JP3424157B2 - Method and apparatus for cooling section steel - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for cooling shaped steel, and more specifically, to H-shaped steel, angle steel,
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for cooling a shaped steel, such as a channel steel, which is effective when a cooling surface is erected and cooled.

[0002]

2. Description of the Related Art In recent years, in order to reduce the thickness of H-section steel webs,
Web waves are easily generated in the production line, and cooling of the flange is essential to prevent the generation of such web waves. In cooling the flange for preventing such web waves, in order to prevent the vertical bending over the entire length of the H-section steel after cooling, generally uniform cooling of the flange in the vertical direction or uniform cooling of the upper and lower sides is performed. However, in the cooling of the entire width of the flange, the temperature of the lower portion of the flange tends to be low due to the characteristic that the cooling water flows from the top surface to the bottom surface of the flange (hereinafter referred to as "downflow water").

As a method of adjusting the upper and lower cooling capacities of such a flange, there is an invention described in Japanese Patent Laid-Open No. 1-116033. The present invention adjusts the upper and lower cooling capacities of the flange by moving the nozzle itself that ejects cooling water up and down. For this purpose, a mechanism for vertically moving the nozzle header itself is used. It was necessary, and there was a problem that equipment costs and maintenance costs increased.

As a technique for solving such a problem, Japanese Patent Laying-Open No. 4-284914 and Japanese Patent Publication No. 5-305 have been proposed.
Invention described in Japanese Patent Publication No. 23 (hereinafter referred to as Prior Art 1)
There is. According to the present invention, nozzles are arranged in multiple stages in the vertical direction of the flange of H-section steel, and a spillage influence coefficient in consideration of spillage water is provided. The cooling capacity or the amount of cooling water is adjusted.

The invention described in Japanese Patent Laid-Open No. 5-337535 (hereinafter referred to as "prior art 2") refers to the temperature distribution of the flange before cooling or the temperature distribution of the flange during cooling and refers to the downstream of the rolling line. The cooling device installed on the side controls the upper and lower cooling control of the flange to turn the nozzle on and off.
It was designed to be done by.

[0006]

The invention of the prior art 1 does not take into consideration the change of the boiling state on the cooling surface due to the decrease of the surface temperature of the flange. There is a problem that the controllability of the cooling capacity above and below the flange is poor due to cooling.
Further, in Prior Art 2 as well, it is difficult to control the temperature difference between the upper and lower sides of the flange because the boiling state on the cooling surface due to the decrease in the surface temperature of the flange is not known.

Further, in the multi-stage nozzle arrangements of the prior arts 1 and 2, (1) since the number of nozzles is large, the equipment becomes complicated.
(2) Many flow control valves and control mechanisms are required.
(3) Nozzle ON / OFF when the flange size is different
Since the flow rate fluctuation due to is large, the cooling controllability deteriorates.
There was a problem such as.

Further, as a device for performing uniform cooling for various flange sizes without using a multi-stage nozzle arrangement,
There is a device described in Japanese Utility Model Publication No. 5-93611.
In this invention, the flange outer surface is made to face a vertically standing H-section steel, and a nozzle row for spraying a cooling liquid aligned in the longitudinal direction of the H-section steel is provided, and a guide rail is provided on the flange outer surface of the H-section steel. This is a combination of diagonally arranged spray nozzle rows that can move along this guide rail, and when the flange size is different, move the spray nozzle rows up and down along the guide rails to accommodate them. Further, when the temperature of the flange portion below the web is high, a part of the spray nozzle row is lowered to cool the high temperature portion.

However, since such a cooling device uses a spray nozzle for spraying the cooling liquid in an oblique direction, the lower part of the flange is always cooled even when the spray nozzle row is moved up and down, and the upper part of the flange is cooled. This cannot be dealt with when the temperature has a high temperature distribution. Further, since the lower portion of the flange is always cooled, there are various problems such as further inducing the influence of the spilled water to overcool the lower portion of the flange. As is clear from the above description, there has been no cooling method and cooling device for H-section steel capable of changing the flange size and uniformly cooling the upper and lower sides of the flange by a simple method.

