KR102599706B1 - Guide to the steel plate rolling mill and manufacturing method of the steel plate - Google Patents

Abstract

Provided is a guide for a steel plate rolling mill and a method for manufacturing a steel plate, which can suppress the occurrence of guide clogging and guide scratches and has excellent maintainability. A hollow shape (e.g., K2 hollow shape 71) according to the shape of the steel sheet 1 is formed at the entrance of a rolling mill (e.g., a finishing rolling mill 6) having an upper roll and a lower roll that are stamped. As the guide 8 of the commercially available rolling mill (1), the hollow shape is a shape seen from the rolling direction and includes a first portion 711 for rolling a web and a pair of second portions for rolling a pair of flat points ( 712), each formed on the first portion 711 side of the pair of second portions 712 when viewed from the rolling direction, and at least one roller 812 rotatable in the rolling direction, the material to be rolled. a pair of roller guides 81 that guide the flat point of the ball in a ball shape, and are formed on the side of the pair of second parts 712 of the first part 711 when viewed from the rolling direction, and guide the web of the material in a ball shape. A guiding web guide (82) is provided.

Description

Guide to the steel plate rolling mill and manufacturing method of the steel plate

The present invention relates to a guide for a steel plate rolling mill and a method for manufacturing a steel plate.

Steel plates such as hat-shaped steel plates are used as embankment members in civil engineering work, for example. The hat-shaped steel plate has features such as an effective width of 900 mm, a left-right asymmetric joint shape, and a fitting portion located at the outermost edge of the wall. From this, compared to the conventional 600 mm wide steel sheet (hereinafter also referred to as 600 width steel sheet), there are advantages such as shortening the work period and improving the rigidity as a wall, and the hat-shaped steel sheet can be changed from the 600 mm wide steel sheet. Varieties replacement is in progress.

〈Problem of stretching and defective appearance〉

However, when hot rolling the above ultra-wide and asymmetrically shaped hat-shaped steel sheet, the rolling load and temperature deviation in the width direction increase compared to the conventional steel sheet, so the engagement posture at the front of the rolling mill Unstable phenomena such as stretching or appearance defects due to deterioration of the product are likely to occur. Here, sticking refers to a shape defect that occurs when the rolled material is bitten by a roll, causing a part of the rolled material to peel off and be pressed against the roll due to misalignment in the width direction or vertical direction, and the pressed portion is transferred to the surface of the rolled material. . Also, appearance defects that appear include bending of the rolled material in the width direction, bending or twisting in the vertical direction, etc., which causes the rolled material to line out, or to a state where it cannot proceed to the next pass, and rolling is stopped.

Regarding this problem, for example, in Patent Document 1, a first guide in contact with the web and the flange, a second guide sandwiching the web between the first guide, and an arm are provided on each of the entry and exit sides of the rolling mill. A method of stabilizing the biting posture and appearance by arranging a third guide that restrains the part from above and below is disclosed.

Japanese Patent Publication No. 2009-119513

However, in the method disclosed in Patent Document 1, a plurality of friction guides are arranged on each of the entry and exit sides of the rolling mill and the rolled material is excessively restrained in the vertical direction, so there is a possibility of guide clogging or guide scratches occurring. there is. Additionally, since there are many installation points of the guide at the top and bottom of the web, inside the corner portion of the web and the flange, and the top and bottom of the arm portion, the guide structure becomes complicated and maintenance becomes difficult.

Therefore, the present invention was made with attention to the above problems, and its purpose is to provide a guide for a steel plate rolling mill and a method for manufacturing a steel plate, which can suppress the occurrence of guide clogging and guide scratches and has excellent maintainability. It is being done.

According to one aspect of the present invention, a web having a cross-sectional shape perpendicular to the longitudinal direction and extending in one direction, a pair of flanges connected to both ends of the web in the one direction and extending at an angle with respect to the one direction; , in the rolling of a steel plate having a pair of flat portions connected to the end of the pair of flanges on the side to which the web is not connected and having a flat point extending in the one direction, according to the shape of the steel plate A guide for a steel sheet rolling mill, which is formed at the entrance of a rolling mill having an upper roll and a lower roll in which a ball shape is engraved, wherein a web corresponding part corresponding to the web in the material to be rolled is restrained from one direction in the vertical direction to be held in the ball shape. A pair of roller guides having a guiding web guide and one or more rollers rotatable in the rolling direction, restraining a flat portion corresponding to the flat portion of the material from the other vertical direction and guiding it to the ball shape. A guide for a steel plate rolling mill is provided.

