KR20110029183A - Cooling device in t-bar hot-rolling line, and t-bar manufacturing facility and manufacturing method - Google Patents

Abstract

A cooling device (8) of a T-shaped steel hot rolling line that can minimize the cooling warpage caused by the temperature difference between the flange and the web, and comprises a web (21) having a substantially T-shaped cross section (21) and a flange (22). The outer surface water cooling nozzle 8a which cools the flange outer surface of the to-be-rolled material H by water cooling, and / or the inner surface water cooling nozzle which cools the flange inner surface of a to-be-rolled material by water cooling is provided. The outer surface water cooling nozzle and / or the inner surface water cooling nozzle are of substantially the same height as the leading edge of the web and the lower end of the flange from the substantially horizontal state with respect to the roller table 13 on which the web of the rolled material carries the rolled material. In the case where it is inclined to the state, in any inclined state of the web, it is provided in the position and direction which can be watered toward the outer surface and / or inner surface of a flange.

Description

Cooling device of T-beam hot rolling line, T-steel manufacturing equipment and manufacturing method {COOLING DEVICE IN T-BAR HOT-ROLLING LINE, AND T-BAR MANUFACTURING FACILITY AND MANUFACTURING METHOD}

The present invention relates to a cooling device, a manufacturing facility, and a manufacturing method for producing a T-bar (T-bar) by hot rolling.

The cross-sectional shape of T-shaped steel is shown in FIG. The T-shaped steel 20 is a T-shaped cross section consisting of a web 21 and a flange 22, and is widely used in fields such as shipbuilding and bridges. T-shaped steels are manufactured in various sizes according to their use, conditions of use, locations of use, and the like. Commonly used T-shaped steel 20 has a web height of about 200 to 1000 mm, a web thickness of about 8 to 25 mm, a web internal dimension of about 190 to 980 mm, and a flange width of about 80 to 400 mm. Flange thickness: about 12-40 mm. Moreover, in the case of the T-shaped steel 20 used for shipbuilding, the web height is often more than twice the width of the flange.

Although the T-shaped steel 20 is generally manufactured by welding the web 21 and the flange 22, the technique of integrally forming by hot rolling is also proposed.

For example, in order to efficiently produce hot rolled T-shaped steel having various dimensions of web thickness, flange thickness, web height, and flange width, a universal mill is used in the intermediate rolling and finishing rolling processes. Arranged hot rolling equipment is proposed (for example, refer patent document 1). An example of a hot rolling facility is shown in FIG.

This hot rolling facility 101 is a priming molding mill 102 which reciprocally rolls a raw material steel piece carried out from a heating furnace (not shown), and primings it into a roughly T-shaped cross section, and this priming molding mill ( The intermediate rolling mill group 103 for forming a T-shaped steel piece (see Fig. 14) first formed into a roughly T-shape by a 102) into a T-shaped steel having an approximately product dimension, and a T-shaped steel molded to an approximately product dimension The finishing universal rolling mill 106 is formed. The intermediate rolling mill group 103 is provided with the edge mill 105 which was provided downstream of the primary universal rolling mill 104 and the primary universal rolling mill 104. As shown in FIG.

The rolling process by the primary molding rolling mill 102 is a primary molding rolling process, and the structure of the primary molding rolling mill 102 is shown schematically in FIG. 13 (A). The primary molding rolling mill 102 is provided with an upper roll 102a and a lower roll 102b in which three sets of balls are formed. Then, the primary molding rolling mill 102 sequentially rolls the raw material steel pieces in the form of these balls to form a rolled material (T-shaped steel piece) H composed of the web 21 and the flange 22 shown in FIG. 14. To get

In addition, the rolling process by the primary universal rolling mill 104 and the edge rolling mill 105 which comprises the intermediate rolling mill group 103 is an intermediate rolling process, The structure of the primary universal rolling mill 104 is shown to FIG. 13 (B). The structure of the edge mill 105 is shown typically at 13 (C). The primary universal rolling mill 104 is provided with a pair of horizontal rolls 141a and 141b and a pair of vertical rolls 142a and 142b as shown in Fig. 13B. As shown in FIG. 13 (C), the edge mill 105 has a pair of edge rolls 151a and 151b each having a large diameter roll portion 153 and a small diameter roll portion 154. Have The rolled material (T-shaped steel piece) H obtained in the primary molding rolling process includes the primary universal rolling mill 104 and the edge rolling mill 105 constituting the intermediate rolling mill group 103 provided on the downstream side of the initial molding rolling mill 102. As a result, the thickness of the web 21 and the flange 22 is reduced, and the width of the flange 22 of the flange 22 is adjusted to a rolled material (T-shaped steel of approximately product dimension) H. At this time, by adjusting the roll gap of the horizontal rolls 141a and 141b, it is possible to adjust to various web thicknesses without performing roll exchange, and also by adjusting the roll opening degree of the vertical roll 142a to obtain various flange thicknesses. Can be adjusted. In addition, the flange width can be adjusted by adjusting the distance between the small-diameter roll portions 154 of the pair of edger rolls 151a and 151b.

In addition, the rolling process by the finishing universal rolling mill 106 is a finishing rolling process, and the structure of the finishing universal rolling mill is shown typically in FIG.13 (D). The finishing universal rolling mill 106 is equipped with a pair of horizontal rolls 161a and 161b and a pair of vertical rolls 162a and 162b, as shown to FIG. 13 (D). And as for the to-be-rolled material H obtained by the intermediate rolling process, the flange 22 stands up vertically by the finishing universal rolling mill 106, and becomes a product cross-sectional shape.

By the way, in the hot-rolled T-shaped steel 20, during the cooling, as shown in FIG. 15, there exists a problem that the camber in which the side of the flange 22 becomes concave arises. This problem is also pointed out in Patent Literature 1 (the fifth row to the fourth row from the bottom of the second page left column), and in the manufacturing method of the T-shaped steel described in Patent Literature 1, as a countermeasure, rolling of the T-shaped steel is performed. At high temperatures after medium or finish rolling, for example, water is poured on the outer surface of the flange (side without web) to cool the flange, thereby cooling the T-shaped steel while keeping the temperature difference between the stem (web) and the flange as close as possible. (The fifth line from the bottom of the second page right column first line of the third column left column). In addition, Patent Literature 2 discloses the outer surface of the flange of the T-shaped steel or the inner surface of the flange (the side with the web) while conveying the T-shaped steel that has finished hot rolling in the longitudinal direction in a posture in which the web is oriented in a substantially horizontal direction. And water cooling of the outer surface are disclosed.

Japanese Patent Publication No. 43-19671 Japanese Laid-Open Patent Publication No. 2008-126259

However, it turns out that there exist the following problems in the conventional manufacturing method of T-shaped steel described in these patent documents 1 and 2.

That is, in the manufacturing method of the T-shaped steel described in Patent Literature 1, as a countermeasure that warpage occurs in the flange side during cooling of the T-shaped steel, for example, water is poured into the outer surface of the flange during high temperature during rolling or after finish rolling of the T-shaped steel. Although the flange is to be cooled, it is not specifically described where cooling of the flange at any place of a manufacturing facility for manufacturing T-shaped steel can effectively prevent warpage of the T-shaped steel by cooling.

Moreover, although patent document 2 describes cooling (water cooling) of the flange of T-shaped steel which finished hot rolling by water cooling, according to examination of the present inventors, the method of this patent document 2 is described below. You can see that there is a problem.

That is, if the flange of the T-shaped steel is cooled by water cooling after the end of the hot rolling, the flange of the T-shaped steel is shrunk by the water cooling, so that bending to the flange side of the T-shaped steel during cooling and immediately after cooling (the flange side is concave). Warpage) is generated. The temperature difference between the flange and the web is about 100 ° C. or higher at the end of hot rolling, and strong cooling must be performed to prevent warpage of the product by cooling the flange so as to eliminate the temperature difference after hot rolling. There may be a problem that the warpage to the flange side becomes excessive and T-shaped steel protrudes from the rolling line.

In the case of T-shaped steel, even if the flange is cooled by water cooling, the deflection to the flange side occurs due to the contraction of the flange, so that the flange is water-cooled after hot rolling of the shaped steel having the flange on both the left and right sides of the web, such as H-shaped steel. Compared with the case, the thermal strain relaxation effect is small, and there is a problem that the bending correction effect itself due to the flange cooling is small. In the case of water-cooling flanges of H-beams, if the heat shrinkage of the right and left flanges is equal, no bending occurs in the H-beams, compressive stress acts on the web, and tensile stress acts on the flanges. These stresses are alleviated by the stress relaxation effect by being, and the effect which reduces the residual stress which arises in a shaped steel after cooling to room temperature is acquired. However, in a section steel with a flange only on one side of the web, such as a T section steel, the bending occurs to the flange side even if the flange is water cooled and shrunk, so that the stress generated on the web or the flange is much higher than that of the flanged section on both sides of the web. It becomes a small level and a stress relaxation effect is not fully acquired. As a result, the amount of warpage of the T-shaped steel after cooling to room temperature is hardly improved as compared with the case of not cooling with water.