The present invention has been made in order to solve the above-mentioned problems, and corresponds to the change of the flange size of H-section steel or the like, and uniformly cools the upper and lower sides of the flange of H-section steel or the like by a simple method. The object of the present invention is to provide a method and apparatus for cooling a shaped steel capable of preventing the occurrence of vertical bending.

[0011]

(1) In a method for cooling a shaped steel according to the present invention, a spray nozzle is provided with a wide spray nozzle.
Move it diagonally up and down at the same angle as the lower angle
A method for cooling a section steel for cooling a section steel flange, comprising:
The surface temperature of the flange to be removed is 500 ℃ to 650 ℃ or higher.
Oite, as heights of the lower non-cooled portion of the upper uncooled portion of the flange of the section steel is substantially equal, the spool
The range of the direct contact area of the cooling water sprayed from the Reynolds
It was adjusted .

(2) The method for cooling a shaped steel according to the present invention is
The play nozzle is spread and the lower angle of the spray nozzle, etc.
Move the slanted vertical direction at a desired angle to attach the shaped steel flange.
Cooling method for shaped steel that is cooled, and the flange is initially cooled.
When the surface temperature of a part of the flange falls below 500 ° C. to 650 ° C., the cooling water is directly contacted in the vertical direction of the flange every time the cooling process progresses.
The contact area is narrowed.

(3) Further , the method for cooling a shaped steel according to the present invention.
Spread the spray nozzle down the lower angle
Move it diagonally up and down at an angle equal to
A method for cooling a shaped steel for cooling a flange, wherein the entire width of the flange is uniformly cooled at the beginning of cooling, and when the surface temperature of a part of the flange is lower than 500 ° C to 650 ° C, the cooling step is performed. wherein it is by a spray nozzle that to adjust the vertical cooling capacity of the flange.

(4) Further, the cooling device for shaped steel according to the present invention is constructed integrally with the lateral deviation prevention guide, and an inclined surface having an angle equal to the downward spread angle of the spray nozzle is formed on the lateral deviation prevention guide side. Having a carriage that is movable in a direction orthogonal to the section line of the shaped steel, a nozzle header that has a spray nozzle, and is arranged on an inclined surface of the carriage,
It consists cooling device and a driving means for moving along the nozzle header to the inclined surface of the carriage, pressure of the cooling device
Installed on the downstream side of the rolling mill,
Water in the vertical direction of the flange of the shaped steel
The direct contact area of the
Each time you go to the front, the spray nozzle of the cooling device
The cooling capacity in the vertical direction of the flange is higher
It was done so.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The inventors of the present invention have clarified the mechanism of occurrence of supercooling by flowing water as follows. That is, the occurrence of supercooling due to the flowing water depends on the boiling state at the surface temperature (here, the surface temperature of the flange of the H-section steel) of the portion of the material to be cooled (here, the flange of the H-section steel) that is exposed to the cooling water. , Found to be affected.

Generally, when cooling the flange of the H-section steel, the cooling is performed with the flange standing in the vertical direction. Therefore, the cooling water sprayed on the surface of the flange, as shown in FIG. Radially spreads down the surface, and
It falls while making contact with it so that it flows over the flange surface.
Therefore, the cooling water on the flange surface includes direct contact portion A (area A in FIG. 6) where the cooling water sprayed from the nozzle comes into contact with the cooling surface, and the contacting cooling water radially spreads downward to the surface of the flange. Indirect contact portion B flowing in the area (area B in FIG. 6)
Divided into The contact area of the indirect contact portion B becomes wider toward the bottom of the flange.

Further, in the intermediate portion of the direct contact portions A adjacent to each other at the lower portion of the flange, the cooling water that spreads radially and drops collides with the indirect contact portion B by the adjacent nozzles. Area C) exists. Here, the interference area portion C is also considered as the indirect contact portion B, but generally H
The flange cooling device for shaped steel is arranged in combination with the horizontal deviation prevention guide for H-shaped steel, and the presence of this lateral deviation prevention guide causes cooling water to be pushed between the flange and the lateral deviation prevention guide. The area C may be cooled to the same level as or higher than the area of the indirect contact section B due to the surface flow. However, it does not have the cooling capacity as much as the direct contact portion A.

