JPS59193702A - Method for rolling steel shape having hole in its web - Google Patents

Abstract

PURPOSE:To manufacture easily and economically a titled steel shape maintaining an accurate shape and having a large cross section by warm and hot shaping a steel shape through a process wherein a slitting mill is provided in addition to a universal mill system and a two-high mill system. CONSTITUTION:A hot billet 1 is formed into a prescribed shape by roughing mills A, B and is formed successively by a universal intermediate finishing mill C into an intermediately finished H-shape, then its flange height is controlled in a prescribed shape by a two-high mill D. The shapes of flange and web are formed into prescribed shapes by passing the material several times through the mills C and D, and after forming them into more accurate dimensions by a universal intermediate finishing mill E, slit marks 4 of proper pattern are provided at a proper distance to the web by a slitting mill F. Finally, the web width is spread by a finishing universal mill G to enlarge the slits for forming holes 26.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for rolling a section steel having holes in the web, and more particularly to a warm and hot rolling method for such a section steel.

Conventionally, steel sections with holes in the web have been manufactured from simple channel steel sections formed by bending p-plates by cold forming.

This steel section is made by cold channel forming using a two-high rolling mill system, followed by slits and widening rolling.Due to the cold rolling, the deformation resistance of the material is extremely high, so the shape of the surface is exaggerated. In addition, the strain caused by bending concentrates in the corners and causes work hardening, and the load characteristics as a section steel are poor, and it is easy to break, making it difficult to use as a section steel for large-shake structures. There was a limit.

The present invention has been made in view of these circumstances.

The gist of this is that steel billet material is rough rolled, intermediate finish rolling consisting of a two-high rolling mill thread and a universal rolling mill system, and finished If rolling is continuously rolled to produce a section steel. During warm or hot VC forming, a slit rolling process is inserted as a pre-process to finishing rolling to pre-apply slit marks at appropriate intervals and patterns on the web of the forming material, and also to form slit marks in the next process. There is a method VC for rolling a section steel having holes in the web, which is characterized by widening the web portion in finish rolling.

Next, the method of the present invention will be explained in detail with reference to the drawings.

FIG. 1 shows the process steps of the present invention method for rolling an H-beam steel with holes in the web portion in a warm or hot manner using a two-high rolling mill yarn and a uniform rolling mill system following rough rolling. It is something that The heated billet material l is sent to the rough rolling mill group (to) (B)
It is shaped into a predetermined shape by Ic, and then shaped into an H-section steel shape that is intermediately finished by a universal intermediate finishing mill (C), and the flange height is controlled to a predetermined shape by first and second rolling (mO). These rolling mills (C)
The 7 langes and the web are shaped into a predetermined shape by the universal intermediate finishing mill (color), and then finished into more accurate dimensions by the slitting mill F). The slit marks are applied in the pattern and finally the finishing universal rolling mill (Gl
While the width of the web is widened, the slits are enlarged to form holes, thereby forming a predetermined perforated web shape steel.

FIG. 2 μ is a schematic diagram illustrating the process of FIG. 1 in more detail. FIGS. 2(A) and 2(B) show an example of the groove shape 9.10 formed by the upper and lower rolls 8a+db used in the rough rolling mill. Slab material lij: Hole type 9
Passed ゜10 in several nogs, and then vertical roll l la
*Universal intermediate finishing mill (C) consisting of 11b, horizontal rolls 12g and 12b [shaped into the shape of the drilled hole m13]. Next, a two-stage rolling mill 0 having a hole 15 formed by the upper and lower rolls 1c 14a and 14b controls the height of the flange at the same time as thinning and widening the web.
Furthermore, a vertical roll 17a.

With a universal rolling mill having horizontal rolls 17b and 16a and 16bk, the thickness is further reduced as shown by the hole pattern 18, and the material is shaped into a substantially predetermined finish. Next, as shown in the groove 20, slit marks are made at appropriate intervals and patterns using a slit rolling machine α in which projections 21 are attached to the upper and lower rolls l9a, 191>.
) Obtain 2 slit marks with a pattern as shown in (). The spacing and pattern of the slit marks can be freely changed by VC by appropriately considering the protrusion shapes and positions of the upper and lower rolls 19a, 19b of the slitting mill (2).

The slitted section steel is finally rolled into vertical rolls 22a, 22.
The flange portion 25 is expanded and rolled while a tensile force is applied to the flange portion 25 by vertical rolls 22a and 22biC of a finishing universal rolling mill (G) having horizontal rolls 23a and 23bk. As a result of this, the slit mark enlarges and the hole 26
9. It is possible to obtain a section steel with a complete web.

In this case, in the present invention, warm means 200°C to 700°C.
℃ and hot generally refer to the temperature range from 7 U tj C to 1250 ℃, and the reason why all of these warm and hot processes are adopted is that warm rolling improves dimensional accuracy and toughness, and This is because the purpose of inter-rolling is to create a large cross-section by reducing deformation resistance.

Note that the relationship β>1.03α is satisfied between the web widths of the universal rolling mills [F]) and G) in FIG.

