JPS60250803A - Production of channel steel - Google Patents

Abstract

PURPOSE:To produce inexpensively a channel steel by forming a web part and a pair of flange parts which have the same shape and are connected to each other linearly via projecting parts from a billet and bending the flange parts perpendicularly to the web part. CONSTITUTION:The billet is rolled by calibers 10 of an upper roll 8 and a lower roll 9 to form an intermediate product 2 having the web part 4 and a pair of the flange parts 6 which have the same wall thickness as the size of a product and are connected linearly to each other by projecting parts 6 formed perpendicularly to the points corresponding to corner angle parts 5. Recesses 7 having the radius of curvature of >=2 times the thickness of the parts 3 are preliminarily formed on the rear side of the parts 6. The product 2 is then sandwiched by pinch rollers and the flange parts 3 are stepwise formed by a projecting type roller 13 and a recessed type roller 14 disposed above and below and are thereby made perpendicular to the web part 4 without changing the thickness, by which the channel steel having the flange parts 3 parallel with each other is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION In combination, the present invention relates to a method for producing channel steel with parallel flanges from billets or plates.

Generally, when manufacturing channel steel using ordinary steel as a material,
The channel steel was formed into the desired final shape by hot hole rolling. However, stainless steels, especially austenitic stainless steels such as 5US304, have poor deformability compared to the above-mentioned steels (and have large deformation resistance at high temperatures and are prone to seizure, so When formed by rolling, there are drawbacks such as a large number of surface defects on the product and premature wear of the rolling rolls, making it impossible to put it to practical use.Therefore, conventional SO5304
When manufacturing channel steel using stainless steel such as stainless steel, it is generally very inefficient to arrange two angles in parallel in the longitudinal direction, butt weld them, and then weld the beads formed on the front and back sides. It is removed by cutting to produce channel steel.

In this way, in the past, stainless steel channel steel was produced by welding, despite the poor productivity (and very high cost).In recent years, stainless steel channel steel has been used for construction In conjunction with the increasing demand for stainless steel as a material and decorative material, there was a strong demand for the development of an inexpensive manufacturing method for stainless channel steel.

The present invention was made in view of the above-mentioned shortcomings in conventional groove rolling and nuclear rolling, and the inventors discovered that austenitic stainless steel has poor deformability compared to other steel types.
In addition, there are material factors such as high deformation resistance at high temperatures and the tendency for seizure to occur easily, and forming factors such as the fact that there is a large difference in roll peripheral speed at the flange during rolling, making it easy for seizure to occur at the flange. Taking these factors into consideration, the present invention has developed a method for manufacturing channel steel by forming an intermediate product with a flange portion, a protrusion at right angles to the flange, and a recess on the back side of the protrusion through hole hot rolling, and cooling. It is in an open mold roll.

The present invention uses rolling rolls arranged parallel to each other and at least one of which is rotated by a drive device to form an intermediate material having the above-mentioned cross section from a rolled material such as a billet by groove rolling. In order to reduce the roll circumferential speed difference at the flange portion, the flange portion is made straight like the web portion. Furthermore, the present invention cold-rolls a channel steel having mutually parallel flange portions, a flange portion, and a right-angled flat web portion from the intermediate product, and the austenitic stainless steel as the workpiece material is cold-rolled. Considering that it is difficult to obtain the desired amount of processing in one pass due to the characteristic of being significantly work hardened by processing, the number of passes using cold rolls arranged parallel to each other is at least two passes, and the number of passes is set to be similar to that of the web. A linear flange part is formed in stages to make the flange part perpendicular to the web part, which prevents partial thickness changes in the intermediate product or defects in the product due to improper processing. It is something.

In addition, the reason why the flange part of the intermediate product is made straight with the web part in hot large-scale rolling is to reduce the difference in roll circumferential speed at the flange part during rolling and to prevent seizure from occurring at the flange part. It is.

Furthermore, the reason why we formed an almost right-angled protrusion at the corner where the flange and web of the intermediate product connect is because cold forming is difficult because there is little overhang of the flesh. Also, the reason why a concave part with a radius of curvature of more than twice the plate thickness of the flange part is formed on the back side of the protruding part is because the flange part is processed perpendicular to the web part during cold rolling. This is because sometimes work hardening occurs locally in the initial stage of molding, making it impossible to obtain good corner parts.

Furthermore, in cold rolling, pinch rollers are provided before and after the cold rolling as necessary. This improves the biting of intermediate products and prevents the forming roller from slipping.

The present invention will be explained below based on one embodiment thereof.

