EP0736341A1 - Verfahren zur herstellung von h-stahlträgern - Google Patents

Verfahren zur herstellung von h-stahlträgern Download PDF

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Publication number
EP0736341A1
EP0736341A1 EP95902974A EP95902974A EP0736341A1 EP 0736341 A1 EP0736341 A1 EP 0736341A1 EP 95902974 A EP95902974 A EP 95902974A EP 95902974 A EP95902974 A EP 95902974A EP 0736341 A1 EP0736341 A1 EP 0736341A1
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EP
European Patent Office
Prior art keywords
mill
universal
rolls
horizontal
width
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EP95902974A
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English (en)
French (fr)
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EP0736341A4 (de
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Yoshiaki Sumitomo Metal Industries Ltd. KUSABA
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Nippon Steel Corp
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Sumitomo Metal Industries Ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/08—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling structural sections, i.e. work of special cross-section, e.g. angle steel
    • B21B1/088—H- or I-sections
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/08—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling structural sections, i.e. work of special cross-section, e.g. angle steel
    • B21B1/088—H- or I-sections
    • B21B1/0886—H- or I-sections using variable-width rolls

Definitions

  • the present invention relates to a hot-rolling method for the manufacturing H-section steels having a high dimensional accuracy for use in architecture and building, and more particularly to a hot-rolling method using a group of universal mills for manufacturing H-section steels of various different sizes with a dimensional accuracy comparative to that of welded H-section steels.
  • a steel frame of a building is generally composed of an assembly of H-section steels.
  • H-section steels With a growing tendency toward high-rise buildings, a demand for H-section steels of various different sizes or H-section steels with a high dimensional accuracy has increased.
  • JIS Japanese industrial Standards
  • welded H-section steels are used in many cases for the aforesaid architectural and building purposes.
  • Figure 1 is a view showing the cross-sectional shape of H-section steels and dimensions of various parts of the H-section steels. Designated by H as the height of a web, B the width of flanges, t 1 the thickness of the web, t 2 the thickness of the flanges, and b 1 and b 2 the length or distance from the web and an end of each flange.
  • H500 The nominal size of an H-section steel is represented by H500 ⁇ B200 ⁇ 10/16, for example.
  • H500 represents a web height of 500 mm, B200 a flange width of 200 mm, and 10/16 a web thickness of 10 mm and a flange thickness of 16 mm, respectively.
  • Dimensional tolerances stipulated for the welded H-section steels by the Steel Structure Association Standards are smaller than these of the hot-rolled H-section steels (hereinafter simply referred to as "H-section steels").
  • H-section steels the tolerance allotted to the web height of 500 mm is ⁇ 1.5 mm for the welded H-section steel and ⁇ 3.0 mm for the H-section steel.
  • the web offset is set to be ⁇ 2.5 mm for welded H-section steels having a web height not smaller than 300 mm, and ⁇ 3.5 mm for welded H-section steels having a web height not smaller than 300 mm.
  • a cast iron bloom or a steel bloom is rolled by a two high breakdown mill (hereinafter referred to as 2Hi-BD mill") down into a rough-rolled section piece having a dog-born shape which in turn is rolled down successively by a series of mills composed of a universal roughing mill (hereinafter referred to as "UR mill”), a two high edger mill (hereinafter referred to as “2Hi-E mill”), and a universal finishing mill (hereinafter referred to as "UF mill”).
  • UR mill universal roughing mill
  • 2Hi-E mill two high edger mill
  • UF mill universal finishing mill
  • the 2Hi-E mill has two rolls so grooved as to form a plurality of edger passes or grooves arranged in the widthwise direction of the rolls.
  • edger passes or grooves having different web heights and/or flange widths (H600 ⁇ 200, H550 ⁇ 200 and H500 ⁇ 200 or H200 ⁇ 100, H300 ⁇ 150 and H400 ⁇ 200, for example) are formed in each of the two rolls.
  • Figure 2 is a view showing a plurality of grooves formed in rolls of the 2Hi-E mill and cross-sectional shapes of rolled materials.
  • designated by 5 is an upper edger roll, 6 a lower edger roll, (A) a pass or groove provided for the size of H500 ⁇ 200, (B) a pass or groove provided for the size of H550 ⁇ 200, and (C) a pass or groove provided for the size of H600 ⁇ 200.
