Rolling method and rolling equipment for shapes

Abstract

To provide a rolling method and a rolling facility for a shape material which can suppress the material from bending appropriately, in accordance with a form of the bending.SOLUTION: In a shape material manufacturing method for manufacturing shape materials continuously by making a rolling machine sequentially roll a plurality of raw materials, amounts of bending of shape materials manufactured using the rolling machine and a pair of rolling guides 52 that guides in a lateral direction, the shape materials rolled by the rolling machine are measured by a bending measurement device 53 to determine amounts of bending in a first region R1 and in a second region R2 at a downstream side in a conveying direction of the shape materials; amounts of change of at least either of a rolling condition for a roll gap of the rolling machine and a guide condition for a forward / backward movement position of the rolling guide 52 are calculated, in accordance with a shape of bending of the first region and a shape of bending of the second region; and rolling is performed under the rolling condition and the guide condition which are adjusted by the calculated amounts of change.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a rolling method and rolling equipment for a section bar. [Background technology]

[0002] When rolling H-beam steel, which is a shaped material, three rolling processes are carried out: rough rolling, intermediate rolling, and finish rolling. Of these, in the rough rolling process, a slab, bloom, or beam blank heated to a predetermined temperature in a heating furnace is used as the material, and rolled in a rough rolling mill to form a roughly H-shaped raw steel billet with a web and flanges on both ends.

[0003] In the intermediate rolling process, the thickness of the web and flange of the rough steel billet is reduced by rolling using an intermediate universal rolling mill. Furthermore, in the intermediate rolling process, the width of the flange is reduced by rolling using an edging rolling mill used in combination with the intermediate universal rolling mill. In this intermediate rolling process, multiple passes of reverse rolling are performed.

[0004] Furthermore, in the finish rolling process, a finishing universal rolling mill incorporating a pair of upper and lower horizontal rolls and a pair of left and right vertical rolls is typically used, and one pass of finish rolling is performed. In the finish rolling process, the thickness of the web is reduced by the peripheral surfaces of the pair of upper and lower horizontal rolls, and the thickness of the flange is reduced and the angle of the flange is corrected by the peripheral surfaces of the side of the horizontal roll and the vertical rolls located on the left and right of the horizontal roll, thereby producing H-beams of the product dimensions. The H-beams of the product dimensions are then cut to the specified product length by a hot sawing machine or a cold sawing machine.

[0005] Incidentally, H-beam products can suffer from shape defects known as "bending," where the product bends to the left or right in the longitudinal direction, as shown in Figure 6. A tolerance range is set for bending; for example, the JIS standard (JIS G3192) stipulates that the amount of bending δ defined in Figure 6 must be 0.001 or less of the product length (when the web height H exceeds 300 mm). If the bending falls outside this tolerance range, it must be corrected using a press straightening machine or similar. If the bending does not fall within the tolerance range even after further correction, the product is rejected, which is a major obstacle to productivity.

[0006] Several methods for improving this bending have been proposed. For example, Patent Document 1 discloses a technique in which the amount of bending in the height direction of the section steel (referred to as "warpage" in Patent Document 1) is measured along the length direction of the rolled material at the delivery side of a universal rolling mill during rolling, and the roll offset amount in the pass line direction between the left and right vertical rolls of the universal rolling mill is adjusted based on the measured amount of bending.

[0007] Furthermore, Patent Document 2 discloses a technology in which the thicknesses of the left and right flanges before rolling are determined, an amount of change from a reference position of the vertical roll position at which the difference in the left and right flange thicknesses is eliminated after rolling is calculated, an amount of bending after rolling that is predicted to occur due to a difference in the reduction ratio of the left and right flange thicknesses when rolling is performed according to this amount of change, an amount of change from a reference position of the guide position at which this amount of bending is eliminated is calculated, and rolling is performed by correcting the vertical roll position and guide position in the rolling mill based on these amounts of change.

[0008] Furthermore, Patent Document 3 discloses a technology in which entry-side constraint rollers are arranged on each of the entry and exit sides of a universal rolling mill, facing the outer surfaces of the flanges and able to move freely toward and away from the outer surfaces of the flanges, and whose cross-sectional contour shape on the entry side is substantially the same as the cross-sectional shape of the outer surfaces of the flanges of the H-beam before rolling, and exit-side constraint rollers are arranged on the exit side, whose cross-sectional contour shape is substantially the same as the cross-sectional shape of the outer surfaces of the flanges of the H-beam after rolling, and the widthwise center positions of the entry-side constraint rollers and exit-side constraint rollers are made to substantially coincide with the widthwise center positions of a pair of left and right vertical rolls, and these entry-side constraint rollers and exit-side constraint rollers are brought into contact with substantially the entire outer surfaces of both flanges to constrain the flanges while rolling the H-beam, thereby suppressing bending of the H-beam. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 10-225708 [Patent Document 2] Japanese Patent Application Laid-Open No. 2001-30003 [Patent Document 3] Japanese Patent Application Laid-Open No. 2000-140925 Summary of the Invention [Problem to be solved by the invention]

[0010] The bending suppression technology disclosed in Patent Document 1 requires adjusting the offset of the vertical rolls of a universal rolling mill according to the measured amount of bending. However, bending often changes very sensitively to this adjustment, and there is a problem that bending cannot be accurately controlled due to an error in the amount of change during adjustment. There is also a problem that it cannot handle S-shaped bending, where the bending direction changes in the longitudinal direction.

[0011] Furthermore, the bending suppression technology disclosed in Patent Document 2 requires accurate determination of flange thickness before and after rolling, and also requires calculation using a model formula to predict bending after rolling. Therefore, there is a problem that bending cannot be accurately controlled in many cases due to errors in the calculation of flange thickness and errors in the model formula. Also, as with Patent Document 1, there is a problem that it cannot handle S-shaped bending, where the bending direction changes in the longitudinal direction.

