rod - Google Patents

Abstract

PURPOSE:To provide a water cooling method and its device which can cool uniformly in the outer peripheral direction of a bar stock and a wire rod. CONSTITUTION:This water cooling device for the bar steel and wire rod provides a female engagement element 2 having a cooling water supply hole 5 and an engagement room 6 at one end of a water cooling tube 4, fins 8 revolving in one direction on one outer periphery, forms a male engagement element 3 provided with a hollow induction hole 9 and is constituted by engaging this male engagement element 3 with the female engagement element 2, and cooling is carried out by this water cooling method for the barstock and wire rod, the voltical cooling water having continuous colliding points is supplied from the longitudinal direction of the outer peripheral surface to the bar steel and the wire rod introduced into the water cooling device. Since high, stable and uniform cooling can be performed, the qualities of the bar stock and the wire rod can be improved. Further, since a desired cooling condition can be selected by combination of the male engagement element and the female engagement element, the cooling condition conforming to the quality requirement at which kinds of the bar steel and the wire rod aim can be maintained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water cooling method and a water cooling device for steel bars and wire rods, and more particularly to uniformly cooling the steel rod in the outer peripheral direction. In the following description of the present invention, a wire will be described as a typical example for convenience.

[0002]

2. Description of the Related Art In wire rod rolling, a water cooling device is provided between rolling roll groups to cool the wire rod so as to obtain desired metallographic structure and mechanical properties.

It is considered that this water cooling can be carried out as uniformly as possible. For example, there are the following prior art examples.

Although these prior arts should have been the best cooling systems in those times, they cannot always be said to be sufficient in the present age as the rolling technology advances and the quality requirements of consumers change.

That is, the spray swirl flow nozzle system is disclosed in Japanese Utility Model Publication No. 55-41813 (cooling trough), Japanese Patent Publication No. 63-
No. 45451 (cooling device for steel rod wire) belongs to it, and has the following problems.

Among these cooling methods, Japanese Examined Patent Publication No. 63-4
In No. 5451 (cooling device for steel rod wire), the upstream unit cools with high cooling capacity, and the downstream unit performs uniform cooling in the cross-sectional direction by swirling flow, in order to achieve both high cooling capacity and uniform cooling capacity. However, there is a problem that it is difficult to eliminate the temperature unevenness generated on the upstream side only in the downstream unit.

The direct injection nozzle on the upstream side has a high cooling capacity, but is inferior in uniform cooling capacity to the swirl flow nozzle.

Further, the system of this swirling flow generating nozzle has a double pipe structure in which cooling water jet holes are provided in the tangential direction of the inner wall of the inner pipe of the cooling pipe. Therefore, since the cooling water sprayed on the inner wall flows along the pipe wall, it is difficult to directly hit the wire rod at the center of the cooling pipe and to fill the cooling pipe with difficulty, so that not only the cooling ability is low, but also the desired cooling ability is not achieved. Stable and hard to get.

Further, there has been a problem that the flow velocity of the cooling water sprayed on the inner wall is attenuated, the flow below the cooling pipe is impaired, the metabolism is hindered, and uneven cooling of the wire is likely to occur.

Further, the cooling pipe system with fins in the pipe is the actual Kokoku Sho 5
No. 3-19122 (jacket for continuous cooling) belongs, and has the following problems.

This system has a double pipe structure in which the cooling water injection port is composed of an injection hole perpendicular to the traveling direction of the material to be cooled and a hole opened in the tangential direction of the cooling pipe, and a vortex flow is formed on the inner wall of the pipe. It is configured with fins for maintenance.

Therefore, since the fins are provided on the inner wall of the cooling pipe, there is a problem in the threadability at the rolling speed (maximum 100 m / s), and stable cooling cannot be expected. Further, there are problems in workability and cost due to the complexity of the structure.