  • Figure 3 is a cross-sectional view of a rolled blank piece (3(a)) which changes to an H-section steel (3(c)) to illustrate a method of manufacturing an H-section steel by an edger mill which is composed of a 2Hi-E mill.
  • Figure 3(a) is a view showing the condition in which rough rolling is achieved in a UR mill having an upper horizontal roll 1, a lower horizontal roll 2 and a pair of opposed vertical rolls 3 and 4. At this rolling stage, a rough-rolled shape of the H-section steel is produced.
  • Figure 3(b) is a view illustrative of the condition in which rough rolling is achieved in a 2Hi-E mill having only an upper edger roll 5 and a lower edger roll 6.
  • one pass or groove is shown which is selected from one of the three passes or grooves shown in Figure 2.
  • the accuracy of various dimensions such as the flange width, the web center (the center of the web located centrally between the opposed flanges at each end), and the like is secured.
  • using the rolls 5 and 6, opposite toes 7 of the respective flanges are reduced in cross-sectional shape to correct a web offset of the blank piece being rolled.
  • the inside surfaces of the flanges are brought into contact with the rolls to prevent lateral displacement of the blank piece being rolled.
  • Figure 3(c) is a view showing the condition in which finished rolling is achieved in the UF mill having an upper horizontal roll 8, a lower horizontal roll 9, and a pair of opposed vertical rolls 10 and 11.
  • the inside surfaces of the respective flanges are held in contact with the horizontal rolls 8 and 9, while the outside surfaces of the respective flanges are held in contact with the vertical rolls 10 and 11.
  • an H-section steel of a final product size is obtained.
  • the web center may be offset due to uneven enlargement of the flange width caused by an incorrect biting posture, or misalignment of the upper and lower horizontal rolls.
  • an attempted correction achieved in the subsequent 2Hi-E mill will cause buckling of the flanges due to heavy pressure applied thereto.
  • Figure 4 is a front elevational view of the rolls, with a blank piece being rolled shown in cross section, illustrating an example of buckled flanges in the 2Hi-E mill. Since only part of the flanges are severely bent or flexed, reduction of the flange width and correction of the web offset are difficult to achieve. Accordingly, even if finished rolling is achieved in the succeeding UF mill, the unevenly enlarged flange width remains unchanged or uncorrected. Thus, the web offset can never be corrected.
  • the disclosed UE mill has, however, never been used in practice in any of Europe, the U. S. A. and Japan for the reason described below.
  • this UE mill one pair of horizontal rolls and one pair of vertical rolls are held in full contact with a blank piece being rolled, so each size of blank piece requires one pair of horizontal rolls, thus leading to an increased number of stocked roll sets. This problem becomes significant when H-section steels having a uniform outside dimension are to be manufactured.
  • H-section steel used as a steel frame of a high-rise building is determined according to the load applied thereto. Accordingly, various types of H-section steels having different nominal sizes are produced. In practice, however, H-section steels having one and the same nominal size may have different web lengths and flange widths. When such dimensionally non-uniform H-section steels were used in combination, a difficulty in making a joint would occur, as well as injure the beauty of the resulting steel frame.
  • H-section steels of different nominal sizes requires grooved roll mills or universal mills which are selected in accordance with the desired web heights. Numerous rolling methods have been proposed for the purpose of reducing the number of rolls.
  • the present inventor has already proposed a method of reducing the web height by means of a UF mill (Japanese Patent Laid-open Publication No. 2-84203, U.S. Patent No. 4958509, British Patent No. 2222796, Australian Patent No. 625679 and Korean Patent No. 51420) and a method of reducing the web height either in a UR mill or in UF mill (Japanese Patent Laid-open Publication No. 4-258301, US. Patent No. 5287715, Australian Patent No.
  • Japanese Patent Laid-open Publication Nos. 59-133902, 60-82201, 60-83702, 60-118301 and 62-93008 each disclose a method of reducing the web height in intermediate rolling or finish rolling.
  • a method of enlarging the web height in intermediate rolling or finish rolling is disclosed in Japanese Patent Laid-open Publication Nos. 63-30102, 63-72402, 63-168204, 61-262403 and 62-161403.