According to one aspect of the present invention, a web having a cross-sectional shape perpendicular to the longitudinal direction and extending in one direction, a pair of flanges connected to both sides of the web and extending obliquely with respect to the one direction, and the 1 When rolling a steel plate having a pair of flat portions connected to opposite sides of the web of a pair of flanges and having a flat point extending in the one direction, at the entrance of the rolling mill having a hollow shape according to the shape of the steel plate, A method of manufacturing a steel sheet is provided, which includes a rolling process of installing a guide to the rolling mill of the steel sheet and performing rolling using the rolling mill.

According to one aspect of the present invention, a guide for a steel plate rolling mill and a method for manufacturing a steel plate are provided, which can suppress the occurrence of guide clogging and guide scratches and have excellent maintainability.

Fig. 1 is a schematic diagram showing the cross-sectional shape of a hat-shaped steel plate.
Fig. 2 is an explanatory diagram showing the equipment configuration of the rolling equipment.
Figure 3 is a partial cross-sectional view showing a finishing rolling mill.
Fig. 4 is a front view showing a guide formed in a finishing rolling mill.
FIG. 5 is a cross-sectional view seen from the arrow on line AA' in FIG. 4.
Figure 6 is a schematic diagram showing the cross-sectional shape of a U-shaped steel plate.

In the following detailed description, numerous specific details are set forth by way of illustration to provide a thorough understanding of the invention. However, it is clear that one or more embodiments may be practiced without these specific details. In addition, in the drawings, for the sake of brevity, well-known structures and devices are shown as schematic diagrams.

＜Rolling equipment＞

With reference to FIGS. 1 and 2, a rolling facility according to an embodiment of the present invention will be described. The rolling equipment 2 is equipment that manufactures the steel plate 1 by rolling a rectangular slab or the like as a raw material using a plurality of rolling mills. In this embodiment, the steel plate 1 manufactured is a hat-shaped steel plate 1A whose constant cross-sectional shape orthogonal to the longitudinal direction is hat-shaped, as shown in FIG. 1 . The hat-shaped steel plate 1A has a web 11, a pair of flanges 12, a pair of arm portions 13, and a pair of joint portions 14 in cross-sectional shape. The web 11 is a portion extending in one direction (left-right direction in FIG. 2, hereinafter also referred to as “left-right direction”). A pair of flanges 12 is a portion that is connected to both ends of the web 11 in the left and right directions and extends obliquely with respect to the left and right directions. In the example shown in FIG. 1, the pair of flanges 12 extend obliquely so that the end on the opposite side of the web 11 is on the lower side in the vertical direction (the vertical direction in FIG. 1, the direction orthogonal to the left and right direction). . The pair of arm portions 13 are portions that are connected to the side of the pair of flanges 12 to which the web 11 is not connected and extend in the left and right directions. The pair of joint portions 14 are portions of the pair of arm portions 13 connected to the side to which the flange 12 is not connected, and have a hook-like shape that opens upward or downward in the vertical direction. When used as a steel plate, a pair of joint portions 14 are parts used for connection with another steel plate by fitting into the joint portion of another steel plate. In addition, in this embodiment, the arm portion 13 and the joint portion 14 are also collectively referred to as the flat portion 15. The flat portion 15 is a portion of the steel plate 1 that is formed by connecting to the end of the flange 12 on the side to which the web 11 is not connected, and has a flat point extending in the left and right directions. In this embodiment, the arm portion 13 serves as a flat point in the flat portion 15. In addition, the distance between a pair of seams 14 shown by W in FIG. 1 is called the effective width, and the distance in the vertical direction from the flange 12 shown by H in FIG. 1 to the arm section 13 is called the effective height. do.

As shown in Fig. 2, in the rolling equipment 2, a rectangular slab, which is a material heated to a predetermined temperature in the heating furnace 3, is processed into a rough rolling mill (BD) 4 and an intermediate rolling mill (SR) 5. ) and a finishing mill (SF) 6, the hat-shaped steel sheet 1A is manufactured by sequential rolling.