In addition, in the forming process G), it is desirable to reduce the web so that the thickness reduction rate is 3 inches or more, so that the wall thickness becomes uniform, but if uniform thickness is essential for the performance of the product, it is not necessary to reduce the web. . The forming process shown in FIG. 2 can be easily applied to forming channels, sheet piles, and section steel.

In addition, FIG. 3 shows an example of the shape of the H-section steel in the process of forming by the steps shown in FIGS. 1 and 2, respectively, and FIG. An example of the shape of the shaped material 2 that has passed through the groove of the universal intermediate finishing rolling mill in Fig. 2, and Fig. 3(b) shows the slit mark 4 that has passed through the groove of the slit rolling mill (■) in Figs. 1 and 2. FIG. 3(c) shows an example of the shape of a shaped material 3 having holes 2 in the web portion that has passed through the groove of the finishing universal rolling mill G) in FIGS. 1 and 2.
This is an example of an H-beam 5 having a diameter of 6. Note that 25 is a flange portion.

As explained in detail above, by hot working or warm working the shape G4T with holes in the web using a process in which a slit rolling mill is added to a universal rolling mill system and a two-high rolling mill system, the corner In addition, it is possible to easily and economically manufacture a large cross-section steel section with holes and a web width of up to 1,000 mm, which has not been possible in the past.

The results of the present invention will be illustrated in more detail with reference to Examples below.

Using the present invention, a section steel was manufactured using the rolling mill system shown in FIG. 1 having the groove type shown in FIG. 2. 250 as material
mX 250w1 Using 8M50 billet as steel type, web width 286w17 lunge width 121 by 11 passes
w11 Web thickness 4.4m, 30w x 9 in 1 workpiece
An H-beam steel as shown in Fig. 3(c) with a hole of m height was manufactured. That is, in Fig. 2, 250 w x 2
The 50 ms square billet) 1 was heated to 1200°C, passed twice through the hole in the two-high rolling mill [F]), and roughly shaped into an H-beam steel by the universal rolling mill in C). ), the width was widened and the height of the 7-lunge was controlled by the two-high rolling mill E), and after passing through the shaping process twice by the UniPurple rolling mill E), the web width was 238 mm and the flange width was 120.8 m.
It was finished into a rough H-beam steel with a web thickness of 4.8 mm.

After that, a slit mark with a slit width of 30 strips was made on the center line of the silanib and on the line of 1/2 of the web height using a two-high rolling mill for forming side slit marks, and then finished using a universal rolling mill (G). A good finish was done. At this time, the width was selected to be α = 238 m and β - 286 m, and the rolling reduction ratio of the web was 8%. The finishing temperature at the web portion was 600°C.

The thus obtained H-section steel has significantly less cracking in the web holes than a lightweight section steel with the same section modulus that has been cold-rolled, so it has extremely high resistance to fracture.
7. The strain value generated at the tip of the flange is the same 0.05%.
According to the results of repeated bending tests, the shape steel obtained by the manufacturing method of the present invention did not break even after 50,000 bends, compared to the lightweight shape steel manufactured by the conventional method which broke after 10,000 bends. It did not occur.

As is clear from the above examples, the present invention makes it possible to accurately maintain the shape of a section steel with arbitrary holes in the web while rolling it into a thin wall, and the industrial effect is extremely significant. There is something.

[Brief explanation of the drawing]

Figures 1 and 2 are schematic diagrams showing the process of producing an H-section steel with holes in the rainbow web according to the method of the present invention, and Figure 3 is an H-section steel processed by the process shown in Figures 1 and 2. FIG. 3 is a perspective view showing an example of the shape in the middle of modeling. (A) (B)... Rough rolling mill: (C) (G)... Universal intermediate finishing mill; (D)... Two-high rolling mill;
v)... Slit rolling mill; 0)... Finishing universal rolling mill; l... Billet material; 2゜3... Shaping material; 4
...Slit mark; 5...H-shaped steel with hole t: 8
a e 8 b...Upper and lower rolls of rough rolling mill: 9゜i
o--Roughing mill hole type; 1lat flb, 17. a
*17b, 22a, 22b... Vertical rolls of universal rolling mill; 1.2 a, l 2 b + l 6
a + l 6 b +23a, 23b...Horizontal rolls of the universal rolling mill; 13.18...Group shape of the universal rolling mill; 14a, 14b...Upper and lower rolls of the two-high rolling mill; 15...2 Hole type of corrugated rolling mill: 19a+
19b... Upper and lower rolls of the slit rolling machine; 20... Hole shape of the slit rolling machine; 21... Roll protrusion of the slit rolling machine; 25... Flange portion; 26... Hole. Agent: Patent attorney Masaaki Akizawa, Mitsugai (2 people)

Claims (1)

[Claims] (1) Rough rolling of the billet material, and intermediate finishing rolling consisting of a two-high rolling mill system and a universal rolling mill system. When forming a shaped steel section in warm or hot conditions by continuous finishing rolling, a slit rolling process is inserted as a pre-process to finishing rolling to form slit marks at appropriate intervals and patterns on the web of the forming material. 1. A method of rolling a section steel having holes in the web, characterized in that the web portion is provided with a hole in advance and the width of the web portion is fully widened in the next step of finish rolling.