As described above, it was clarified that the indirect contact portion B and the interference area portion C of the falling water existed in the lower portion of the flange in the continuous cooling device, but the flange surface temperature was 500.
When the temperature is higher than 650 ° C., the cooling water in contact with the surface to be cooled immediately becomes steam due to the heat of the surface to be cooled, and a steam film is formed because steam is continuously generated. Does not come into direct contact with the surface to be cooled (this state is called film boiling).

Therefore, since the direct contact portion A has a momentum that impinges on the flange in the vertical direction, the film boiling state can be broken to cool the flange, but the indirect contact portion B (interference region portion C). (Including), there is no momentum that impinges on the flange in the vertical direction, so a complete film boiling state is achieved, and the cooling capacity is considerably lower than that of the direct contact portion A. In this state, the cooling capacity of each part is the largest in the area A, and the areas B and C are almost equal.

However, in a continuous cooling system,
As the cooling process progresses, the surface temperature of the flange decreases, and when the temperature becomes lower than 500 to 600 ° C, the formation of the vapor film weakens and the cooling water comes into direct contact with the surface of the flange, which improves the cooling capacity. (This state is called transition boiling), and cooling progresses in the lower portion of the flange where there are many indirect contact portions B. In particular, since the cooling water is pushed into the interference area portion C, the cooling capacity is further larger than that of the indirect contact portion B. The cooling capacity of each part in this state is (area A)> (area C)>
It is (Region B), and it has been clarified that this is a mechanism of occurrence of supercooling due to falling water.

Generally, H-section steel is cooled during or after rolling, but the flange surface temperature at the start of cooling is 650.
In many cases, the indirect contact parts (regions B and C) are film boiling with a low cooling capacity at the start of cooling, but when the cooling surface temperature decreases, the indirect contact part The (regions B and C) are transition boiling where the cooling capacity is high. Therefore, if the entire width of the flange is cooled in the cooling device of a certain length, the lower part of the flange is overcooled, and conversely, if the lower part of the flange is not cooled in anticipation of flowing water, the surface temperature will be high. Since the indirect contact portions (regions B and C) do not undergo transitional boiling, the temperature at the bottom of the flange becomes high.

From the above, when cooling the flange of the H-section steel by passing it through a cooling device of a certain length,
In order to perform uniform cooling of the upper and lower sides of the flange, (1) full width cooling is performed at the beginning of cooling the flange, and (2) when the surface temperature of a part of the flange falls below 500 to 650 ° C, the lower part of the flange is cooled. If the surface temperature of a part of the flange falls below 500 to 650 ° C., the cooling of the lower part of the flange is strengthened to cool the lower part of the flange at the indirect contact part (region B). , C) to compensate. In addition, the cooling of the indirect contact portion (regions B and C) spreads as the cooling process progresses, so that the above (2)
In the case of 3, the cooling of the lower part of the flange is further weakened or stopped, and in the case of (3) above, the cooling of the upper part of the flange is further strengthened.

As is apparent from the above description, in the present invention, the flange of the H-section steel is cooled, and the entire width is initially cooled, and the surface temperature of a part of the flange during cooling is 50%.
When the temperature drops to 0 to 650 ° C, the cooling of the lower part of the flange is weakened or stopped, or the cooling of the upper part of the flange is strengthened to enable uniform cooling of the upper and lower parts of the flange.
Further, it is intended to prevent the occurrence of shape defects such as vertical bending of the H-section steel.

Experimental Example 1 Height 300 mm, Width 300 mm,
A test piece made of general steel material with a thickness of 20 mm and a surface temperature of 800 ° C was set up on a carrier and fixed, and was placed at intervals of 200 mm (however, the upper uncooled portion 25 mm, the lower uncooled portion 25 m
m) In front of the 6th row of spray nozzles, cooling was performed by reciprocating 6 times at 14 second intervals. The temperature distribution in the vertical direction at the center of the cooling surface was measured with a radiation thermometer. The flow rate of one spray nozzle was set to 60 [l / min].

[0025] As a result, as the cooling proceeds, especially since the surface temperature of 4 reciprocating th from the flange lower portion indirect contact portion B off the 600 ° C., the cooling by a stream of water C becomes transition boiling condition, the flange lower portion It was Tsu name to supercooling.