Next, in Patent Literature 2, the web of the T-shaped steel needs to be conveyed in the longitudinal direction in a substantially horizontal orientation, while cooling the T-shaped steel having only a flange on one side while maintaining the web of the T-shaped steel in the orientation in which the web is approximately horizontal. In order to do so, it is necessary to provide a mechanism for supporting the web tip, which causes a problem that the installation cost becomes expensive. In order to perform sufficient cooling, it is necessary to lengthen a cooling installation, and the cost of a web support mechanism also becomes large as the cooling installation becomes long.

Moreover, the technique of patent documents 1 and 2 also had the following problems.

That is, the material of the T-shaped steel produced by hot rolling is not only general mild steel but also high tensile steel with a yield stress of 325 MPa or more, so-called high-tensile steel, for example, in ship structural T-shaped steel used for shipbuilding. tensile strength steel is required. As a method of manufacturing this high-tensile T-shaped steel, controlled rolling is performed by rolling the temperature of the rolled material to a non-recrystallization temperature or an austenite and ferrite two-phase region. rolling is often applied, and rolling is required at low temperature compared with general mild steel. For low temperature rolling, for example, there is a method in which a rolled material is allowed to stand before intermediate rolling and air cooled until the temperature of the flange becomes lower than the prescribed temperature, but the air cooling takes a long time to cool down to the prescribed temperature. The problem also arises that the rolling time is increased to lower the productivity. In addition, since the T-shaped steel during rolling generally has a thinner web thickness than the flange thickness, the cooling speed of the web is faster than that of the flange, and the temperature difference between the flange and the web in the air is widened. Even if the material can be secured, there has been a problem that the warpage becomes large enough that it is difficult to correct the warpage after cooling.

Since there existed the above problems, in the conventional manufacturing method of T-shaped steel by hot rolling, the problem of the cooling curvature which arises by the temperature difference between a flange and a web cannot be solved, and when manufacturing T-shaped steel by hot rolling It became a big obstacle. Therefore, this invention is made | formed in order to solve the above-mentioned problem, The objective is the manufacturing facility and manufacturing method of T-shaped steel by hot rolling which can make the cooling curvature which arises by the temperature difference between a flange and a web as small as possible. It is to offer.

The present invention for achieving the above object is as follows.

(1) An outer surface water cooling nozzle which cools the flange outer surface of the to-be-rolled material consisting of a web and a flange having a cross-section approximately T-shaped web by a water cooling in the hot rolling line of the T-shaped steel, and an inner surface that cools the inner surface of the flange of the to-be-rolled material by water cooling. At least one of the water cooling nozzles and at least one of the outer surface water cooling nozzles and the inner surface water cooling nozzles is formed from the substantially horizontal state with respect to the upper surface of the roller table on which the web of the rolled material conveys the rolled material. When the tip and the lower end of the flange are inclined to the same height, any of the inclined states of the web is provided at a position and a direction in which water can be poured toward at least either of the outer and inner surfaces of the flange. Cooling device for T-shaped steel hot rolling line.

(2) The cooling apparatus of the T-shaped steel hot rolling line as described in said (1) WHEREIN: The inner surface water cooling nozzle which cools the inner surface of the said flange of the to-be-rolled material is the upper flange inner surface which cools the inner surface of the upper flange of upper side rather than the said web. A water cooling nozzle and a lower flange inner surface water cooling nozzle for cooling the lower flange inner surface lower than the web, and the injection angle of the upper flange inner surface water cooling nozzle is set at an angle of alpha downward relative to the upper surface of the roller table. The injection angle of the lower flange inner surface water cooling nozzle is set to be an angle of upward β with respect to the upper surface of the roller table, and the injection angle β of the lower flange inner surface water cooling nozzle is larger than the injection angle α of the upper flange inner surface water cooling nozzle ( (<<) The cooling apparatus of the T-shaped steel hot rolling line characterized by the above-mentioned.

(3) A priming molding mill for rolling a raw material steel piece conveyed from a heating furnace into a rolled material consisting of a web having a substantially T-shaped cross section and a flange; and provided at the rear end of the priming molding mill, Intermediate rolling mill group for rolling the said rolled material which consists of a roughly rolled-section substantially T-shaped web and a flange to the to-be-rolled material which consists of a web and a flange of a substantially product dimension, and is provided in the rear end of the said intermediate rolling mill group, and said intermediate | middle rolling mill A manufacturing facility for T-shaped steel by hot rolling, comprising: a finish rolling mill for finishing rolling the rolled material rolled into roughly product dimensions by a smoke group into a T-shaped steel consisting of a web and a flange having a product dimension, the front surface of the intermediate rolling mill group ( Cooling apparatus of the T-shaped steel hot rolling line as described in said (1) or (2) in at least any one of a front side and a back side. Production equipment of T-beams, characterized in that a.

(4) The manufacturing equipment for T-shaped steel according to (3), wherein the cooling device is disposed outside the rolling mill body of the intermediate rolling mill group.

Here, the rolling mill main body means the main body of the rolling mill at the foremost surface of the intermediate rolling mill group when the cooling device is installed on the front side of the middle rolling mill group, and the middle of the middle rolling mill group when the cooling device is installed on the rear side of the middle rolling mill group. It points to the main body of the rolling mill of the last surface. In addition, the outer side of a rolling mill main body means the housing which accommodates the roll chocks etc. which support the rolling roll of a corresponding rolling mill, and the outer side of guides provided continuously to the inside of a housing.

(5) In the manufacturing equipment of T-shaped steel as described in said (3) or (4), what provided the cooling apparatus of the T-shaped steel hot rolling line as described in said (1) or (2) in the whole surface of the said finish rolling mill. T-shaped steel manufacturing equipment characterized in that.

(6) The manufacturing equipment for T-shaped steel described in (5) above, wherein the cooling device is disposed outside the rolling mill body of the finishing rolling mill.

Here, the outer side of a rolling mill main body means the housing which accommodates roll chocks etc. which support the rolling roll of a rolling mill, and the outer side of the guides provided continuously to the inside of a housing.

(7) In the manufacturing equipment for T-shaped steel according to any one of (3) to (6), the intermediate rolling mill group has a substantially T-shaped cross-section web in which the width of the outer circumferential surface of the roll is roughly rolled by the primary molding mill. A first primitive universal rolling mill having an upper and lower horizontal roll wider than an inner height of web formed of a flange; an edge rolling mill for pressing down a cross section of a flange of the rolled material; and a roll outer peripheral surface. A second horizontal roll having a width of less than or equal to a web internal dimension of the material to be rolled, and a left and right vertical roll that one side presses the flange in its plate thickness direction and the other side presses the cross section of the web in the height direction of the web. A production facility for T-shaped steel, comprising a primary universal rolling mill.

(8) A rough molding rolling step of roughly rolling the raw material steel conveyed from the heating furnace with a rolled material consisting of a web and a flange having a cross-section roughly T-shaped web by a rough molding rolling mill; and roughly a cross section roughly rolled by the rough molding rolling process. An intermediate rolling step of rolling the rolled material formed of the T-shaped web and the flange into a rolled material formed of the web and the flange of the product dimensions by an intermediate rolling mill group, and the pressure to be rolled to approximately the product dimension by the intermediate rolling process. A method for producing a T-shaped steel by hot rolling comprising a finish rolling step of finishing rolling a soft material into a T-shaped steel consisting of a web and a flange having a product dimension by a finish rolling mill, wherein in the intermediate rolling step, the front surface of the intermediate rolling mill group and In at least one of the back surfaces, the web of the rolled material conveys the rolled material. At least any of the outer surface and the inner surface of the flange, in any inclined state of the web, in the case where the front end of the web and the lower end of the flange are inclined from the substantially horizontal state with respect to the upper surface of the roller table. Method for producing a T-shaped steel, characterized in that to be cooled by water cooling toward the thing.

(9) In the manufacturing method of the T-shaped steel as described in said (8), in the said finish rolling process, it is about the upper surface of the roller table which the said web of the to-be-rolled material conveys the said to-be-rolled material in the front surface of the said finish rolling mill. When the front end of the web and the lower end of the flange are inclined from the horizontal state to the state of the same height, cooling is performed by water cooling toward at least one of the outer and inner surfaces of the flange in any inclined state of the web. The manufacturing method of the T-shaped steel characterized by the above-mentioned.

In addition, rolling in each rolling mill of the to-be-rolled T-shaped rolled material in this invention shall be performed in the attitude | position which a web becomes horizontal.

In the present invention, the cooling apparatus of the T-shaped steel hot rolling line according to (1) has an outer surface water cooling nozzle for water cooling the flange outer surface of the T-shaped steel, which is a rolled material, and / or an inner surface water cooling nozzle for water cooling the flange inner surface, and an outer surface water cooling nozzle. And / or the inner surface water-cooled nozzle is inclined from the substantially horizontal state with respect to the upper surface of the roller table on which the web of the rolled material conveys the rolled material from the state where the tip of the web and the lower end of the flange are at the same height. Even in an inclined state, it is provided in the position and direction which can be watered toward the outer surface and the inner surface of the said flange. For this reason, even when a plurality of outer surface water cooling nozzles and inner surface water cooling nozzles are arranged as a cooling device in the rolling direction (the conveying direction) of the rolled material, the nozzles are not subjected to the difference in the inclined state of the web at the installation position of each nozzle. The height direction position and the cooling angle of the cooling water are the same, and the equipment structure can be simplified and the equipment cost can be reduced. Moreover, since the web of the to-be-rolled material does not need to be conveyed in the longitudinal direction in the attitude | position which aims at substantially horizontal direction, the mechanism which supports the web tip of a to-be-rolled material becomes unnecessary, and equipment cost can be reduced.

