This application is based on Japanese Patent Application No. 2017-102423, filed in Japanese on May 24, 2017, and claims priority, the contents of which are incorporated herein.
[0002]
　The present invention relates to a method of manufacturing the H-shape steel slab like a rectangular cross-section as a material.
BACKGROUND
[0003]
　In the production of H-section steel, and shaped into coarse profile (the rolled material of so-called dog-bone shape) material slab or bloom like extracted from the heating furnace by the rough rolling mill (BD), the intermediate universal rolling machine by then rolling the thickness of the web and the flanges of the crude shaped product, wrought and shaping of the width reduction and the end face flange to the material to be rolled is applied by edger rolling mill close to the intermediate universal rolling mill together . Then, H-shaped steel product by finishing universal rolling machine is shaped.
[0004]
　In the manufacturing method of the H-shaped steel, in shaping the rough profile of the called dogbone shape away from the slab material is a rectangular cross section, put an interrupt to the slab end faces in a first caliber of rough rolling step after spread split the interruption in the second and subsequent grooved, or an interrupt depth is deep, techniques for erasing the interruption of the slab end faces are known in the subsequent caliber.
[0005]
　Further, in the production of H-section steel, material end faces of such slabs (slab end surface) after the so-called edging rolling to edging, rotate the material to be rolled 90 ° or 270 °, a flat shaping of performing reduction of the web corresponding section carrying out the rolling are known. In this flat shaped rolling reduction and shaping of the flange corresponding portion with pressure of the web corresponding section is performed.
　By the way, in recent years, more large of H-shaped steel products has been demanded. Therefore it is possible to manufacture the H-section steel products from large slab materials conventionally been studied. Here, in a general flat shaping rolling, a large material when the material to be rolled, deformation of elongation and flange corresponding portion of the web height direction, there is that various problems, correction of shape there is a case to be determined. Such Specifically, with the pressure of the web corresponding section, the web corresponding section is stretched in the longitudinal direction, a flange corresponding portion is pulled in the drawing is also stretched in the longitudinal direction, the thickness of the flange corresponding portion becomes thinner phenomenon has been a concern.
[0006]
　For such a flat shaped rolling, for example, Patent Document 1, a groove is formed in the central portion of the flat shaped caliber, the non-reduction portion is provided at the center of the web corresponding section during rolling, to reduce the length of the crop portion techniques have been disclosed. The patent document 1 (corresponding to the raised portion of the present invention) protrusion at the center of the web corresponding section are described that perform edging rolling in a state of being formed, a further crop unit reduction and rolling efficiency is achieved.
[0007]
　Further, for example, Patent Document 2, tentering rolling method for advantageously shaping process the crude shaped steel strip is disclosed in the process of manufacturing the shaped steel. Specifically, the Patent Document 2 performs a local rolling to the web corresponding section, then, subjected to rolling for tentering to planarize the protrusion of the central web corresponding section, then, make a material to be rolled rolling method for performing edging rolling is disclosed. Flange width by this method, web thickness, and adjust the web height is to be able to produce a large number of types of crude shaped steel piece.
CITATION
Patent Document
[0008]
Patent Document 1: JP 59-35802 Patent Publication
Patent Document 2: JP 57-146405 JP
Summary of the Invention
Problems that the Invention is to Solve
[0009]
　As described above, in recent years, it has been desired production of large H-shaped steel products due to the size of the structure or the like. Especially products broadened compared contribute significantly flange strength and rigidity of the H-shaped steel conventionally been desired. Flange to produce a H-shaped steel products that are broadening, it is necessary to shape the large material to be rolled flange width compared with conventionally shaped in the rough rolling step.
[0010]
　In the production of H-shaped steel products, conventional, flat shaped rolling time in order to prevent out chew at the flange outer side surface located in, by performing reversed the material to be rolled with a light reduction rolling edging caliber after the flat shaping rolling intellectual It is. The soft reduction rolling can be said to speak auxiliary positioning edging rolling. This is referred to herein as "supplemental edging rolling process (supplementary edging process)" or simply referred to as "ancillary edging rolling (supplementary edging rolling)". This auxiliary edging rolling, after the reduction of the web thickness reduction and flange width direction is performed by a flat shaped rolling to be put back into edging caliber, the material to be rolled flange width is shortened to edging grooved not filled, deterioration of passing material of the deterioration and the material to be rolled shape is concerned. Such degradation of auxiliary edging passing material worsening and the rolled material shape during rolling, the rolled material is large, and in particular more pronounced in the case of producing large H-shaped steel products of a web height there is likely to be.
[0011]
　Technology disclosed in Patent Document 1 is a technique for reducing the length of the crop portions, the technical concept such shaping the large material to be rolled flange width not disclose any, the "auxiliary edging rolling" that and performing, no mention is about worsening of passing material of the deterioration and the material to be rolled shape in question at that time. Further, disclosed in Patent Document 2, the convex portion is formed in the center of the web corresponding section, then, subjected to rolling for tentering to planarize the protrusion of the central web corresponding section, then make the material to be rolled Te in the art such as performing edging rolling, each time to form a protrusion in the center of the web corresponding section, the convex portion adopts a process such to flatten, an increase in caliber between the transfer times of the material to be rolled is a concern, especially, when a plurality of times the "auxiliary edging rolling" is increased grooved transfer times becomes remarkable, the rolling efficiency is a problem it decreases.