[0012] Furthermore, in the bending suppression technology disclosed in Patent Document 3, it is necessary to accurately set the restraining rollers installed on the front and rear surfaces of the universal rolling mill in order to suppress bending. If the set positions are misaligned even slightly, the bending correction effect cannot be achieved, and depending on the direction of the misalignment, there is a problem that the bending may actually become larger. Therefore, the present invention has been made in consideration of the above-mentioned problems, and aims to provide rolling equipment and a rolling method for shape bars that can appropriately suppress bending depending on the type of bending. [Means for solving the problem]

[0013] (1) According to one aspect of the present invention, A method for manufacturing a shape material, in which a plurality of raw materials are successively rolled by a rolling mill to continuously manufacture shape materials, a measuring step of measuring the amount of bending of the shaped material manufactured using the rolling mill and a pair of rolling guides arranged on the outlet side of the rolling mill and guiding the shaped material rolled by the rolling mill in the left-right direction, using a bending measuring device arranged downstream of the pair of rolling guides; a bending amount calculation step of calculating bending amounts in a first region, which is a region from a leading end, which is an end on the downstream side in the conveying direction of the shaped member, to a first distance, and in a second region, which is a region from a trailing end side of the first region to a second distance; a change amount calculation step of calculating a change amount for at least one of a rolling condition, which is a roll gap of the rolling mill, and a guide condition, which is an advance / retreat position of the rolling guide, according to the bent shape of the first region and the bent shape of the second region; a rolling step of performing rolling under the rolling conditions and the guide conditions adjusted by the calculated change amount after the change amount calculation step; A method for manufacturing a profile is provided, comprising:

[0014] (2) In the configuration of (1) above, in the change amount calculation process, the amount of curvature and the direction of curvature of the first region are used as the curvature shape of the first region, and the amount of curvature and the direction of curvature of the second region are used as the curvature shape of the second region.

[0015] (3) According to one aspect of the present invention, A rolling facility for rolling a plurality of materials in sequence to continuously produce shapes, a rolling mill for rolling the material; a pair of rolling guides arranged on an outlet side of the rolling mill and guiding the shape rolled by the rolling mill in the left-right direction; a bending measuring device that is disposed downstream of the pair of rolling guides and measures the amount of bending of the section; a calculation device that calculates a change amount for at least one of a rolling condition that is a roll gap of the rolling mill and a guide condition that is an advance / retract position of the rolling guide according to the measurement result of the bend measuring device; Equipped with The computing device determining whether the amount of bending is within an allowable range; If the amount of bending is not within the allowable range, the amount of bending is calculated in a first region, which is a region from a leading end, which is an end on the downstream side of the conveying direction of the section, to a first distance, and in a second region, which is a region from a trailing end of the first region to a second distance, calculating a change amount of at least one of a rolling condition that is a roll gap of the rolling mill and a guide condition that is an advance / retreat position of the rolling guide according to the bend shape of the first region and the bend shape of the second region; The rolling equipment for a shaped material is provided, in which, when the amount of bending is within an allowable range, the rolling mill and the pair of rolling guides roll under the same rolling conditions and guide conditions as those for the shaped material for which the amount of bending was measured, and, when the amount of change is calculated, roll under the rolling conditions and guide conditions adjusted by the calculated amount of change. [Effects of the Invention]

[0016] According to one aspect of the present invention, there are provided rolling equipment and a rolling method for a section that can appropriately suppress bending depending on the type of bending. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a plan view showing a finishing rolling facility which is a rolling facility according to an embodiment of the present invention. [Figure 2] FIG. 1 is an explanatory diagram showing a rolling line in one embodiment of the present invention. [Figure 3] FIG. 2 is a front view showing a finishing universal rolling mill. [Figure 4] FIG. 2 is a plan view showing the arrangement of a finishing universal rolling mill and rolling guides in the finishing rolling facility. [Figure 5] FIG. 3 is a flowchart showing a method for adjusting rolling conditions and guide conditions in one embodiment of the present invention. [Figure 6] FIG. 1 is a schematic diagram showing the amount of bending of an H-shaped steel. [Figure 7] FIG. 2 is an explanatory diagram showing a first region and a second region in an H-shaped steel. [Figure 8] 1A and 1B are explanatory diagrams showing the bending shapes of H-shaped steel beams, where (A) shows a uniform bend, (B) shows an S-shaped bend, (C) shows a tip bend, and (D) shows a partial bend. [Figure 9] 1A and 1B are explanatory diagrams showing how to calculate the amount of bending of H-shaped steel, where (A) shows the case of uniform bending, (B) shows the case of S-shaped bending, and (D) shows the case of partial bending. [Figure 10] FIG. 10 is a plan view showing a finishing universal rolling mill in a comparative example. [Figure 11] FIG. 2 is a plan view illustrating the positional relationship between the bending direction of the H-shaped steel and the rolling guide. DETAILED DESCRIPTION OF THE INVENTION

[0018] In the following detailed description, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, identical or similar parts are designated by identical or similar reference numerals, and redundant explanations will be omitted. The drawings are schematic and may differ from the actual product. Furthermore, the embodiments shown below exemplify devices and methods for embodying the technical concept of the present invention, and the technical concept of the present invention does not specify the materials, structure, arrangement, etc. of component parts as described below. The technical concept of the present invention can be modified in various ways within the technical scope defined by the claims.

[0019] <Rolling equipment> The configuration of rolling equipment according to one embodiment of the present invention will be described. In this embodiment, the rolling equipment is a finishing rolling equipment 5 installed in a rolling line 1 that produces H-beam steel, a type of shaped material, by rolling materials such as slabs, blooms, and beam blanks. As shown in FIG. 2 , the rolling line 1 includes a heating furnace 2, a roughing rolling equipment 3, an intermediate rolling equipment 4, and a finishing rolling equipment 5. The heating furnace 2 is a device for heating the material to a predetermined temperature. The roughing rolling equipment 3 has a roughing mill that rolls the material. In the roughing rolling equipment 3, the material heated in the heating furnace 2 is rolled (also referred to as "rough rolling") by the roughing mill to produce a rough steel billet, which is a rolled material having a web and flanges on both ends and is approximately H-shaped.

[0020] The intermediate rolling facility 4 includes an intermediate universal rolling mill 41 and an edging rolling mill 42 that roll the rough steel billets produced in the rough rolling facility 3. In the intermediate rolling facility 4, the intermediate universal rolling mill 41 and the edging rolling mill 42, which are used in pairs with the intermediate universal rolling mill 41, perform multiple passes of reverse rolling (also referred to as "intermediate rolling") to roll the rough steel billets, and the rolled material is brought into a shape closer to the product dimensions.