Further, in the present invention, the cooling apparatus of the T-shaped steel hot rolling line according to the above (2) is an inner surface water cooling nozzle that cools the inner surface of the flange of the T-shaped steel, which is the rolled material, and an upper flange inner surface that cools the upper flange upper surface than the web. It has a water cooling nozzle and the lower flange inner surface water cooling nozzle which cools the lower flange inner surface lower than a web, and the injection angle of an upper flange inner surface water cooling nozzle is made into the angle of (alpha) down with respect to the upper surface of a roller table, and the lower flange inner water cooling Since the injection angle of the nozzle is set to the angle of the upward β with respect to the upper surface of the roller table, and the injection angle β of the lower flange inner surface water cooling nozzle is set larger than the injection angle α of the upper flange inner surface water cooling nozzle (α <β), In any inclined state of the web, the cooling water injected onto the upper and lower flange inner surfaces collide at an angle closer to the vertical, thereby improving the cooling capacity. Moreover, the difference in the cooling state of an upper and lower flange becomes small, and the temperature difference of an upper and lower flange can be made small.

According to the production facility of the T-shaped steel according to the above (3) and the method of manufacturing the T-shaped steel according to the above (8) of the present invention, in the front and / or rear of the intermediate rolling mill group, the flange of the rolled material is cooled by water cooling during rolling. Since it is made to cool, by rolling a to-be-rolled material during water cooling, the amount of warpage which arises in a to-be-rolled material by one water cooling can be made small. Further, the warpage generated by the water cooling to each flange can be straightened by applying plastic working in the next rolling, and even if the flange is water-cooled so as to reduce the temperature difference between the flange and the web, the warping to the flange to be rolled can be reduced. Therefore, the warpage generated during rolling due to the water cooling of the flange is small, and the T-shaped steel can be rolled without causing problems such as protruding out of the line of the rolled material due to the warpage.

Moreover, according to the manufacturing equipment of T-shaped steel as described in said (4) in this invention, since the cooling apparatus is arrange | positioned on the outer side of the rolling mill main body of an intermediate rolling mill group, the rolling mill of the intermediate rolling mill group which has no space and is difficult to install a cooling apparatus. Compared with the case where the cooling device is arranged in the main body, a large cooling capacity can be obtained with a small equipment cost. In addition, since the web is generally inclined on the outer side of the rolling mill body, the cooling water sprayed toward the inner surface of the upper flange is drained without remaining on the upper surface of the web, and thus, uneven cooling on the upper and lower surfaces of the web can be suppressed. have.

In the present invention, according to the production facility of the T-shaped steel according to the above (5) and the method of manufacturing the T-shaped steel according to the above (9), the flange of the rolled material is cooled by water cooling on the front surface of the finish rolling mill. Cooling warpage generated by the temperature difference between the flange and the web can be made smaller. In addition, according to the manufacturing equipment for T-shaped steel according to (6) in the present invention, since the cooling device is disposed outside the rolling mill body of the finishing rolling mill, the rolling mill body of the finishing rolling mill has no space and is difficult to install the cooling device. Compared with the case where the cooling device is arranged, a large cooling capacity can be obtained with a small equipment cost. In addition, since the web is generally inclined on the outer side of the rolling mill body, the cooling water sprayed toward the inner surface of the upper flange is drained without remaining on the upper surface of the web, and thus, uneven cooling on the upper and lower surfaces of the web can be suppressed. have.

Moreover, according to the manufacturing equipment for T-shaped steel according to (7) in the present invention, the intermediate rolling mill group includes a web having a substantially T-shaped cross section and a flange whose width of the outer peripheral surface of the roll is roughly rolled by the initial molding mill. A first primary universal rolling mill having an upper and lower horizontal roll wider than the web internal dimension of the rolled material, an edge rolling mill for rolling down the end face of the flange of the rolled material, and a width of the outer circumferential surface of the rolled material of the upper and lower sides A second roll universal rolling mill is provided with a horizontal roll and a vertical roll on either side which pushes the flange in its plate thickness direction and pushes the cross section of the other web in the height direction of the web. For this reason, with the hot rolling, the shape of the edge part is favorable and the web of the web height satisfying a target value is obtained, and it is not necessary to cut | disconnect a web tip part after hot rolling. Since the cutting process becomes unnecessary, it is possible to shorten the manufacturing process and reduce the manufacturing cost. In addition, by changing the balance between the reduction ratio of the web and the flange with the first and second primary universal rolling mills, the warpage of the exit of the rolled material can be controlled by rolling, thereby facilitating the bending control of water cooling. Can be.

In addition, the T-shape for shipbuilding whose web thickness is smaller than the flange thickness and whose web height is more than twice the width of the flange has a high temperature difference between the flange and the web in hot rolling, and it is difficult to correct the cooling deflection after hot rolling. The application of the present invention is particularly effective.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram of embodiment of the manufacturing equipment of T-shaped steel which concerns on this invention.
It is a figure which shows the state which arrange | positioned the cooling apparatus which concerns on this invention on the outer side of the rolling mill main body of the 1st primary universal rolling mill which comprises an intermediate rolling mill group.
3 (a) is a schematic view for explaining the configuration of the cooling device of the present invention and the cooling situation by the cooling device when the rolled material is in the vicinity of the rolling roll, and FIG. 3 (b) and FIG. 3 ( c) is a schematic diagram for demonstrating the cooling situation by the cooling apparatus until the to-be-rolled material falls from a rolling roll and a web inclines and climbs on a roller table.
It is a schematic diagram for demonstrating the other structure of the cooling apparatus of this invention.
It is a schematic diagram for demonstrating still another structure of the cooling apparatus of this invention.
FIG. 6: is a schematic diagram for demonstrating the 1st primary universal rolling mill used for the manufacturing equipment of the T-shaped steel shown in FIG.
FIG. 7: is a schematic diagram for demonstrating the edge mill used for the manufacturing equipment of the T-shaped steel shown in FIG.
FIG. 8: is a schematic diagram for demonstrating the 2nd primary universal rolling mill used for the manufacturing equipment of the T-shaped steel shown in FIG.
FIG. 9: is a schematic diagram for demonstrating the modification of the 2nd primary universal rolling mill used for the manufacturing equipment of T-shaped steel shown in FIG.
FIG. 10: is a schematic diagram for demonstrating the finishing rolling mill used for the manufacturing equipment of the T-shaped steel shown in FIG.
11 is a cross-sectional view of a T-beam.
It is a schematic block diagram which shows the conventional manufacturing equipment of T-shaped steel.
FIG. 13 (A) is a schematic diagram for explaining a primary molding mill used for a conventional T-shaped steel manufacturing facility, and FIG. 13 (B) for illustrating a primary universal rolling mill used for a conventional T-shaped steel manufacturing facility. It is a schematic diagram, FIG. 13 (C) is a schematic diagram for demonstrating the edge mill used for the conventional manufacturing equipment of T-shaped steel, and FIG. 13 (D) is the finishing universal rolling mill used for the conventional manufacturing equipment of T-shaped steel. It is a schematic diagram for illustration.
It is sectional drawing of the T-shaped steel piece of substantially T-shaped cross section shape.
It is a partial perspective view for demonstrating the bending state to the flange side in the middle of cooling of a T-beam.

(Form to carry out invention)

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram of embodiment of the manufacturing equipment of T-shaped steel which concerns on this invention. The manufacturing equipment 1 of the T-shaped steel shown in FIG. 1 has a primary molding mill 2 and an intermediate rolling mill group 3 from the upstream side to the downstream side, that is, from the front end side to the rear end side. And the finishing mill 7 are sequentially arranged.

The primary molding rolling mill 2 reciprocally rolls a rolled material (material steel piece, not shown) conveyed from a heating furnace (not shown) onto a roller table (not shown) to a web and a flange having a cross-section approximately T-shaped. The primary rolling is performed with the rolled material (T-shaped steel piece, see FIG. 14) to be formed (H) (primary molding rolling step). As the primitive molding rolling mill 2, a well-known facility can be used, for example, let it be a double rolling mill equipped with the roll which has a ball mold.

The intermediate rolling mill group 3 is provided in the rear end of the primary molding rolling mill 2, and the to-be-rolled material which consists of the web 21 and flange 22 of the substantially T-shaped cross section which were primary rolled by the primary molding rolling mill 2, and was rolled. (H) is rolled by the to-be-rolled material H which consists of the web 21 and the flange 22 of a substantially product dimension (middle rolling process). In this embodiment, this intermediate rolling mill group 3 is the 1st primary universal rolling mill 4 shown in FIG. 6, and the edge mill 5 shown in FIG. 7 provided in the rear end of this 1st primary universal rolling mill 4. As shown in FIG. ) And the second primary universal rolling mill 6 shown in FIG. 8 provided at the rear end of the edge mill 5. In addition, although this intermediate rolling mill group 3 is comprised by two primary universal rolling mills and one edger rolling mill, this is an example, There is no restriction | limiting in the number of the rolling mills of the intermediate rolling mill group 3, For example, You may comprise one universal rolling mill and one edger rolling mill. Moreover, the structure of three or more primary universal rolling mills and two or more edge mills may be sufficient.