[0012]
　In view of the above circumstances, an object of the present invention performs soft reduction rolling reversed the material to be rolled to the edging caliber after forming the ridge on the web in a flat shaped rolling, in the "supplementary edging rolling", passing material the deterioration of the sexual degradation and the material to be rolled shape is suppressed, and to provide a method for producing a supplemental edging rolling stabilization can be achieved an H-shaped steel.
Means for Solving the Problems
[0013]
　To achieve the above object, according to the present invention, the rough rolling step, an intermediate rolling step, the manufacturing method of the H-shaped steel having a finish rolling step, the rough rolling process, the predetermined the material to be rolled and edging rolling step of rolling shaped into dogbone shape to form a raised portion on the web portion center of the material to be rolled with the material to be rolled after edging rolling process completing rotated 90 ° or 270 ° is rolling the web portion , supplementary to perform a raised portion forming step, the return put soft reduction rolling said one or more passes in the raised portion forming step rolled material to be rolled is rotated again 90 ° or 270 ° in the final caliber of the edging rolling process and edging rolling step, the raised portion formed in the raised portion forming step to pressure the anda ridge erasing step of erasing, vertically grooved roll for performing the ridge generation step, the material to be rolled U Recess to form a raised portion on the blanking portion center is provided in the roll barrel length middle portion of the upper and lower grooved roll, roll shape of the upper and lower grooved roll, so that the flange tip of the rolled material is a non-contact designed, the two steps of the raised portion forming step and the supplemental edging rolling process is performed one or more times continuously, the raised portion erasing step, the ridge forming step and the supplemental edging rolling process line characterized in that it is carried out after cracking, the production method of the H-beams is provided.
[0014]
　Wherein the auxiliary edging rolling process, in the final caliber of the edging rolling step flange portion leading end of the rolled material may be performed soft reduction rolling to fill in the hole type.
[0015]
　Wherein the auxiliary edging rolling process, the auxiliary edging than the web height of the rolled material supplied to the caliber of performing the raised portion forming step immediately before the rolling process, so that the web height of the rolled material is reduced in it may be subjected to soft reduction rolling.
[0016]
　The auxiliary edging rolling process may be performed by one chance or chance when multiple paths set to the edging height of the final pass was fixed was set to 1 chance.
[0017]
　Width of the ridges formed in the raised portion forming step may be set to 50% or less than 25% of the web portion method of the rolled material.
The invention's effect
[0018]
　According to the present invention performs the rolled material soft reduction rolling reversed to edging caliber after forming the ridge on the web in a flat shaped rolling, in the "supplementary edging rolling", deterioration of passing material properties and the to suppress deterioration of the rolled material shape, it is possible to stabilize the supplemental edging rolling.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019]
FIG. 1 is a schematic illustration of a production line of H-shaped steel.
FIG. 2 is a schematic illustration of a first flat shaped caliber.
3 is a schematic illustration of a second flat shaped caliber.
It is a schematic view of the final hole type [4] of the rough rolling step in the production of H-section steel edging rolling process.
It is a schematic illustration for supplemental edging rolling between the [5] edging final pore type and general flat shaped caliber.
6 is a schematic illustration of a supplementary edging rolling according to the present embodiment.
[Figure 7] upon multiple paths elapsed when flat shaping rolling is a graph showing a change in the flange width of the rolled material A per pass.
[8] The first flat shaped caliber, the second flat shaped grooved, and flange width in the case of shaping the H-shaped coarse profile by rolling shaping of a total of 18 passes using three widening grooved in the subsequent stage is a graph showing the transition.
[9] based on the data of FIG. 8 is a graph showing the relationship between the flange width increase or decrease of the relief rate and H-shaped coarse profile after molding.
DESCRIPTION OF THE INVENTION
[0020]
　It will be described below with reference to the drawings, embodiments of the present invention. In the specification and drawings, components having substantially the same function and structure are a repeated explanation thereof by referring to the figures.
[0021]
　(Outline of the manufacturing line)
　FIG. 1 is an explanatory view of a manufacturing line T of H-beam comprising rolling equipment 1 according to this embodiment. As shown in FIG. 1, the production line T in order from the upstream side, the heating furnace 2, the sizing mill 3, the roughing mill 4, the intermediate universal rolling mill 5, finishing universal rolling mill 8 are arranged. Further, edger rolling mill 9 is provided near the intermediate universal rolling mill 5. In the following, the steel in the manufacturing line T for explanation, collectively described as "the rolled material A", sometimes illustrated with the shape dashed-hatched, or the like as appropriate in each figure.
[0022]
　As shown in FIG. 1, the production line T, (the material to be rolled A after) the rectangular cross-section material, for example a slab 11 which has been extracted from the heating furnace 2 is rough rolled in the sizing mill 3 and roughing mill 4. Then, the intermediate rolling in the intermediate universal rolling mill 5. At the time of intermediate rolling, rolling with respect to the flange tip of the material to be rolled (flange corresponding portion 12) is performed by the edger rolling mill 9 as needed. In the usual case, the roll sizing mill 3 and roughing mill 4, Atsushi reduced edging caliber and web portion, so-called flat shaped caliber is engraved for forming the shape of the flange portion. These sizing mill 3 and roughing mill 4 H-shaped coarse profile 13 in the reverse rolling multiple passes through the are shaped. Using rolling mill train comprising the H-shaped coarse profile 13 from the two rolling mill of the intermediate universal rolling mill 5 edger rolling mill 9, reduction of multiple paths is added, the intermediate member 14 is shaped. The intermediate member 14 is finish rolled to a product shape in the finish universal rolling mill 8, H-shaped steel product 16 is produced.