The rough rolling mill 4 roughly shapes the rectangular slab heated in the heating furnace 3 into a shaped steel piece whose cross-section perpendicular to the longitudinal direction is approximately hat-shaped. The rough rolling mill 4 has one roll set consisting of an upper roll and a lower roll. This roll set is stamped with a plurality of balls called calibers (for example, Box balls, K8 balls, and K7 balls).

The intermediate rolling mill 5 is for rolling the material rolled by the rough rolling mill 4 and has two sets of rolls each having a plurality of hollow shapes. For example, in each roll set of the intermediate rolling mill 5, two balls are stamped, and a total of four balls are stamped (for example, K6 balls to K3 balls). Here, for example, when a Box die, a K8 die to a K3 die is formed in the rough rolling mill 4 and the intermediate rolling mill 5, the Box die has a hollow shape (shape of the roll gap) viewed from the rolling direction of approximately It becomes a square shape, and for the K8 hole shape to the K3 hole shape, the ball shape seen from the rolling direction is a hat shape. In addition, for the K8 die to the K3 die, the roll gap and shape are set so that the later the die is used in the rolling process, the thinner the sheet thickness of the material being rolled becomes, and the cross-sectional shape becomes closer to the shape of the product.

The finishing mill 6 rolls the material rolled by the intermediate rolling mill 5 and has one roll set in which two balls are stamped. In short, the finishing mill 6 has two hollow dies, and these hollow dies are called the K2 hollow mold and the K1 hollow mold.

The finishing mill 6 will be described in detail with reference to FIG. 3 . As shown in FIG. 3 , the finishing mill 6 is one roll set and has an upper roll 61 and a lower roll 62 that are arranged to face each other in the vertical direction, which is the vertical direction. On the upper roll 61 and the lower roll 62, a K2 hollow shape 71 and a K1 hollow shape 72 according to the product shape of the hat-shaped steel plate 1A are stamped. The K2 die 71 is a die for rolling the material so that the plate thickness becomes the product thickness with respect to the cross-sectional shape of the material rolled by the intermediate rolling mill 5. The K1 die 72 is a die for bending and forming the joint portion 14 of the material rolled by the K2 die 71. In addition, in the K2 ball shape 71, the area where the web 11 of the hat-shaped steel plate 1A is rolled is referred to as the first area 711, and the arm section 13, which is the flat point of the flat section 15, is referred to as the first section 711. The area where the flange 12 is rolled is referred to as the second area 712, and the area where the flange 12 is rolled is referred to as the third area 713. In short, the K2 ball shape 71 is the shape of the roll gap (gap between the upper roll 61 and the lower roll 62) seen from the rolling direction, and includes a first portion 711, a second portion 712, It has a third portion (713).

On the upstream side of the K2 die 71 of the finishing mill 6 (upstream in the rolling direction, the entry side where the material enters the finishing mill 6), there is a guide 8 that guides the material to be rolled to the K2 die 71. ) is installed. As shown in FIGS. 4 and 5, the guide 8 includes a pair of roller guides 81, a web guide 82, an upper rest bar 83, and a lower rest bar 84. .

One pair of roller guides 81 each has a guide frame 811 and two rollers 812. A pair of roller guides 81 are guides that restrain the area along the arm portion, which is the flat point of the material to be rolled, from the upper side and guide it to the K2 ball 71. In order to guide the flat point of the material, the pair of roller guides 81 are positioned above the pair of second portions 712 when viewed from the rolling direction, that is, in a direction perpendicular to the extension direction of the second portion 712. are formed on the first portion 711 side, respectively.

The guide frame 811 is a member that supports the two rollers 812 and is fixed to the upper rest bar 83. As shown in FIG. 5, the guide frame 811 has an obliquely notched shape with respect to the end on the upstream side of the rolling direction (left side in FIG. 5) so that the lower end is located on the upper side as it moves toward the upstream side of the rolling direction. have With such a shape, the material can be guided to the K2 ball 71 even when the upper bend of the tip of the rolled material is large. The two rollers 812 are fixed to the guide frame 811 in a state that can rotate in the rolling direction of the material to be rolled, and are installed aligned in the rolling direction.

