JPS6043553A - Hot rolled beam and its production - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

U.S. Pat. No. 4,251,973, which relates to a load beam structure invented by the present inventor, discloses a welded web with a corrugated central portion and uncorrugated strips directly adjacent to the flanges on both sides. ■The configuration of the beam is described. The beam odor provides high load strength without increasing the weight of the beam or using relatively expensive materials. The beams described in the above specification have excellent strength and, because of the process of welding the flange to the web, reduce manufacturing costs compared to, for example, hot rolling. The hot-rolled beam, which is a modification of the above-mentioned I-beam, uses a billet with a nearly rectangular cross section, which is sufficiently heated, and then both sides of the billet are sandwiched between forming rolls and formed into the desired engineering shape. can be obtained. According to this method, the flange and web are formed substantially simultaneously. Similarly, if the load beam is to be formed into a generally C-shaped cross-section, the forming rolls are applied to only one side;
The other side is fixed and the kneading forms upright arms along the edges of the billet to act as flanges for the cross-beam web. present invention

In the first stage of manufacturing a beam (or C-beam), a heated billet is formed by rolls into a pair of edge flanges. The web extending along the centerline of the flange has a tapered cross-sectional shape such that the web has a maximum thickness where it contacts the flange and a minimum thickness approximately midway between the flanges. There is. The web is substantially uniform and continuous from the greatest thickness to the least thickness in the middle. In a second stage, a beam with a tapered flat web is introduced between a pair of forming rolls to form a set of corrugations extending perpendicular to the length of the beam l; In addition, the portion directly adjacent to both flanges is left as a portion without corrugations. The present invention will be described in detail below with reference to the drawings. In FIG. 6 and FIG. 4, an example of a load beam created by the manufacturing method described later is indicated by the reference numeral 10.
It includes a pair of rectangular flanges 11 and 12 separated by a web 13 so as to have a single-shaped cross-section. The flanges 11 and 12 have a normal configuration formed by a hot rolling process, and are tapered so that the thickness near the web 13 is thicker than the edge. A radius 14 is attached to the portions 11 and 12 that connect with the web 13. Fig. 1a shows the first step in creating a load beam by the method of the present invention, and the beam jO is The thickness of the web is the maximum thickness f) in the area adjacent to the flange.
fe, and a substantially uniform taper is continuously applied so that the minimum thickness d is obtained at the center. It is preferable to set the thickness d to about half the thickness D, thereby obtaining an ideal weight/strength ratio as described later. In a second step, the web is formed with its central portion, a portion 15 which projects outwardly from the flat plane. These outwardly projecting portions 15 are preferably formed so as to project alternately on both sides from a flat plane. As shown in FIGS. 6 and 4, the outwardly projecting portion 15 of the web 3 is preferably formed as a plurality of corrugations in which the metal plate is First it is bent in one direction [90° from a flat plane, then the immediately adjacent part is bent 90° in the opposite direction from a flat plane.
Preferably, it is bent. In addition, the corrugated portion is rounded where the bending direction changes, as shown in Figure 5, to avoid the formation of sharp corners or sharp bends that may reduce the beam intensity. It is preferable that the The portions directly adjacent to the flanges 11 and 12 above and below the corrugated portion are flat surface strip portions 6 and 17 where the corrugated portion is frequently present. This combination of flat strips and longitudinal corrugations in the central part not only increases the load strength compared to a beam of the same dimensions with an entirely flat web. , it is possible to maintain high resistance to bending stress. Regarding the dimensions of each part to achieve the effects of the present invention,
In FIG. 6, the width X2 of the non-wavy band portions 16 and 17 becomes a problem. In particular, it is preferred that the minimum value of X2 is at least twice the maximum thickness D of the web. Otherwise, the beam formed will have poor bending strength due to the so-called "accordion effect". FIG. 2IC shows J pairs of forming rolls 18 and 19 designed to form band-like corrugations 15 along their webs in the first stage beam shown in FIG. 1a. ing. Forming rolls 18 and J9 have receptacle grooves 20 for receiving and holding the beam flanges during corrugation.
~23. If the web is not very thick, the corrugation is done 'cold', but if the web is thicker, the first stage beam is heated to a 'hot' temperature and the corrugation is done 'hot'.
It will be held in When a C-beam is desired, its structure is as described above.
Very similar to a beam. In the j-th stage of the process, the hot rolled C
Beam 24 has a web substantially similar to beam 10 shown in FIG. 1a. Then, depending on the thickness of the web, the roll 1 shown in FIG.
8 and ]9 are used to form the wavy portion. The final C-beam is shown in FIG. 6, and has similar size ratios to the ■-beam shown in FIG. Another configuration of I-beam 25 is shown in FIG. The first stage of the beam in this case is the same as the hot rolled beam with tapered web shown in FIG. 1a. In a second step, the forming rolls are modified so that the corrugations 26 project only on one side of the web, as shown in FIGS. 7 and 9. Similarly, FIG. 8 shows a C-beam configured such that the corrugations 27 project outwardly from, for example, only one major surface of the web. This structure is obtained in exactly the same manner as the beam 25 shown in Fig. 7, except that the flange is formed into a C-shape instead of a 1-shape in the first stage hot rolling process. . According to the load beam manufacturing method according to the present invention as described above, the overall beam weight can be significantly reduced without compromising the load strength. That is, tapering the web reduces weight 7 and corrugating increases the load carrying capacity of the beam, resulting in increased overall beam strength and 7 weight reduction. Furthermore, since there is no need for welding, manufacturing costs can be significantly reduced. The most common material for the beams mentioned above is steel, but the beams can be made of aluminum or plastic to achieve similar results.

