JP3117590B2 - Method and apparatus for cooling H-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 an apparatus for controlling the quality of H-section steel by cooling the H-section steel on a hot rolling production line.

[0002]

2. Description of the Related Art Techniques for controlling mechanical properties by heat treatment such as forced cooling during rolling or after rolling of rolled steel have already been put to practical use. For example, various means have been proposed, such as an example applied to a hot-rolled steel sheet disclosed in Japanese Patent Application Laid-Open No. Sho 62-15882, TMCP of a thick plate, and forced cooling of a bar or rail.

In the section steel section, for example,
JP-77-924A proposes a means for cooling a rolled material in which a laminar flow water jet is applied to a vertical portion of a rolled steel and a partially laminar water jet and a partial water layer are applied to a horizontal portion. I have. U.S. Pat. No. 4,120,455 discloses means for cooling the inner and outer surfaces of an I-shaped steel flange in an H position by a cooling device comprising a nozzle for injecting a gas-liquid mixture. Regarding forced cooling of H-section steel,
In addition to the purpose of controlling the mechanical properties, a technique of water cooling only the outer surface of the vertical flange to reduce residual stress caused by uneven cooling is disclosed in Japanese Patent Application Laid-Open No. Sho 62-174326. Examples are known. Spray cooling is often used for water cooling in these conventional means. However, of the inner surface cooling, there is an example of spray cooling for the lower part cooling for the purpose of preventing bending and web warpage,
As for the cooling of the upper part, a cooling method of the above-mentioned laminar water jet and gas-liquid mixing is adopted, and a method using spray cooling is not adopted. When cooling the inner surface of the upper flange or cooling the web, the cooling water accumulates on the upper surface of the web to form a pool, and so-called pool cooling is mixed. As described above, a method of supplying a laminar jet from a cooling box as a means of controlling mechanical properties by simultaneous cooling of the inner and outer surfaces of the flange of the H-section steel or simultaneous cooling of the inner and outer surfaces of the flange and the upper and lower surfaces of the web, It is the prior art to spray the mixture.

[0004]

As described above, when the purpose of cooling is to control the mechanical properties or control the residual stress, the cooling of the upper and lower portions of the outer surface and inner surface of the flange is performed by laminar jet or cooling. Alternatively, a gas-liquid mixture is used. When a spray is used, cooling water is injected to the inner surface of the flange or / and the intersection (hereinafter referred to as a fillet) of the flange and the web, and water on the web is sucked and removed before spreading on the web. In the above-mentioned Japanese Patent Application Laid-Open No. 60-77924, which uses a laminar jet, a large number of holes are formed in a cooling box, and cooling water is injected from the holes into the surface to be cooled in a laminar flow state, that is, a bottom flow velocity. However, the space between the cooling box and the surface to be cooled needs to be as small as 10 to 20 mm. For this reason, the rolled material collides with or contacts the cooling box between the cooling box arranged symmetrically for cooling the outer surface of the flange and the inner wall of the flange and the cooling box arranged above and below the web for cooling the web. A strong guide is required to pass without any trouble. By the way, the maximum distance between the cooling box and the surface to be cooled is 20m
m should be set to 10 mm in consideration of the vertical and horizontal contact during running of the rolled material.
The rolled material has warpage not only in the horizontal direction in the rolling posture but also in the vertical direction. Particularly, the unsteady portions at the leading end and the rear end of the rolled material have a large bend. It is difficult to avoid collision or contact of the box. When the cooling box and the rolled material come into contact with each other, the orifice provided in the box is deformed or crushed so that desired cooling cannot be obtained, and the box may be broken. In addition, the method using the gas-liquid mixture requires both gas and liquid supply equipment and piping, and the header and nozzle structures are complicated, and the equipment cost is high.

The present invention provides a simple cooling method for only a liquid,
Another object of the present invention is to provide a cooling method and apparatus for preventing a rolled material from colliding or contacting a cooling facility, particularly for controlling mechanical properties.

[0006]

According to the present invention, there is provided a method and apparatus for cooling the inner and outer surfaces of a flange and the upper and lower surfaces of a web by using a turbulent jet. The gist of the method is as follows.