  • Japanese Patent Laid-open Publication Nos. 61-262402 and 61-262404 disclose a method of reducing or enlarging the web height.
  • the toes of each flange are not subjected to reduction in cross-sectional area by means of the rolls; rather, the flanges are allowed to enlarge or spread in the widthwise direction. Consequently, when the web height is reduced in particular, a phenomenon is observed that the material flows from the web portion to the flange portion, creating more than 4% enlargement of the flange width which exceeds an allowable tolerance of the flange width.
  • the conventional methods have a problem whereby the web offset can increase even when the web height is changed, as the case may be, and canceling out the correcting effect provided by the edger mill.
  • the H-section steels of the type having a uniform outside dimension are defined as a series of H-section steels which is uniform in the web height H and flange width B but differs from one another in the web thickness t 1 and flange thickness t 2 , as shown in Figures 1(a) and 1(b).
  • An object of the present invention is to provide a method of manufacturing highly dimensionally accurate H-section steels by hot rolling, and more particularly, a method of manufacturing by hot-rolling various types of H-section steels having different nominal sizes or a series of H-section steels having a uniform outside dimension with a dimensional accuracy comparative to that of the welded H-section steels.
  • the gist of the present invention resides in H-section-steel manufacturing methods enumerated in the following paragraphs (1) to (5).
  • Figure 5 illustrates various H-section-steel manufacturing lines used for carrying out the methods of the present invention, whereby Figure 5(a) shows an H-section-steel manufacturing line including a UR mill and a UE mill installed closely one behind the other, Figure 5(b) is a view showing another H-section-steel manufacturing line in which a UR mill, a UE mill and a UF mill equipped with horizontal rolls having a variable width are installed closely one behind another, Figure 5(c) is a view showing still another H-section-steel manufacturing line in which a UR mill and a UE mill equipped with horizontal rolls having a variable width are installed closely one behind the other, and Figure 5(d) is a view showing an H-section-steel manufacturing line including a UR mill, a UE mill and a UF mill installed closely one behind another wherein the UE mill and the UF mill are each equipped with horizontal rolls having a variable width.
  • the term "installed closely” is used herein to refer to a
  • Figure 6 is a front elevational view of rolls in a universal edger mill (UE mill) used in a rolling method of this invention, showing the positional relationship between each roll and a blank piece being rolled shown in cross section.
  • the UE mill is of the universal type having an upper edger horizontal roll 12, a lower edger horizontal roll 13, and two opposed vertical rolls 14 and 15.
  • the horizontal rolls 12, 13 of the UE mill have a roll width L smaller than that of horizontal rolls of the UR mill used provided to perform the preceding rolling process, so that there is defined, jointly between opposed sloped portions or shoulders 21 of the respective roller bodies of the horizontal rolls and the inside surface 22 of a corresponding one of the flanges of a blank piece being rolled, an annular space or gap 16 having a thickness or distance ⁇ by virtue of which the inside flange surfaces 22 of the blank piece being rolled are kept free from restraint by the horizontal rolls. Ends or toes 7 of the flanges are reduced in cross-sectional area by and between the horizontal rolls 12, 13 while the flange outside surfaces 23 are kept under restraint by the vertical rolls 14, 15.
  • a continuously cast slab or bloom (not shown), heated to about 1,250 °C in a heating furnace (not shown), is passed through a 2Hi-BD mill to roll a beam blank which forms a rough H-section steel piece.
  • the beam blank is passed back and forth through a universal mill group (UT) composed of a UR mill and a UE mill.
  • UT universal mill group
  • the beam blank is so shaped or corrected as to attain the desired dimensions.
  • the dimensioned beam blank is then passed through a UF mill which completes an H-section steel of the desired final shape.
  • the UR mill When an H-section steel having a size of H700 ⁇ B200 is to be manufactured, the UR mill employs horizontal rolls having a width L of 676 mm which is provided for the H700 ⁇ B200 size, while the UE mill employs horizontal rolls having a width of 566 mm which is smaller than that of the horizontal rolls of the UR mill. With the horizontal rolls thus employed, it is possible to manufacture H-section steels of different sizes which vary from H700 ⁇ B200 to H700 ⁇ B200.