[Experimental Example 2] As in Experimental Example 1, a height of 30
0mm, width 300mm, thickness 20mm, surface temperature 800 ℃
Stand the test piece consisting of the general steel material of the
Six rows of spray nozzles on the upper side (upper non-cooling portion 25 mm, lower non-cooling portion 75 mm) arranged at intervals of 00 mm were cooled back and forth 6 times at 14-second intervals. In addition, spray nozzle 1
The amount of cooling water of the book was set to 60 [l / min].

The release morphism result of temperature distribution in the vertical direction by Rihiya却面side central thermometer to measure, because it did not completely cooled down portion, the surface temperature even with falling water becomes higher film boiling state, The part was hardly cooled .

[Experimental Example 3] Similar to Experimental Examples 1 and 2, the height was 300 mm, the width was 300 mm, the thickness was 20 mm, and the surface temperature was 80.
A test piece made of a general steel material at 0 ° C. was set up on a carrier and fixed, and six rows of spray nozzles arranged at 200 mm intervals were reciprocated 6 times at 14 second intervals to cool the test piece. The amount of cooling water for one nozzle was 60 [l / min]. In consideration of Experimental Examples 1 and 2, the spray nozzle initially had 3 reciprocations,
Similar to Experimental Example 1, the full width spray nozzle was used for cooling, the nozzle was changed from the fourth reciprocation, and the remaining 3 reciprocations were performed by the upper side spray nozzle which does not cool the lower 75 mm as in Experimental Example 2.
Cooled.

[0029] The release morphism thermometer to measure the temperature portions in the vertical direction of the cooling surface side central. Is cooled to around 600 ° C. at full width cooled below 600 ° C. to effect the falling water comes out, switched to the upper side spray nozzle uncooled portion of the lower large. Therefore, the lower portion of the specimen without being over-cooled, vertical is substantially uniformly cooled.

[First Embodiment] FIG. 1 shows a first embodiment of the present invention.
FIG. 2 is an explanatory view showing an outline of FIG. 2, and FIG. 2 is an explanatory view showing an arrangement example of the cooling device. In both figures, 1 is an H-section steel to be cooled, 2 is a flange, and 3 is a web. Reference numeral 5 denotes a cooling device, which is provided at a rear side (downstream side) of the finish rolling mill 4 along both sides of the H-section steel conveying line 15 for 60 m. The cooling device 5 has a first zone 5a, a second zone 5b, and a third zone 5c at 15 m intervals in the longitudinal direction.
And the fourth zone 5d is divided into four zones.

The cooling device 5 in each of the zones 5a to 5d is constructed integrally with the lateral shift prevention guide 8, has an inclined surface 7 at an angle θ (60 ° in the embodiment) on the side of the conveying line 15, and has a floor surface 17 A drive device 1 provided with a carriage 6 movable above in a direction orthogonal to the transport line 15 (left-right direction), a spray nozzle 10 provided on an inclined surface 7 of the carriage 6, and provided on the carriage 6.
A nozzle header 9 connected to a wire 13 wound around two (both constitute a driving means) is provided. Reference numeral 16 is an H-shaped steel conveying roller.

The spread angle of the spray nozzle 10 is shown in FIG.
As shown in, when the fuel is injected horizontally, the escape angle θ ₁ is 5
°, spread angle θ ₂ is 55 °, spread downward angle θ ₃ is 6 °
It is 0 °. Therefore, the angle θ of the inclined surface 7 of the carriage 6 is set to be equal to the spread downward angle θ ₃ of the spray nozzle 10, and the nozzle header 9 is moved diagonally in the vertical direction along the inclined surface 7 of the carriage 6 so that the flange is constantly 2 lower uncooled part Z ₁ (This height is 0 from the lower end of the flange 2)
(It is constant at about 50 mm) and the upper non-cooling part Z ₂ can be cooled, and when the flange width is changed, the nozzle header 9 can be moved diagonally up and down to accommodate various flange sizes. You can

In moving the nozzle header 9, in the present embodiment, the wire 13 wound around the drive unit 12 is used.
Is carried out by winding up or rewinding. As a result, in the present embodiment, it is possible to accommodate a flange size of 150 mm to 500 mm. Further, in the case of changing the height of the web 3, it can be dealt with by moving the carriage 6 in the left-right direction together with the left-right deviation prevention guide 8.