(1) A method of cooling an H-section steel during or after hot rolling, or after hot rolling or after rolling, while being placed in an H position or during horizontal transfer. A method for cooling an H-section steel, wherein a turbulent water jet is jetted to an upper concave portion of the H-shaped steel to form a water pool, and a turbulent water jet is jetted to a lower concave portion and an outer surface of a flange to cool the H-shaped steel.

(2) The cooling amount of the turbulent water jet and the cooling time or the injection amount and the cooling time are set to be larger in the lower concave portion than in the upper concave portion of the H-section steel and cooled. Method of cooling H-section steel.

(3) The method for cooling an H-section steel according to the above (1) or (2), wherein the H-section steel is cooled while being reciprocated in a horizontal direction.

(4) The above item (1), (2) or (3) wherein the cooling water amount of the turbulent spray in the upper concave portion of the H-section steel is changed according to the temperature distribution in the cross section of the H-section steel. The method for cooling an H-section steel as described above.

(5) An upper cooling device having a spray nozzle in a cooling header divided into two parts movably in the height direction of the web of the H-section steel inside the upper concave portion of the H-section steel, and spray nozzles in left and right side guides. A cooling device for cooling the lower concave portion of the H-shaped steel provided below the conveying surface of the conveying roller, and a cooling water flow preventing front and rear surfaces of the cooling header. A cooling device for H-section steel provided with a water stop mechanism.

(6) The cooling device for an H-section steel according to the above (5), wherein the lower spray nozzle is divided into two parts so as to be movable in the height direction of the H-section steel web.

(7) The above (5) or (6), wherein the spray nozzle zone for cooling the lower concave portion is provided longer than the cooling zone length of the cooling header provided inside the upper concave portion of the H-section steel. H-beam cooling system.

[0014]

The present invention will be described below in detail with reference to the drawings.

FIG. 2 is a schematic plan view showing a process for carrying out the method of the present invention, and is not shown before the rough rolling process. In the drawing, after the material to be cooled 1 is rolled by an intermediate universal rolling mill U and an edger E, it is finally rolled by a finishing rolling mill F, and moves to the direction of arrow A in the stage where the outer flange cooling device 4 and the upper flange are moved. The cooling is performed by the inner surface and web upper surface cooling device 5 and the lower flange inner surface and web lower surface cooling device 6. However, in the case of performing severe forced cooling, not only in one direction during the finish rolling, but also after passing through the cooling device while forcibly cooling it, the roll of the finishing mill F is released, and a predetermined cooling is obtained. Can be reciprocated repeatedly until it is

FIG. 1 is a view showing an apparatus according to an embodiment of the present invention, and shows a cross-sectional state of a material to be cooled 1 being cooled by cooling devices 4, 5, and 6.
Spray nozzles 4a for jetting a turbulent jet are arranged in multiple stages in the flange outer surface cooling device 4, and the number of stages to be used can be set according to the flange width of the coolant 1 to be cooled. This cooling device is incorporated in the side guide 7 for guiding the material to be cooled, and even when the size of the material to be rolled 1 is different, the distance d1 between the nozzle 4a and the outer surface 2a of the flange 2 can be adjusted by adjusting the position of the side guide. It is. The distance d2 between the side guide 7 and the outer surface of the flange is generally set to 20 to 30 mm because of the bending of the material to be cooled. 10m on side guide 7 every few meters
It is effective to attach it by protruding m to 20 mm.
Existing technology can be applied to the forced cooling by the turbulent jet jetted from the nozzle 4a. Upper inner surface 2 of left and right flanges 2
In the present invention, the recess formed by the upper surface 3a of the web 3 and the upper surface 3a of the web 3 is simply referred to as an upper recess. This is performed by injecting a turbulent jet from 5a, 5b, 5c. Here, each of the spray nozzles 5a, 5b, 5c is a flange inner surface 2
b, an example directed to the intersection 2c of the flange and the web and the web upper surface 3a. However, the jet nozzle 5c of the turbulent jet onto the upper surface of the web is not necessarily required for a material to be cooled whose thickness is smaller than the thickness of the flange 2 so that the cooling proceeds quickly. Conversely, for a portion that needs to be cooled strongly, such as the intersection 2c between the flange and the web, a nozzle having a large amount of sprayed water may be used or the nozzles may be densely arranged. In the case of cooling by a laminar jet in the prior art, the distances d3 and d4 between the flange inner surface 2b and the web upper surface 3a of the coolant 1 and the upper inner surface cooling header 51 need to be 10 to 20 mm. When using a spray nozzle, this distance d
1 and d2 have sufficient cooling capacity even if they are 50 mm or more,
Therefore, contact between the cooling material and the header in the transfer of the cooling material can be prevented.