  • the UE mill in which the inside surface of each flange of the blank piece being roll is held out of contact with the horizontal rolls, is installed close to the UR mill, and the UF mill is installed close to the UE mill.
  • the UF mill can also be used in the intermediate rolling process, one pass through the UR mill and the UF mill will complete a reduction of the thickness two times with the result that the rolling efficiency can be improved by 50% or more as compared with the method shown in Figure 5(a).
  • the length of the rolling line is relatively short so that the overall building length of a rolling plant can be reduced considerably.
  • Figure 7(a) is a view showing the width of rolls in the UE mill shown in Figure 6, and Figure 7(b) is a front elevational view of rolls of the universal finishing mill (UF mill) with a blank piece shown in cross section.
  • reference character 17 denotes a two-piece horizontal roll having a variable width
  • 18 denotes a vertical roll.
  • the UF mill having the variable-width type horizontal rolls shown in Figure 7(b) may be installed close to the UE mill shown in Figure 5(b) to achieve rolling in a manner described below.
  • the horizontal rolls of the UR mill have a roll width of 676 mm (which is equal to an inside dimension of the web of an H-section steel of the H700 ⁇ B200 size), and the horizontal rolls of the UE mill having a width of 566 mm, as shown in Figure 7(a), if the horizontal rolls of the UF mill has a width variable from 676 mm to 576 mm, then it becomes possible to roll three types of H-section steels having different sizes: H700 ⁇ B200, H650 ⁇ B200 and H600 ⁇ B200.
  • Adjustment of the UR mill and the UF mill causes a reduction in the direction of thickness of the web and the flange, while adjustment of the UE mill causes a reduction in the widthwise direction of the flanges. More specifically, a final pass through the UE mill causes a reduction in web height by 50 mm, and after that a final pass through the UF mill, which is achieved after the width of the horizontal rolls is reduced from 676 mm to 626 mm converts the blank piece into an H-section steel having a size of H650 ⁇ B200.
  • the foregoing embodiment relates to the manufacturing of H-section steels having different web heights; however, by properly arranging the mill line, the method of the present invention is able to produce similar H-section steels which are uniform in an outside dimension but differ from one another in flange width. web thickness and/or flange thickness. Since the horizontal roll width of the UE mill is smaller than that of the UR mill, there is a space defined between the inside surface of each flange and the horizontal rolls. This arrangement is able to obviate the need for providing a separate roll mill used exclusively for the purpose of changing the web height.
  • Figure 8 is a front elevational view of horizontal rolls of the type having a variable width and vertical rolls of an UE mill with a blank piece being rolled shown in cross section.
  • the variable-width type horizontal rolls 19 can attain a desired width change on the on-line basis and hence does not require a space 16 (defined partly by horizontal rolls shown in Figure 6) for reducing the web height in a final pass of the intermediate rolling.
  • the horizontal rolls and the vertical rolls jointly define a groove so that the horizontal rolls attain a reduction in cross-sectional area of the toes of flanges while the inside and outside surfaces of the flanges are confined by the horizontal and vertical rolls. With this arrangement a further improvement in the dimensional accuracy can be attained.
  • variable-width type horizontal rolls when used in manufacturing a wide variety of H-section steels of different sizes, provide a substantial reduction in the number of stocked horizontal roll sets of different sizes and a subsequent reduction of roller exchange time. Furthermore, the horizontal rolls are particularly useful when incorporated in a mill line arranged to manufacture H-section steels requiring a uniform outside dimension with high dimensional accuracy.
  • the general 2Hi-E mill has two horizontal rolls so grooved as to form a plurality of edger passes or grooves arranged in the widthwise direction of the rolls.
  • each of the rolls has three edger grooves of different sizes which are provided for H-section steels of (A): H600 ⁇ 200, (B): H550 ⁇ 200 and (C): H500 ⁇ 200, respectively.
  • the horizontal roll width is fixed and not variable, one set of horizontal rolls must be stocked for each of the desired product sizes.
  • the horizontal roll width is variable within a range of 100 mm at maximum, H-section steels having three different sizes of H600 ⁇ 200, H550 ⁇ 200 and H500 ⁇ 200, for example, can be rolled by a single set of horizontal rolls of the variable-width type.
