JPS63101005A - Preupsetting method for welded h-shape steel - Google Patents

Abstract

PURPOSE:To prevent generation of buckling to be generated by the defective cut face of a slit material at the time of upset rolling by cleaving the end faces at both side edges of a web material with caliber rolls of a rolling mill and force-expanding the cleavage to form joint parts. CONSTITUTION:While the material is restrained by caliber side walls by the center of the material end faces flattened in a 1st stand, the end faces of the material are successively cloven at the center by the knifing webs of a 2nd stand. Since the material is transversely restrained, the end faces can be cloven with substantially no transverse expansion simply by notching said ends. The roll calibers 3 of a 3rd stand has the caliber width measurably larger than the thickness of the web material and decrease the depth by force-expanding the cleavage on the side faces of the web material while preventing the inclination of the web material with the sharp pointed knifing webs at the center. The cleavage on the side faces of the material is further force-expanded in a 4th stand. Since there is no restraint on the side faces, the thickness at the end parts increases largely. The buckling at the time of rolling down which occurs in the ruggedness of the cut face of the web is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a method for upsetting both side edges of a web material in a production line for welded H-section steel.

(B) Prior Art As shown in FIG. 2, a conventional welded H-section steel is manufactured by successively summer-tool welding three pieces of slit material of a hot-rolled coil. In this case, the thickness of the web material W is 2.3 to 3
．． It is about 2n. This web material is subjected to pre-upset rolling of about 2 RM in the width direction in a continuous rolling mill 1 consisting of four units to increase the thickness of the end portion by 0.5 to 1 inch to make it easier to weld.

As shown in FIG. 3, flat rolls No. 1 to No. 4 are used for rolling down. Therefore, if the cut surface of the slit material (web material) is not flat, it will not be possible to roll it down uniformly, resulting in material buckling during pre-upset rolling. When material buckling occurs, welding defects are likely to occur.Also, even if the amount of reduction is increased in order to increase the thickness of the end portion, the amount of increase will not be very large because it is cold rolling.

(c) Problems to be Solved by the Invention The problems to be solved by the present invention are to prevent buckling that occurs during pre-upset rolling due to poor cut surfaces of the slit material, and to prevent buckling between the web material and the flange material. The objective is to obtain a pre-upset method suitable for joining.

(d) Means for Solving Problems The pre-upsetting method for welded H-section steel of the present invention is a method for pre-upsetting the welded H-section steel on both sides of the web material using a continuous rolling mill in the production line of welded H-section steel. Then, by making cracks on both side edge surfaces of the web material with grooved rolls of the rolling mill, and spreading out the cracks to form a joint,
The above problems have been resolved.

(e) Examples Examples of the method of the present invention will be described with reference to the drawings.

A web material having a width of 100 to 200 cm and a thickness of 2.3 to 3 Ozz was placed vertically with the width direction facing up and down, and the grooved roll No. 1.2 of the continuous rolling mill 1 was used. Reduce the width by 3°4. In this case, the number of stands is four.

The roll hole type No. 1 of the first stand is a box hole type having a hole width slightly smaller than the thickness of the web material. Since the web material has box hole type side walls restraining both edges of the web material, it is difficult for the web material to collapse or buckle.
By rolling down the web material by approximately III in this state, the unevenness on the cut surface of the web material can be flattened without causing buckling. In this case, since both side edges of the web material are restrained, the width expansion (thickness increase) at the end portions is small.

The roll hole pattern of the second stand has a hole width approximately the same as the box hole pattern of the first stand, and has a sharp knife web with an apex angle of 60° in the center of the hole pattern. First, while restraining the material with the hole-shaped side wall at the center of the flattened material end face with the first stand, a knife web is used to cut the material in the center.
Since the width of the material is restricted by the hole mold, there is almost no width expansion, and only a notch with a depth of about 1 am is inserted.

Roll hole type No. 3 of the third stand has a considerably wider hole width compared to the thickness of the web material and has an apex angle of 60" at the center.
It has a blunt knife web.

While preventing the web material from collapsing with this blunt knife web, the depth of the web material is made shallow from 1 inch to 0.6 zm by spreading out the sides of the web material.

At this time, since there is no side restraint, the thickness of the end portion increases greatly.

Finally, the roll hole type No. 4 of the fourth stand has a hole width nearly twice as thick as the thickness of the web material. This box hole type further expands the material side surface and makes the depth from 0.6 zm to about 0.31111 mm.

Also in this case, since there is no side restraint, the thickness increase at the end is large.

The case of manufacturing H2O0xlOOx3.2/4.5 will be explained with reference to FIGS. 1 and 4. The web material used is a slit material with a thickness of 3.2 cm and a width of 198 iv. The number of stands of the continuous rolling mill used is four. In the first hole type No. 1, the pressure is reduced by 1a+i+.

In this case, the hole shape of No. 1 has a hole bottom width of 3. It is an Oav box hole type. As a result, the unevenness of the cut surface, which was about 0.5zz, becomes almost flat.

Next, hole type No. has a knife web with an apex angle of 60°, a tip corner R of 0.21 m, and a depth of 1.2zz.
, 2, reduce the thickness by about 2JIM, and insert a slit with a depth of about 1zz into the center of the thickness of the side edge surface of the web material. At this time, the material width hardly changes.Since the material is restrained by the side surface of the hole in both hole types No. 1+No. 2, the thickness increase at the end is the same for hole types No. 1 and 1. No. 2, the total is about 0.4 am.

Hole type No. 3 has an apex angle of 60° and a tip corner R0, 8.
III, it has a blunt knife web with a depth of 0.6xm, and the hole width is 4.5xx, which is considerably wider than the material width.

Using this hole type No. 3, the material is reduced by about 1 u and the material is spread out. As a result, the end thickness of the material is 0.
．． Spreads about 8jv. The depth at this time is 1i+m
It becomes shallower from 0.6 mm.

Finally, hole type No. 4 is a very wide box hole type with a hole bottom width of 5 mi+. Using this, add the material to 11 more
11 Press down. In other words, hole type No. 1 to hole type No. 4.
By performing the reduction of 3 sv, the end thickness increased by about 0.8 zz, resulting in a total increase of 2 x m.

Even with this, the depth of the material remains about 0.3xw. However, if the recess depth is 0.6 mx or less, welding defects will not occur, so about 0.3zz is not a problem.

(f) Effects According to the method of the present invention, it is possible to eliminate buckling during rolling due to unevenness of the cut surface of the web material, and it is also possible to eliminate buckling during rolling due to the unevenness of the cut surface of the web material, and at the same rolling volume, it is nearly twice that of conventional flat roll rolling. An increase in thickness at the edges is obtained.

[Brief explanation of the drawing]

FIG. 1 is a detailed explanatory diagram of the present invention. Figure 2 shows conventional welding H
Pre-ups on a section steel production line. Fig. 3 is an explanatory diagram of the conventional pre-upset type process, Fig. 4 is an explanatory diagram of the pre-upset forming process by the method of the present invention, and Fig. 5 is an illustration of the reduction I and width expansion. A graph showing relationships. 1: Continuous rolling mill W: Web material patent applicant Sumitomo Metal Industries, Ltd. (5 others)

Claims (1)

[Claims] In a production line for welded H-beam steel, when pre-upsetting is performed on both side edges of a web material using a continuous rolling machine, the grooved rolls of the rolling machine are used to make cracks in the end faces of both side edges of the web material, and then A pre-upsetting method for welded H-section steel, which is characterized by forming a joint by pushing it apart.