[0023]
　Here, a slab thickness of the slab 11 being extracted from the heating furnace 2, for example, is within 310mm below the range of 290 mm. This is the dimension of the slab material, so-called 300 thick slabs used for manufacturing a large-sized H-beams products.
[0024]
　In the sizing mill 3 and roughing mill 4 shown in FIG. 1, first as the former step, edging rolling process is performed. The edging rolling process performs rolling molding in a state of upright rectangular cross-section material (slab 11) are shaped so as to have a predetermined substantially dogbone shape.
　Following the edging rolling process, the flat shaping rolling process is carried out as a subsequent step. The flat shaped rolling process, the rolled material A is passed through the edging rolling process First, rotated 90 ° or 270 °. This rotation, in edging rolling flange portion located at the upper and lower ends of the rolled material A (slab 11), the arrangement such that the rolling pitch line. Then, rolling the web portion is a connecting portion connecting the flange portions of two places. These edging rolling and flat shaped rolling step, H-shaped coarse profile 13 shown in FIG. 1 is shaped.
[0025]
　Generally it is referred to as rough rolling step together the former step and the latter step. In the production method of the H-shaped steel according to the embodiment, in the rough rolling step, a former step edging rolling process it is sufficient generally carried out by methods known from the prior art. Therefore, in this specification, detailed description of the edging rolling process is omitted. Hereinafter, the flat shaped rolling process which is a subsequent process with reference to the accompanying drawings.
[0026]
　(Caliber configuration Summary)
　2 and 3 are used flat shaping rolling process, a schematic illustration of a first flat shaped grooved KH1 and second flat shaped grooved KH2. The first flat shaped grooved KH1 consists on grooved rolls 85 and the lower grooved roll 86 are a pair of horizontal rolls. As shown in FIG. 2, the first flat shaped grooved KH1, edging rolling the rolled material A which has been rolled shaped in step is rotated 90 ° or 270 °, until the former step the upper and lower ends of the rolled material A flange portion 80 which has been located is the arrangement so that the rolling pitch line. Then, in the first flat shaped grooved KH1, reduction of the web portion 82 is a connecting portion connecting the two flange portions 80 are performed.
[0027]
　Here, the upper and lower grooved rolls 85 and 86 of the first flat shaped grooved KH1 has become a predetermined recess 85a of the length L1, and 86a are formed shape in its roll barrel length middle portion. The grooved structure shown in this FIG. 2, pressure of the web portion 82 is partially performed. As a result, the web portion 82 after reduction, the pressure portion 82a of the web height direction both ridges 82b of the non-pressure portion at the center thereof is formed. Thus, in the rolled material of a so-called dog-bone shape rolling shaped to form the raised portion 82b to the web portion 82 is performed. In this specification, it describes a process for forming a ridge portion 82b on the web portion 82 as "ridge forming step" in the first flat shaped grooved KH1.
[0028]
　In the first flat shaped caliber KH1, the web portion 82 partially pressure, since the rolled shaped as to form a raised portion 82b is carried out, the hole type is "web portion rolling caliber "both are referred to. Width length recess 85a of the formation after the raised portion 82b, the same length as the width length L1 of 86a. Here, as shown in the enlarged view of FIG. 2, the recessed portion 85a in the present specification, the width length L1 of the 86a, the width length of 1/2 of the depth of the recess portion 85a, 86a of the depth hm Satoshi be defined. Also relief amount L1 to be described later are by similar provision.
[0029]
　Figure 3 is a schematic illustration of a second flat shaped grooved KH2. The second flat shaped grooved KH2 consists grooved roll 95 and the lower grooved roll 96 on a pair of horizontal rolls. In the second flat shaped grooved KH2, to the material to be rolled A which is rolled shaped in the first flat shaped grooved KH1, it erases the ridges 82b formed in the web portion 82, and, among the web portion 82 law rolled shaped such that widening is carried out.
[0030]
　In the second flat shaped grooved KH2, rolling to abut against the upper and lower grooved rolls 95 and 96 on the raised portion 82b formed on the web portion 82 pressure the ridges 82b (erase) is performed. With the pressure of the raised portion 82b, the metal flow of the spreading and the flange portion 80 of the web height direction is promoted. Such metal flow, it is possible to carry out rolling shaped into without causing as much as possible rise to flange area reduction. In this specification, the step of rolling (erase) a raised portion 82b in the second flat shaped grooved KH2 also referred to as "ridges erasing step". Further, the second flat shaped grooved KH2, since erasing the ridges 82b formed in the web portion 82, also referred to as "ridges Clear caliber".
[0031]
　Relates rolled modeling in the first flat shaped grooved KH1 and second flat shaped grooved KH2, the detailed conditions for (caliber size and shape, etc.) is based on the knowledge or the like by the present inventors obtained, the It will be described in more detail in the description in the embodiment.