[0021] The finish rolling equipment 5 rolls (also referred to as "finish rolling") the material to be rolled that has been subjected to intermediate rolling, thereby producing H-section steel of the product dimensions. As shown in FIG. 1, the finish rolling equipment 5 comprises a finish universal rolling mill 51, a pair of rolling guides 52, a bending measuring device 53, and a computing device 54. Note that, hereinafter, the direction in which the material to be rolled is transported in finish rolling (the left-right direction in FIG. 1) is referred to as the transport direction (also referred to as the "rolling direction").

[0022] As shown in FIG. 3 , the finishing universal rolling mill 51 has a pair of horizontal rolls 511 and a pair of vertical rolls 512. The pair of horizontal rolls 511 are arranged side by side in the vertical direction with their rotation axes parallel to the left-right direction, sandwiching the material to be rolled between them. The pair of vertical rolls 512 are arranged side by side in the horizontal direction with their rotation axes parallel to the up-down direction, sandwiching the material to be rolled between them. The up-down direction refers to the vertical direction, i.e., the up-down direction in FIG. 3 . The left-right direction refers to the direction perpendicular to the up-down direction and the conveyance direction of the material to be rolled, i.e., the left-right direction in FIG. 3 . As shown in FIG. 1 , the finishing universal rolling mill 51 adjusts the left-right position of the pair of vertical rolls 512 in response to a correction command from a computing device 54. This adjusts the reduction amount of the left and right flanges of the material to be rolled. The reference position of the pair of vertical rolls 512 in the horizontal direction is referred to as the reference position. The reference position is a reference position set so that the H-beam has the product dimensions under normal rolling conditions. In the example shown in Figure 4, the reference positions are the positions where the positions of the inner surfaces in the left and right directions, which are the positions facing each other on the circumferential surfaces of the pair of vertical rolls 512, overlap with the reference line shown by the dotted line extending in the conveying direction.

[0023] A pair of rolling guides (also called "parallel guides" due to their shape) 52 are arranged on the exit side of the finishing universal rolling mill 51 and guide the H-shaped steel 6 rolled by the finishing universal rolling mill 51 in the left-right direction, each having a guide plate of a predetermined length in the rolling direction. Rollers are provided on both ends of the guide plates of the pair of rolling guides 52, upstream and downstream in the conveying direction. These rollers restrain the H-shaped steel from bending in the left-right direction by abutting the peripheral surfaces of the rotatable rollers against the outer surfaces of the left and right flanges of the H-shaped steel. A tapered section, commonly called a "lead-in," is provided at the tip of the rolling guide 52 on the side closest to the finishing universal rolling mill 51.

[0024] The pair of rolling guides 52 are spaced apart in the left-right direction, sandwiching the H-beam emerging from the finishing universal rolling mill 51. The pair of rolling guides 52 are configured to be movable in the left-right direction in response to commands from a computing device 54. Here, the reference position of the pair of rolling guides 52 in the left-right direction is referred to as the reference position. The reference position of the pair of rolling guides 52 corresponds to the pair of vertical rolls 512, and is the position where the positions of the rolling core-side circumferential surfaces of the rolls provided in the pair of rolling guides 52 are the same as the inner positions of the circumferential surfaces of the pair of vertical rolls 512, which are the reference positions. In the example shown in FIG. 4 , the reference positions are the positions where the positions of the rolling core-side circumferential surfaces of the rollers of the pair of rolling guides 52 overlap with the reference line, indicated by the dotted line, extending in the conveyance direction. The amount of deviation of the pair of rolling guides 52 from the reference position is referred to as the adjustment amount S. The adjustment amount S is 0 mm when the rolling guide 52 is in the reference position, a negative deviation amount (mm) when the rolling guide 52 is closer to the rolling core than the reference position, and a positive deviation amount (mm) when the rolling guide 52 is on the opposite side of the reference position toward the rolling core. In the example shown in FIG. 4, the rolling guide 52 on the left side in the left-right direction (upper side in FIG. 4) is in the reference position, and the rolling guide 52 on the right side in the left-right direction (lower side in FIG. 4) is in a state where it is deviated to the positive side. Note that, hereinafter, the left-right positions of the pair of rolling guides 52 are also referred to as the advance / retract positions. In addition, in this embodiment, "increasing the advance / retract position (of the rolling guide 52)" means moving the rolling guide 52 away from the rolling core, and the value of the adjustment amount S increases in the positive direction. On the other hand, "decreasing the advance / retract position (of the rolling guide 52)" means moving the rolling guide 52 closer to the rolling core.

[0025] As shown in Figure 4, the distance parallel to the conveying direction from the vertical roll 512 of the finishing universal rolling mill 51 to the roller furthest upstream in the conveying direction of the pair of parallel guides 52 (the distance at the axial center position of each roller) is referred to as the installation distance L.

[0026] The bending measuring device 53 is a device for measuring the bending shape of the finish-rolled H-beam, which is the rolled material coming out of the finishing universal rolling mill 51. It is located downstream in the conveying direction from the pair of rolling guides 52. The bending shape refers to the shape of the bending at a position on the outer surface of one of the left and right flanges when the H-beam is viewed in a plan view parallel to the flanges. It is also a bending profile of the H-beam, which indicates the lateral deviation of each position from a reference position for multiple positions along the length of the flange outer surface. The bending profile uses data indicating the lateral positions of one of the flange outer surfaces at the multiple longitudinal positions. Specifically, the distance from a predetermined reference lateral position (e.g., the position of the bending measuring device 53) to the above-mentioned lateral position may be used. Alternatively, the rolling tip position of the H-beam (the position of the longitudinal tip that is rolled first) and a position a predetermined length from the rolling tip position in the longitudinal direction may be defined as the two ends of the bending profile, and the left-right position of a line connecting the left-right positions at these two ends may be defined as 0, and the left-right distances (positive or negative values) from this position to the above-mentioned multiple longitudinal positions may be used. The bending measurement device 53 is not particularly limited as long as it can measure the bending shape of the H-beam. In this embodiment, as an example, the bending measurement device 53 has three or more laser distance meters installed downstream of the pair of rolling guides 52 in the conveying direction and outside the left-right direction of the H-beam being conveyed. These laser distance meters are installed in a row at a predetermined pitch in the conveying direction and continuously measure the left-right distance from the H-beam being conveyed at predetermined time intervals. The bending measuring device 53 then calculates the amount of bending at each measurement time from the difference in distances measured by the three or more laser distance meters, and by superimposing these in time series, calculates the bending shape of the H-beam in the longitudinal direction. The bending measuring device 53 transmits the measurement results of the amount of bending of the H-beam to the calculation device 54.