  • the number of variable-width type horizontal roll sets to be stocked can he reduced to a value which is equal to the number of grooved rolls of the general 2Hi-E mill shown in Figure 2.
  • the 2,500-mm-body-length rolls used in a 2Hi-E mill are more than 20 tons in weight.
  • the universal horizontal rolls are about 7 tons in weight, and even when a mechanism for changing the horizontal roller width is provided, the price of the universal horizontal rolls is about 2/3 of that of the rolls of the 2Hi-E mill.
  • Japanese Utility Model Laid-open Publication No. 3-111404 (corresponding to U.S. Patent No. 5154074 and European Patent No. 443725), for example, may be used, which includes a movable sleeve roll having on its outer peripheral surface projections and connected by a sliding key to an arbor, a nut threaded over an externally threaded distal end portion of the sleeve and having circumferentially equidistant projections each adapted to be engaged in a space between two adjacent ones of the projections on the sleeve roll, and a split key axially interconnecting the sleeve roll and the nut at their opposed ends including the projections.
  • the UE mill of the type having a variable horizontal roll width is able to roll H-section steels of various different sizes with high dimensional accuracy.
  • Figure 9 is a view showing the cross-sectional shape of a roughly rolled blank section piece used with the model mills.
  • the blank section piece is formed from stainless steel because stainless steel does not produce any scale at rolling temperatures.
  • Figure 10 is a graph showing measured values of the web offset plotted in the lengthwise direction of the blank section piece and two rolled products produced as a result of the foregoing Experiment.
  • the dash-and-dot lines (E) shown in Figure 10 clearly indicated that as a result of rolling achieved in the conventional edger mill as specified above in the preceding paragraph (2) the web was displaced toward a central portion of the flange by about 1 mm, so that the web offset was corrected or reduced from 1 mm to 0.01 mm.
  • the flange portions were prevented from bucking outwards with the result that the web was displaced toward the center of the flanges by about 1 mm, and subsequently the web offset was corrected or reduced from 1 mm to 0.02 mm, as indicated by the solid lines (F) shown in Figure 10.
  • the web-offset correcting effect attained by the inventive method (3) was substantially the same as that obtained by the conventional method (2) in which the edger mill was used.
  • Figure 11 is a graph showing measured values of the flange width taken in the lengthwise direction of the blank section piece before and after the blank section piece was passed through the UF mill.
  • the broken lines (H) represent variations of flange width observed after rolling in the UE mill
  • the solid lines (J) represent variations of the flange width observed after rolling in the UF mill.
  • variations of the flange width are not large even when a reduction in flange width is attained, and variations of the flange width observed after the UF mill is not greater than ⁇ 0.3% (47.09 mm - 46.79 mm) which is superior in dimensional accuracy to the welded H-section steels ( ⁇ 1.5%).
  • the UE mill shown in Figure 6 was installed in the mill line shown in Figure 5(a).
  • the UE mill had horizontal rolls provided for the H800 ⁇ B300 product and having a horizontal roll width (L) of 750 mm.
  • L horizontal roll width
  • an experiment was conducted to manufacture three types of H-section steels: the first type having a web height of 900 mm, a flange width of 300 mm, a web thickness of 12 mm, and a flange thickness of 25 mm (hereinafter represented as H9000 ⁇ B300 ⁇ 12/25), the second type being H850 ⁇ B300 ⁇ 12/25, and the third type being H800 ⁇ B300 ⁇ 12/25.
  • the UR mill was spaced by 3 m from the UE mill
  • the UF mill was spaced by 120 m from the UE mill.
  • the horizontal roll widths of the UR mill and the UF mill were 850 mm.
  • 7 (seven) passes in a tandem reversing action through the UR and UE mills and a final pass through the UF mill completed the H900 ⁇ B300 H-section steel.
  • rolling was accomplished with a space ( ⁇ ⁇ 50 mm) defined between the inside surfaces of the respective flanges of a blank piece being rolled and the horizontal rolls.
  • the horizontal roll widths of the UR and UF mills were set to 800 mm.
  • a total of 7 passes in a tandem reversing action through the UR and UE followed by a final pass through the UF converted the blank piece into an H850 ⁇ B300 H-section steel.