Further, Japanese Examined Patent Publication Nos. 63-58207 and 63-
No. 58208 and 63-58209 (immersion cooling pipes for wire rods and steel bars) do not supply swirling cooling water, and the drainage port is not opened in the entire circumferential direction of the circular pipe. It was difficult to make the flow velocity uniform and there was a problem with the uniform cooling capacity.

[0014]

DISCLOSURE OF THE INVENTION The present invention solves the problems of the conventional method as described above and can stably obtain a desired cooling capacity, and the outer peripheral surface and the longitudinal direction of the bar steel / wire material (bar steel) in the cross-sectional direction. (EN) Provided are a water cooling method and a water cooling device for a steel bar / wire which can stably and uniformly cool a circumferential outer peripheral surface.

[0015]

The present invention has the following structures.

The first one is characterized in that a steel bar or a wire rod guided into a water cooling device is cooled while supplying eddy current cooling water having continuous collision points from the longitudinal direction of the outer peripheral surface thereof.・ Water cooling method for wire.

No. 2 is a steel bar as described above, which multi-stages cooling while supplying vortex-like cooling water having continuous collision points.
This is a water cooling method for the wire.

The third feature is that a female fitting element 2 having a cooling water supply hole 5 and a fitting chamber 6 is provided at one end of a water cooling pipe 4, and a fin 8 that swivels in one direction is provided on the outer periphery of the female fitting element 2. Water of a steel bar / wire rod, characterized in that a male fitting element 3 having a hollow guide hole 9 is formed, and the male fitting element 3 is fitted to the female fitting element 2. It is a cooling device.

No. 4 is a steel bar / wire water cooling device in which a water cooling device 1 constructed by fitting a male fitting element 3 to a female fitting element 2 is installed in multiple stages on a steel bar / wire guide line.

[0020]

In the water cooling apparatus of the present invention, the cooling water is supplied from the cooling water supply hole provided at one end of the water cooling pipe, and the female fitting element provided at this end and the female fitting element fitted therein. It passes through an annular space formed between the male fitting element and the male fitting element, and at this time, it is made into a vortex by fins which are provided in the outer periphery of the male fitting element and swirl in one direction.

Thereafter, the vortex-like cooling water is passed through an annular slit formed between the water cooling pipe side end of the female fitting element and the water cooling pipe side end of the male fitting element. The vortex-like cooling water toward the steel bar or wire rod running through the male fitting element axial center portion in the water cooling pipe from the outer peripheral surface longitudinal direction, and directly and continuously to the steel bar or wire rod. Then, it is cooled while being collided and supplied.

The vortex-like cooling water continuously supplied by collision is filled in the water cooling pipe, and the steel bar or the wire rod is immersed therein to be cooled.

Further, the vortex-like cooling water continuously collided and supplied is cooled by contacting the steel bar or the wire rod by controlling the fin angle θf of the fin 8 to a predetermined angle and controlling the pitch to a predetermined vortex flow pitch. To do.

Therefore, in the water cooling device of the present invention, the steel bar or wire is cooled with high cooling capacity and is cooled uniformly.

Here, the reason for limiting the essential requirements in the configuration of the present invention will be described.

In the first method, the reason why it is limited to "a vortex-like cooling water having continuous collision points in the longitudinal direction of the outer peripheral surface of the steel bar or wire".

First, the vortex-like cooling water having continuous collision points means that the cooling water supplied directly and continuously to the steel bar or the wire rod in the process of guiding the steel bar or the wire rod into the water cooling device. It is the cooling water that jets out and collides with each other in a vortex state.

It is important that the quality of the steel bar / wire is uniform not only in the cross-sectional direction but also in the longitudinal direction. Therefore, supplying the vortex-like cooling water having continuous collision points to the outer peripheral surface longitudinal direction of the steel bar / wire material suppresses the variation in the temperature gradient in the cross-sectional direction and the longitudinal direction, and eventually enables uniform cooling, This is a necessary condition for making quality uniform.