As shown in FIG. 4, the pair of roller guides 81 are located on the first portion 711 side (toward the web side of the hat shape) of the second portion 712 of the K2 ball 71 when viewed from the rolling direction. 4, respectively) are placed on the upper side. A pair of roller guides 81 is provided so that the lower ends of the two rollers 812 are above the roll gap between the upper roll 61 and the lower roll 62 when viewed from the rolling direction. It is preferable that a predetermined clearance d2 is provided in the roller 812 and the second portion 712 of the K2 ball 71. As shown in FIG. 4, the clearance d2 is the upper end of the roll gap between the lower end of the roller 812 and the second portion 712 of the K2 ball 71 (of the upper roll 61) when viewed from the rolling direction. (bottom) is the distance in the vertical direction. The clearance d2 is a predetermined distance, which is the distance of the roll gap in the second area 712 of the K2 die 71, and is the distance between the roll gaps in the second area 712 in the final rolling pass in the K2 die 71. It is preferable that the separation distance (roll clearance distance) between the upper roll 61 and the lower roll 62 is approximately the same. Here, the final rolling pass is the last rolling pass performed when rolling is performed in multiple passes in the die, and is the 1 pass in which rolling is performed when only 1 pass is rolled in the die. In short, the distance between the rolls in the final rolling pass is equal to the thickness of the material rolled in the die after rolling. In addition, the clearance d2 is preferably a distance of 40% or more and 120% or less of the distance of the roll gap at the second portion 712 of the K2 hollow mold 71, and It is preferred that it is the same as the distance of the roll gap at (712). In addition, the roll gap in the second portion 712 of this K2 ball 71 corresponds to the plate thickness of the arm portion 13 of the hat-shaped steel plate 1A to be rolled. When the clearance d2 is less than 40% of the distance of the roll gap in the second portion 712 of the K2 hollow mold 71, the clearance d2 is too small, and the possibility of clogging of the material increases. On the other hand, when the clearance d2 is more than 120% of the distance of the roll gap in the second portion 712 of the K2 hollow shape 71, the clearance d2 is too large, and the material is not guided to the roll gap, There is a possibility that a defective bite may occur.

The web guide 82 has a shape along the first portion 711 and the third portion 713 of the K2 hollow shape 71 when viewed from the rolling direction, that is, the web 11 of the hat-shaped steel plate 1A and It is a friction guide having a shape along the flange (12). The web guide 82 restrains the portion corresponding to the web and flange of the material to be rolled from the lower side and guides it to the K2 ball 71. As shown in FIG. 5 , the web guide 82 has an obliquely notched shape so that the upper end is located lower as it becomes upstream in the rolling direction, with respect to the end portion on the upstream side of the rolling direction. With such a shape, the material can be guided to the K2 ball 71 even when the downward bending of the tip of the rolled material is large.

In addition, the web guide 82 is below the first portion 711 and the third portion 713 of the K2 ball 71, that is, orthogonal to the extension direction of the first portion 711 when viewed from the rolling direction. It is disposed on the second portion 712 side (toward the hat-shaped arm portion, lower side in FIG. 4).

When viewed from the rolling direction, the web guide 82 has its upper end positioned below the roll gap between the upper roll 61 and the lower roll 62, and is positioned between the web guide 82 and the K2 ball shape 71. It is preferable that predetermined clearances d1 and d3 are provided in the first portion 711 and the third portion 713, respectively. As shown in FIG. 4, the clearance d1 is the upper end of the point corresponding to the web of the web guide 82 and the lower end of the roll gap of the first portion 711 (lower roll 62), as seen from the rolling direction. (top of ) is the distance in the vertical direction. The clearance d3 is the upper end of the point corresponding to the flange of the web guide 82 when viewed from the rolling direction (the point at the top that extends diagonally to the left and right directions when viewed from the rolling direction) and the section of the K2 hollow shape 71. It is the distance in the perpendicular direction of the third portion 713 from the lower end of the roll gap of the third portion 713 (the upper end of the lower roll 62). In addition, the clearance d1 is a distance of 40% or more and 120% or less of the distance of the roll gap in the first portion 711 of the K2 ball 71, and the clearance d3 is a distance in the third portion 713. It is preferable that the distance is 60% or more and 180% or less of the distance between the rolls. In addition, the roll gap in the first portion 711 and the third portion 713 of this K2 ball 71 is between the web 11 and the flange 12 of the product of the hat-shaped steel plate 1A to be rolled. Each corresponds to the plate thickness. By setting the clearances (d1, d3) to the above range, the same effect as the clearance (d2) is obtained.