Next, the concave portion formed by the lower inner surface 2d of the left and right flanges 2 and the lower surface 3b of the web 3 is simply referred to as a lower concave portion in the present invention, and the lower concave portion is cooled by the lower cooling header 61. The turbulent jet is jetted from the attached nozzles 6a and 6b. By mounting the header 61 and the nozzles 6a, 6b below the upper surface 8 of the transport roller table, it is possible to prevent contact and collision with the coolant. With regard to the arrangement of the nozzles 6a and 6b, when cooling the flange inner surface 2d in a portion to be particularly strongly cooled, for example, a flange having a large thickness in comparison with the thickness of the web 3, the amount of water jetted by the nozzle 2a for cooling the flange is reduced by the web. May be made larger than the injection water amount of the nozzle 6b for cooling the nozzle, or the nozzles may be densely arranged. When it is necessary to particularly intensify the surface 2e at the intersection of the flange 2 and the web 3, the jet region of the turbulent jet jetted by the flange cooling nozzle 6a and the turbulent jet jetted by the web cooling nozzle 6b are set. Cooling can be enhanced by partially overlapping. The number of rows of nozzles for cooling the inner surface of the flange and the number of nozzles for cooling the web may be set for the lower cooling nozzle in accordance with the size of the area for spraying water and the strength of partial cooling.
By arranging the cooling header and nozzle of the lower recess below the upper surface of the cooling material transport roller table, even if the cooling material is bent downward, contact between the header and the nozzle and the cooling material is prevented. And collision can be prevented.

As described above, since the cooling method is different between the upper concave portion and the lower concave portion, there is a difference in the cooling characteristics between the upper and lower portions. However, by grasping the difference in the cooling characteristics, it is possible to prevent a problem relating to uneven cooling. Is possible. Fig. 3 shows the measurement of temperature change by attaching thermocouples at a depth of 2mm from the inner surface of the upper and lower flanges and at a depth of 2mm from the upper and lower surfaces of the web in order to grasp the difference in cooling characteristics between the upper and lower recesses. The cooling rate is calculated and graphed. The size of the material to be cooled is H538 × 447 × 60 × 9
0 (web height x flange width x web thickness x flange thickness)
As shown in FIG. 4, a flange water cooling nozzle 11a, a fillet cooling nozzle 11b,
A flange cooling nozzle 12a, a fillet portion cooling nozzle 12b, and a web cooling nozzle 12c are arranged on the web cooling nozzle 11c and the lower header 12.

As representative points of temperature measurement, 13a and 14a are used for the upper flange, and 13a and 14a are used for the lower flange.
b and 14b were selected for each two points. The temperature measuring points 13a and 13b and the temperature measuring points 14a and 14b are vertically symmetrical with respect to the center line 17 of the web thickness.
As a representative point for measuring the temperature of the web, 15
a and 16a, and two points each of 15b and 16b were selected for the lower surface. Among them, 15a and 15b are also 16a
And 16b are vertically symmetrical with respect to the web thickness center line. Of the two temperature measurement points on the inner surface of the upper flange, one point 14a is a portion where the turbulent jet is directly jetted from the nozzle 11a for cooling the inner surface of the flange, and one point 13a is not directly subjected to the jet of the turbulent jet, but the pool-like water Is a part where cooling is promoted by the turbulent jet.
On the other hand, of the two temperature measuring points on the inner surface of the lower flange, one point 14b receives a turbulent jet directly from the flange cooling nozzle 12a, and the other point 13b is a turbulent jet from both the flange cooling nozzle 12a and the web cooling nozzle 12b. This is the part that is cooled by the water of the jet flowing down.