Spray nozzle 10 in each zone 5a-5d
In consideration of the results of Experimental Examples 1, 2, and 3 described above, when the partial surface temperature of the flange 2 falls below 500 to 650 ° C, the vertical cooling width of the flange 2 can be adjusted. , As shown in FIG. That is, a basic spray nozzle 10a (escape angle θ ₁ : 5 °, spread angle θ ₂ : 55 °, spread downward angle θ ₃ : 60 °) that can cool the entire width of the flange 2 was attached to the first zone 5a. . A spray nozzle 10b having an escape angle θ ₁ : 5 °, a spread angle θ ₂ : 50 °, and a spread downward angle θ ₃ : 55 ° was attached to the second zone 5b.

In the third zone 5c, the clearance angle θ ₁ : 5
°, spread angle θ ₂ : 45 °, spread downward angle θ ₃ : 5
A 0 ° spray nozzle 10c was attached. In addition, in the fourth zone 5d, the clearance angle θ ₁ : 5 ° and the spread angle θ ₂ :
A spray nozzle 10d having a spread angle of 40 ° and a downward spread angle θ ₃ : 45 ° was attached. Therefore, the nozzle arrangement is such that the cooling width is reduced in the upper direction of the flange 2 as the zone advances, and the vertical cooling width of the flange 2 is adjusted.

Next, an example of cooling the flange 2 of the H-section steel 1 according to the present embodiment configured as described above will be described. [Example 1] H-section steel 1 to be cooled has a flange width of 300 m.
3. The web height is 800 mm, the flange thickness is 26 mm, the web thickness is 14 mm, and the length is 30 m.
It was passed at a transport speed of 0 m / s. The upper average surface temperature and the lower average surface temperature of the flange 2 before cooling were 882 ° C. and 885 ° C., respectively, and the temperatures above and below were almost equal. At this time, the uncooled portion Z ₁ below the flange of the first zone 5a is 2
Since it is 0 mm, the height H of the spray nozzle 10 is expressed by the equation (1) shown in FIG. 3 from the bottom surface, that is, H = F−Z ₂ + Z ₃ tan θ ₁ / so that the upper uncooled portion Z ₂ is also 20 mm.
From (tan θ ₃ −tan θ ₁ ), the height was set to 294 mm, and the vertical cooling range of the flange 2 was adjusted. The amount of cooling water was 60 [l / min] per nozzle, and a total of 2160 [t / hr] was injected. This condition is H
Adjust appropriately according to each condition of shaped steel.

As a result of cooling the H-section steel 1 under the above conditions, the upper average surface temperature of the flange 2 after the cooling recuperation is 577 ° C.,
The lower average surface temperature was 575 ° C., and the upper and lower parts of the flange were uniformly cooled. Further, even at room temperature, no shape defect such as bending did not occur. The temperature after the cooling heat recovery is 57
The temperature of the flange surface during cooling is 500 ° C or higher, but 500
It is considered that the temperature is lower than 0 ° C., the boiling state of the above-mentioned indirect contact portion (regions B and C in FIG. 6) is transition boiling, and the influence of the flowing water occurs.

[Embodiment 2] Next, a flange width of 150 mm,
The H-section steel 1 having a web height of 500 mm, a flange thickness of 12 mm, a web thickness of 6 mm, and a length of 50 m was passed through the transport line 15 at a transport speed of about 6.0 m / s. The upper average surface temperature of the flange 2 before cooling was 823 ° C. and the lower average surface temperature thereof was 827 ° C., and the temperatures above and below were almost equal. At this time, the non-cooling portion Z below the flange of the first zone 5a
_{Since 1} is 20 mm, the height H of the spray nozzle 10 is set to 137 mm from the lower surface according to the formula (1) shown in FIG. 3 so that the upper uncooled portion Z ₂ is also 20 mm. The amount of cooling water was 40 [l / min] per nozzle, and a total of 1440 [t / hr].