Here, as shown in FIG. 6, the 1st primitive universal rolling mill 4 has a pair of horizontal rolls 41a and 41b which rotate around a horizontal axis, and a pair of left and right which rotate around a vertical axis. Has vertical rolls 42a and 42b. The top and bottom pair of horizontal rolls 41a and 41b and the left and right pair of vertical rolls 42a and 42b are disposed to face each other. The width W1 of the outer circumferential surface of the horizontal rolls 41a and 41b is set larger than the internal dimension L of the web 21 of the rolled material H (the distance from the flange inner surface to the web tip). The width W1 of the outer circumferential surface of the horizontal rolls 41a and 41b is preferably 105 to 150% of the inner diameter L of the web 21.

In the 1st primary universal rolling mill 4, the whole surface of the height direction of the web 21 is pressed down by the horizontal roll 41a, 41b to plate | board thickness direction, and the vertical roll 42a and the horizontal roll 41a, On the side of 41b), the flange 22 is pressed down in the plate thickness direction. The plate thickness adjustment of the web 21 is performed by the opening degree adjustment of the horizontal rolls 41a and 41b, and the plate thickness adjustment of the flange 22 is with the side surfaces of the vertical roll 42a and the horizontal rolls 41a and 41b. The opening degree is adjusted.

Moreover, as shown in FIG. 7, the edge rolling mill 5 has the edge roll 51a, 51b provided with the large diameter roll part 53 and the small diameter roll part 52 in the horizontal axis direction, and the large diameter roll part 53 is pressurized. The web 21 of the extending | stretching material H is guide | induced, and the roll surface 52a of the small diameter roll part 52 presses down the cross section of the flange 22 to the axial direction. As for the roll diameter of the large diameter roll part 53, and the roll diameter of the small diameter roll part 52, the roll surface of the large diameter roll part 53 makes the roll surface of the web 21 during the rolling of the cross section of the flange 22 by the small diameter roll part 52. It is preferable to adjust so that a little space may exist in the upper and lower surfaces of a plate thickness direction. By forming a small gap, the large-diameter roll portion 53 acts as a guide while eliminating the extra rolling reaction generated when the large-diameter roll portion 53 contacts the web 21, and the upper and lower flange ends of the upper and lower web surfaces are guided. The effect of matching the length up to is produced, and the dimensional accuracy can be improved. It is preferable to make a gap 2 mm or less.

Moreover, as shown in FIG. 8, the 2nd primitive universal rolling mill 6 has a pair of the upper and lower horizontal rolls 61a and 61b which rotate about a horizontal axis, and a pair of left and right which rotate around a vertical axis. The vertical rolls 62a and 62b are provided. The upper and lower pairs of horizontal rolls 61a and 61b and the left and right pairs of vertical rolls 62a and 62b are disposed to face each other. The width W2 of the roll outer circumferential surface of the horizontal rolls 61a and 61b is equal to or less than the internal dimension L of the web 21 of the rolled material H (distance from the flange inner surface to the web tip). The width W2 of the roll outer peripheral surface of the horizontal rolls 61a and 61b is preferably about 70 to 100% of the inner diameter L of the web 21. In addition, it is preferable to secure the difference between W1 and W2 by 30 mm or more. When the flange 22 of the rolled material H is pushed to the side surfaces of the horizontal rolls 61a and 61b, the tip end portion of the web 21 projects outward from the roll surfaces of the horizontal rolls 61a and 61b. The web 21 can be pressed down at 62b.

In addition, when the width W2 of the outer peripheral surface of the rolls of the horizontal rolls 61a and 61b of the 2nd primary universal rolling mill 6 is made to be equal to the internal resistance dimension L of the web 21 of the to-be-rolled material H, 9, it is preferable to use what processed the corner part c by the front end side of the web 21 in the shape which does not roll a web surface. Since the width W2 of the roll outer circumferential surface of the horizontal rolls 61a and 61b is the same dimension as the internal dimension L of the web 21, it is possible to press the tip of the web 21 with the vertical roll 62b. In addition, since a space is formed between the front end portion of the web 21 and the horizontal rolls 61a and 61b by the corner portion c processed into a shape that does not roll the web surface, the front end portion of the web 21 By decreasing, the web thickness increase can be absorbed. As processing of the corner part c, circular arc shape processing, a chamfering process, step processing, etc. may be performed, for example.

In the 2nd primary universal rolling mill 6, the roll opening degree of the horizontal rolls 61a and 61b is adjusted, the plate | board thickness of the web 21 is adjusted, and one of the vertical roll 62a and the horizontal rolls 61a and 61b is carried out. The thickness of the web 21 is adjusted by adjusting the plate thickness of the flange 22 by adjusting the opening degree with the side surface of the flange 22, and by adjusting the opening degree between the vertical roll 62b and the other side surface of the horizontal rolls 61a and 61b. Adjust the shape of the end.

In the intermediate rolling process by the 1st primary universal rolling mill 4, the edge rolling mill 5, and the 2nd primary maintenance rolling mill 6 which comprise the above-mentioned intermediate rolling mill group 3, the shape which can be finish-rolled is Reciprocating rolling is performed until it is obtained. In the intermediate rolling step, the flange is rolled in a state inclined outward from the vertical.

And the finishing rolling mill 7 is installed in the rear of the intermediate rolling mill group 3, and rolls the to-be-rolled material H rolled by the intermediate rolling mill group 3 to the product dimension substantially in the product dimension web 21 and a flange. Finish-rolling is performed by the T-shaped steel 20 which consists of (22) (finishing rolling process). The finishing rolling mill 7 is comprised by the finishing universal rolling mill, and as shown in FIG. 10, the upper and lower pair of horizontal rolls 71a and 71b which rotate around a horizontal axis, and the left and right which rotate around a vertical axis | shaft. A pair of vertical rolls 72a and 72b are provided. Side surfaces of the horizontal rolls 71a and 71b are perpendicular to the roll surface. When the flange 22 of the to-be-rolled material H is rolled lightly by the vertical roll 72a, the flange 22 is formed perpendicularly to the web 21. As shown in FIG. The horizontal rolls 71a and 71b can be prevented from moving in the axial direction by pressing the vertical rolls 72b on the side surfaces of the horizontal rolls 71a and 71b not facing the flanges 22.

In the finish universal rolling mill, the web 21 is hardly reduced or reduced to a degree that the shape and dimensions are adjusted. In particular, when rolling in the second universal rolling mill 6 causes a difference in plate thickness between a portion pressed down by the horizontal rolls 61a and 61b and a portion not pressed down (near the tip end portion of the web 21). Relieve pressure to resolve this. In order to achieve this object, the width of the pressed surface of the horizontal rolls 71a and 71b is made larger than the web internal dimension. Preferably, it is about 105 to 150% of the internal law dimension L of the web 21.

The finish universal rolling mill and the primary universal rolling mill generally have different shapes of the vertical rolls on the flange 22 side. That is, in a primary universal rolling mill, as shown in FIG. 8, although the main surface of the vertical roll 62a becomes a mountain shape according to the inclination of a flange, in the finishing universal rolling mill, as shown in FIG. The main surface of the vertical roll 72a has a straight line shape.

And in the manufacturing equipment 1 of the T-shaped steel of this embodiment, as shown in FIG. 1, the front surface (facing face side of the primary molding rolling mill) and the back surface (finishing universal rolling mill) of the intermediate rolling mill group 3 are shown. On the opposite side), that is, on the front surface of the first primary universal rolling mill 4 and the rear surface of the second primary universal rolling mill 6, cooling devices 8 and 9 are provided.

2 shows the cooling device 8 provided on the front surface of the first prismatic universal rolling mill 4. The first primary universal rolling mill 4 includes a housing that houses roll chocks and the like that support a pair of vertical rolls 41a and 41b and a pair of vertical rolls 42a and 42b (not shown). 11) and web guides 12a to 12d fixed to the housing 11 to guide the rolled material H around the pass line center of the space surrounded by the horizontal rolls 41a and 41b and the vertical rolls 42a and 42b. Equipped. And the cooling apparatus 8 is provided in the outer side of the front surface with respect to the rolling mill main body containing the housing 11 and the web guides 12a-12d, and has several water cooling nozzles arranged along the rolling line, and are to be rolled. It is comprised so that the outer surface and inner surface of the flange 22 of (H) may be cooled.

The cooling device 8 has the outer surface water cooling nozzle 8a which injects a cooling water toward the outer surface of the flange 22 of the to-be-rolled material H, as shown to FIG. 3 (a). Here, in the state shown to FIG. 3 (a), the to-be-rolled material H is in the vicinity of the horizontal roll 41a, 41b and the vertical roll 42a, 42b of the 1st primary universal rolling mill 4, The rolling posture is maintained and the web 21 is in a substantially horizontal state with respect to the upper surface of the roller table 13. On the other hand, when the to-be-rolled material H falls from the 1st primary universal rolling mill 4, the web 21 of the to-be-rolled material H is substantially horizontal with respect to the upper surface of the roller table 13 which conveys the to-be-rolled material H. FIG. From the state, as shown in FIG.3 (b), the front-end | tip of the web 21 descends and the web inclines, and as shown in FIG.3 (c) from several meters away, as shown in FIG.3 (c) of the web21 The tip contacts and inclines to the state of the same height as the lower end of the flange 22. The distance from the state of FIG. 3 (a) to the state of FIG. 3 (c) at this time differs also according to the dimension and intensity | strength of the to-be-rolled material H. FIG. As shown in FIGS. 3A to 3C, the outer surface water-cooling nozzle 8a of the cooling device 8 is flushed toward the outer surface of the flange 22 in any inclined state of the web 21. It is installed in possible positions and directions.