  • rolling in the UE mill was carried out with a space ( ⁇ ⁇ 25 mm) defined between the flanges' inside surfaces of the blank piece being rolled and the horizontal rolls.
  • the UR mill and the UF mill were set to have the same horizontal roll width of 750 mm. Subsequently, 7 (seven) passes in a tandem reversing action through the UR and UE mills and a final pass through the UF mill completed the H800 ⁇ B300 H-section steel. In the UE, rolling was accomplished with no space defined between the inside surfaces of the respective flanges of the blank piece and the horizontal rolls.
  • H900 ⁇ B300, H850 ⁇ B300, and H800 ⁇ B300 could be manufactured by only one UE mill.
  • Figure 12 is a table showing manufacturing tolerances of the hot-rolled H-section steels manufactured according to Examples 1 - 6 and those of welded H-section steels. As is apparent from the same figure, the H-section steels according to Example 1 have a dimensional accuracy which is well within the allowable manufacturing tolerances of the welded H-section steels.
  • a blank piece was given 6 passes through the UR, UE and UF mills in a reversing action, during that time the UF mill did not take part in the rolling action, while the UR and UE mills engaged in the rolling action to perform intermediate rolling to produce an intermediate blank piece of a shape suitable for the H900 ⁇ B300 product.
  • a 50 mm reduction in web height of the intermediate blank piece was attained in order to provide the same blank piece with a shape suitable for the production of the H850 ⁇ B300 product.
  • a final pass through the UF mill completed an H850 ⁇ B300 H-section steel.
  • the UF mill was equipped with horizontal rolls of the variable-width type which was variable in the width range of 750 to 850 mm.
  • the horizontal roll width of the UF mill was set to 850 mm, and after that, the blank piece was given 5 (five) passes through the UR, UE, and UF mills in a tandem reversing action. From the first to fourth passes, the UF mill did not take part in the rolling action, while the UR and UE mills engaged in the rolling action to perform intermediate rolling of the H900 ⁇ B300 product.
  • the UE mill attained a reduction in web height of the order of 50 mm, thereby producing an intermediate product having a shape suitable for the manufacturing of the H850 ⁇ B300 product. Accordingly, the horizontal roll width of the UF mill was changed to 800 mm, the intermediate product was subsequently rolled by the UF mill. By the finished rolling achieved in the UF, an H850 ⁇ B300 ⁇ 12/25 H-section steel was produced. As understood from Figure 12, the H-section steel had a dimensional accuracy which is superior to the dimensional accuracy of the H-section steel of Example 2.
  • a continuous cast slab having a thickness of 300 mm and a width of 700 mm was used as a blank piece.
  • Figure 14 is a view showing a pass schedule achieved to roll a roughly rolled blank section piece using a 2Hi breakdown mill (2Hi-BD mill).
  • 2Hi-BD mill having a groove arrangement shown in Figure 13
  • a beam blank (roughly rolled blank section piece for a desired H-section steel) having a web height of 720 mm, a web thickness of 60 mm, a flange width of 250 mm, and an average flange thickness of 110 mm was prepared according to the pass schedule shown in Figure 14.
  • the UE mill used in this Example had variable-width type horizontal rolls and, as shown in Figure 8, was equipped with vertical rolls having a central projection engaged with the outside surface of a corresponding flange.
  • the central projection had a width of 190 mm
  • a groove cut in each of the horizontal rolls had a depth d of 93.5 mm
  • the distance D between opposed sleeve rolls 19' was 0 (zero)
  • the horizontal roller with was 468 mm.
  • the distance D could be changed either on the on-line basis or on the off-line basis.
  • the distance between the opposed sleeve rolls was set to 50 mm with the result that the horizontal roll width L was increased to 518 mm.
  • the D and L were set to 100 mm and 568 mm, respectively.
  • the horizontal rolls of the UE mill were variable within a width range of 120 mm at maximum.
  • Figure 15 is a view showing a pass schedule achieved when rolling an H-section steel in the mill line shown in Figure 5(d).
  • the setting was made to determine a horizontal roll width of 468 mm for the UR mill, at that time the horizontal roll width of the UE mill was set to 468 mm, which was identical to the horizontal roll width of the UR mill. Accordingly, an H500 ⁇ B200 ⁇ 10/16 H-section steel was manufactured by executing the pass schedule shown in Figure 15.