One point 15 of the temperature measurement points on the upper surface of the web
a is a portion where the turbulent jet is directly injected from the fillet cooling nozzle 11b, and another point 16a is a central portion in the web width direction, where the turbulent jets injected from the two rows of web cooling nozzles 11c slightly overlap. It is.
One of the temperature measurement points 15b on the lower surface of the web is a portion where both the web cooling nozzle 12b and the turbulent jet jetted from the flange cooling nozzle 12a intersect, and the other point is a web cooling nozzle 12b at the center in the web width direction. This is the part that receives the turbulent jet directly from. Where 15a and 15
b, 16a and 16b are vertically symmetrical with respect to the web thickness center line.

As described above, the temperature measuring points are vertically symmetrical, but the cooling at each symmetrical point is completely different between the upper and lower sides.

In FIG. 3, the horizontal axis is the cooling water density,
The distribution of the turbulent jet jet from the nozzle in the flange width direction and the web width direction is averaged over the entire length of the cooling zone. The vertical axis is the average cooling rate between 800 and 500 ° C. calculated from the temperature measurement data. FIG. 3 (a)
As a feature of the flange cooling, there is no significant difference between the upper flange 14a which receives the direct turbulent jet injection and the position 13a which does not receive the direct injection strongly. This is because the distance between the header 11 and the inner surface of the flange is large, so that pool-like water is widely stirred. Therefore, in spite of the sparse nozzle arrangement, cooling can be accelerated as a whole by increasing the amount of water injected from the nozzles, while cooling is somewhat affected by the intensity of injection. For the lower flange, two temperature measurement points 13b, 14
In comparison with b, although the heat transfer coefficient at the point 14b which receives the turbulent jet more strongly is large and the cooling is quick, there is no particular difference, and a large amount of water may be injected to a portion requiring strong cooling.

When the upper and lower flanges are compared, the average cooling rate of the upper portion is large for the same water density, and the average cooling rate is also sensitive to changes in the water density. However, since the upper and lower heat transfer coefficient levels do not differ greatly, in actual cooling, the upper and lower cooling can be easily balanced by setting a difference in the amount of cooling water used in the upper and lower parts.

FIG. 3 (b) shows the web, where the average cooling rate at the top is much higher than at the bottom. The data of the water density 0 at the upper part jets a turbulent jet from the nozzle 11a for cooling the flange and the nozzle 11b for cooling the fillet portion.
This is a case where cooling is performed by pool-like cooling water without using 6a. That is, the upper surface of the web exhibits a large heat transfer coefficient without jetting the turbulent jet. As described above, since the difference in cooling between the upper surface and the lower surface of the web affects the shape during and after cooling, to balance the cooling of the upper and lower surfaces, not only the difference between the upper and lower cooling water amounts but also the length of the lower cooling zone is made longer than that of the upper portion. It is effective to do. Similarly, it is effective to use the difference between the lengths of the upper and lower cooling zones for the vertical balance of the cooling of the inner surface of the flange.

In addition, H-shaped steels have many web heights and flange widths different from each other, and if the upper inner cooling header and the lower inner cooling header are exchanged every time the rolling size changes, it takes time and manpower. It is convenient to use a variable header structure that can respond to size changes. FIG. 5 shows a variable width mechanism of the upper recess cooling header in the web width direction.
The upper headers 21a and 21b are divided, and the material to be cooled H-section steel 1
The width d of the header 2 is adjusted according to the web height u, and the distance d3 between the inner surface 2b of the flange 2 and the headers 21a and 21b is adjusted.
The distance d4 between the upper surface 3a of the web 3 and the headers 21a and 21b is adjusted according to the flange width F. Adjustment of the distance d3 between the inner surface 2b of the flange and the headers 21a and 21b is performed by using two rotatable screws 23 and 24, which are restrained from moving laterally by a metal fitting 22 attached to a suspension device of the headers 21a and 21b, at their ends. Gears 24 and 25 on the same axis
, And one of them, for example, the gear 24 is rotated by the gear 26 rotated by the electric motor 28 so that the metal fittings 2 for suspending the headers 21a and 21b are provided.
7a and 27b are moved in directions opposite to each other. Headers 21a and 21b and web upper surface 3a
Is adjusted by a mechanism for changing the vertical position of the bracket 22 of the suspension device.