[0032]
　For these first flat shaped grooved KH1 and second flat shaped grooved KH2 H-shaped coarse profiles 13, which is shaped through rolling mill train consisting of the intermediate universal rolling mill 5 edger two rolling mills of the rolling mill 9 using reverse rolling multiple passes are added, the intermediate member 14 is shaped. The intermediate member 14 is finish rolled to a product shape in the finish universal rolling mill 8, H-shaped steel product 16 is produced (see FIG. 1).
[0033]
　The rough rolling step in the production of H-beams, upon performing edging rolling and flat shaped rolling step, as described above, after the thickness reduction of the web portion, the material to be rolled in succession again edging grooved thereto It reversed the a, it is known to carry out the "auxiliary edging rolling" in order to prevent the chewing out from the outer surface position of the material to be rolled flange portion of the flat shaped grooved. The "auxiliary edging rolling" is a technique that has been made than before the shape shaping and unsteady portion of the material to be rolled, the chewing out of shape defects such as suppression such purposes.
[0034]
　(Previous supplementary edging rolling)
　First, FIG. 4, will be described briefly prior supplementary edging rolling with reference to FIG. Figure 4 is a final caliber KE edging rolling the rough rolling step in the production of H-beams (hereinafter, also referred edging final caliber KE) is a schematic view of a. As shown in FIG. 4, edging final caliber KE is engraved on the grooved roll 50 and the lower grooved roll 51 are a pair of horizontal rolls. Circumferential surface of the upper grooved roll 50 (i.e., the grooved top surface), the projections 55 projecting toward the inside caliber is formed. Further, the peripheral surface of the lower grooved roll 51 (i.e., the caliber bottom surface), the projections 56 projecting toward the inside caliber is formed. These projections 55 and 56 has a tapered shape, the dimensions of the projecting length and the like are configured equal to each other between the protrusion 55 and the protrusion 56.
[0035]
　As shown in FIG. 4, the edging final caliber KE, performs the reduction of the web width direction in an upright state the rolled material A, tentering flange is made. Specifically, the upper and lower grooved roll 50 and 51 is formed of the protruding portions 55 and 56, for rolling the outer surface (upper and lower end surfaces of the rolled material A) of the flange portion 80.
[0036]
　In conventional H-shaped steel production techniques, the material to be rolled A which has passed through the edging final caliber KE shown in FIG. 4 is introduced into a general flat shaped grooved, thickness reduction of the web portion is performed. Figure 5 is a schematic illustration for supplemental edging rolling between the edging final caliber KE and general flat shaped grooved GH, (a) ancillary edging rolling before the implementation, auxiliary is (b) edging represent during rolling implementation. As shown in FIG. 5 (a), in general flat shaped grooved GH, reduction in the width direction of the flange portion 80 at the same time as the down web portion thickness of the rolled material A it is also performed. Therefore, as shown in FIG. 5 (b), the width length of the flange portion 80 is considerably shorter. As a result, the material to be rolled A width length with a short flange portion 80 is returned to the edging final caliber KE for ancillary edging rolling.
[0037]
　As shown in FIG. 5 (b), when the material to be rolled A width length with a short flange portion 80 is reintroduced into the edging final grooved KE, flange portion 80 is not selected in the edging final pore type KE the filling state (see the broken line enclosing portion in Figure 5 (b)). The unfilled flange portion 80 within such caliber, lateral centering of the failure and web buckling during rolling, poor dimension such lateral wall weight imbalance of the flange portion 80, the phenomenon shape defects are likely to occur There has been a problem.
[0038]
　(Supplementary edging rolling according to the present embodiment)
　In contrast, in the present embodiment, the flat shaped caliber used during auxiliary edging rolling is a first flat shaped grooved KH1 shown in FIG. 2, "web portion and rolling hole type ". In addition, further, the width shrinkage of the flange portion 80 of the rolling shaping by the web portion rolling caliber defines the smallest such suitable conditions. Accordingly, upon re-introduction of the material to be rolled A to edging final caliber KE, caliber unfilled does not occur. Figure 6 is a schematic illustration of a supplementary edging rolling according to the present embodiment, (a) ancillary edging rolling before the implementation, the (b) represents the time of ancillary edging rolling implementation.
[0039]
　As shown in FIG. 6, the first flat shaped caliber KH1 accordance with the present embodiment, when the down web thickness, the ridges 82b are generated. Thus, the pull-down does not easily occur in the flange portion 80, the reduction rate of flange width decreases. Therefore, as shown in FIG. 6 (b), the width length of the flange portion 80 does not become almost small. Since the change in the flange width is small, it is returned to the edging final caliber KE, binding grooved sidewall portion when the auxiliary edging rolling is performed is maintained. Therefore, a lateral centering property is satisfactory, also web buckling, poor dimension such lateral wall weight imbalance of the flange portion 80, the shape defect is suppressed. In this first pass of the first flat shaped grooved KH1, the tip of the flange portion 80 during rolling shaping is shaped such that a non-contact with the grooved, flat shaped rolling before auxiliary edging rolling (i.e., just flange tip at the raised portion forming step) it is desirable that the roll designed as to contact the roll caliber. In such conditions by implementing supplementary edging rolling caliber filling property when returning the material to be rolled A rises to edging final caliber KE, improving rolling stability is achieved.