As a result of cooling the H-section steel 1 under the above conditions, the upper average surface temperature of the flange 2 after the cooling recuperation is 543 ° C.,
The lower average surface temperature was 541 ° C., and the upper and lower parts of the flange were uniformly cooled. Further, even at room temperature, no shape defect such as bending did not occur. In addition, the temperature after cooling recuperation is 5
40 ℃ or more, but the flange surface temperature during cooling is 50
It is below 0 ° C., and it is considered that the boiling state of the above-mentioned indirect contact portion (regions B and C in FIG. 6) is transition boiling, and the influence of the flowing water occurs. Further, even when non-uniform cooling occurs above and below the flange 2, in the present embodiment, uniform cooling can be easily performed by adjusting the spray nozzle height H in the downstream zone.

[Second Embodiment] The present embodiment is the same as the first embodiment.
The spray nozzle 10 has a cooling capacity changed as the zone advances. Therefore, the configuration of the cooling device 5,
The distance between the zones 5a to 5d, the distance between the spray nozzles, etc. are the same as in the first embodiment. In addition, in order to facilitate the description, the spray nozzle is indicated by reference numeral 11 in the present embodiment.

In the present embodiment, when the surface temperature of a part of the flange 2 is lower than 500 to 650 ° C., the spray nozzle is arranged so that the vertical cooling capacity of the flange 2 can be adjusted. It is arranged as shown in. That is, in the first zone 5a, a basic spray nozzle 11a (escape angle θ ₁ : 5 °, spread angle θ ₂ : 55 °, spread downward angle θ that can cool the entire width of the flange 2 and has a uniform water amount distribution 14a in the vertical direction). ₃ : 60 °) was attached. In the second zone 5b, the spray nozzle 11 having a water amount distribution 14b in which the water amount distribution in the upper part is 1.6 times higher than that in the lower part
b (clearance angle θ ₁ : 5 °, spread angle θ ₂ : 55 °, spread downward angle θ ₃ : 60 °) was attached.

In the third zone 5c, a spray nozzle 11c having a water amount distribution 14c in which the water amount distribution in the upper part is 2.3 times higher than that in the lower part (escape angle θ ₁ : 5 °, spread angle θ ₂ : 55)
And a downward spread angle θ ₃ : 60 °) were attached. Also,
In the fourth zone 5d, the water amount distribution in the upper part is 2.8 from the lower part.
A spray nozzle 11d having a water amount distribution 14d that was doubled (escape angle θ ₁ : 5 °, spread angle θ ₂ : 55 °, spread downward angle θ ₃ : 60 °) was attached. Therefore, the nozzle arrangement is such that the cooling capacity of the upper part increases and the cooling capacity of the lower part decreases as the zone advances.

Next, an example of cooling the flange 2 of the H-section steel according to the present embodiment configured as described above will be described. [Example 3] H-section steel 1 to be cooled has a flange width of 200 m.
m, web height 550mm, flange thickness 22mm, web thickness 9mm, length 40m, about 5.0 on the conveyor line 15.
It was passed through at a transportation speed of m / s. The upper average surface temperature of the flange 2 before cooling was 861 ° C. and the lower average surface temperature was 860 ° C., and the temperatures above and below were almost equal. At this time,
The uncooled portion Z ₁ below the flange of the first zone 5a is 20 mm
Therefore, the height H of the spray nozzle 11 is set to 189 mm from the lower surface according to the formula (1) shown in FIG. 3 so that the upper uncooled portion Z ₂ is also 20 mm. The amount of cooling water is jetted at 50 [l / min] per nozzle, 180 in total.
0 [t / hr] was jetted. In addition, this condition is appropriately adjusted according to each condition of the H-section steel.

As a result of cooling the H-section steel 1 under the above conditions, the upper average surface temperature of the flange 2 after the cooling recuperation is 544 ° C.,
The lower average surface temperature was 545 ° C., and the upper and lower parts of the flange were uniformly cooled. Further, even at room temperature, no shape defect such as bending did not occur. In addition, the temperature after cooling recuperation is 5
40 ℃ or more, but the flange surface temperature during cooling is 50
It is below 0 ° C., and it is considered that the boiling state of the above-mentioned indirect contact portion (regions B and C in FIG. 6) is transition boiling, and the influence of the downstream water occurs.