FIG. 6 shows a method of adjusting the position of the header when three headers for cooling the lower inner surface are used. Header 31a,
31b is for cooling the lower inner surface 2d of the flange 2 and the fillet portion 2e, and the header 32 is for cooling the lower surface 3b and the fillet portion 2e of the web 3, and has a horizontal feed mechanism and a vertical position variable mechanism (not shown) for each header individually. When the size of the H-section steel 1 having the web width u and the flange piece width Fi changes from the cooling of the H-section steel 1 having the web width U 'and the flange piece width Fi' to the H-section steel 1 ', the header for cooling the inner surface of the flange. The positions of 31a and 31b are changed by a horizontal feed function and a vertical position variable mechanism, and the web lower surface cooling header 32 is changed.
Can be adjusted so that the turbulent jet suitably collides with the material to be cooled by changing the position of the turbulent jet.

Next, the setting of the cooling water injection amount will be described. In the case of lower inner surface cooling, as shown in FIGS. 4 and 6, when a header is provided for each injection target position, the flow rate can be arbitrarily set in each header. It is. In the case of cooling the upper inner surface, as shown in FIG. 7, a header 41 is attached to the inside thereof and partitioning plates 42, 43, 44 are attached thereto, thereby cooling the flange inner surface 2b, the fillet 2c portion cooling header 46, and the web upper surface 3a. By dividing the header into individual headers 47 and individually setting the flow rate to each of the divided headers.
Cooling control for each cooling part according to the size of the material to be cooled can be performed.

As for the control of the turbulent jet injection position on the inner surface of the upper flange when the width of the flange is changed, the header for cooling the upper inner surface 2b is vertically arranged as shown in FIG. Part 2
c is divided into 52c for cooling, and one of the headers, for example, 51a is provided with a vertical position variable function and a web width direction position variable function in the same manner as in FIG. What is necessary is just to provide a function to change the vertical position. In this case, when the header 52a is divided by the partition plate 53, the nozzles 5a,
The cooling water flow rate can be individually set for 5b and 5c.

There are various sizes of the H-section steel having different thickness ratios of the flange and the web, and it is important to balance the cooling of the two, and as a method for controlling the degree of cooling to the outer surface of the flange is effective. is there. As one of the means, a method shown in FIG. 9 can be applied separately from a method of changing the cooling water amount density according to the size of the material to be cooled. FIG. 9 is a horizontal schematic view of the cooling zone, and includes 61, 62 and 63.
Denotes an upper inner cooling device, a lower inner cooling device, and a flange outer cooling device, respectively. In this example, the upper and lower cooling balance is adjusted by making the lower cooling zone length L2 longer than the upper cooling zone length L1 due to the characteristic difference between the upper cooling and the lower cooling. The cooling zone length L3 on the outer surface of the flange is
Since there are many sizes in which the flange plate thickness is larger than the web plate thickness, a short zone 63 that is larger than the upper and lower cooling zones and that can be arbitrarily selected for use in the length direction of the entire zone is used.
-1 to 63-N and for many sizes where the flange needs to be cooled strongly against the web, use many of the divided short zones for cooling and reduce the cooling of the flange to the web. Conversely, for the size that needs to be done, the use of short zones may be reduced. As the material to be cooled passes through the cooling device having such a cooling zone in the direction of the arrow, the cooling time difference is set depending on the portion in the cross section, and the overall cooling balance can be adjusted. Similarly, the inner upper cooling device 6
1, the lower cooling device 62 is also divided in the length direction,
It is also effective to determine the number of flanges and webs to be used according to their cooling strength requirements. However, by dividing only the outer surface cooling device 63 described above, the cooling strength difference between the flange and the web can be set, and the cooling strength of the entire cooling target can be adjusted by adjusting the feed speed of the cooling target. The lengthwise division of the internal cooling device is not practically necessary.