In addition, in the cooling device 8, as shown in FIG.3 (a), the upper and lower pair of inner surface water cooling nozzles 8b and 8c which water-injects toward the inner surface of the flange 22 of the to-be-rolled material H (henceforth, The upper flange inner surface water cooling nozzle 8b and the lower flange inner surface water cooling nozzle 8c) are provided. These upper flange inner surface water cooling nozzles 8b and lower flange inner surface water cooling nozzles 8c are rolled materials H similar to the outer surface water cooling nozzles 8a as shown in Figs. 3 (a) to 3 (c). ), The web 21 of which is inclined from the substantially horizontal state with respect to the upper surface of the roller table 13 which conveys the to-be-rolled material H to the state where the front-end | tip of the web 21 and the lower end of the flange 22 are the same height. In the case, in any inclined state of the web 21, the web 21 is provided at a position and a direction where water can be poured toward the inner surface of the flange 22. Therefore, the outer surface water cooling nozzle 8a, the upper flange inner surface water cooling nozzle 8b, and the lower flange inner surface water cooling nozzle 8c are arranged in the rolling direction (transfer direction) of the to-be-rolled material H, and the cooling apparatus 8 is arranged. In this case, the height direction position of the nozzle and the spray angle of the cooling water are the same, regardless of the difference in the inclined state of the web in the installation position of each nozzle, so that the equipment structure can be simplified and the equipment cost can be reduced.

In addition, since the flange of the to-be-rolled material H can be cooled even when the to-be-rolled material H is conveyed away from the 1st primary universal rolling mill 4 in the inclined state, the web is horizontally The web tip support facility to hold | maintain is unnecessary, and an installation cost can be reduced. Moreover, a cooling installation can be provided to the position away from a rolling mill, and the freedom degree which improves a cooling capability by increasing a cooling length becomes high.

In addition, the outer surface water cooling nozzle 8a, the upper flange inner surface water cooling nozzle 8b, and the lower flange inner surface water cooling nozzle 8c are only one (only the outer surface water cooling nozzle 8a or the upper flange, depending on the required cooling capacity). Only the inner surface water cooling nozzle 8b and the lower flange inner surface water cooling nozzle 8c) may be provided, or only one of them may be used depending on the required cooling capacity.

Here, the temperature of the inner surface of the flange 22 of the rolled material H is often higher than that of the outer surface. This is because, while the flange inner surface receives radiant heat from the high-temperature web, the temperature of the flange tends to decrease because a high temperature object does not exist near the flange outer surface. In addition, the inner surface of the flange is different from the rotational movement direction of the horizontal roll side and the moving direction of the rolled material, so the slippage between the roll and the rolled material surface is large, and the heat generated by friction is large. Since the advancing direction of the to-be-rolled material is the same, the frictional heat generation also contributes. Therefore, when only one of them is cooled, it is preferable to install or use only the upper flange inner surface water cooling nozzle 8b and the lower flange inner surface water cooling nozzle 8b so as to cool the inner surface of the flange having a high temperature.

In addition, the cooling device 8 is preferably provided so that the injection angle of the cooling water from the upper flange inner surface water cooling nozzle 8b is downward from the horizontal in order to effectively cool the inner surface of the upper flange in a state where the web is horizontal. . When the injection angle is made downward, in the state where the web is horizontal, the cooling water for cooling the inner surface of the upper flange hardly touches the web. Moreover, the upper flange inner surface water cooling nozzle 8b can be provided on the left and right side guides (not shown) which guide | induce the to-be-rolled material H to a rolling mill, and there also exists an advantage that the installation cost of nozzle installation can be made cheap. On the other hand, the lower flange inner surface water-cooled nozzle 8c is installed so as to have an injection angle upward from the horizontal position at a position lower than the upper surface of the roller table for the purpose of effectively cooling the lower flange inner surface without disturbing the operation of the left and right side guides. It is desirable to.

Here, as shown in FIG. 4, the cooling device 8 has an upward injection angle from the horizontal of the lower flange inner surface water cooling nozzle 8c than the downward injection angle α of the upper flange inner surface water cooling nozzle 8b from the horizontal. It is preferable to install so that (beta) may become large. This is because the posture of the rolled material H is substantially horizontal as shown in Fig. 3A, and is limited to the vicinity of the horizontal rolls 41a and 41b and the vertical rolls 42a and 42b. This is because the web 21 is inclined on the outer side of the rolling mill body. That is, in manufacture of T-shaped steel by hot rolling, the state in which the web 21 of the to-be-rolled material H is inclined is common, and the water cooling apparatus suitable for this state is effective. When the upstream injection angle β of the lower flange inner surface water cooling nozzle 8c is increased from the horizontal downward injection angle α of the upper flange inner surface water cooling nozzle 8b, the flange 22 of the rolled material H The angle between the direction of the coolant that cools the inner surface of the lower flange and the web increases, making it difficult for the coolant to reach the web, which makes it difficult to reduce the temperature of the web without the need for cooling. Further, even when the web 21 of the rolled material H is inclined, the angle at which the coolant collides with the inner surface of the lower flange of the flange 22 of the rolled material H is close to the vertical, thereby improving cooling ability. It works. 4, the downward inclination angle may also be provided in the outer surface water cooling nozzle 8a which cools the flange outer surface of the flange 22 of the to-be-rolled material H. As shown in FIG.

In addition, although the specific angle of each water cooling nozzle can be suitably determined according to the specification of a to-be-rolled material and equipment, (alpha) is about 5-50 degrees, (beta) is about 15-60 degrees, and the downward inclination angle of the outer surface water cooling nozzle 8a is 0-. About 45 degrees are preferable. Moreover, it is preferable that (beta) is about 10-40 degrees larger than (alpha). As shown to FIG. 4 and FIG. 5, the injection angle means the angle which the center line (normally the direction of a nozzle) of the jet from a nozzle makes horizontal.

In addition, in FIG. 4, both the upper flange inner surface water cooling nozzle 8b and the lower flange inner surface water cooling nozzle 8c are located outside the tip of the web 21 of the to-be-rolled material H, The upper flange inner surface water cooling nozzle 8b and the lower flange inner surface water cooling nozzle 8c have a positional relationship which is hard to collide. In addition, as shown in FIG. 5, when the lower flange inner surface water cooling nozzle 8c is provided between the pair of adjacent rollers which comprise the roller table 13, there exists no possibility that the to-be-rolled material H may collide, Lower flange inner surface The water-cooled nozzle 8c can be adjacent to the lower flange inner surface of the flange 22 of the rolled material H, so that the same cooling capacity as the upper flange inner surface can be obtained with lower water pressure or less water as an effect of proximity. As a result, the equipment cost can be reduced. In addition, each water cooling nozzle of the cooling apparatus 8 shown to FIGS. 3-5 is a mechanism which can adjust an injection angle, and the structure which can set an appropriate injection angle according to the dimension of the T-shaped steel to manufacture is preferable.

Moreover, the cooling apparatus 9 provided in the back surface of the 2nd primary universal rolling mill 6 also has the housing main body which comprises the 2nd primary universal rolling mill 6, and the rolling mill main body which contains a web guide (not shown). It is provided outside the rear surface, and has the same configuration as the cooling apparatus 8 shown in Figs. 3 to 5 (outer surface water cooling nozzle 9a, upper flange inner surface water cooling nozzle 9b, lower flange inner surface water cooling nozzle 9c, etc.). )

In the intermediate rolling process by the intermediate rolling mill group 3, these cooling apparatuses 8 and 9 water-cool the flange 22 of the to-be-rolled material H during rolling in the front and back of the intermediate rolling mill group 3. By cooling. Specifically, the cooling apparatuses 8 and 9 divide water into plural times between the passes of the reciprocation rolling by the intermediate rolling mill group 3, and perform the water cooling of the flange 22. FIG. Accordingly, by rolling the rolled material H during water cooling, the amount of warpage generated in the rolled material H by one water cooling can be reduced. In addition, the warpage generated by the water cooling to each of the flanges 22 can be straightened by applying plastic working in the next rolling, and even if the flanges 22 are water-cooled so as to reduce the temperature difference between the flanges 22 and the webs 21, the pressure is applied. The warping to the flange 22 side of the extension material H can be kept small. For this reason, T-shaped steel can be manufactured smoothly, avoiding the trouble by the large cooling bending which the conventional technique of cooling a flange at once after hot rolling in the back surface of the finishing mill (finishing universal rolling mill) 7 is carried out.