[0027] The computing device 54 is electrically connected to the finishing universal rolling mill 51, the pair of rolling guides 52, and the bending measuring device 53. The computing device 54 adjusts the rolling conditions and guide conditions of the H-beam by controlling the finishing universal rolling mill 51 and the pair of rolling guides 52 according to the measurement results of the bending shape of the H-beam measured by the bending measuring device 53. Here, the rolling conditions are conditions that contribute to the occurrence of bending during finish rolling by the finishing universal rolling mill 51, and in this embodiment, refer to the positions of the pair of vertical rolls 512 during rolling. In other words, the rolling conditions correspond to the gaps (roll gaps) between each vertical roll 512 and the pair of horizontal rolls 511. Furthermore, the guide conditions are conditions for guiding the H-beam being transported by the pair of rolling guides 52, and are the forward / backward positions of the pair of rolling guides 52 (i.e., the adjustment amount S). Details of how the computing device 54 adjusts the rolling conditions and guide conditions will be described later. The arithmetic device 54 may be a control panel composed of a plurality of devices such as arithmetic devices and control devices for realizing the functions of calculation and control in the method for adjusting rolling conditions, which will be described later. The arithmetic device 54 may also be a computer system having an arithmetic processing function for realizing each of these functions by executing a program on computer software. This computer system is composed of a ROM, a RAM, a CPU, etc., and realizes each of the above-mentioned functions on software by executing various dedicated programs stored in advance in the ROM, etc.

[0028] <Rolling method for shapes> Next, a method for rolling shaped steel according to this embodiment will be described. In this embodiment, in a rolling line 1, a plurality of materials heated in a heating furnace 2 are subjected to rough rolling, intermediate rolling, and finish rolling in that order to continuously manufacture H-shaped steel. In this process, as will be described later, in the finish rolling, the rolling conditions and guide conditions are changed depending on the bending shape of the H-shaped steel that has been previously rolled. Furthermore, continuous rolling is basically the continuous rolling (continuous rolling) of H-shaped steel 6 made of the same material and with the same cross section, and the rolling of a plurality of H-shaped steel 6 by continuous rolling is also referred to as a continuous rolling process.

[0029] In this embodiment, the first material is first subjected to rough rolling, intermediate rolling, and finish rolling in the roughing rolling facility 3, intermediate rolling facility 4, and finish rolling facility 5 to produce an H-beam. Then, according to the process flow shown in FIG. 5 , the rolling results of the first material are used to determine the amount of change in at least one of the rolling conditions and guide conditions for the finish rolling of the second and subsequent materials, and at least one of the rolling conditions and guide conditions is adjusted. Furthermore, in a continuous rolling opportunity, the rolling conditions and guide conditions are adjusted based on the rolling results of the previous H-beam 6 rolled in the same continuous rolling opportunity. For example, in the same continuous rolling opportunity, the rolling conditions and guide conditions may be adjusted until the bending is eliminated, depending on the rolling results of the previous rolling. The rolling conditions and guide conditions for the rolling of the first material are not particularly limited, and standard conditions commonly used in the process may be used.

[0030] In adjusting the rolling conditions and guide conditions, as shown in Fig. 5, first, the bending shape of the H-beam that has been finish-rolled in the finish rolling facility 5 is measured by a bending measuring device 53 (S100, measurement step). In step S100, the bending shape of the H-beam is measured by continuously measuring the distance from the bending measuring device 53 to the H-beam using a laser distance meter in the bending measuring device 53 over the entire length of the H-beam for a predetermined length in the longitudinal direction from the tip end of the H-beam. This predetermined length in the longitudinal direction is usually up to about 10 m, and it is sufficient to measure the sum (X+Y) of the longitudinal lengths of regions R1 and R2 in Fig. 7, which will be described later.

[0031] Next, the calculation device 54 calculates the first bending amount δ1 and the second bending amount δ2 in the first region R1 and the second region R2 (S102, bending amount calculation step). As shown in FIG. 7, the first region R1 and the second region R2 are regions at the end of the H-shaped steel 6 on the leading end side in the longitudinal direction (downstream side in the conveying direction). The first region R1 is a region extending from the leading end 61, which is the end of the H-shaped steel 6 on the downstream side in the conveying direction, to a position a first distance X toward the trailing end. The second region R2 is a region extending from the end of the trailing end of the first region R1 to a position a second distance Y in the longitudinal direction. Details of the first distance X and the second distance Y will be described later.

[0032] The first bending amount δ1 is the bending amount of the H-shaped steel 6 in the first region R1. It is the distance between a chord drawn with respect to the bending profile and the bending profile at the longitudinal position where the distance between this chord and the bending profile is the longest. The bending profile is the shape of the bending when the H-shaped steel 6 is viewed in plan as shown in FIG. 7 . In this embodiment, it is indicated by the position of one flange outer surface (side surface) of the H-shaped steel 6. The first bending amount δ1 is expressed with a positive or negative sign depending on the bending direction. In this embodiment, as an example, a bending to the right as viewed from the rolling tip is positive (plus), and a bending to the left as viewed from the rolling tip is negative (minus). The second bending amount δ2 is the bending amount of the H-shaped steel 6 in the second region R2 and is calculated in the same way as the first bending amount δ1. The second bending amount δ2 is also expressed with a positive or negative sign depending on the bending direction, as with the first bending amount δ1. It is preferable to convert the first bending amount δ1 and the second bending amount δ2 into bending amounts per unit length. For example, the first bending amount δ1 and the second bending amount δ2 may be expressed as bending amounts (mm) per meter of length. In this case, if the bending is within 1 mm per meter of length, it can be determined that the bending is good, with a 0 mm change amount, whereas if the bending is greater than 1 mm, it can be determined that bending adjustment is necessary. Regarding the bending direction, in this embodiment, as shown in FIG. 11 , when the H-shaped steel 6 is bent so as to be convex upward in a view of the steel, the side of the upper rolling guide 52B is also referred to as the "convex side," and the side of the lower rolling guide 52A is also referred to as the "concave side."