FIG. 10 shows an example of the prevention of flow 3 in the longitudinal direction of the cooling water in cooling the upper concave portion. Coolant H
The upper and lower water cooling headers 5 in which the flange inner surface cooling nozzles 5a, the fillet portion cooling nozzles 5b, and the web cooling nozzles (not shown) are installed at the upper part of the section steel 1 are provided so as not to impede the passage of the material to be cooled during water cooling. Weirs 61 and 62 that are not in contact with the coolant are arranged. Non-contact water outflow prevention
It is possible to provide a slit 63 on the cooling water pool side in each of the slits 1 and 62 so that a gas such as air is ejected from the slit. FIG. 11 is a longitudinal sectional view showing details of the weir 62.

The weir 62 is provided in the space surrounded by the upper surface 3 a of the web 3 of the H-section steel 1 and the flange 2,
4 and an air passage forming block 65 are opposed to each other. The air delivery block 64 has an air supply pipe 66 for supplying air from a side (hereinafter, a rear side) opposite to a pool side (hereinafter, a front side) of the cooling water. Air passages 67 that are connected and that direct air flow toward the front surface are formed as gaps (slits) with the air passage forming block on the left, right, and lower sides of the front surface of the block.
A concave air pocket is formed on the front surface of the air delivery block 64. The air delivery block 64 and the air passage forming block 65 are connected by bolts 68, and a spacer 69 fitted on the bolt 68 is provided to adjust the gap of the slit 67. Air delivery block 6
A gasket member 70 is interposed above the opposite surface of the air passage forming block 65 and the air passage forming block 65 so that air is not scattered. It is optional whether this dam is connected to the upper cooling header or not.

As described above, the cooling method and apparatus according to the present invention can be installed not only on the exit side of the finishing mill but also at positions 7 and 8 before and after the intermediate rolling mill shown in FIG. It is optional to install at a position 9 in front of the rolling mill and to provide preliminary cooling for cooling after finish rolling. Also, H
It is also optional to use the cooling device for the outer surface of the flange and the cooling device for the inner surface separately according to the size of the steel shape.

[0033]

[Example] Size H918 x 303 x 19 x 37 (web height x flange width x web thickness x flange thickness), steel type S
After the finish rolling of the H-section steel of S400, the inner and outer surfaces were water-cooled. The water cooling equipment and the water cooling conditions are as shown in Table 1.

Since the flange thickness is larger than the web thickness, the equipment for cooling the flange more strongly than the cooling of the web and the cooling water flow density are set. Regarding the inner surface cooling, the length of the cooling equipment at the lower part is made longer than that at the upper part, and the vertical cooling is made uniform. In addition, the upper and lower surfaces of the web are balanced by spraying no water on the upper surface, and therefore cooling the pool by turbulent jets on the lower portion for pool cooling with weak stirring. The cooling water volume density of the inner surface is larger in the upper part than in the lower part in both the flange and the fillet, but the upper and lower cooling strengths are almost equal due to the equipment length.

[0035]

[Table 1]

Table 2 shows the tensile test values of representative portions. The tensile strength and the yield point could be increased without reducing the ductility. In this example, it is possible to manufacture a steel grade of 490 N / mm ² using a steel grade of 400 N / mm ² . That is, low carbon equivalent can be achieved for steel types of the same standard, and it becomes possible to manufacture H-shaped steel products having excellent weldability and toughness.

[0037]

[Table 2]

[0038]

The temperature control from the inner and outer surfaces becomes possible by adding cooling means using turbulent jets of different types to the inner and lower surfaces of the flange and the upper and lower surfaces of the web to the conventionally used outer surface cooling means of the flange. Was. According to the present invention, even when bending occurs during rolling, it is possible to prevent collision between the cooling device and the material to be cooled, and it is possible to eliminate the problem of material property differences in the thickness direction particularly when cooling only from the outer surface of the flange, and to control the material of the web. Is also possible.