Then, the vortex-like cooling water having continuous collision points is brought into complete contact with the longitudinal direction of the outer peripheral surface of the steel bar / wire introduced into the water cooling device to stably obtain a desired cooling capacity. This is an essential condition.

In other words, supplying the cooling water in the form of swirl to cool the longitudinal direction of the outer peripheral surface of the steel bar / wire can be seen in the above-mentioned prior art examples. The cooling water is swirling cooling water having discontinuous collision points.

The vortex-like cooling water having the discontinuous collision points is hard to fill the inside of the pipe and generates a non-contact portion with the longitudinal direction of the outer peripheral surface of the steel bar / wire, and since there is a void, the cooling water itself is the cooling pipe. There was a tendency to stay in the lower part, and it was difficult to say that the vortex flow state was uniform in the cross sectional direction of the pipe. Therefore, in these prior art examples, the desired cooling ability was not stably obtained, and the uniform cooling property was also poor.

Therefore, as compared with the swirling cooling water having discontinuous collision points in these prior art examples, the swirling cooling water having continuous collision points of the present invention is uniform and uniform in quality. Is excellent in terms of.

In the present invention, the vortex-like cooling water limited to the above may be supplied so as to oppose in the traveling direction of the steel bar / wire or in the direction opposite to the traveling direction. By supplying in the opposite direction, the repulsive kinetic energy with the kinetic energy in the running direction of the steel material makes it possible to present a state in which the contact interface in the longitudinal direction of the outer peripheral surface of the steel material and the swirling cooling water of the above conditions is washed. Therefore, it is possible to promote the metabolism of cooling water.

The cooling water exhibiting the vortex flow condition of the above-mentioned limited conditions is cooled while being sufficiently in contact with the longitudinal direction of the outer peripheral surface of the steel bar / wire, and the contact distance determines the desired cooling capacity of the cooling water. For this reason, in the present invention, the shape condition of the fin of the male fitting element to be fitted into the fitting chamber of the female fitting element is selected and fitted, and the distance in contact with the longitudinal direction is set to a desired distance, and continuous Swirling cooling water with colliding points
It is a desirable condition for stabilization that the reduction of the cooling ability of the cooling water, which is influenced by the outer peripheral surface contact distance of the wire, is suppressed.

In the second method of the present invention, the multi-stage cooling under the conditions of the first method is limited, but this is because even in the method of the present invention in which a high cooling capacity can be stably maintained. Depending on the standard (JIS) and the rolling speed, it may not be possible to guide heat to the next rolling mill by absorbing the heat generated during processing, or to adjust the temperature gradient in the cross-sectional direction of the steel bar / wire rod. It is essential from the rolling conditions of the wire rod.

The constitutional conditions limited by the device of the third aspect of the present invention are essential conditions for the reason of limitation by the method of the first aspect. Also, the technology to select the shape condition of the fin is
This is effective for simplifying and reducing the cost of the water cooling device or for selecting the eddy current conditions.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings.

FIG. 2 is an explanatory view showing an example of a wire rod rolling process in which the water cooling device 1 according to the present invention is arranged in multiple stages, and a rolling mill 13 leading to the pinch roll 12 in front of the laying head 11 is shown.
In the meantime, the water cooling device 1 is arranged in multiple stages. The conditions for this multi-stage arrangement are determined by the specifications, dimensions, target quality, etc. of the wire rod to be rolled, and an appropriate cooling capacity is maintained.

Loose wire 1 from raying head 11
After passing through the heat treatment unit 15, the bundle No. 4 is focused by the focusing unit 16 and conveyed to the next adjusting step.

The water cooling device 1 according to the present invention in FIG. 2 is constructed as shown in FIGS. 1 (a) and 1 (b). FIG. 1A is a schematic perspective view showing the structure of the fin 8 of the male fitting element 3 while seeing through a part of the female fitting element 2. FIG. 1B is an explanatory view schematically showing the element of FIG. 1A in a partial cross section. The female fitting element 2 is shown in a sectional view and the male fitting element 3 is shown in a schematic view. There is.