[0033] (Various bending modes of H-shaped steel) Here, Fig. 8 shows examples of the bending shapes of H-shaped steel products, such as H-shaped steel, that have been finish-rolled in a finishing rolling facility 5 and cut to a predetermined product length. The bending shapes shown in Fig. 8 include uniform bending (Fig. 8(A)), S-shaped bending (Fig. 8(B)), tip bending (Fig. 8(C)), and partial bending (Fig. 8(D)). Note that Fig. 8 shows the bending shape of an H-shaped steel product taken from the tip end of an H-shaped steel 6 that has been rolled from a single piece of material to form multiple products. The uniform bending shown in Fig. 8(A) is a type of bending in which the steel bends almost uniformly in one direction. The S-shaped bending shown in Fig. 8(B) is a type of bending in which the direction of bending changes midway in the longitudinal direction. The end bending shown in Fig. 8(C) is a type of bending in which the curvature is large at the tip end and decreases toward the rear end. The partial bend shown in Figure 8(D) is a type of bend where there is a bend in a part of the longitudinal direction (not the tip). There are also types of bends where the left-right bend is reversed to that shown in Figure 8. Products with such complex bend shapes are overwhelmingly found in products taken from the longitudinal position that becomes the tip during finish rolling, and the majority of products that require press straightening due to bends are also products taken from the tip of finish rolling. In particular, S-shaped bends, end bends, and partial bends shown in Figures 8(B), (C), and (D) are difficult to press straighten, so it is important to suppress these types of bends.

[0034] FIG. 9 also shows an example of a method for calculating the bending amount δ, illustrating a method for calculating the first bending amount δ1 and the second bending amount δ2 for an H-shaped steel 6 that has uniform bending, S-shaped bending, and partial bending. FIG. 9(A) shows a bending profile for uniform bending. In FIG. 9(A), the signs of the first bending amount δ1 and the second bending amount δ2 are positive and the same, and the bending amounts (absolute values) per unit length are approximately the same. FIG. 9(B) shows a bending profile for S-shaped bending. In FIG. 9(B), the sign of the first bending amount δ1 is positive and the sign of the second bending amount δ2 is negative, meaning the signs are reversed. FIG. 9(C) shows a bending profile for end bending. In the case of FIG. 9(C), the first bending amount δ1 and the second bending amount δ2 have the same positive sign, and the bending amount (absolute value) per unit length of the second bending amount δ2 is greater than that of the first bending amount δ1.

[0035] The inventors performed rolling on the rolling line 1 having the equipment arrangement shown in Figures 1 and 2, changing the rolling conditions of the finishing universal rolling mill 51 and the advance / retract position of the rolling guide 52. Then, while checking the contact state of the H-section steel 6 with the rolling guide 52, they investigated the bending shape of the H-section steel 6 after finish rolling for a length of 10 m from the rolling tip using a bending measuring device 53.

[0036] The advance / retract position of the rolling guide 52 is a value indicating how far the rolling core side circumferential surface of the roller incorporated in the rolling guide 52 advances / retracts relative to a reference line shown by a dashed line, as shown in Fig. 4. The reference line shown in Fig. 4 is a line extending in the rolling direction from the circumferential surface of the rolling core side (inner side) of the vertical roll 512 of the finishing universal rolling mill 51. The direction in which the rolling guide 52 moves away from the H-shaped steel 6 being rolled is indicated by a sign + (plus), and the direction in which the rolling guide 52 moves closer to the H-shaped steel 6 is indicated by a sign - (minus).

[0037] Furthermore, the longitudinal distance from the center of the finishing universal rolling mill 51 to the center of the roller closest to the finishing universal rolling mill 51 incorporated in the rolling guide 52 is defined as the installation distance L of the rolling guide 52. Note that in the case of a parallel guide type rolling guide 52, if no rollers are incorporated within the rolling guide 52, the installation distance L may also be the distance to the position where the call-in section of the rolling guide 52 ends. Also, even if the pickup amount between the roller surface of the rolling guide 52 and the guide plate surface (the amount that indicates how much the roller protrudes from the plate surface) is very small, the installation distance L may also be the distance to the position where the call-in section of the rolling guide 52 ends.

[0038] As a result of the investigation, it was found that, apart from the size of the bend, the shape of the bend can be roughly divided into the forms shown in Figure 9(A), (B), and (C), and that sometimes the curvature of the bend can become large at a certain distance from the rolling tip, as shown in Figure 9(D). After a detailed observation of the guiding conditions during the rolling of H-section steel 6 in which these bend forms occurred, the following bend occurrence conditions were found.

[0039] The occurrence of S-shaped bending is as follows: If the rolling conditions for the H-shaped steel 6 are inappropriate, a large bend will occur in the H-shaped steel 6. Then, when the leading end of the H-shaped steel 6 hits the rolling guide 52, the direction of the bend changes in the longitudinal section that is being rolled by the finishing universal rolling mill 51, resulting in an S-shaped bend.

[0040] The circumstances under which partial bending occurs are as follows: When partial bending occurs, the rolling conditions for the H-shaped steel 6 are appropriate, and the leading edge of the steel is rolled straight. However, because the advance / retraction position of the rolling guide 52 is incorrect in the negative direction (approaching the H-shaped steel 6), when the leading edge of the H-shaped steel 6 hits the rolling guide 52, bending occurs in the longitudinal section being rolled by the finishing universal rolling mill 51.

[0041] Based on these findings, the rolling conditions and the adequacy of the guide advance / retreat positions for the various bending forms shown in Figure 8 can be summarized as follows: (uniform curve) Rolling conditions: The rolling conditions are such that bending occurs. Guide advance / retract position: The guide advance / retract position is too wide in the + (plus) direction. (S-shaped bend) Rolling conditions: The rolling conditions are such that bending occurs. Guide advance / retract position: It may be on the negative (-) side of the correct position. (edge ​​bending) Rolling conditions: The rolling conditions are such that bending occurs. Guide advance / retract position: The guide advance / retract position is appropriate. (Partially bent) Rolling conditions: The rolling conditions are appropriate. Guide advance / retract position: It is on the negative (-) side of the correct position.