In addition, when the flange 22 of the rolled material H is strongly cooled at one place in the intermediate rolling mill group 3, the rolled material H bends toward the flange 22 side in the same way as the conventional art. Therefore, there is a problem in the rolling operation. For this reason, it is necessary to cool the flange 22 by dividing into multiple times in the middle of rolling, and for this reason, it is preferable to provide cooling apparatuses 8 and 9 in each of the front and rear surfaces of the intermediate rolling mill group 3. However, when the required cooling capacity is obtained, the cooling device 8 or 9 may be provided on either the front or rear surface of the intermediate rolling mill group 3. In addition, it is not necessary to use these cooling apparatuses 8 and 9 between all the reciprocal rolling passes | passes, and the path | route which performs cooling according to the temperature of the to-be-rolled material H, the capability of the cooling apparatuses 8, 9, etc. suitably is appropriate. It is good to select and cool between arbitrary some path | passes.

Moreover, the cooling apparatus 10 of this invention shown in FIGS. 3-5 is provided also in the front surface of the finishing mill (finishing universal rolling mill) 7. In the finish rolling process, the cooling device 10 cools the flange 22 of the to-be-rolled material H by water cooling in the front surface of the finish rolling mill 7. By providing this cooling apparatus 10, since the flange 22 of the to-be-rolled material H can be cooled also in a finishing rolling process, the cooling apparatus 8 and 9 are provided in the front and back of the intermediate rolling mill group 3. Compared with the case where bays are installed, cooling deflection can be effectively prevented. In addition, this cooling apparatus 10 does not necessarily need to be installed. Moreover, you may install the cooling apparatus (not shown) which cools the flange 22 of the to-be-rolled material H by water cooling also in the back surface of the finishing mill 7. As shown in FIG.

Here, it is preferable to determine the length in the rolling direction of the cooling apparatuses 8 and 9 provided on the front and rear surfaces of the intermediate rolling machine group 3 in consideration of cooling capacity, productivity, equipment cost, and the like. For example, when the cooling device is too short and the cooling capacity is insufficient, if the rolling speed is slowed down and replenished, the rolling time is long and productivity is lowered. Therefore, it is desirable to secure a length such that the cooling capacity is not insufficient. On the other hand, if the cooling device is too long, the cooling capacity is improved because the time to pass through the cooling devices 8 and 9 is long, but if the conveyed material (H) is conveyed until it leaves the cooling devices 8 and 9, Since the distance from the intermediate rolling mill group 3 is considerably moved, since the movement time of the to-be-rolled material H in reciprocating rolling is long, productivity falls eventually. Moreover, when the length of the cooling direction of the cooling apparatuses 8 and 9 is excessively long, the quantity of cooling water to be used will increase, and equipment cost, such as a pump and piping, will become excessive. Although the length of the rolling direction of the cooling apparatuses 8 and 9 can be 5 m or more and 20 m or less, for example, It is not limited to this, You may decide suitably according to the specification of a to-be-rolled material and facilities in consideration of said circumstances.

On the other hand, since the rolling in the finish rolling mill 7 is usually one pass or has a small effect on productivity even if the rolling speed is slowed down, the length of the cooling device 10 provided on the front surface of the finish rolling mill 7 is about: It is not necessary to consider very much the same situation as the cooling apparatuses 8 and 9 provided in the front and back of the intermediate rolling mill group 3. Therefore, from the viewpoint of securing the cooling capability, the length is preferably 5 m or more, in the same manner as the lengths of the cooling devices 8 and 9, but there is no problem even if less than 5 m. Alternatively, the maximum length of the cooling device 10 may be a distance between the rear surface of the intermediate rolling mill group 3 and the front surface of the finishing rolling mill 7.

In addition, in this embodiment, the cooling apparatuses 8 and 9 provided in the front and rear of the intermediate rolling mill group 3, and the cooling apparatus 10 provided in the front of the finishing rolling mill 7 are arrange | positioned outside the rolling mill main body, have. This is because there is no space in the rolling mill body, and therefore, installation of an effective cooling device is usually difficult. In addition, when the upper flange inner surface is cooled right next to the rolling mill, since the web is horizontal, there is a possibility that the cooling water stays on the upper surface of the web, resulting in uneven cooling on the upper and lower surfaces of the web. On the other hand, if it is outside of a rolling mill main body, installation of a cooling apparatus is easy and since the web is in a substantially inclined attitude | position, the cooling water sprayed on the upper flange inner surface is drained, without staying on the upper surface of a web. Therefore, it is preferable to arrange | position the cooling apparatus 8, 9, 10 on the outer side of a rolling mill main body.

On the other hand, since the cooling apparatus 8, 9, 10 of this invention can cool a flange also in the attitude | position which the web which is the same as the rolling attitude | position in each rolling mill of the to-be-rolled material H becomes horizontal, as a rolling mill main body, Can be installed in close proximity. For example, in order to improve the rolling efficiency (reducing the rolling time) in the reciprocating rolling in the intermediate rolling step, the distance between the rolling mill main body and the cooling device (closest water cooling nozzle) is better, and the distance between the rolling mill main body and the cooling device is better. It is preferable to make (D) 10 m or less. More preferably, the distance D is 5 m or less.

In addition, when the web of the rolled material, which is a feature of the present invention, is inclined from a substantially horizontal state with respect to the upper surface of the roller table for conveying the rolled material from the front end of the web and the lower end of the flange to the same height, From the viewpoint of cooling the outer surface and the inner surface of the flange even in an inclined state, the cooling device and the cooling method of the present invention, in the case of producing a T-shaped steel having a web height of two times or more the width of the flange used for shipbuilding, etc. Especially very suitable. Since T-shaped steel whose web height is less than twice the width of the flange is in a state where the flange on the roller table is inclined greatly, the collision angle between the coolant and the rolled material to the flange surface of the material to be deviated greatly from the vertical, and the cooling capacity is lowered. There is a case. On the other hand, if the web height is T-shaped steel more than twice the width of the flange, the outer surface water cooling nozzle 8a, the upper flange inner surface water cooling nozzle 8b, and the lower flange inner surface water cooling nozzle 8c are arranged in plural, and the cooling apparatus 8 In this case, even when the height direction position of the nozzle and the spray angle of the coolant are constant at each of the nozzles 8a, 8b, and 8c, the collision angle between the coolant and the flange surface of the rolled material is maintained even in any inclined state of the web. It can be maintained in an appropriate range.

In addition, in this embodiment, when the outer surface water cooling nozzle 8a, the upper flange inner surface water cooling nozzle 8b, and the lower flange inner surface water cooling nozzle 8c are arranged in series, and it is set as the cooling apparatus 8, each nozzle 8a is carried out. , 8b, 8c), the height direction position of the nozzle and the spray angle of the cooling water are made constant, but the present invention is not limited thereto. In order to make the collision angle between the cooling water and the flange surface of the rolled material more suitable, for example, with respect to the outer surface water cooling nozzle 8a, the nozzle height direction position is increased as it is separated from the rolling mill body, and the spray angle of the cooling water is increased. Each nozzle may be provided so that it may become a different height direction position and injection angle according to the inclination state of the flange in the installation position of a nozzle etc.

In FIG. 2, the upper flange inner surface water cooling nozzle 8b and the lower flange inner surface water cooling nozzle 8c are provided at equal intervals with the same phase in the rolling direction, but are not limited to this arrangement. . In other words, the nozzles 8a, 8b, and 8b may be arranged separately at appropriate intervals and in number. For example, the arrangement | positioning space | interval of the rolling direction of a nozzle does not need to be equal intervals, and it is not necessary to match the position of a rolling direction with another nozzle. Moreover, not only the direction of a nozzle but a shape, size, etc. may be suitably selected for every position of a rolling direction. However, from the viewpoint of the cooling control ability, it is preferable to provide nozzles 8a to 8c between rolls as shown in FIG.

Next, the arrangement | positioning of the cooling apparatus 8, 9, 10 considered from the cooling of the flange 22 for manufacturing T-shaped steel of high tenth specification is demonstrated.

In order to manufacture a so-called high-tensile material (high tensile steel having a yield stress of 325 MPa or more) having a high yield stress, generally, controlled rolling is applied in which the temperature of the rolled material is rolled to the unrecrystallized zone or the two-phase zone. In controlled rolling, it is necessary to carry out rolling of the rolling reduction rate (plate thickness reduction rate) more than a certain grade, such as about 30% in these temperature ranges, and to accumulate distortion in a material. By the way, in the finishing rolling process by the finishing rolling mill 7, although the thickness of the flange 22 and the web 21 is slightly reduced, the rolling reduction rate is about 2 to 3%, but the reduction ratio required for control rolling is large. Cannot be satisfied.

Therefore, it is necessary to perform control rolling at least in part of the intermediate rolling process by the intermediate rolling mill group 3 (preferably in several passes from the latter half to the last). That is, it is necessary to drop the temperature of the to-be-rolled material H to the unrecrystallized area | region or two phase area | region in the middle of an intermediate rolling process. If the temperature of the flange 22 is to be lowered by air cooling, there is a problem that the waiting time is long and productivity is lowered. On the other hand, when the flange 22 is cooled by water cooling and the temperature of the flange 22 is lowered, the waiting time is shortened, the productivity is improved, and the flange 22 is cooled faster than the cooling rate at which the web 21 is air-cooled. The effect that the temperature difference between the web 21 and the flange 22 becomes small by this is obtained, and also it is effective in preventing the cooling curvature after rolling. Thus, as a cooling installation of the flange 22 for eliminating the waiting time of the rolling temperature in control rolling, the cooling apparatus of the flange by water cooling in each of the front and rear surfaces of the intermediate rolling mill group 3 is carried out. ) Is preferable.

