JPS62156001A - Production of channel steel - Google Patents

Abstract

PURPOSE:To obtain a channel steel which has no surface flaws and has flange parts parallel with square corner angle parts even with an austenitic stainless steel by forming a billet, etc., into a semi-finished product having a linear sectional shape by hot caliber rolling then subjecting said product to cold forming. CONSTITUTION:The heated billet is rolled by using rolling rolls which are parallel with each other and a least one of which is driven by a driving device and is formed with the prescribed calibers; for example, an upper roll 8 and a driving roll 9 with the calibers 10. The semi-finished product 2 which have a pair of the linear flange parts 3 and web part 4, are approximately the same in the wall thickness at the above-mentioned two parts as the size of the product and is formed with approximately semi-circular projecting parts 6 at the points corresponding to the corner angle parts 5 connecting these two parts is obtd. The web part 4 and flange parts 3, 3 of the product 2 are then subjected to >=2 passes of cold forming by plural sets of cold forming rolls disposed in parallel with each other, for example, projecting and recessing rollers 13, 14 having pinch rollers 11, 12. The channel steel is thus obtd.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention combines hot hole rolling and cold forming to form billet or plate materials with perpendicular corner portions and parallel flange portions. The present invention relates to a method of manufacturing channel steel.

(Prior art) Channel steel can be easily manufactured by bending a slope, but channel steel formed by simply bending a plate has a web portion and a flange as shown in Fig. 7. There was a lack of thickness in the corners where the parts were connected, resulting in weak strength and low commercial value.

In addition, when producing channel steel by hot hole rolling, stainless steels, especially austenitic stainless steels such as SOS 304, have low deformability and high deformation resistance at high temperatures, resulting in seizure. Therefore, when the product is formed by hot hole rolling, there are drawbacks such as the occurrence of many surface defects on the product and premature wear of the rolling rolls, making it impossible to put it to practical use.

Therefore, when conventionally manufacturing channel steel using stainless steel such as SO3304, two angles are arranged in parallel in the longitudinal direction, although it is very inefficient for -at.
Butt welding is performed, and then the beads formed on the front and back sides are removed by cutting to produce channel steel.

(Problem to be solved) As described above, in the past, stainless steel channel steel has been manufactured by welding, although the productivity is poor and the cost is extremely high. In conjunction with the increasing demand for stainless steel channel steel as a building material and decorative material, there has been a strong demand for the development of an inexpensive manufacturing method for stainless steel channel steel.

(Means for Solving the Problems) The present invention was made in view of the above-mentioned drawbacks in conventional groove rolling and universal rolling. The material factors are that it is small, has high deformation resistance at high temperatures, and is easily prone to seizure, and there is a large difference in roll circumferential speed at the flange during rolling, which is likely to cause seizure at the flange. Taking forming factors into consideration, the present invention improves the manufacturing method of channel steel by making the wall thickness of the flange part and web part the same as the product dimensions by hole hot rolling, and making the cross section straight. , Sukuna (both are intermediate products in which an approximately semicircular protrusion with a radius of curvature of 1/2 or more of the plate thickness of the flange part is formed at a location corresponding to the corner part, and if necessary, the back side of the protrusion) The present invention is characterized in that the intermediate product is divided into two parts: a pair of web parts of the intermediate product using a curvature-forming roll, and a straight flange part formed into a flange part perpendicular to the web part.

The present invention involves forming an intermediate material having the above-mentioned cross section from a rolled material such as a billet by groove rolling.
Using rolling rolls that are arranged parallel to each other and at least one of which is rotated by a drive device, the flange part is made straight like the web part in order to reduce the difference in roll circumferential speed at the flange part.

Furthermore, the present invention provides cold rolling processing of a channel steel having flanges parallel to each other and a flat web section perpendicular to the flange portions from the intermediate product. Considering that it is difficult to obtain the desired amount of processing in one pass due to the characteristic of being significantly work hardened during processing, the number of passes using cold rolls arranged parallel to each other is set 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, and the flange part and the web part are perpendicular to each other. This prevents partial thickness changes in the intermediate product and defects in the product due to improper processing. It is something to do.