[0042] In order to classify and correct such bending patterns, in this embodiment, a first distance X from the rolling tip is defined, which is the distance at which the rolling guide affects the bending shape of the H-shaped steel 6. The first distance X is the length from the portion of the H-shaped steel 6 that is being rolled when the longitudinal tip of the H-shaped steel 6 contacts the rolling guide 52 to the tip of the H-shaped steel 6. The first distance X can be determined taking into account the shape of the tip crop of the H-shaped steel 6 and the contact state with the guide, but ultimately can be set to a value approximately equal to the installation distance L of the rolling guide 52 described above. A specific example of the first distance X is often a value of approximately 2 to 3 m, depending on the guide shape at the rear of the rolling mill. The second distance Y is not particularly limited, but may be the same as or approximately the same as the first distance X, or may be one to three times the first distance X.

[0043] After step S102, the calculation device 54 calculates the amount of change in at least one of the rolling conditions of the finishing universal rolling mill 51 and the advance / retract position of the rolling guide 52, according to the first bending amount δ1 and the second bending amount δ2 that have been found (S104, change amount calculation step). In step S104, a rolling condition determination step for determining the amount of change in the rolling conditions of the finishing universal rolling mill 51 and an advance / retract position determination step for determining the amount of change in the advance / retract position of the rolling guide 52 are performed, thereby determining each amount of change.

[0044] (Rolling condition determination process) In the rolling condition determination step, if the first bend amount δ1 falls within a first permissible range, it may be determined that no change in the rolling conditions is necessary. Alternatively, if the calculated change amount is a very small amount, for example, within ±0.05 mm, it may also be determined that no change in the rolling conditions is necessary. The first permissible range is a value set based on quality tolerances. Furthermore, since bends in the first region R1 are largely uniform bends, S-shaped bends, and end bends, the first permissible range may be set so that partial bends and other bends can be distinguished in the first region R1. If it is determined that no change in the rolling conditions is necessary, the change amount in the rolling conditions is set to zero. On the other hand, if the rolling conditions are to be changed, the change amount in the rolling conditions is determined by the following method.

[0045] In changing the rolling conditions, the amount of change is determined so that the positions of the pair of vertical rolls 512 are relatively shifted in the left-right direction depending on the direction of the curve in the first region R1, i.e., the sign of the first curve amount δ1. At this time, for the vertical roll 512 on the concave side of the curve in the first region R1, the amount of change is determined so that the vertical roll 512 moves by a predetermined movement amount ΔV in a direction that reduces the gap between the vertical roll 512 and the horizontal roll 511. On the other hand, for the vertical roll 512 on the convex side of the curve in the first region R1, the amount of change is determined so that the vertical roll 512 moves by the predetermined movement amount ΔV in a direction that increases the gap between the vertical roll 512 and the horizontal roll 511.

[0046] The movement amount ΔV may be determined, for example, according to the first bending amount δ1, as shown in equation (1). ΔV=K v δ1 (1) where K v is a coefficient, and it is sufficient to investigate in advance the amount of change in bending when the rolling conditions are changed, and determine it for each cross section (shape and size) of the H-beam 6 and steel type based on that data.

[0047] (advance / retreat position determination process) In the advance / retract position determination process, if the second bend amount δ2 falls within a second allowable range, it may be determined that no change in the advance / retract position is necessary. Alternatively, if the calculated change amount is a small amount, for example, within ±0.2 mm, it may be determined that no change in the advance / retract position is necessary. Similar to the first allowable range, the second allowable range is a value set based on quality tolerances. Furthermore, since bends in the second region R2 are largely uniform bends, S-shaped bends, and partial bends, the second allowable range may be set so that end bends and other bends can be distinguished in the second region R2. If it is determined that no change in the advance / retract position is necessary, the change amount in the advance / retract position is set to zero. On the other hand, if a change in the advance / retract position is to be made, the change amount in the advance / retract position is determined using the following method.

[0048] The amount of change in the advance / retreat position is determined according to the first bending amount δ1, the second bending amount δ2, and the signs of the first bending amount δ1 and the second bending amount δ2, and is classified into the following three conditions (a) to (c). (a) When the signs of the first bending amount δ1 and the second bending amount δ2 are the same and the second bending amount δ2 is outside the second allowable range (in the case of uniform bending) In this case, the advance / retract position of the rolling guide 52 on the concave side of the curve of the second region R2 is changed in a direction to reduce the advance / retract position. a may be determined according to the magnitude of the second bending amount δ2, for example, as shown in equation (2). ΔS a =K a δ2 (2)

[0049] (b) When the signs of the first bending amount δ1 and the second bending amount δ2 are opposite and the second bending amount δ2 is outside the second allowable range (in the case of an S-shaped bending) In this case, the advance / retract position of the rolling guide 52 on the convex side of the curve of the second region R2 is changed in a direction to increase the advance / retract position. b may be determined according to the magnitude of the second bending amount δ2, for example, as shown in equation (3). ΔS b =K b δ2 (3)

[0050] (c) When the first bending amount δ1 is within the first tolerance range and the second bending amount δ2 is outside the second tolerance range (in the case of partial bending) In this case, the advance / retract position of the rolling guide 52 on the convex side of the curve of the second region R2 is changed in a direction to increase the advance / retract position. c may be determined according to the magnitude of the second bending amount δ2, for example, as shown in equation (4). ΔS c =K c |δ2| (4) In addition, K a ~K cis a coefficient, and it can be determined based on the cross section (shape and size) and steel type of the H-beam 6 by investigating the change in bending when the forward / backward position is changed in advance.

[0051] Furthermore, the amount of change in the advance / retract position of the rolling guide 52 does not necessarily have to follow equations (2) to (4). For example, the amount of change per rolling material may be determined in advance to a predetermined value (e.g., 1 mm), and the advance / retract position of the rolling guide 52 may be changed for each material based on the bending shape. Furthermore, the rolling guides 52 are arranged in a pair in the left-right direction, but the position of the rolling guide 52 other than the rolling guide 52 that was described above as being moved may be left unchanged. Furthermore, this other rolling guide 52 may be adjusted in the opposite direction to the amount of change in the advance / retract position of the rolling guide 52 that was described above as being moved (in other words, adjustment may be made by moving the pair of rolling guides 52 in parallel).