In the case of FIG. 1 (a) and FIG. 1 (b),
The female fitting element 2 is provided on the inlet side with respect to the traveling direction of the wire 14.
An example configured to fit and hold the male fitting element 3 with the male fitting element 3 is shown.

That is, the water cooling pipe 4 is provided with the female fitting element 2 having the cooling water supply hole 5 and the fitting chamber 6 at one end. On the other hand, the male fitting element 3 is provided with a fin 8 that swivels in the same direction on the outer periphery thereof and a hollow guide hole 9. In the figure, the number of fins is 8, and 7 is an inner wall.

The fins 8 of the male fitting element 3 are inserted into the fitting chamber 6 and fitted with the female fitting element 2 in a state where the cooling water 10 does not leak to form the water cooling device 1. ..

In this configuration, it is the shape condition of the fin 8 that influences the cooling capacity, as shown in FIGS. 1 (a) and 1 (b).
A schematic enlarged view is shown. Here, θf; fin angle θs; slit angle ts; slit width.

The cooling capacity can be adjusted by changing θf, θs, ts and the number of fins.

When the physical properties of the cooling water and the supply conditions are constant, the water cooling device 1 according to the present invention has the structure shown in FIGS.
(A) An ideal vortex is generated as in the water model test shown in FIG. 4 (b), and the wire 14 is cooled uniformly.

FIG. 3 shows A of the water model test apparatus 17 of FIG.
-A 'partial cross-sectional view taken along the arrow, Fig. 4 (A) is a schematic cross-sectional view taken along the line BB' in Fig. 1 (B), and Fig. 4 (B) is taken along the line C- in Fig. 3.
It is a C'arrow cross section explanatory drawing.

As shown in these figures, the swirling cooling water 10 having continuous collision points is supplied in the longitudinal direction of the outer peripheral surface of the wire 14 passing through the water cooling device 1. The vortex-shaped cooling water 10 is the vortex-shaped cooling water 10 as shown in FIG.
The wires 14 are supplied one after another in the longitudinal direction of the outer peripheral surface of the wire 14 and have continuous collision points, so that the cooling water 10 that has reached the preceding point is sequentially metabolized, and the necessary cooling capacity can be maintained, so that the wire 14 is uniformly cooled. To be done.

For comparison with FIGS. 9A and 9B, the cooling device 1 of the applicant company of the present invention is selected from the above-mentioned prior arts.
8 (Japanese Patent Publication No. 63-45451, steel rod wire cooling device)
Swirl flow nozzle Figure 9 (a) and direct injection nozzle Figure 9 (b)
6 shows a situation in which the water model testing device 17 shown in FIG. 5 was tried in the same manner as the water cooling device 1 of the present invention.

The swirl flow nozzle of this comparative example is provided with cooling water 19
Is supplied from the slit-shaped nozzle 20 as shown in FIG.
Cooling water 19 sprayed toward the inner wall of the cooling pipe 21 as
Since the swirling cooling water 19 is supplied along the inner wall 22, it is difficult to fill the cooling pipe 21 and a non-contact surface is likely to occur in the longitudinal direction of the outer peripheral surface of the wire 14.

Therefore, it is difficult for the cooling water 19 to obtain a desired cooling capacity, and it is difficult to perform stable uniform cooling. In other words, in the comparative example, since the collision points are discontinuous vortex-like shapes, the outer peripheral surface of the wire 14 is unevenly cooled in the longitudinal direction of the wire 14.
Easily affect the quality of.

Further, the direct injection nozzle of FIG. 9B has a high cooling ability due to the cooling water 19, but the uniform cooling ability is inferior to the swirling flow nozzle.

On the other hand, the cooling method according to the present invention is shown in FIG.
As described above, the eddy current cooling water 10 having continuous collision points in the longitudinal direction of the outer peripheral surface of the wire 14 can be directly jetted and cooled.