The upper rest bar 83 is a member that supports a pair of roller guides 81 and is formed to extend in the left and right directions. The upper rest bar 83 is fixedly installed to the housing or chock of the rolling mill where the guide 8 is installed. In addition, the upper rest bar 83 is formed above the K2 ball shape 71 when viewed from the rolling direction, and the guide frame 811 of the pair of roller guides 81 is fixed thereto.

The lower rest bar 84 is a member that supports the web guide 82 and is formed to extend in the left and right directions. The lower rest bar 84 is fixedly installed to the housing or chock of the rolling mill where the guide 8 is installed. Additionally, the lower rest bar 84 is formed below the K2 hollow shape 71 when viewed from the rolling direction, and the web guide 82 is fixed thereto.

＜Manufacturing method of steel plate＞

Next, the manufacturing method of the steel sheet 1 according to the present embodiment will be described. In this embodiment, the rectangular slab heated to a predetermined temperature in the heating furnace 3 is sequentially rolled in the rough rolling mill 4, the intermediate rolling mill 5, and the finishing mill 6 to obtain a cross-sectional shape shown in FIG. 1. A hat-shaped steel sheet (1A) is manufactured. In addition, the process of performing rolling with each rolling mill is also called a rolling process.

In rolling in the rough rolling mill 4 and the intermediate rolling mill 5, the material is rolled multiple times in each die of each rolling mill. Additionally, in the rough rolling mill (4), when using the Box die as described above, the width reduction of the rectangular slab is performed with the Box die, and then the bending forming and thickness reduction of the slab are sequentially performed with the K9 die. do.

In rolling in the finishing mill 6, the material rolled in the intermediate rolling mill 5 is rolled in the K2 die 71 and then in the K1 die 72. At this time, the number of rolling passes in the K2 die 71 and the K1 die 72 is set to 1 pass.

In rolling in the K2 die 71, the material is clamped into the K2 die 71 through the guide 8. At this time, the material is restrained from the upper side by a pair of roller guides 81 and is restrained from the lower side by the web guide 82. This makes it possible to maintain the engagement posture of the material with the K2 ball 71 within a predetermined range, and even when the material has an upper deflection greater than the clearance d1 or a lower deflection greater than the clearance d3, the material The tip of can be clamped into the K2 ball shape (71). Additionally, since the material is restrained in the left and right directions by the web guide 82, the engagement posture with the K2 ball 71 is maintained in a predetermined range depending on the clearance d2. For this reason, even when the material has bends in the left and right directions, the tip of the material can be clamped into the K2 ball shape.

＜Modification example＞

In the above, the present invention has been described with reference to specific embodiments, but it is not intended to limit the invention to these descriptions. By referring to the description of the present invention, other embodiments of the present invention including various modifications along with the disclosed embodiments are also apparent to those skilled in the art. Accordingly, it should be understood that the embodiments of the invention described in the patent claims also include embodiments including these modifications described in the present specification singly or in combination.

For example, in the above embodiment, the steel plate 1 is a hat-shaped steel plate 1A, but the present invention is not limited to this example. The steel plate 1 may have a different cross-sectional shape as long as it has a web, a flange, and a flat portion that is a flat portion. For example, the steel plate 1 may be a U-shaped steel plate 1B with a cross-sectional shape shown in FIG. 6 . The U-shaped steel plate 1B is a steel plate whose cross-sectional shape is U-shaped, and as shown in FIG. 6, it includes a web 11, a pair of flanges 12, and a pair of joint portions 14. have The web 11 and the pair of flanges 12 are the same as those of the hat-shaped steel plate 1A. The pair of joint portions 14 are portions of the pair of flanges 12 that are connected to the side to which the web 11 is not connected, and as shown in FIG. 6, has a flat portion extending in the left and right directions at the bottom. It is to have. In such a U-shaped steel plate 1B, a flat portion (claw bottom portion 142 in FIG. 6) corresponding to the flat portion 15 in the above embodiment is present in the joint portion 14. Since the bottom portion 142 is restrained from the upper side by the same pair of roller guides as in the above embodiment, the engagement posture is stabilized. In addition, in the present invention, in the ball mold in which the guide is formed, the second portion is the portion of the roll gap where the claw bottom portion 142 is rolled. For this reason, in the case of the U-shaped steel plate 1B, the hollow second portion becomes a portion of the roll gap for rolling the claw bottom portion 142 extending in the left and right direction of the joint portion. The cross-sectional shape of the U-shaped steel plate 1B shown by the solid line in FIG. 6 represents the cross-sectional shape after the final rolling (rolling using the K1 die), but it is one rolling before the final rolling (in the die before the K2 die). In rolling), the claws 141 of the joint portion 14 are rolled in an outwardly open shape as indicated by the broken line, so the clearance d2 is set as described above to form the roller 812. By doing so, the claw bottom portion 142 is guided into a ball shape by the roller 812.