[0052] That is, in step S104, the amount of change in the rolling conditions of the finish universal rolling mill 51 is determined according to the bending shape in the first region R1. Also, in step S104, the amount of change in the guide conditions is determined according to the bending shape in the first region R1 and the bending shape in the second region R2. Note that the bending shape refers to the amount of bending δ (or the absolute value of the amount of bending δ) and the direction of bending (positive or negative of the amount of bending δ) in each region. After step S104, the calculation device 54 adjusts the roll gap of the finishing universal rolling mill 51 and the advance / retract position of the rolling guide 52 so that the amounts of change are the amounts obtained in step S104 (S106).

[0053] The method for manufacturing a profile according to this embodiment is as follows: A method for manufacturing a shape material in which a plurality of materials are successively rolled by a rolling mill (finishing universal rolling mill 51) to continuously manufacture H-shaped steel 6, A measurement step (S100) of measuring the amount of bending of the H-shaped steel 6 manufactured using a rolling mill and a pair of rolling guides 52 arranged on the delivery side of the rolling mill and guiding the H-shaped steel 6 rolled by the rolling mill in the left-right direction, using a bending measuring device 53 arranged downstream of the pair of rolling guides 52; a bending amount calculation step (S102) for calculating the bending amount in a first region R1, which is a region from the leading end, which is the end downstream in the conveying direction of the H-shaped steel 6, to a first distance X, and in a second region R2, which is a region from the tail end of the first region R1 to a second distance Y; a change amount calculation step (S104) of determining a change amount of the rolling condition, which is the roll gap of the rolling mill, according to the bending shape of the first region R1, and determining a change amount of the guide condition, which is the advance / retreat position of the rolling guide 52, according to the bending shapes of the first region R1 and the second region R2; After the change amount calculation step, a rolling step is performed under the rolling conditions and guide conditions adjusted by the determined change amount; Equipped with.

[0054] In addition, in the method for manufacturing a profile according to this embodiment, in the change amount calculation process, the bending amount and bending direction of the first region R1 may be used as the bending shape of the first region R1, and the bending amount and bending direction of the second region R2 may be used as the bending shape of the second region R2.

[0055] The rolling equipment for the shaped material (finishing rolling equipment 5) according to this embodiment is: A rolling mill for rolling a plurality of materials sequentially to continuously manufacture H-shaped steel 6, a rolling mill (finishing universal rolling mill 51) for rolling the material; A pair of rolling guides 52 are arranged on the delivery side of the rolling mill and guide the H-shaped steel 6 rolled by the rolling mill in the left and right directions; a bending measuring device 53 that is arranged downstream of the pair of rolling guides 52 and measures the bending amount of the H-shaped steel 6; a computing device 54 that adjusts at least one of the rolling conditions, which are the roll gap of the first rolling machine, and the guide conditions, which are the advance / retract positions of the rolling guides 52, according to the measurement results of the bending measuring device 53; Equipped with The calculation device 54 If the amount of bending is not within the allowable range, the amounts of bending in a first region R1, which is a region from the leading end, which is the end on the downstream side of the H-shaped steel 6 in the conveying direction, to a first distance X, and in a second region R2, which is a region from the tail end of the first region R1 to a second distance Y, are calculated. calculating a change amount of the rolling condition, which is the roll gap of the rolling mill, and a change amount of the guide condition, which is the advance / retreat position of the rolling guide 52, according to the bend shape of the first region and the bend shape of the second region; The rolling mill and the pair of rolling guides 52 perform rolling under the rolling conditions and guide conditions adjusted by the calculated change amount.

[0056] According to this configuration, by changing the rolling conditions and guide conditions depending on the bending shape of the first region R1 and the second region R2, bending can be appropriately suppressed for various bending forms such as uniform bending, S-shaped bending, tip bending, and partial bending.

[0057] When calculating the amount of change, a method can be used in which the amount of change in the rolling conditions is calculated according to the bending shape of the first region R1, and the amount of change in the guide conditions is determined according to the bending shape of the first region R1 and the bending shape of the second region R2. By changing the rolling conditions and guide conditions according to this method, bending can be more accurately suppressed for various bending forms such as uniform bending, S-shaped bending, tip bending, and partial bending.

[0058] <Modification> Although the present invention has been described above with reference to specific embodiments, it is not intended that the invention be limited by these descriptions. By referring to the description of the present invention, other embodiments of the present invention that include various modifications in addition to the disclosed embodiments will be apparent to those skilled in the art. Therefore, it should be understood that the embodiments of the invention set forth in the claims also encompass embodiments that include these modifications described herein, either alone or in combination.

[0059] For example, before step S102, the total length bending amount δ is calculated from the measurement result of step S100.A The total length bending amount δ A A step of determining whether the total length bending amount δ is within an allowable range may be performed. A is the amount of bending in the entire length of the H-shaped steel 6. And the total length bending amount δ A If the amount of bending of the entire length δ is not within the allowable range, the processing from step S102 onwards is carried out. A If the difference is within the allowable range, the rolling conditions and guide conditions are not adjusted.

[0060] Furthermore, although the above embodiment has been described using an H-beam 6 as an example of a shaped material, the present invention can also be applied to other shaped materials. For example, when finish rolling of channel steel or I-beam steel is performed using universal rolling, the rolling conditions can be changed by correcting the position of the vertical roll in the finish universal rolling, as in the case of H-beam steel. Furthermore, when finish rolling is performed using a pair of upper and lower rolls (without a vertical roll), such as steel sheet piles or angle steel, the rolling conditions can be changed using the following method. That is, by tilting the axis of one of the upper and lower rolls from the horizontal direction to tilt it relative to the other roll, a so-called "leveling" can be performed to change the state of bending. Therefore, the rolling conditions can be changed by "leveling." Furthermore, the material of the shaped material does not have to be steel; it can be other materials, such as copper or aluminum, as long as it can be formed into a shape by rolling. [Example]

[0061] An example carried out by the present inventors will be described. In the example, rolling of H-beams 6 with cross-sectional dimensions of H900 mm x 300 mm x 16 mm x 28 mm was carried out in the rolling line 1 for H-beams 6 shown in Figures 1 and 2 was carried out. The first rolled piece was rolled under standard rolling conditions. Thereafter, for the second to tenth rolled pieces, the rolling conditions and guide conditions were sequentially modified for the finish rolling in accordance with the actual bending results of the previously rolled shaped pieces, as in the above embodiment (invention example).