For this reason, in this embodiment, while providing the cooling apparatuses 8 and 9 of the flange by water cooling in the front surface and the rear surface of the intermediate rolling mill group 3, by the water cooling in the front surface of the finishing rolling mill 7, The cooling device 10 of the flange is provided. When high productivity is not required for the production of high-tensile materials, or when the cost of equipment needs to be reduced, an adequate effect of preventing the cooling warpage of some T-shaped steels is obtained even without installing a cooling device at all positions. In order to attain the cooling warpage prevention effect, it is necessary to provide the cooling devices 8 and 9 of the flanges by water cooling at least on the front and rear surfaces of the intermediate rolling mill group 3. In addition, it is preferable to provide the cooling device 10 of the flange by water cooling in front of the finishing mill 7 in addition to the cooling devices 8 and 9 in order to obtain the largest cooling bending prevention effect of T-shaped steel.

In addition, as mentioned above, in this embodiment, although the intermediate rolling mill group 3 is comprised by two primary universal rolling mills and one edge mill, this is the number of the rolling mills of the intermediate rolling mill group 3 as an example. There is no restriction | limiting in this, For example, you may comprise one primary universal rolling mill and one edger rolling mill. Moreover, the structure of three or more primary universal rolling mills and two or more edge mills may be sufficient. However, in the intermediate rolling mill group (UEU) 3 which arrange | positions the 1st primary universal rolling mill 4 in the front side of the edge mill 5, and the 2nd universal rolling mill 6 in the rear side of the edge mill 5, In the first and second primary universal rolling mills 4 and 6, rolling warpage can be generated on both the flange 22 side and the web 21 side, and the flange 22 can be cooled by water cooling by adjusting the warpage, so that the primary universal rolling mill Compared with the intermediate rolling mill group UEU of one unit and one edge mill, there exists a merit that the water cooling bending control becomes easy.

As shown in FIGS. 6 and 8, the first and second primitive universal rolling mills 4 and 6 reduce the thickness of the web with the horizontal rolls 41a, 41b, 61a, and 61b, respectively, and the flange thickness is reduced by the horizontal rolls. Since it pushes down by the side surface of 41a, 41b, 61a, 61b, and the vertical roll 42a, 62a, the reduction ratio of the web 21 and the flange 22 can be adjusted independently. In general, when the reduction ratio of the web 21 is set to the reduction ratio of the flange 22, since the stretching of the flange 22 is larger than the web 21, the rolled material H bends toward the web 21 side and vice versa. When the reduction ratio of (22) <the reduction ratio of the web 21 is set, the rolled material H is bent to the flange 21 side. Thus, by changing the balance of the reduction ratio of the web 21 and the flange 22, the curvature of the exit side of the to-be-rolled material H can be controlled by the 1st and 2nd primary universal rolling mills 4 and 6. As shown in FIG.

On the other hand, since the edge mill 5 reduces only the end surface of the flange 22, as shown in FIG. 7, the bending to the web 21 side always arises by pressing. Moreover, in order to make a flange width into a target dimension, it is necessary to make the flange width reduction amount of the edge rolling mill 5 into an appropriate quantity, and there is little room for adjusting a reduction amount in order to control a curvature. From this point, the intermediate rolling mill group UEU which arrange | positions the 1st primary universal rolling mill 4 to the front side of the edge mill 5, and the 2nd primary universal rolling mill 6 to the rear side of the edge mill 5 is primary. It is more preferable for the production of T-shaped steel than the intermediate rolling mill (UE) of one universal rolling mill and one edge mill.

(Example)

As a first embodiment, the web height 300 mm, the flange width 100 mm, from a bloom having a rectangular cross section with a thickness of 250 mm and a width of 310 mm, using the T-shaped steel manufacturing equipment 1 shown in FIG. T-shaped steel which made web thickness 9mm and flange thickness 16mm the target dimension was rolled.

As shown in FIG. 1, the cooling apparatuses 8, 9, and 10 were provided before and after the intermediate rolling mill group 3, and the front surface of the finishing rolling mill (finishing universal rolling mill) 7. As shown in FIG. These cooling apparatuses were installed adjacent to the outside of the rolling mill main body, and the distance D between the rolling mill main body and the cooling apparatus was 3 m. The injection direction of flange outer surface water cooling nozzles 8a, 9a, etc. was made 10 degrees downward with respect to the horizontal direction. In addition, the rolling element (H) is incorporated into the side guide on the flange 22 side which guides the rolled material (H) to the rolling mill to follow the side guide and move in the horizontal direction (web height direction). The distance between the outer surface of the flange 22 and the flange outer surface water cooling nozzle was set to be kept constant regardless of the cross-sectional dimension of the rolled material H. The injection direction of the upper flange inner surface water-cooled nozzles 8b, 9b, etc. is 10 ° downward with respect to the horizontal direction, and is mounted on the side guide on the front end side of the web 21 of the rolled material H to move in the horizontal direction. I did it. The injection direction of the lower flange inner surface water cooling nozzles 8c, 9c, etc. was 30 degrees upward with respect to the horizontal direction, and it was set as the structure which follows the side guide on the flange 22 side, and moves to the left-right direction. In addition, each cooling device set it as the structure which arrange | positioned many cooling nozzles of FIG. 5 in the rolling direction, and made the whole cooling length into 10m.

As the primary molding rolling mill 2, a double rolling mill having a vertical roll forming a plurality of balls was used. As the 1st primary universal rolling mill 4 which comprises an intermediate rolling mill group, the thing of the structure shown in FIG. 6 was used. As horizontal roll 41a, 41b, the angle (angle formed between a vertical direction line and the side surface of horizontal roll 41a, 41b) from the perpendicular direction of the side surface used the thing of 7 degrees. The left and right vertical rolls 42a and 42b were disposed so as to face each other, and the cross-sectional shape was a vertically symmetrical mountain shape having a quadrilateral inclined at an angle of 7 ° from the vertical, with the center of the width direction of the roll as the apex. In addition, pressing the side surfaces of the horizontal rolls 41a and 41b among the left and right vertical rolls 42a and 42b is a pressing force so that the horizontal rolls 41a and 41b do not move in the horizontal axis direction during rolling of the flange 22. Adjusted.

As the edge mill 5, the thing of the structure shown in FIG. 7 was used. The inclination angle of the stepped portion was set at an angle of 7 ° from the vertical. As the 2nd primary universal rolling mill 6, the thing of the structure shown in FIG. 8 was used. The horizontal rolls 61a and 61b inclined the side of the side on which the flange 22 was rolled at an angle of 7 ° from vertical. In addition, one vertical roll 62a which rolls the flange 22 among the left and right vertical rolls 62a and 62b is inclined at an angle of 7 ° from the vertical, having the center of the width direction of the roll surface as the vertex in the cross-sectional shape. The vertical roll 62b of the vertically symmetrical mountain shape which has a quadrilateral, and which pushes the front-end | tip part of the web 21 in the height direction was made into the cylindrical shape whose roll surface was flat. The finishing rolling mill 7 used the finishing universal rolling mill of the structure shown in FIG.

Moreover, the cooling apparatuses 8 and 9 provided in the front surface and the rear surface of the intermediate rolling mill group 3 have both the outer surface and the inner surface of the flange 22 over 10 m in length by several nozzles arranged in the rolling direction for water cooling. By cooling the structure. Moreover, the cooling apparatus 10 provided in the front surface of the finishing mill 7 has a structure which can cool both the outer surface and the inner surface of the flange 22 by water cooling over 10 m in length by the some nozzle arranged in the rolling direction. did.

In the production of the T-shaped steel, first, the bloom heated in the heating furnace was rolled by the primary molding rolling mill 2 to obtain a T-shaped steel sheet having a substantially T-shaped cross section as shown in FIG. The web thickness of the obtained T-shaped steel piece was 40 mm, the flange thickness was 75 mm, the web height 375 mm, and the flange width 130 mm. Subsequently, the first rolling universal rolling mill 4, the edge rolling mill 5, and the second rolling universal rolling mill 6 were placed in this order in the intermediate rolling mill group 3 close to each other from the upstream side to the downstream side. Reciprocating rolling was performed and the web 21 and the flange 22 were pressed down. At this time, the flange 22 of the to-be-rolled material H which passes through the cooling apparatus 8 and 9 provided in the front and back surface of the intermediate rolling mill group 3 was cooled by water cooling. In addition, cooling was performed on both the outer surface and the inner surface of the flange 22. Finally, one pass was rolled in the finishing rolling mill 7, and the flange 22 was pressure-reduced to shape the inclination vertically. At this time, both of the flange outer surface and the inner surface of the to-be-rolled material H were cooled by water cooling using the cooling apparatus 10 provided in the front surface of the finish rolling mill 7. In addition, the web part was reduced.

When the surface temperature of the to-be-rolled material H was measured in the back surface of the finishing mill 7, the surface temperature of the flange 22 was 720 degreeC, and the surface temperature of the web 21 was 725 degreeC. This rolled material (H)

The amount of warpage per 10 m of length after cooling to room temperature was very small at 5 mm or less.