In addition, in the above embodiment, two rollers 812 are formed in the roller guide 81, but the present invention is not limited to this example. There may be at least one roller 812 formed on one roller guide 81.

In addition, in the above embodiment, the web guide 82 is assumed to be a friction guide, but the present invention is not limited to this example. The web guide 82 may be a roller guide in which rollers are formed at points in contact with the web or flange as the material. In this case, the roller may be the same as the roller 812 in the roller guide 81.

In addition, in the above embodiment, the direction of the steel sheet 1 to be rolled is such that the web 11 is on the upper side in the vertical direction and the flat portion 15 is on the lower side in the vertical direction. However, the present invention is not limited to this example. . For example, the direction of the steel sheet 1 to be rolled may be opposite to that of the above-mentioned embodiment in the vertical direction. In this case, the direction in which the roller guide 81 and the web guide 82 restrain the material is vertically opposite to that of the above embodiment.

In addition, in the above embodiment, the guide 8 is installed in the K2 cavity 71 of the finishing mill 6, but the present invention is not limited to this example. For example, the guide may be formed in the K1 die 72 of the finishing mill 6 or another die in the rough rolling mill 4 or the intermediate rolling mill 5. In this case, in the case of a rolling mill that performs reverse rolling in which the rolling direction changes as a multiple-pass rolling, such as the rough rolling mill 4 or the intermediate rolling mill 5, guides 8 are formed on both sides of the conveyance direction of the roll set. It's okay.

＜Effects of the embodiment＞

(1) The guide 8 of the rolling mill of the steel plate 1 according to one aspect of the present invention has a cross-sectional shape perpendicular to the longitudinal direction, and includes a web 11 extending in one direction, and one of the webs 11. A pair of flanges 12 connected at both ends in one direction and extending diagonally in one direction, and a web 11 of the pair of flanges 12 connected to the end of the side that is not connected, and extending in one direction. In the rolling of a steel sheet 1 having a pair of flat portions 15 with extending flat points, a hollow shape (for example, a K2 hollow shape 71) according to the shape of the steel sheet 1 is stamped and formed. A guide 8 for the rolling mill of the steel sheet 1, formed at the entrance of a rolling mill (for example, a finishing mill 6) having an upper roll and a lower roll, corresponding to the web 11 in the material to be rolled. It has a web guide 82 that restrains the web corresponding portion from one direction in the vertical direction and guides it in a ball shape, and one or more rollers 812 rotatable in the rolling direction, and moves the flat portion corresponding to the flat portion in the material up and down. It is provided with a pair of roller guides 81 that are constrained from the other direction and guided in a ball shape.

According to the configuration of (1) above, the material to be rolled can be restrained in the vertical direction at the entrance of the rolling mill. For this reason, even when there is vertical bending or twisting in the material, the material is sent to the rolling mill in an appropriate engagement posture, and the occurrence of engagement defects can be prevented. In addition, the guide 8 of the configuration of (1) above includes a pair of roller guides 81 on the entrance side of the rolling mill that restrain the flat spot from one direction in the vertical direction, and a web 11 from the other direction in the vertical direction. ) is composed only of the web guide (82) that restrains the material, making it possible to bite the material into a ball shape. For this reason, compared to guides that constrain both the entry and exit sides of the rolling mill or a large number of points in the cross section of the material, as in Patent Document 1, the restraint is not excessive, preventing guide clogging where the material gets stuck in the guide. , the occurrence of guide scratches caused by contact with the guide can be suppressed. Additionally, in the configuration of (1) above, compared to the guide in Patent Document 1, the number of configurations that restrain the guide can be reduced, resulting in excellent maintainability. In addition, in the configuration of (1) above, at least the roller guide 81 is a guide mechanism using rollers. As a result, the configuration of (1) above has excellent maintainability compared to the friction type guide mechanism. Additionally, because it is a guide mechanism using rollers, the occurrence of guide scratches can be further suppressed compared to a friction-type guide mechanism. In addition, by stabilizing the engagement posture, it is possible to suppress the occurrence of defects such as twisting or vertical bending during hot rolling, guide scratches, and sticking.