[0062] For comparison, as disclosed in Patent Document 1, the amount of bow was measured using a bow measuring device, and rolling was also performed in which only the gap between the vertical roll 512 and the horizontal roll 511 was adjusted for the second to tenth rolls based on the amount of bow (Comparative Example 1). As another comparison, as in Patent Document 3, nine raw materials were rolled using a finish rolling facility 5a in which a pair of constraint rollers 55 was installed 1.7 m downstream from the rolling core between a finish universal rolling mill 51 and a rolling guide 52, as shown in FIG. 10 (Comparative Example 2). In Comparative Example 2, rolling was performed by adjusting the advance / retract positions of the pair of constraint rollers 55 so that the peripheral surface positions of the constraint rollers 55 and the vertical roll 512 of the finish universal rolling mill 51 on the rolling core side were aligned. In Comparative Example 2, the advance / retract position of the rolling guide 52 was kept constant at 20 mm.

[0063] In the invention example and comparative examples 1 and 2, the first distance X was set to 2.5 m, and the second distance Y was set to 2.5 m. In addition, for the adjustment for each material, in the invention example and comparative example 1, the coefficient K v =0.2 and the vertical roll gap was adjusted.

[0064] In the example of the invention, the amount of change in the rolling guide 52 is determined according to the formulas (2) to (4), and the coefficients of each formula are K a =-2.0,K b =-1.0,K c = 2.0, and the advance / retract position of the rolling guide 52 was adjusted. In the example of the invention, the rolling guide 52 on the other side was moved parallel to the rolling guide 52 on one side. Here, the rolling guide 52 on one side is the rolling guide 52 whose advance / retract position is adjusted in step S108, and the rolling guide 52 on the other side is the rolling guide 52 on the opposite side to the rolling guide 52 on one side.

[0065] For these examples, nine products each with a length of 10 m were collected from the rolling tip and the occurrence of bending was investigated. In the investigation, the first bending amount δ1 was measured for a length section (first region R1) from the tip of the product to a distance of 2.5 m, and the second bending amount δ2 was measured for a length section (second region R2) from the tip to 2.5 m to 5 m. 2The amount of bending δ2 was measured. The control range for δ1 and δ2 is 2.5 mm per 1 m or less in absolute value.

[0066] In addition, the total length bending amount δ A In this case, when the bending mode is an S-shaped bending, the bending amount δ t and the amount of bending δ b The sum of the absolute values ​​of and is the total length bending amount δ A The total length bending amount δ A The control range is an absolute value of 10 mm or less per 10 m. The results of the examples are summarized in Table 1. The first bending amount δ1 and the second bending amount δ2 are given positive or negative signs according to the bending direction, and the total length bending amount δ A are shown as absolute values. In Table 1, values ​​outside the control range are underlined.

[0067] [Table 1]

[0068] In Comparative Example 1, the full-length bending was unstable, and five products were produced that were outside the target bending tolerance of 10 mm or less. In Comparative Example 2, although the full-length bending was within the control range, S-shaped bending and end bending were likely to occur, and four products were produced in which the first bending amount δ1 and the second bending amount δ2 were outside the target. Furthermore, in Comparative Example 2, partial bending also occurred in one product. In contrast to this, in the example of the present invention, the advance / retreat position of the rolling guide 52 and the finish rolling conditions can be set appropriately based on the curve shape, so there were no products that did not meet the target curve tolerance, which was a good result. Thus, the effects of the present invention are clear. [Explanation of symbols]

[0069] 1. Rolling line 2 Furnace 3 Rough rolling equipment 4. Intermediate rolling equipment 41 Intermediate universal rolling mill 42 Edging Rolling Mill 5,5a Finishing rolling equipment 51 Finishing universal rolling mill 511 Horizontal Roll 512 Vertical Roll 52 Rolling guide 53 Bend measurement device 54 Arithmetic unit 55 Restrained Roller 6 H-shaped steel

Claims

1. A method for manufacturing a shape material, in which a plurality of raw materials are successively rolled by a rolling mill to continuously manufacture shape materials, a measuring step of measuring the amount of bending of the shaped material manufactured using the rolling mill and a pair of rolling guides arranged on the outlet side of the rolling mill and guiding the shaped material rolled by the rolling mill in the left-right direction, using a bending measuring device arranged downstream of the pair of rolling guides; a bending amount calculation step of calculating bending amounts in a first region, which is a region from a leading end, which is an end on the downstream side in the conveying direction of the section, to a first distance, and in a second region, which is a region from a trailing end side of the first region to a second distance; a change amount calculation step of calculating a change amount of at least one of a rolling condition that is a roll gap of the rolling mill and a guide condition that is an advance / retreat position of the rolling guide, according to the bent shape of the first region and the bent shape of the second region; a rolling step of performing rolling under the rolling conditions and the guide conditions adjusted by the determined change amount after the change amount calculation step; Equipped with A method for manufacturing a profile, wherein in the change amount calculation process, the amount of bending and the direction of bending of the first region are used as the bending shape of the first region, and the amount of bending and the direction of bending of the second region are used as the bending shape of the second region.

2. A rolling facility for rolling a plurality of materials in sequence to continuously produce shapes, a rolling mill that rolls the material; a pair of rolling guides arranged on an outlet side of the rolling mill and guiding the shape material rolled by the rolling mill in a left-right direction; a bending measuring device that is disposed downstream of the pair of rolling guides and measures the amount of bending of the shaped member; a calculation device that calculates a change amount for at least one of a rolling condition that is a roll gap of the rolling mill and a guide condition that is an advance / retract position of the rolling guide according to the measurement result of the bend measuring device; Equipped with The computing device A bending amount is calculated in a first region, which is a region from a leading end of the section on the downstream side in the conveying direction to a first distance, and in a second region, which is a region from a trailing end of the first region to a second distance; calculating a change amount for at least one of a rolling condition, which is a roll gap of the rolling mill, and a guide condition, which is an advance / retreat position of the rolling guide, according to the bent shape of the first region and the bent shape of the second region; the amount and direction of bending of the first region are used as the bending shape of the first region, and the amount and direction of bending of the second region are used as the bending shape of the second region; The rolling mill and the pair of rolling guides perform rolling under the rolling conditions and guide conditions adjusted by the calculated change amount.

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