FIG. 5 shows a water model testing device 17 for which the method of the present invention has been tried. The guide roller 24, the electric furnace 25, and the guide roller 2 are mounted on the frame 23 in this order from the inlet side of the wire 14.
6, a draining nozzle 27 provided via a compressed air device and a pipe (not shown), a cooling water supply device and a flow meter 28 (not shown), a water cooling device 1 provided via a pressure gauge 29, a guide roller 3
0, a draining nozzle 31 provided through a compressed air device (not shown) and a pipe, a pinch roller 34 rotatably provided through a drive device 32 and a belt 33, an upper thermoviewer 35,
It is composed of a lower thermoviewer 36, a guide rail 37, a waterproof cover 38 surrounding the guide roller 26 to the draining nozzle 31, and is tested by using a sample wire rod 14.

Using this water model testing device 17, a characteristic study on cooling of the water cooling device 1 according to the present invention was conducted. As a result, the results shown in FIGS. 6 to 8 were obtained, and the shape condition of the fin 8 was investigated based on the results. The physical conditions of the cooling water 10 used in this test are shown in Table 1.

[0056]

[Table 1]

FIG. 6 shows the result of examining the fin angle θf. It can be seen that the vortex pitch depends on the fin angle.
Here, the vortex flow pitch is the length of the pitch of one cycle of the vortex in the water cooling pipe measured by a high speed video camera with the tracer 39 inserted.

In FIG. 6, the □-□ line indicates the cooling water flow rate of 300.
The case of liter / min is shown, and the line XX is 400.
The case of liter / min is shown.

The water cooling device 1 of the present invention was constructed by obtaining the optimum conditions in this way, and as a result, it was possible to reduce the temperature unevenness as shown in the graph of FIG. That is, the dotted line in FIG. 7 shows the level when the wire rod sample as the test material is allowed to cool, but the method according to the present invention suppresses the temperature unevenness when the wire rod sample is allowed to cool as shown by the line ◯ − ◯. Recognize.

Further, in FIG. 7, the line □-□ is an example of the swirl flow nozzle of Japanese Examined Patent Publication No. 63-45451 (Nippon Steel) among the above-mentioned prior art examples, and the dimensional conditions are shown in Table 2. ..

[0061]

[Table 2]

As is apparent from FIG. 7, it is understood that temperature unevenness occurs in the system in which the swirl flow nozzle is provided.

Further, in FIG. 7, the line Δ-Δ is one of the prior art examples described above, which is Japanese Patent Publication No. 63-45451 (Nippon Steel).
The direct injection nozzle was tried, and the dimensional conditions are shown in Table 3.

As is apparent from FIG. 7, it is understood that temperature unevenness occurs in the system in which the direct injection nozzle is provided.

[0065]

[Table 3]

Furthermore, as a result of verifying the cooling capacity of the cooling device of the present invention, as shown in the graph of FIG.
It was found that the same cooling water flow rate provided a high cooling capacity. That is, in FIG. 8, the line ◯ − ◯ indicates the heat transfer coefficient representing the cooling capacity of the present invention, and the line □ − □ indicates the direct injection nozzle of Japanese Patent Publication No. 63-45451 (Nippon Steel) of the above-mentioned prior art example. The line Δ-Δ also shows the cooling capacity of a swirl flow nozzle tried in the same manner, but it can be seen that the system according to the present invention has a higher cooling capacity than other cooling devices.

[0067]

INDUSTRIAL APPLICABILITY As described below, the present invention exerts industrially beneficial effects in addition to the above-mentioned initial technical problems aimed at.

According to the present invention, a high cooling capacity can be obtained.

According to the present invention, a high cooling capacity can be stably obtained.

Since the present invention can perform stable and uniform cooling, it is possible to improve the quality of steel bars and wire rods.