[0040]
　During auxiliary edging rolling, preferably, for example, about 40mm or less edging rolling is carried out, in this case, flange width spread value is about 24mm or less.
　Meanwhile, at the time of flat shaped rolling, to the caliber width of a first flat shaped grooved KH1 "web portion rolling caliber" length W (see FIG. 2), taking minimize the web height of the rolled material A it is, it is possible to increase the distance between the outer surface and the grooved roll outer wall of the flange portion 80. Thus, with respect to spreading of the material to be rolled A to web height direction due to the web rolling reduction during flat shaped rolling it can be carried out is rolled with a margin for sliding down scratches by grooved roll outer wall. From this point of view, edging amount when auxiliary edging rolling is desirably as large as possible.
[0041]
　On the other hand, in order to improve the rolling stability in the flat shaped rolling, it is required to increase the caliber binding of the material to be rolled A. It relates caliber binding, as the take Taking large distance between the grooved roll walls and the material to be rolled A flat shaped caliber, and, as the take Taking large widening of the web in the process, induced decreases , rolling becomes unstable. Thus from the viewpoint of a passing material properties, edging amount at the time of supplemental edging rolling is desirably taken as small as possible.
[0042]
　For the reasons described above, the optimum value of the edging amount during auxiliary edging rolling should be determined in consideration of the balance between generation and rolling stability of flaws. When performing a flat shaped rolling after completion auxiliary edging rolling, it is desirable to design such that the side walls of the flat shaped grooved (outer wall) and the web height of the rolled material A coincide substantially.
[0043]
　Here, Mitateru rolled web portion 82 and the plate rolling. From the dimensional relationship of regular shaped steel rolling mill roll diameter and the material to be rolled for large H-shaped steel, the plate width ratio is 3-4 mm, ItaAtsuhi is about 4-5. Further spread amount increases to further having a flange portion in the thickness across. As a result, the web height direction of spreading rate of the rolled material A by the web pressure is 4% or more of the web height. That is, when, for example, the web height as large H-beams are considered the rolled material A such that 1000 mm, spread rate of the web height is at least 40 mm. Therefore, as a condition not in contact with the grooved roll outer wall of the flat shaped caliber, in view of the passing material, etc. by performing edging amount 40mm or more to be spread value or more web height at the time of flat rolled upon ancillary edging rolling for, the roll exit side of the flat shaped rolling a state in contact with the grooved side wall, it will not impair the passing material properties. That is, edging amount when auxiliary edging rolling is preferably 40mm or less.
[0044]
　Also, the flange width spread due to edging rolling can be applied width spread rolling characteristics by slab edging is. In other words, the flange width spread characteristics according to the conventional slab edging method using the caliber having a protrusion in the center of the so-called box caliber is applied. In this case, it is calculated from the approximately 60% of at least about rolling reduction below is known to be a flange width spread, 40mm × 0.6 (60%) = 24mm and.
[0045]
　Figure 7 is a graph showing the time of the plurality of paths elapsed when flat shaping rolling, the transition of the flange width of the rolled material A per pass. The example of FIG. 7 shows the data obtained when performing the FEM calculation as a material of 2000 mm × 300 mm cross-section slabs. In Figure 7, the flat shaped rolling in the conventional general planar shaped grooved GH (hereinafter, referred to as "conventional method") and the flat shaping rolling at the first flat shaped grooved KH1 according to the present embodiment ( hereinafter referred to as "the present method") are compared.
　As shown in FIG. 7, the reduction rate of the flange width by flat shaped rolling according to the present embodiment was less than the reduction ratio of the flange width by the conventional method. For example, after the flat shaped rolling 13 pass course, the difference between the flange width by each of the flat shaped rolling was 100mm or more. From the results of FIG. 7, the flat shaped rolling according to the first flat shaped grooved KH1 according to the present embodiment, the reduction rate of the flange width is reduced, the caliber unfilled during auxiliary edging rolling is suppressed There can understand.
[0046]
　The present inventors have found that different supplementary edging passing material properties depending on the filling of the grooved during rolling, when a grooved unfilled is a problem with the passing material properties was also confirmed by experiment . Table below 1 are experimental examples showing the relationship between a grooved filling property and passing material properties in auxiliary edging rolling. Table 1, in the conventional method and the present invention method under the condition of Case 1 to Case 4, shows the relationship between the grooved filling property and passing material properties. At the time of supplemental edging rolling, in all cases 1-4 were subjected to edging rolling the edging weight of about 40mm in two passes. Therefore, the value of the web height change during auxiliary edging rolling shown in Table 1 is represented with -40mm in all cases 1-4.
[0047]
[Table 1]

[0048]
　As shown in Table 1, at the time of supplemental edging rolling, if the caliber is full, through material was good. In contrast, when the caliber is not yet filled, bending has occurred. Referring also to the case 2-4, in the conventional method and the present invention method, auxiliary edging when taking a same cumulative web rolling reduction during rolling, the accumulated web reduction ratio such that the grooved nonfilled the conventional method even, filled is grooved in the present invention method, there is the passing material properties are well maintained (see case 2 in Table 1). Incidentally, since the time of supplemental edging rolling it was to subject the edging rolling about 40 mm, a web height value when auxiliary edging rolling shown in Table 1 has a -40mm in all cases 1-4.