[Embodiment 4] Next, a flange width of 400 mm,
The H-section steel 1 having a web height of 400 mm, a flange thickness of 21 mm, a web thickness of 13 mm and a length of 45 m was passed through the transport line 15 at a transport speed of about 4.0 m / s. The upper average surface temperature of the flange 2 before cooling was 858 ° C. and the lower average surface temperature was 857 ° C., and the temperatures above and below were almost equal.
At this time, the non-cooling portion Z below the flange of the first zone 5a
_{Since 1} is 20 mm, the height H of the spray nozzle 11 is set to a height of 399 mm from the lower surface according to the equation (1) shown in FIG. 3 so that the upper uncooled portion Z ₂ is also 20 mm. The amount of cooling water is 60 [l / min] per nozzle, and 2 at the front.
160 [t / hr] was injected.

As a result of cooling the H-section steel 1 under the above conditions, the upper average surface temperature of the flange 2 after the cooling recuperation is 510 ° C.,
A lower average surface temperature of 511 ° C and uniform cooling of the upper and lower parts of the flange were performed. Further, even at room temperature, no shape defect such as bending did not occur. The temperature of the cooling recuperation is 510
℃ or more, but the flange surface temperature during cooling is 500 ℃
And the above-mentioned indirect contact portion (area B in FIG. 6,
The boiling state of C) is transitional boiling, and it is considered that the influence of the flowing water occurs.

[Comparative Example] A test was conducted by using the cooling device 5 of Embodiment 1 in which only the full-width spray nozzle 10a was attached as a comparative example. Under each condition, as in the first embodiment, the cooling device 5 is installed behind the finish rolling mill 4 and on both sides of the H-section steel conveying line 15 for 60 m. Further, the cooling device 5 is divided into 4 zones at intervals of 15 m in the longitudinal direction. Each zone has spray nozzles 10a arranged at intervals of 200 mm, and one zone has 75 nozzles on one side, 150 nozzles on both sides, and first to fourth zones. A total of 600 zones and full width spray nozzles 10a were attached. The amount of cooling water is 60 [l / min] per nozzle, 2100 in total.
[T / hr] jetted.

In this cooling device 5, a flange width of 300 mm,
A web height of 800 mm, a flange thickness of 26 mm, a web thickness of 14 mm, and a length of about 30 m, H-section steel 1 is transported at a speed of about 4.0 m.
It was passed at a speed of / s. The upper average surface temperature of the flange 2 before cooling is 873 ° C, the lower average surface temperature is 875 ° C.
So, the temperatures above and below were almost equal. After cooling and heat recovery, the flange 2 had an upper average surface temperature of 583 ° C. and a lower average surface temperature of 523 ° C., and the lower portion of the flange was affected by the downstream water. In addition, when the H-section steel 1 is at room temperature, upward bending occurs,
A bend of 290 mm was generated per m. From the above,
As described above, in Embodiment 1, no bending occurred at all, so it was confirmed that the cooling method of the present invention is effective for uniform flange cooling of H-section steel.

In the above description, the case where the H-section steel is cooled according to the present invention has been described. However, the present invention is not limited to this, and a surface to be cooled is set up such as an angle steel or a channel steel. The present invention can be carried out on a steel section to be cooled.

[0050]

(1) The method for cooling a shaped steel according to the present invention comprises:
The surface temperature of the flange to be cooled is 500 ℃ to 650 ℃ or higher.
In the above , in order to make the heights of the upper uncooled portion and the lower uncooled portion of the flange of the shaped steel substantially equal ,
Range of direct contact area of cooling water sprayed from play nozzle
To adjust the, (2) The cooling initially uniformly cool the entire width of the flange, the surface temperature of a portion of the flange 500 ° C. to 650 ° C.
When the temperature falls below the range , the range of the direct contact portion of the cooling water in the vertical direction of the flange is narrowed each time the cooling process progresses, and (3) or the entire width of the flange is uniformly cooled at the beginning of cooling.
However, the surface temperature of a part of the flange is 500 ° C. to 650.
If the temperature falls below ℃,
-Adjust the vertical cooling capacity of the flange by the nozzle.
Since it has been adjusted, it is possible to obtain the following effects.
Wear.