[Brief description of the drawings]

FIG. 1 is a schematic front sectional view of the apparatus of the present invention.

FIG. 2 is a schematic plan view of an H-beam rolling process for implementing the present invention.

FIG. 3 is a graph showing a relationship between a cooling rate and a cooling average water density.

FIG. 4 is a schematic front sectional view showing an embodiment of the apparatus of the present invention.

FIG. 5 is a schematic sectional view showing a variable width mechanism of a cooling header of the device of the present invention.

FIG. 6 is a schematic front view showing an embodiment of the lower recess cooling of the present invention.

FIG. 7 is a partial schematic diagram illustrating an embodiment of the cooling header of the present invention.

FIG. 8 is a partial schematic diagram illustrating an embodiment of a cooling header of the present invention.

FIG. 9 is a schematic plan view of an apparatus for controlling a cooling zone length according to the present invention.

FIG. 10 is a partial cross-sectional side schematic view showing a cooling water outflow prevention mechanism in an upper concave portion of the H-section steel.

FIG. 11 is a schematic partial sectional view of the weir of FIG. 10;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cooled material (H-shaped steel) 4 ... Flange outer surface cooling device 5 ... Web upper surface cooling device 6 ... Web lower surface cooling device 7 ... Side guide 51 ... Web upper surface cooling device header 61 ... Web lower surface cooling device header 5a, 5b, 5c: spray nozzle 6a, 6b, 6c: spray nozzle

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroatsu Kato 20-1 Shintomi, Futtsu City Nippon Steel Corporation Technology Development Division (72) Inventor Takefumi Suzuki 20-1 Shintomi, Futtsu City Nippon Steel Corporation Inside the Technology Development Division (72) Inventor Tadayuki Ito 20-1 Shintomi, Futtsu City Nippon Steel Corporation Technology Development Division (56) References JP-A-6-79333 (JP, A) JP-A-5-285522 ( JP, A) JP-A-62-54519 (JP, A) JP-A-53-43008 (JP, A) JP-A-51-63311 (JP, A) JP-A-60-77924 (JP, A) 62-174326 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B21B 45/02 320 C21D 9/00 102

Claims (7)

(57) [Claims] 1. A method of cooling an H-section steel during hot rolling and after rolling, or during hot rolling or after rolling, while being placed in an H position or during horizontal transfer. A turbulent water jet is injected into the upper concave portion of the H-shaped steel to form a water pool, and a turbulent water jet is injected into the lower concave portion and the outer surface of the flange to cool the H-shaped steel. Method. 2. The method according to claim 1, wherein the injection amount and the cooling time of the turbulent water jet, or the injection amount and the cooling time, are cooled by making the lower recess larger than the upper recess of the H-section steel. 2. The method for cooling an H-section steel according to item 1. 3. The method for cooling an H-beam according to claim 1, wherein the H-beam is cooled while being reciprocated in a horizontal direction. 4. The H according to claim 1, wherein the cooling water amount of the turbulent spray in the upper concave portion of the H-section steel is changed according to the temperature distribution in the cross section of the H-section steel.
Cooling method for section steel. 5. An upper cooling device having a spray nozzle in a cooling header divided into two parts movably in the height direction of the web of the H-section steel inside an upper concave portion of the H-section steel, and a spray nozzle in left and right side guides. A flange outer surface cooling device provided, a lower spray cooling device for cooling a lower concave portion of an H-shaped steel provided below a conveying surface of a conveying roller, and a stop for preventing a flow of cooling water on front and rear surfaces of the cooling header. A cooling device for an H-section steel, comprising a water mechanism. 6. The cooling device for an H-section steel according to claim 5, wherein the lower spray nozzle is divided into two parts so as to be movable in the height direction of the H-section steel web. 7. The spray nozzle zone for cooling the lower recess portion is provided longer than the cooling zone length of the cooling header provided inside the upper recess portion of the H-section steel. The cooling device for the H-section steel according to the above.