[0049]
　Then, the present inventors have by the schedule design auxiliary edging rolling according to the present embodiment (reduction rate and pass schedule, etc.), was considered the effect of suppressing the defective dimension and shape defects are different. Therefore, in the case of producing the H-shape steel 2000 mm × 300 mm cross-sectional slab as a material, and the transition of the flange width by auxiliary edging rolling verified experimentally.
[0050]
　Table 2 below shows the time of implementing the flat shaped rolling according to the first flat shaped grooved KH1 (i.e. web portion rolling caliber), the transition of the flange width of each path. Table 2 Case 1-3, the number of times of performing the auxiliary edging rolling for each path of the flat shaped rolling different. In case of performing the auxiliary edging rolling (i.e. cases 2 and 3), the transition of the flange width after performing auxiliary edging rolling is shown. Further, according to the 15th pass, second 23 pass in the table is indicative that the edging rolling at the preceding stage as the first to fourteenth path is performed before the flat shaping rolling, the 15th or later path shows that it is a flat molding rolling.
　During auxiliary edging rolling, it was subjected to edging rolling about 40 mm. Specifically, in Case 2 was carried out once edging rolling about 40mm in two passes. In Case 3, it was edging rolling about 20mm in 2 pass twice in a row. As shown in Table 2, spread value of the flange width by auxiliary edging rolling, in Case 2, in about 24 mm, Case 3 in any of the paths, was also about 44mm in any of the paths.
[0051]
[Table 2]

In Table 2, "Case 2: auxiliary edging rolling once": auxiliary edging description "Case 3 auxiliary edging rolling 2 times", that is carrying out the two-pass as a set indicates the number of rolling, notation auxiliary edging rolling number of times of the two-pass one set is denoted as "1 chance", "2 chance". In practice, 1 auxiliary edging number of rolling passes is may be in a single pass of chance, but may be a plurality of more than two passes, edging the total amount of certain conditions (i.e., the final pass edging height of path schedule is designed as a condition for a constant).
　Further, Table 2, which lists flange width changes at each pass in the case of performing the flat shaped rolling an auxiliary edging without rolling as Case 1 for reference.
[0052]
　Case 2 of Table 2, in each pass as shown in case 1, the auxiliary edging rolling only 1 chance in each pass, shows the flange width after under conditions that do not restrict the expansion of the flange width.
　As shown in Table 2 of the case 2, when performing auxiliary edging rolling in 1 chance, auxiliary edging flange width after rolling before flat shaped rolling edging caliber width at 15th pass to seventeenth path (1010 mm ) it was more than the. Therefore, the caliber filling is achieved in the edging final caliber KE when auxiliary edging rolling. Those in Table 2 are described as "○" is grooved fill is realized, rolling stability is indicated better.
　Meanwhile, since the flange width after supplementary edging rolling eighteenth subsequent passes is below the flat shaped rolling before edging caliber width (1010 mm), edging final caliber KE becomes unfilled when auxiliary edging rolling, dimensional error, there is a possibility that the shape defect occurs. Those in Table 2 are described as "×" indicates a problem with the rolling stability becomes caliber unfilled.
[0053]
　Further, the present inventors, the table 2 of the case 3 are shown as auxiliary edging rolling 2 Chance: was verified also when performed in (in the table auxiliary edging rolling twice). The case 3, in the 18 subsequent path becomes a case 2 in the grooved unfilled, increased auxiliary edging rolling times, after an auxiliary edging rolling under conditions that do not restrict the expansion of the flange width 2 Chance shows the flange width.
　When performing auxiliary edging rolling in 2 chance ancillary edging the flange width spread during rolling can be expected greatly compared with the case of 1 chance, more in subsequent passes when auxiliary edging rolling Edging final caliber hole in KE mold filling can be achieved. In this verification conditions, as shown in Table 2, the caliber filling is achieved in the edging final caliber KE when auxiliary edging rolling up to the 22 path.
　Generally, auxiliary edging rolling is desired to be stably performed in later stage path of the flat shaped rolling. This auxiliary edging enough to implement the rolling improves the material to be rolled shape dimensional accuracy of sending the intermediate rolling and finish rolling is more subsequent step, rolling stability and product dimensional accuracy in subsequent pass of the flat shaped rolling This is because the improvement of is achieved.
　That is, the auxiliary edging rolling by performing in two chance, without causing defective dimension and shape defects of the rolled material, more ancillary edging rolling at a later stage is achieved, that the efficiency of the rolling can be achieved Understand.
[0054]
　Further, reference, Table 3 below changes in flange width after flat shaped rolling in the conventional method (the case 1), the flange width when the auxiliary edging rolling after the auxiliary edging rolling after each pass It illustrates transition of the flange width considering the spread of (case 2). As shown in Table 3, in the conventional method, the flange width after only auxiliary edging rolling in the fifteenth path is above a flat shaped rolling before edging caliber width (1010 mm), edging final hole when auxiliary edging rolling caliber filling is realized in the mold KE. Meanwhile, since the sixteenth pass beyond the flange width after auxiliary edging rolling is below the flat shaped pre-rolling of the flange width (1010 mm), when the auxiliary edging rolling edging final grooved KE becomes unfilled, dimensional error , there is a possibility that the shape defect occurs.