In the present invention, the main structure of the water cooling device 1 is such that the female fitting element 2 of the water cooling pipe 4 is fitted with the male fitting element 3 provided with the fins 8. Element 3
Since the shape condition of the fin 8 can be selected by selectively fitting, the cooling condition can be maintained according to the type of the steel bar / wire and the desired quality requirement.

In particular, such a male fitting element 3 and a female fitting element 2
The selection configuration of the appropriate desired cooling conditions by the selective combination of is an inherent effect not found in the above-mentioned prior art examples, and is industrially useful in rolling steel bars and wire rods.

[Brief description of drawings]

FIG. 1 (a) is a schematic perspective view showing a partial perspective view of a water cooling device according to the present invention, and FIG. 1 (b) is FIG. 1 (b).
FIG. 3 is an explanatory view schematically showing a part of the element of FIG.

FIG. 2 is an explanatory diagram showing an example of a wire rod rolling step in which water cooling devices according to the present invention are arranged in multiple stages.

FIG. 3 is a partial cross-sectional explanatory view of the water cooling device according to the present invention shown in FIG. 5, taken along the line AA ′.

4 (a) is a schematic sectional view taken along the line BB ′ of FIG. 1 (b), and FIG. 4 (b) is a sectional view taken along the line CC ′ of FIG. is there.

FIG. 5 is a schematic view of a water cooling device.

FIG. 6 is a graph showing the results of the shape characteristic test of the fin according to the present invention.

FIG. 7 is a graph showing the relationship between temperature variation and cooling water flow rate.

FIG. 8 is a graph showing the relationship between heat transfer coefficient and cooling water flow rate.

FIG. 9 (a) is an explanatory view of a cooling water flow of a swirl flow nozzle in a conventional example, and FIG. 9 (b) is an explanatory view of a cooling water flow of a direct injection nozzle in a conventional example.

[Explanation of symbols]

 1 Water Cooling Device 2 Female Fitting Element 3 Male Fitting Element 4 Water Cooling Pipe 5 Cooling Water Supply Hole 6 Fitting Chamber 7 Inner Wall 8 Fin 9 Guide Hole 10 Cooling Water 11 Raining Head 12 Pinch Roll 13 Rolling Machine 14 Wire Rod 15 Heat Treatment Device 16 Focusing Device 17 Water Model Testing Device 18 Water Cooling Device 19 Cooling Water 20 Slit Nozzle 21 Cooling Pipe 22 Inner Wall 23 Frame 24 Guide Roller 25 Electric Furnace 26 Guide Roller 27 Draining Nozzle 28 Flowmeter 29 Pressure Gauge 30 Guide Roller 31 Draining Nozzle 32 Drive device 33 Belt 34 Pinch roller 35 Upper thermoviewer 36 Lower thermoviewer 37 Guide rail 38 Waterproof cover 39 Tracer θf Fin angle θs Slit angle ts Slit width

Claims (4)

[Claims] 1. A steel bar or wire rod, characterized in that a steel bar or wire rod introduced into a water cooling device is cooled while supplying eddy-like cooling water having continuous collision points from the longitudinal direction of the outer peripheral surface thereof. Water cooling method. 2. The water cooling method for steel bars and wire rods according to claim 1, wherein multi-stage cooling is performed while supplying vortex-like cooling water having continuous collision points. 3. A cooling water supply hole 5 is provided at one end of the water cooling pipe 4.
And a female fitting element 2 having a fitting chamber 6 and a fin 8 that swivels in one direction on the outer periphery of the female fitting element 2 and a male fitting element 3 having a hollow guide hole 9 are formed. A steel bar / wire rod water cooling device, characterized in that the fitting element 3 is fitted to the female fitting element 2. 4. The water cooling device for steel bars and wire rods according to claim 3, wherein the water cooling device 1 formed by fitting the male fitting elements 3 to the female fitting elements 2 is installed in multiple stages on the induction line for the steel bars and wire rods. ..