  • the vertical rolls did not undertake a reduction of the flange portion in the direction of the thickness, and an opening identical to the thickness of the leading end (entry side) of the blank piece was maintained.
  • the vertical rolls had a primary function to protect the flange portions from becoming buckled when subjected to a force or pressure exerted from the horizontal rolls and to prevent the flange from becoming thick at the central portion thereof.
  • reduction of the flange and the web in the direction of the thickness was achieved in the UR mill at the ratio of 1.5:1.0 -2.0:1.0.
  • the horizontal roll width of the UR mill was set to 518 mm and the horizontal roll widths of the UE and UF mills were enlarged to 518 mm.
  • an H550 ⁇ B200 ⁇ 10/16 H-section steel was manufactured.
  • an H600 ⁇ B200 ⁇ 10/16 H-section steel was manufactured under the condition that the horizontal roll width of the UR mill was set to 568 mm, and the horizontal roll widths of the UE and UF mills were enlarged to 568 mm. Changes or variations in dimension of various parts of the obtained H-section steels are shown in Figure 12.
  • the H-section steels exhibited the dimensional accuracy comparable to that of the welded H-section steels, as shown in Figure 12.
  • the UR mill and the UE mill were equipped with the same horizontal rolls as those used in Example 5 described above, while the UF mill employed three horizontal rolls of different sizes used exclusively for the manufacturing of a corresponding one of the three types of H-section steels.
  • the UR mill, UE mill and UF mill were each set to have the same horizontal roll width of 568 mm. Accordingly, the UE mill and the UF mill did not take part in a reduction of the web height.
  • the horizontal roll width of the UE mill was reduced from 568 mm to 518 mm when a final pass was made through a mill group of UR and UE to roll the H600 ⁇ B200 product. Accordingly, the web height of the blank piece was reduced by 50 mm in the UE mill, followed by a finish rolling in the UF mill.
  • the horizontal roll width of the UE mill was reduced from 568 mm to 468 mm when a final pass was made through the UR mill and the UE mill to roll the H600 ⁇ B200 product.
  • the web height of the blank piece was reduced by 100 mm and after that a finished rolling was completed in the UF mill.
  • Dimensional changes or variations of various parts of the thus obtained H-section steels are also shown in Figure 12.
  • Figure 16 is a view showing an arrangement of rolls in a conventional 2Hi-E mill with a blank piece shown in cross section.
  • Figure 17 illustrates a pass schedule achieved, as a comparative example, to roll an H-section steel using the conventional 2Hi-E mill in place of the edger mill in the mill line shown in Figure 5(d).
  • a 2Hi-E mill having an edger groove of 93.5 pin in depth (d) shown in Figure 16 was installed in the mill line of Figure 5(d), and then the pass schedule shown in Figure 17 was executed to manufacture an H500 ⁇ B200 ⁇ 10/16 H-section steel.
  • an H600 ⁇ B200 ⁇ 10/16 H-section steel was also manufactured. Dimensional changes or variations of various parts of the thus obtained H-section steels are shown in Figure 12.
  • Figure 18 shows variations of the web offset taken in the rolling direction in conjunction with the H500 ⁇ B200 ⁇ 10/16 H-section steels obtained by Example 5 and Comparative Example.
  • the solid lines (K) represent the web offset observed when rolling is achieved by using the mill line shown in Figure 5(d) in which the UE mill and UF mill are each equipped with horizontal rolls having a variable width, and with the three universal mills installed close to one another.
  • the broken lines (M) represent the web offset observed when rolling is achieved when using the conventional 2Hi-E mill.
  • the bucking of the flange portions can be prevented by a reduction of the flange toes which is attained while the opposite surfaces of the flanges are confined by vertical rolls of the UE mill as shown in Figure 8.
  • the central portion of the flange is deformed first and then undergoes an extension in the rolling direction. Accordingly, the flange width at the leading and trailing ends of the blank piece can be equalized with the flange width at the central portion of the blank piece.