[0055]
[table 3]

[0056]
　Table 2 and as can be seen by comparing Table 3, when applying the present invention method, auxiliary edging rolling was realized caliber filled up to the 17 paths implemented in the case of performing the auxiliary edging rolling only 1 chance It was possible. When performing auxiliary edging rolling in 2 chance supplementary edging rolling was realized caliber filling was feasible until the 22 path. In contrast, in the conventional method, only to the 15th pass was realized caliber filled auxiliary edging rolling could not be performed. That is, the present invention method can further exemplary ancillary edging rolling later paths by applying, by suppressing the defective dimension and shape defects such as occurrence of flaws, it is possible to carry out the rough rolling step with high precision .
[0057]
　(The ratio of the relief amount of the first flat shaped grooved KH1 (ridge formation width))
　As described above, in the first flat shaped grooved according to the present embodiment KH1 (see FIG. 2), the rolled material A ridge 82b is formed in the center of the web portion 82. The formed ridge 82b is erased in the second flat shaped grooved KH2 subsequent stage. The widening rolled web in process is performed as needed after ridges erase, H-shaped coarse profile is shaped.
[0058]
　The present inventors have found that the width length of the raised portion 82b to form the first flat shaped grooved KH1 L1 (i.e., an amount relief of the web in the method in the rolling shaping of the first flat shaped caliber KH1. Or less, by simply changing the.) referred to as a "relief amount", found that differences enters the flange width of the H-shaped coarse profile finally obtained. This is the flange wall volume is likely to ensure the larger the width length L1 of the raised portions 82b, on the other hand, the flange width decreases by a longitudinal stretching action of the rolled material A at the ridges erasing after caused by.
　Accordingly, the present inventors have examined the relationship between the relief amount and of the web in the method in the rolling shaping of the first flat shaped grooved KH1, the flange width of the finally obtained H-type roughness profile.
[0059]
　8, the first flat shaped grooved KH1 according to the present embodiment, the second flat shaped grooved KH2, and, H Katachiara further by rolling shaping of a total of 18 passes using three widening grooved in the subsequent stage in the case of shaping the profile is a graph showing a change in the flange width of each path. 8 shows a data using material slabs of approximately 2000mm wide.
　Further, although the horizontal axis and 1-18 path in the graph of FIG. 8, of which 1-13 path corresponding to the first flat shaped grooved KH1, 14, 15 pass corresponds to the second flat shaped grooved KH2 , 16-18 path corresponds to the caliber of the widening rolling.
[0060]
　Further, in FIG. 8 describes the respective data when changing the relief amount L1. In Figure 8, to define the values shown in equation (1) below as a relief rate, the relief rate of 12%, 17%, 23%, 28%, 33%, 39%, 44%, in the case of 49% data were reported, the relief rate describes the case of 0% as the conventional method.
Relief rate [%] = (relief amount L1 / web inside dimension L2) × 100 ··· (1)
[0061]
　Meat shrinkage amount in the flange portion 80 in the first flat shaped grooved KH1 (reduction of flanges meat weight) is reduced by increasing the escape rate. Therefore, as shown in FIG. 8, the flange width of the finally obtained H-type roughness profile it is tends to increase with increasing relief rate. This trend, as shown in FIG. 8, was also observed experimentally. However, the flange width after a ridge erase or widening rolling in the subsequent second flat shaped grooved KH2, the flange width and larger than a predetermined value in the relief rate was not become necessarily large. This is because when increasing the relief portion is estimated to be due to the flange wall shrinkage amount at the time of ridges erased in the second flat shaped grooved KH2 is expanding.
[0062]
　That is, considered as a manufacturing process of a large H-shaped steel, in case of adopting a method such as to form a raised portion 82b described in the present embodiment, the relief rate shall preferable range exists It is. The present inventors focused on the relationship between the increase and decrease of the flange width of the relief rate and H-shaped coarse profile after molding, derived preferred numerical range of the relief rate.
[0063]
　9, based on the data of FIG. 8 is a graph showing the relationship between the relief rate and H-shaped coarse profile shaped post flange width change rate of. Note that the flange width change ratio in FIG. 9, as a reference (1.000) a flange width when the relief ratio is 0%, when the relief ratio is the value (12% -55%) flange width is a value that shows the.
[0064]
　As shown in FIG. 9, in the area ratio is small relief, tended to increase the flange width of the H-shaped coarse profile as relief ratio increases. However, flange width change rate in the region rate is about 50% less than about 25% relief was nearly constant value (refer to a broken line portion in FIG. 9).
　From the results shown in FIG. 9, when manufacturing large large H-beams products flange width compared with the prior art, considering that the rolling shaped as flange width also increases the H-shaped coarse profile is desired, relief numerical range rate is found to be desirable to be 25% to 50%. Further, in the rolling shaping process, Dari prevent increase in the rolling load, from the viewpoint of enhancing production efficiency, since it is preferred that relief rate to as low as possible, it is desirable that the relief ratio is set to about 25% .