In addition, the reason why the flange part of the intermediate product is made straight with the web part in the hot hole rolling process 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 formation of an approximately semicircular protrusion with a radius of curvature of 1/2 or more of the plate thickness of the flange at a location corresponding to the corner where the flange and web of the intermediate product are connected is a result of cold processing. When molding, it is difficult to mold into right-angled corners because there is little meat overhanging! ! ＋This is because there is.

In addition, if it is less than this, insufficient thickness will occur when the flange part is processed perpendicularly to the web part during cold roll processing.
This is because good corner portions cannot be obtained.

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.

(Example) 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, and 2 is a plate in which a pair of flange portions 3 and a web portion 4 are linear, and the radius of curvature is that of the flange portion 3 at a location corresponding to a corner portion 5 where the flange portion 3 and the web portion 4 are connected. This is an intermediate product with a semicircular protrusion 0.8 times the thickness.

FIG. 2 shows 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). , 9 is a driving roller, and 10 is a hole type.

FIG. 3 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. , 12 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 S with a cross section of 50 squares and a length of 11,000 tons.
The OS 304 fillet was heated to 1050°C, and then the billet was transferred to a rolling roller using rollers (not shown).
The fillets 1 and 7 are processed one after another, and the flange 3 and web 4 are made to have the same wall thickness as the product dimensions without seizure occurring on the flange 3. The intermediate portion is linear and has a semicircular protrusion 6 with a radius of curvature 0.8 times the thickness of the flange portion 3 at a location corresponding to the corner portion 5 where the flange portion 3 and the web portion 4 are connected. Product 2 was manufactured.

Next, the intermediate product 2 formed in the above process is held between pinch rollers 11, and is inserted 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 flange portions 3 which are perpendicular to the web portion 4 and parallel to each other without causing a thickness change was manufactured.

(Effects of the Invention) As described above, the present invention produces an intermediate product with a straight cross section in hot hole rolling process, so that it has a low deformability like austenitic stainless steel and has a very high deformability. Even steel that is prone to seizure can be hot rolled without surface flaws, and even in cold rolling, the thickness of intermediate products can be changed by using a combination of convex rollers and concave rollers. It is possible to manufacture channel steel with right-angled corners and parallel flanges without giving rise to
It can be manufactured at a significantly lower cost than conventional angles welded into channel steel.

Furthermore, when producing channel steel using the groove rolling method using ordinary steel as a material, it is common to apply lateral pressure to the flange part in the finishing hole die to improve the overhang of the wall. This tends to cause galling at the flange, and in order to prevent this, the flange is usually rolled with a slight taper, and the flange of the channel steel manufactured by the above rolling method has a taper. remains as it is.

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 you can see, the method of the present invention is highly practical.

[Brief explanation of drawings]

Figures 1 to 6 show examples of the present invention. Figure 1 shows a cross section of an intermediate product, Figure 2 shows the final rolling roll shape, and Figure 3 shows a cold roll. FIG. 4 is a schematic diagram showing a roll and a pinch roller used in interroll processing, and FIG. 4 shows the shapes of a convex roller and a concave roller used in cold roll processing. FIG. 5 is a billet, FIG. 6 is a cross section of an intermediate product with protrusions formed on both sides, and FIG. 7 is a cross section of a channel steel formed by plate bending. 1: Billet, 2: Intermediate product, 3: Flange part 4: Web part, 5: Corner part, 6: Projection part 8: Upper roll, 9: Lower roll, 10: Hole mold 11.12: Pinch roller, 13 :Convex roller 14:Concave roller 111 Pi 79 4I 2 ■ Fig. 5

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, and the cross-sectional shape of the pair of flange parts and the web part is straight, and at least the part corresponding to the corner where the flange part and the web part connect is approximately semicircular. An intermediate product is formed into a shape with a protruding part, and the wall thickness of the flange part and the web part is almost the same as the product dimensions, and then the intermediate product is formed with multiple sets of cold forming rolls arranged parallel to each other. Accordingly, the web part and the pair of straight flange parts of the intermediate product are cold-formed in at least two or more passes to form a channel steel having a parallel flange part and a flat web part. Method of manufacturing steel.