  • the dimensional accuracy can be increased to an extent incomparably higher than that of the method using a conventional 2Hi-E mill, and the web offset can be reduced considerably. Accordingly, the method of this invention is able to manufacture H-section steel having a high dimensional accuracy which is comparative to that of welded H-section steel. Further, since the web height can be changed during the rolling operation, a plurality of H-section steels having different sizes can be manufactured by using only one mill group and with a dimensional accuracy comparable to that of the welded H-section steel.
  • the H-section-steel manufacturing method of this invention is capable of improving the dimensional accuracy and reducing the web offset, as compared with rolling methods using the conventional 2H-E mill.
  • the web height can be readily reduced during the rolling operation with the result that by using only one mill group, H-section Steels of various different sizes can be hot-rolled with high dimensional accuracy comparable to that of the welded H-section steels.
  • the invention is applicable to the multi-size, small-quantity production of H-section steels used as steel frames in buildings.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Metal Rolling (AREA)
EP95902974A 1993-12-20 1994-12-16 Verfahren zur herstellung von h-stahlträgern Withdrawn EP0736341A4 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP319567/93 1993-12-20
JP31956793 1993-12-20
PCT/JP1994/002123 WO1995017269A1 (fr) 1993-12-20 1994-12-16 Procede de fabrication de poutres en acier en i

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EP0736341A1 true EP0736341A1 (de) 1996-10-09
EP0736341A4 EP0736341A4 (de) 1998-09-30

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EP (1) EP0736341A4 (de)
JP (1) JP2943326B2 (de)
KR (1) KR100254493B1 (de)
AU (1) AU681219B2 (de)
WO (1) WO1995017269A1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103862227A (zh) * 2012-12-10 2014-06-18 烟台新科钢结构有限公司 一种波纹腹板h型钢生产的工艺方法

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU693326B2 (en) * 1995-03-17 1998-06-25 Sumitomo Metal Industries Ltd. Method of and apparatus for hot rolling H-steel

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5550903A (en) * 1978-10-06 1980-04-14 Sumitomo Metal Ind Ltd Rolling method for wide flange beam
JPS5890301A (ja) * 1981-11-24 1983-05-30 Hitachi Zosen Corp 圧延方法
JPS61135404A (ja) * 1984-12-04 1986-06-23 Kawasaki Steel Corp Ｈ形鋼の熱間圧延方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5288565A (en) * 1976-01-21 1977-07-25 Nippon Steel Corp Method of rolling shape steel
JPS5564905A (en) * 1978-11-07 1980-05-16 Sumitomo Metal Ind Ltd Rolling method for wide flange beam using flat billet as blank
JPS6082201A (ja) * 1983-10-11 1985-05-10 Kawasaki Steel Corp Ｈ形鋼の熱間圧延方法
JPS61137601A (ja) * 1984-12-07 1986-06-25 Kawasaki Steel Corp Ｈ形鋼の熱間圧延方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5550903A (en) * 1978-10-06 1980-04-14 Sumitomo Metal Ind Ltd Rolling method for wide flange beam
JPS5890301A (ja) * 1981-11-24 1983-05-30 Hitachi Zosen Corp 圧延方法
JPS61135404A (ja) * 1984-12-04 1986-06-23 Kawasaki Steel Corp Ｈ形鋼の熱間圧延方法

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 004, no. 092 (M-018), 3 July 1980 -& JP 55 050903 A (SUMITOMO METAL IND LTD), 14 April 1980, *
PATENT ABSTRACTS OF JAPAN vol. 007, no. 189 (M-237), 18 August 1983 -& JP 58 090301 A (HITACHI ZOSEN KK), 30 May 1983, *
PATENT ABSTRACTS OF JAPAN vol. 010, no. 331 (M-533), 11 November 1986 -& JP 61 135404 A (KAWASAKI STEEL CORP), 23 June 1986, *
See also references of WO9517269A1 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103862227A (zh) * 2012-12-10 2014-06-18 烟台新科钢结构有限公司 一种波纹腹板h型钢生产的工艺方法

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Publication number Publication date
AU1200795A (en) 1995-07-10
JP2943326B2 (ja) 1999-08-30
AU681219B2 (en) 1997-08-21
EP0736341A4 (de) 1998-09-30
KR100254493B1 (ko) 2000-05-01
WO1995017269A1 (fr) 1995-06-29

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