[Brief explanation of the drawing]

Figures 1a and 1b are cross-sectional views of the hot-rolled beam obtained by the j-th stage of the pool process for forming E-beams and C-beams, respectively, and Figure 2 is a cross-sectional view of the forming rolls for the second stage of the process. 6 is a front view of a beam formed by the method of the present invention, FIG. 4 is a sectional view taken along line 4-4 in FIG. 6, and FIG. 5 is a sectional view taken along line 5-- in FIG. 3. 6 is a cross-sectional view of a C-beam formed by the method of the present invention, FIG. 7 is a cross-sectional view showing deformation of the ■ beam according to the present invention, and FIG. 8 is a cross-sectional view of a C-beam according to the present invention. FIG. 9 is a cross-sectional view taken along line 9--9 in FIG. 7. In the figure, 10 is a beam, 11 and 12 are flanges, 1
3 is a web, 5 is a corrugated portion, and 18 and 19 are rolls, respectively.

Claims (1)

Claims: 1. A hot-rolled beam having a pair of flanges connected to each other by a web, wherein the web is thickest at a portion directly adjacent to the flanges and the web comprises a plurality of first portions projecting outwardly from one side of the plate; and a plurality of first portions projecting outwardly from one side of the plate; a plurality of second portions protruding outward from the other side; and two band-shaped portions directly adjacent to each of the flanges and in which the first and second portions do not exist. rolled beam. 2. The beam according to claim 1, wherein the web has a maximum thickness approximately twice as thick as a minimum thickness. 3. The beam according to claim 1, wherein the first and second portions of the web are comprised of wave-shaped portions extending in a direction perpendicular to the flange and continuously connected to each other. Said beam. 4. The beam according to claim 1, wherein the portion of the web with the smallest thickness is located at the center between the pair of flanges. 5.% The beam according to claim 1, wherein the pair of flanges protrudes outward from both sides of the web to form a beam. 6. The beam according to claim 1, wherein the pair of flanges protrudes outward from one side of the web to form a C-beam. 7. A beam according to claim 1, characterized in that the width of each strip is at least equal to the distance between the first and second portions projecting outwardly from the plate of the web. said beam. 8. A first step in which the billet is hot rolled to include a pair of flanges separated by a web and the thickness of the web is greatest adjacent the flanges and least intermediate between the flanges. forming a beam of the hot-rolled first stage beam with a portion projecting outwardly from the web, and forming a portion directly adjacent the flange of the projecting portion; 1. A method for manufacturing a beam having a pair of flanges and a plate-like web, the method comprising: leaving the beam as a non-existing band-like portion. 9. The method of claim 8, wherein the step of forming an outwardly projecting portion in the web comprises
A method as described above, characterized in that it is carried out by sandwiching the staged beam between forming rollers while maintaining it at a temperature substantially below the temperature at which it becomes malleable. 10. The method of claim 8, wherein the step of forming outwardly projecting portions in the web comprises a preliminary step of heating the first stage beam to a temperature at which it becomes malleable. The method characterized in that it comprises: 11. The method according to claim 8, wherein a certain portion projects outward from one side of the web, and a certain portion projects outward from the other side of the web. Said method.