The present invention initially forms an intermediate product from a billet using a plurality of rolling roller sets having a predetermined groove shape, which are arranged parallel to each other and at least one of which is rotated by a drive device. 1 is a billet, 2 is a pair of flange portions 3 and a web portion 4 that are linear, and has a protrusion portion 6 that is perpendicular to a portion corresponding to a corner portion 5 where the flange portion 3 and the web portion 4 are connected; This is an intermediate product in which a recess 7 is formed on the back side of the part 6.

FIG. 1 shows the final rolling rolls for forming the intermediate product 2, which are arranged parallel to each other and have a predetermined hole shape whose lower part is rotated by a drive device (not shown), and 8 is an upper roll. 9 is a driving roller, and lO is a hole type.

FIG. 2 is a schematic diagram showing a plurality of sets of forming rollers arranged parallel to each other and having a desired roll shape, which are used to cold roll the intermediate product 2, and 11 is a pinch roller on the entry side. , 2 is a pinch roller on the exit side, 13 is a convex roller provided on the upper side, and 14 is a concave roller provided on the lower side.

First, a billet I having a cross section of 50i'' and a length of 1000mm is heated to 1050°C, and then the billet 1 is transferred to a rolling roller by a roller (not shown), and the billet I is heated to 1050°C.
The flange portion 3 and web portion 4 have the same thickness as the product dimensions without seizure occurring in the flange portion 3, and the pair of flange portion 3 and web portion 4 are straight. In addition, a right-angled protrusion 6 is formed at a location corresponding to the corner 5 where the flange part 3 and the web part 4 are connected, and the radius of curvature is 2 times the plate thickness of the flange part 3 on the back side of the protrusion 6.
An intermediate product 2 was produced in which a recess 7 more than double the size was formed.

Next, the intermediate product 2 formed in the above process is held between pinch rollers 11 and squeezed between convex rollers 13 and concave rollers 14 disposed at the top and bottom to form the flange portion 3 in stages. A channel steel having flanges 3 which are perpendicular to the web part 4 and parallel to each other was manufactured without any thickness change.

As mentioned above, the present invention manufactures an intermediate product with a straight cross section through hot hole rolling, thereby preventing the product from having poor deformability like austenitic stainless steel and causing seizure to occur infrequently. Even soft steel can be hot rolled without surface flaws, and even in cold rolling, by using a combination of convex and concave rollers, the intermediate product can be rolled in parallel without changing its thickness. It is possible to manufacture a channel steel having a flange portion, and it can be manufactured at a significantly lower cost than the conventional channel steel made by welding angles.

Furthermore, when producing channel steel using the groove rolling method using ordinary steel as a raw material, it is common to apply lateral pressure to the flange part in order to improve the overhang of the material in the finishing hole die. Galling tends to occur in the flange, and to prevent this, the flange is usually rolled with a slight taper, and the taper remains in the flange of channel steel manufactured by the above rolling method. It is something. On the other hand, in the method of the present invention, the flange part is in a straight line with the web part, so there is no fear of galling on the flange part, and there is no need to attach a taper to the flange part as in the conventional method. As described above, the method of the present invention has high practicality.

[Brief explanation of the drawing]

Figure 1 shows the final rolling roll shape, Figure 2 is a schematic diagram showing the rolls and pinch rollers used in cold rolling, and Figure 3 shows the convex and concave rollers used in cold rolling. This figure shows the shape of the roller. Na L! Figure 1;
Filletsum complete゛, F, tlfllJ middle/'Q provisional #bite I! 7er＼Bimenode"δro. 1: Billet 2: Intermediate product 3: Flange part 4: Web part 5: Corner part 6: Projection part 7: Recessed part 8: Upper roll 9: Lower roll 10: Hole mold 11. 12: Vinci roller 13: Convex roller 14: Concave roller!4 83 Figure

Claims (1)

[Claims] In the production of a channel steel formed by a flange part and a web part, the steel is heated to a predetermined temperature by rolling rolls having a predetermined groove, which are arranged parallel to each other and at least one of which is rotated by a drive device. The rolled material is rolled, so that the pair of flange parts and the web part are linear, and a protrusion part that is approximately perpendicular is formed at a location corresponding to the corner part where the flange part and the web part are connected, and a protrusion part is further formed. An intermediate product is formed in which the radius of curvature is more than twice the plate thickness of the flange part on the back side of the part, and the wall thickness of the flange part and the web part is almost the same as the product dimensions. Using a plurality of sets of cold-open forming rolls arranged in parallel, the web part and the pair of straight flange parts of the intermediate product are cold-formed for at least two passes or more to form a parallel flange part and a flat web part. 1. A method for producing a channel steel, the method comprising: forming a channel steel having the following characteristics.