Even for various flange sizes of shaped steel, the flange can be uniformly cooled, and the vertical bending of the shaped steel can be prevented. In addition, the existing cooling device can be used as it is, and the uniform cooling of the flange of the shaped steel can be realized by changing the spray nozzle or simply adjusting the height of the spray nozzle, so a large effect can be obtained with a minimum investment. You can

[0052] Further (4), the cooling device in the form steel according to the present invention is constructed on the left and right displacement preventing guides integral with the inclined surface of the spread downward angle equal angle of the spray nozzles to the left and right displacement preventing guide side a, a carriage movable in a direction perpendicular to the conveying line of the shaped steel has a spray nozzle, a nozzle header which is disposed on the inclined surface of the carriage,
It consists cooling device example Bei and driving means for moving along the nozzle header to the inclined surface of the carriage, pressure of the cooling device
Installed on the downstream side of the rolling mill,
Water in the vertical direction of the flange of the shaped steel
The direct contact area of the
Each time you go to the front, the spray nozzle of the cooling device
The cooling capacity in the vertical direction of the flange is higher
Since it was made to do so, the cooling method of the shaped steel of said (1) -(3) can be implemented reliably, and also said (1) - (3)
The same effect as (3) can be obtained.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an outline of a cooling device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of arrangement of cooling devices in a section steel production line.

FIG. 3 is an explanatory view showing an arrangement example of H-section steel and a spray nozzle.

FIG. 4 is an explanatory diagram showing an arrangement example of spray nozzles according to the first embodiment.

FIG. 5 is an explanatory diagram showing an arrangement example of spray nozzles according to the second embodiment.

FIG. 6 is an explanatory diagram showing a state of jetting and flowing down of cooling water on a flange surface.

[Explanation of symbols]

1 H section steel 2 flange 5 Cooling device 6 dolly 7 slope 8 Left / right misalignment prevention guide 9 nozzle header 10,11 spray nozzle 12 Drive 13 wires 15 Transport line

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B21B 45/02 320

Claims (4)

(57) [Claims] [Claim 1] the scan play nozzle of the spray nozzle wide
Move it diagonally up and down at the same angle as the lower angle
A method for cooling a shaped steel for cooling a shaped steel flange, wherein the surface temperature of the cooled flange is 500 ° C to 650 ° C or higher.
In the above , in order to make the heights of the upper uncooled portion and the lower uncooled portion of the flange of the shaped steel substantially equal ,
Range of direct contact area of cooling water sprayed from play nozzle
A method for cooling a shaped steel, characterized by adjusting . 2. A spray nozzle is provided with a wide spray nozzle.
Move it diagonally up and down at the same angle as the lower angle
A method for cooling a shaped steel, comprising cooling a shaped steel flange, wherein the entire width of the flange is uniformly cooled at the beginning of cooling, and when a surface temperature of a part of the flange falls below 500 ° C to 650 ° C, a cooling step. The vertical direction of the flange
A method for cooling a shaped steel characterized by narrowing the range of the direct contact portion of cooling water . 3. A spray nozzle, wherein the spray nozzle is widened.
Move it diagonally up and down at the same angle as the lower angle
A method for cooling a shaped steel, comprising cooling a shaped steel flange, wherein the entire width of the flange is uniformly cooled at the beginning of cooling, and when a surface temperature of a part of the flange falls below 500 ° C to 650 ° C, a cooling step. the method of cooling that section steel to and adjusting the vertical cooling capacity before <br/> Symbol flange with a spray nozzle each time progresses. 4. is configured to the left or right shift prevention guides integrally,
On the side of the left-right deviation prevention guide, there is a trolley having an inclined surface having an angle equal to the downward spread angle of the spray nozzle, which is movable in a direction orthogonal to the section line of the shaped steel, and a spray nozzle. a nozzle header which is disposed on the inclined surface consists of a cooling device provided with a driving means for shifting <br/> moving along the nozzle header to the inclined surface of the carriage, downstream of the rolling mill with the cooling device Installed on the side, and proceed to the downstream side.
And the vertical direction of the flange of the shaped steel by the cooling device
Narrow Mel so the scope of the direct contact of the cooling water upward in
Or spray the cooling device every time it goes downstream.
Cooling capacity of the flange in the vertical direction by the nozzle
The shaped steel cooling device is characterized in that the upper part is made higher .