In addition, in the second embodiment, the cooling apparatuses 10 and 9 are provided only on the front and rear surfaces of the intermediate rolling mill group 3, without providing the cooling apparatus 10 on the front surface of the finish rolling mill 7, Rolling was performed. The T-shaped steel was rolled in the same process as in the first embodiment, and the flange 22 of the rolled material H passed before and after the intermediate rolling mill group 3 was cooled by water cooling. Before the finish rolling mill 7, finish rolling was performed without performing water cooling. When the surface temperature of the to-be-rolled material H was measured in the back surface of the finishing mill 7, the surface temperature of the flange 22 was 741 degreeC, and the surface temperature of the web 21 was 729 degreeC. In the to-be-rolled material H after cooling, the curvature about 9 mm per 10 m in length generate | occur | produced. In general, the amount of warpage of the shaped steel is considered to be 1 mm or less per 1m, and by slightly modifying the portion exceeding this, the warpage can be made into a product within a tolerance.

On the other hand, as a comparative example, without cooling by the water cooling of the flange 22 before and after the intermediate rolling mill group 3, and before the finishing rolling mill 7, it cools in the back surface of the finishing rolling mill 7, and performs the same hot rolling process. T-shaped steel was rolled. As a result of measuring the surface temperature of the to-be-rolled material H immediately after the finish rolling mill 7, the surface of the flange 22 was 833 degreeC, and the web 21 was 735 degreeC.

As a result of cooling the flange 22 of the rolled material H from the rear side of the finish rolling mill 7, warpage to the flange 22 side occurred in the cooling device, and the rolled material H contacted the cooling device. Therefore, the to-be-rolled material H could not be conveyed and troubled operation. When the to-be-rolled material H was cooled to room temperature, the curvature amount per 10 m of length of the to-be-rolled material H after cooling was about 85 mm. Since the amount of warpage was large, it was found that warpage correction using a press was required, and the manufacturing cost increased, and the press process took a long time to hinder productivity. In particular, since the straightening of the web 21 is performed, a shape defect in which the web 21 is compressed and buckled occurs during the press, and press calibration was very difficult. T-shaped steel, which did not completely fix the shape defect by press calibration, became a scrap, and the yield decreased, and the manufacturing cost increased significantly.

As described above, by using the production equipment and the manufacturing method of the T-shaped steel of the present invention, it is possible to prevent the warpage due to cooling that impedes productivity and to produce the T-shaped steel in large quantities at low cost by hot rolling.

1: Manufacturing equipment of T-beam
2: first forming rolling mill
3: middle rolling mill group
4: first primary universal rolling mill
5: edge rolling mill
6: second primary universal rolling mill
7: finish rolling mill (finishing universal rolling mill)
8, 9, 10: cooling unit
8a, 9a: external water cooling nozzle
8b, 9b: upper flange inner water cooling nozzle
8c, 9c: internal flange water cooling nozzle
11: housing
12a, 12b, 12c, 12d: web guide
13: roller table
20: T section steel
21: Web
22: flange
41a, 41b: horizontal roll
42a, 42b: vertical roll
51a, 51b: edger roll
52: small diameter roll portion
53: large diameter roll portion
61a, 61b: horizontal roll
62a, 62b: vertical roll
71a, 71b: horizontal roll
72a, 72b: vertical roll
101: manufacturing equipment of T-shaped steel (hot rolling equipment)
102: Priming Molding Rolling Mill
102a: upper roll
102b: Harrol
103: intermediate rolling mill group
104: first universal rolling mill
141a, 141b: horizontal roll
142a, 142b: vertical roll
105: edge rolling mill
151a, 151b: edger roll
153: large diameter roll portion
154: small diameter roll portion
106: Finishing Universal Rolling Mill
161a, 161b: horizontal roll
162a, 162b: vertical roll
W1: width of the outer circumferential surface of the horizontal roll of the first primary universal rolling mill
W2: width of outer circumferential surface of horizontal roll of second primary universal rolling mill
L: Web internal law
H: Rolled material
D: Distance between rolling mill body and cooling device
c: corner part of the roll (processing part)

Claims (11)

In the hot rolling line of T-shaped steel, an external surface water cooling nozzle for cooling the flange outer surface of the rolled material, which consists of a substantially T-shaped web and a flange, by water cooling, and an inner surface of the flange of the rolled material. At least one of the inner surface water cooling nozzles cooled by
At least one of the outer surface water cooling nozzle and the inner surface water cooling nozzle has a front end of the web and a lower end of the flange from a state substantially horizontal to an upper surface of a roller table on which the web of the rolled material conveys the rolled material. T-shaped steel hot rolling line provided at a position and a direction where water can be poured toward at least one of the outer surface and the inner surface of the flange in any inclined state of the web when the bottom slopes to a state of the same height. Cooling system. The method of claim 1,
An inner surface water cooling nozzle for cooling the inner surface of the flange of the rolled material includes an upper flange inner surface water cooling nozzle for cooling the upper flange inner surface higher than the web, and a lower flange inner surface water cooling nozzle for cooling the lower flange inner surface lower than the web. I equip it,
The injection angle of the upper flange inner surface water cooling nozzle is an angle of α downward relative to the upper surface of the roller table, and the injection angle of the lower flange inner surface water cooling nozzle is an angle of upward β with respect to the upper surface of the roller table. and,
An injection angle β of the lower flange inner surface water cooling nozzle is set larger (α <β) than an injection angle α of the upper flange inner surface water cooling nozzle. A primary molding mill for rolling the raw material steel piece conveyed from the heating furnace with a rolled material consisting of a web having a T-shaped cross section and a flange, and a first rolling mill installed at the rear end of the primary molding rolling mill, and first rolled by the primary molding rolling mill. An intermediate rolling mill group for rolling the rolled member formed of a web and flange having a substantially T-shaped cross section into a rolled member consisting of a web and a flange having a product dimension, and provided at a rear end of the intermediate rolling mill group, An apparatus for manufacturing T-shaped steel by hot rolling, comprising a finishing mill for finishing-rolling the rolled material rolled to approximately a product dimension into a T-shaped steel consisting of a web and a flange having a product dimension,
The manufacturing equipment of the T-shaped steel provided with the cooling apparatus of the T-shaped steel hot rolling line of Claim 1 or 2 in at least any one of the front surface and the back surface of the said intermediate rolling mill group. The method of claim 3,
The said cooling apparatus is arrange | positioned on the outer side of the rolling mill main body of the said intermediate rolling mill group, The manufacturing equipment of the T-shaped steel characterized by the above-mentioned. The method of claim 3,
The cooling apparatus is provided in the front surface of the said finish rolling mill, The manufacturing equipment of the T-shaped steel characterized by the above-mentioned. The method of claim 4, wherein
The cooling apparatus is provided in the front surface of the said finish rolling mill, The manufacturing equipment of the T-shaped steel characterized by the above-mentioned. The method of claim 5,
The said cooling apparatus is arrange | positioned on the outer side of the rolling mill main body of the said finish rolling mill, The manufacturing equipment of the T-shaped steel characterized by the above-mentioned. The method of claim 6,
The said cooling apparatus is arrange | positioned on the outer side of the rolling mill main body of the said finish rolling mill, The manufacturing equipment of the T-shaped steel characterized by the above-mentioned. The method according to any one of claims 3 to 8,
The said intermediate rolling mill group is the 1st primary universal rolling mill which has the width of the outer periphery surface upper and lower horizontal roll wider than the web internal dimension of the to-be-rolled material which consists of a substantially T-shaped web and the flange which were rolled by the said primary molding mill. An edge rolling mill for reducing the end face of the flange of the rolled material, a horizontal roll of the upper and lower sides of which the width of the outer peripheral surface of the roll is equal to or less than the web internal dimension of the rolled material; One side is equipped with the 2nd primary universal rolling mill which has the left-right vertical roll which presses down the cross section of a web to the height direction of a web, The manufacturing equipment of the T-shaped steel characterized by the above-mentioned. The rough forming rolling process of rolling the raw material steel conveyed from the heating furnace with the to-be-rolled material which consists of a web and a flange of a roughly T-shaped cross section by the rough forming rolling mill, and the roughly T-shaped cross section roughly rolled by the said rough molding rolling process. The intermediate rolling process of rolling the said rolled material which consists of a web and a flange to the to-be-rolled material which consists of a web and a flange of a substantially product dimension by an intermediate rolling mill group, and finishes the said rolled material rolled to about a product dimension by the said intermediate rolling process. As a manufacturing method of T-shaped steel by hot rolling provided with the finishing rolling process which finish-rolls and rolls to T-shaped steel which consists of a web of a product dimension and a flange by a rolling mill,
In the intermediate rolling step, at least one of the front side and the rear side of the intermediate rolling mill group, the tip of the web and the flange are substantially horizontal with respect to the upper surface of the roller table on which the web of the rolled material conveys the rolled material. A method for producing a T-shaped steel, in which the lower end is inclined to a state of the same height, in any inclined state of the web, cooling by at least one of the outer surface and the inner surface of the flange by water cooling. The method of claim 10,
In the finish rolling mill, the front end of the web and the lower end of the flange have the same height from the front surface of the finish rolling mill, with the web of the rolled material being substantially horizontal with respect to the upper surface of the roller table for conveying the rolled material. In the case of inclining to, in any inclined state of the web, cooling is performed by water cooling toward at least one of the outer surface and the inner surface of the flange.

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