[0065]
　(Operation and Effect)
　described above, according to the manufacturing method of the H-shaped steel according to the present embodiment, using a flat shaped rolling performed after edging rolling, the first flat shaped grooved KH1 to form a raised portion 82b used has implemented. Thus, performing the putting back the material to be rolled A soft reduction rolling edging final caliber KE after flat shaping rolling, in the "supplementary edging rolling", by suppressing the deterioration of the passing material worsening or material to be rolled shape , it is possible to stabilize the supplemental edging rolling. Further, it is possible to roll shaping the large H-roughness profile 13 of the flange width than conventional and will, it is possible to manufacture a large H-beams products flange width than conventional consequently.
[0066]
　Further, for example, when performing rolling molding H-shaped coarse profile according to the present embodiment about the thickness 300mm called 300 thick slab, the material having a width of about 2000mm based, at flat shaped rolling, so-called "web portion rolled upon use of the first flat shaped grooved KH1 is a hole type ", (more preferably about 25%) within the relief ratio of 25% to 50% in the formation of the raised portion 82b by setting the, rolled shaped flange width of the H-shaped coarse profiles it is possible to maximize that.
[0067]
　Having described an example of an embodiment of the present invention, the present invention is not limited to the illustrated form. Those skilled in the art within the scope of the spirit as set forth in the appended claims, it is intended to cover various modifications and changes naturally fall within the technical scope of the present invention also for their things to be understood.
[0068]
　For example, in the above embodiment, as a preliminary step to implement a flat shaped rolling using a first flat shaped grooved KH1, described as performing flat shaped rolled rectangular section material the slabs after rolling shaped by edging rolling but the application range of the present technique is not limited thereto. That is, even the present technique when performing flat shaped rolling to the rolled material which has not undergone edging rolling process as a beam blank is applicable.
Industrial Applicability
[0069]
　The present invention can be applied to, for example, a method of manufacturing the H-shape steel slab like a rectangular cross-section as a material.
DESCRIPTION OF SYMBOLS
[0070]
　1 ... rolling equipment
　2 ... furnace
　3 ... sizing mill
　4 ... roughing mill
　5 ... intermediate universal rolling mill
　8 ... finishing universal rolling mill
　9 ... edger rolling mill
　11 ... slab
　13 ... H-shaped coarse profiles
　14 ... intermediate member
　16 ... H-shaped steel product
　50 ... upper grooved roll (edging final
　caliber) 51 ... lower grooved roll (edging final pore
　type) 55 and 56 ... protrusion (edging final
　caliber) 80 ... flange portion
　82 ... web portion
　82a ... pressure part
　82b ... ridges (not pressure
　portion) 85 ... upper grooved roll (first flat shaped
　grooved) 85a ... recess
　86 ... lower grooved roll (first flat shaped
　grooved) 86a ... recess
　95 ... upper grooved roll (second flat shaped grooved)
　96 ... lower grooved roll (second flat shaped grooved)
　KH1 ... first flat shaped grooved
　KH2 ... second flat shaped grooved
　KE ... edging final pore type
　GH ... common flat shaped grooved
　T ... production line
　A ... a material to be rolled

WE claims

Rough rolling process, a process for the preparation of the intermediate rolling step, the finishing H-shaped steel having a rolling step,
said rough rolling step, a edging rolling step of rolling shaping the material to be rolled into a predetermined dogbone shape,
edging rolling the process after completion of the rolled material is rotated 90 ° or 270 ° to form a raised portion on the web portion center of the material to be rolled performs rolling of the web portion, and the ridge forming step,
1 by the ridge generation step and auxiliary edging rolling process of the material to be rolled was rolled over path by rotating again 90 ° or 270 ° returning is performed put soft reduction rolling to a final caliber of the edging rolling step,
formed in the raised portion forming step has a ridge erasing step of rolling ridges erased, and
the upper and lower grooved roll for performing the ridge generation step, recess to form a raised portion on the web portion center of the material to be rolled is the Provided to the roll barrel length middle portion of the lower grooved roll,
roll shape of the upper and lower grooved roll is designed as a flange portion leading end of the rolled material is a non-contact,
it said raised portion forming step and the supplemental edging 2 step rolling process is performed one or more times continuously,
the raised portion erasing step is characterized in that it is carried out after the ridge forming step and the supplemental edging rolling process is performed, H method for producing a shape steel.
[Requested item 2]
Wherein the auxiliary edging rolling process, characterized in that in the final caliber of the edging rolling step flange portion leading end of the rolled material performs soft reduction rolling to fill in the hole-type, according to claim 1 method of manufacturing the H-shaped steel.
[Requested item 3]
Wherein the auxiliary edging rolling process, the auxiliary edging than the web height of the rolled material supplied to the caliber of performing the raised portion forming step immediately before the rolling process, so that the web height of the rolled material is reduced and performing soft reduction rolling method of H-shaped steel according to claim 2.
[Requested item 4]
The auxiliary edging rolling process, characterized in that it is implemented by one chance or chance when multiple paths set to the edging height of the final pass was fixed was set to 1 chance of claims 1 to 3, method of manufacturing H-shaped steel according to any one.
[Requested item 5]
Width of the ridges formed in the raised portion forming step is characterized in that it is set to 50% or less than 25% of the web portion method of the rolled material, according to any one of claims 1 to 4, the method of manufacturing H-shaped steel.