(2) In the configuration of (1) above, a predetermined clearance d2 is formed between the roller 812 and the upper or lower end of the ball shape when viewed from the rolling direction.

According to the configuration of (2) above, the occurrence of guide clogging can be further suppressed.

(3) In the configuration of (2) above, the clearance d2 is 40% or more and 120% or less of the distance between the roll gaps between the upper roll and the lower roll at the point where the flat portion corresponding portion is rolled in the ball shape. .

According to the configuration of (3) above, the occurrence of guide clogging and occurrence of engagement defects can be further reduced.

(4) In the structure of any one of the above (1) to (3), the steel plate 1 is a pair of flat portions 15, connected to a pair of flanges 12, and extends in one direction. A hat-shaped steel plate ( 1A), and the pair of flat portions 15 are a pair of arm portions 13.

According to the configuration of (4) above, in the hat-shaped steel sheet, which is ultra-wide and has an asymmetrical shape, and whose engagement posture is likely to deteriorate due to the rolling load or temperature deviation in the width direction, the engagement posture can be stabilized. You can.

(5) A method of manufacturing a steel sheet 1 according to an aspect of the present invention includes a web 11 extending in one direction, with a cross-sectional shape perpendicular to the longitudinal direction, and connected to both sides of the web 11, A pair of flanges (12) extending obliquely in one direction, and a pair of flanges (12) connected to the side to which the web (11) is not connected, and having a flat point extending in one direction. When rolling the steel plate 1 having the flat portion 15, the steel plate according to any one of (1) to (4) above is placed on the entrance side of the rolling mill having a hollow shape according to the shape of the steel plate 1. (1) There is a rolling process in which the guide of the rolling mill is installed and rolling is performed with the rolling mill.

According to the configuration (5) above, the same effect as the configurations (1) to (4) above is obtained.

Example

Next, an embodiment implemented by the present inventors will be described. In the examples, as in the above embodiment, a hat-shaped steel plate 1A having an effective width W of 900 mm and an effective height H of 230 mm was manufactured using the rolling equipment 2 shown in FIG. 2. . At this time, a guide 8 was installed on the entrance side in the rolling direction in the K2 hollow die 71 where final thickness reduction was performed. In the guide 8, the dimensions of the roller 812 are 170 mm in diameter and 60 mm in width, and the clearances d1 to d3 are the roll clearance in the first area 711 to the third area 713. It was equal to the distance of . Then, 10 materials are continuously rolled in the rolling equipment (2), and the presence or absence of guide clogging, the occurrence of appearance defects, the occurrence of sagging, and the occurrence of guide scratches are checked in the K2 ball mold (71). The presence or absence of occurrence was confirmed.

In addition, as a comparison, the conditions in which rolling was performed without installing the guide 8 using the same rolling equipment as in the examples (Comparative Example 1), and the conditions in which rolling was performed with a guide simulating Patent Document 1 installed (Comparative Example 2) ) was also rolled, and the presence or absence of abnormalities in the K2 ball 71 was confirmed in the same manner as in the Example.

Table 1 shows the results of Examples and Comparative Examples 1 and 2. Additionally, in Table 1, “rolling order” indicates the 10 rolled materials. In addition, in Table 1, regarding the results of occurrence of an abnormality, “○” indicates that the respective abnormality did not occur, “×” indicates that the respective abnormality occurred, and “-” indicates that the presence or absence of the occurrence could not be confirmed. In addition, sticking refers to a shape defect that occurs when a material is bitten by a roll, a part of the material is peeled off and pressed against the roll due to misalignment in the width direction or the vertical direction, and the pressed portion is transferred to the surface of the material. In addition, the aspect defect that appears is that the material is bent in the width direction, bent in the vertical direction, twisted, etc., resulting in line out, or is in a state where it cannot proceed to the next pass, and rolling is stopped. Additionally, guide scratches are shape defects that occur on the surface of a material due to strong contact with the guide. In this example, after inspecting the shape of each material, the next material was rolled. In addition, when sticking was confirmed in the shape inspection, each roll of the intermediate rolling mill 5 and the finishing mill 6 was inspected, and the rolls were trimmed using a grinder.

As shown in Table 1, in Comparative Example 1, aspect defects and sagging that appeared in the early stages of rolling occurred. In addition, sticking occurred sporadically even after rolling adjustment by adjusting the inclination of the roll, etc. Additionally, in Comparative Example 2, guide clogging occurred in the first rolling, but no defects in appearance occurred. Additionally, although guide scratches occurred at the beginning of rolling, the guide scratches disappeared after adjustment.

In contrast, in the examples, there was no guide clogging, appearance defects, sticking, or guide scratches from the first piece, and the improvement effect was confirmed.

In addition, the present inventors also performed rolling in the intermediate rolling mill 5 under the conditions of installing the same guide as in the finishing mill 6. As a result, it was confirmed that rolling could be performed even during rolling using the intermediate rolling mill 5 without abnormalities such as guide clogging, appearance defects, sticking, or guide scratches occurring.

One ; Kang Si-pan
1A ; Hat-shaped steel plate
1B ; U-shaped steel plate
11 ; web
12 ; flange
13 ; arm part
14 ; seam
15 ; flat part
2 ; rolling equipment
3 ; heating furnace
4 ; roughing mill
5 ; middle rolling mill
6 ; finishing mill
61 ; upper roll
62 ; lower roll
71 ; K2 ball type
711 ; part 1
712 ; second part
713 ; third part
8 ; guide
81 ; roller guide
811 ; guide frame
812 ; Roller
82 ; web guide
83 ; upper rest bar
84 ; lower rest bar

Claims (5)

A web having a cross-sectional shape perpendicular to the longitudinal direction, extending in one direction, a pair of flanges connected to both ends of the web in the one direction and extending obliquely with respect to the one direction, and the pair of flanges In the rolling of a steel plate having a pair of flat portions connected to an end of the side to which the web is not connected and having a flat point extending in the one direction, an upper roll having a hollow shape according to the shape of the steel plate is engraved; As a guide for a steel plate rolling mill formed at the entrance of a rolling mill having a lower roll,
A web guide that restrains a web corresponding part corresponding to the web in a material to be rolled from one vertical direction and guides it to the ball shape;
A pair of roller guides having one or more rollers rotatable in the rolling direction and restraining a flat portion corresponding to the flat portion of the material from other directions in the vertical direction and guiding it to the ball shape.
A guide for a steel plate rolling mill provided with a. According to claim 1,
A guide for a steel plate rolling mill, wherein a predetermined clearance is formed between the roller and the upper or lower end of the ball shape when viewed from the rolling direction. According to claim 2,
The clearance is 40% or more and 120% or less of the distance between the roll gap between the upper roll and the lower roll at the point where the flat portion corresponding portion is rolled in the ball shape. A guide for a steel plate rolling mill. The method according to any one of claims 1 to 3,
The steel plate is the pair of flat portions, and is connected to the pair of flanges, and includes a pair of arm portions extending in one direction, and the pair of flanges of the pair of arm portions. A hat-shaped steel plate having a joint connected to the side that is not exposed,
The pair of flat parts is a guide for a steel sheet rolling mill, which is the pair of arm parts. A cross-sectional shape perpendicular to the longitudinal direction, comprising a web extending in one direction, a pair of flanges connected to both sides of the web and extending diagonally with respect to the one direction, and the web of the pair of flanges connected. When rolling a steel plate having a pair of flat portions connected to the side that is not connected and having a flat point extending in the one direction,
A guide for the rolling mill of the steel plate according to any one of claims 1 to 3 is installed at the entrance of a rolling mill having a hollow shape according to the shape of the steel plate, and a steel plate having a rolling process of rolling with the rolling mill. Commercially available manufacturing method.