JPH0335001B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a deformed section steel having a J-shaped cross section, and particularly to a method for producing a J-section steel by hot rolling and then cold cutting the J-section steel. The present invention relates to a method for manufacturing the resulting J-shaped rib material.

With the recent development of shield construction methods in tunnel construction, steel segments that can withstand earth pressure, water pressure, and ground surface loads are commonly used, but there is a growing demand for improved strength of the segments themselves.

As is well known, vertical rib members are arranged on steel segments to receive the reaction force of the jack for shield propulsion, and also play the role of transmitting the load as a ring and preventing buckling. There was a demand for thick vertical rib material.

By the way, vertical rib members have conventionally been manufactured by press molding, but the following problems are inherent.

That is, as shown in Fig. 1, a steel plate or flat steel cut into a width W ₁ and a thickness t ₁ is pressed against a lower die with a force of P by an upper die having a radius of R in a press machine, and is bent at an angle of 90°.
J with the required flange length on the left and right sides.
molded into a shape. At this time, the area around the R portion becomes thinner in the width direction at the same time as the deformation, creating a difference in thickness from the flange.

That is, as shown in FIG. 2, t ₂ <t ₁ and the total length of the processed flange W ₂ is longer than the width of the plate before processing, so W ₂ >W ₁ . For this purpose, materials that require bending are required to be soft and stretchable with good bending performance. In addition, in the case of 90° bending, since the R of the entire upper die is as small as _1.5t1 , cracks are likely to occur at the end of the plate where the plate stretches when bent. For this reason, when cutting out a member from a steel plate, first, the length of the required processed member is determined to be the slitting width, and the steel plate is cut and divided in the length direction with a frame planer.

Thereafter, since gas cutting causes bending due to heat, the workpiece is cut to the width with a shear to produce a member of predetermined dimensions. The purpose of this is to suppress the occurrence of cracks during bending, and the steel plate is bent in a direction perpendicular to the rolled length direction of the steel plate.

Also, when cutting and collecting parts from flat steel, it is necessary to bend the flat steel around the rolled direction.
Cracks are likely to occur. For this reason, it is necessary to apply heat to the ends before bending to prevent the occurrence of cracks, and a process is added to keep the cracks small even if they occur.

Also, flat steel is cut to a predetermined length with a shear,
As shown in FIGS. 3a and 3b, when the board is cut with a shear, small burrs occur in opposite directions on the upper and lower surfaces of both ends of the board. When this plate material is bent at 90° with a small R around the length direction, when the surface with the burr 13 is on the lower mold side as shown in c, the R part on the outside of the plate will stretch. Cracks 14 are likely to occur from this burred portion.

The present invention solves the above-mentioned problems, and the gist of the present invention is to form a forming hole in which the right and left intersections of the flanges have an R-shape when manufacturing a shaped steel having flanges by hot rolling. The rolling is started to gradually approximate the R-shaped shape to the product shape, and a guide roller having left and right vertical guide rolls between the final groove roll and the forming groove roll one pass before the final groove roll. In the machine, the material to be processed is given an intermediate bend, and then shaped into a J-shape using a final hole-type roll where the ends of the flanges on the short and long sides are on the same horizontal plane.The end surfaces of the left and right flanges are smoothed, and rolling is completed to achieve the desired shape. This is a method for manufacturing a J-shaped rib material, which is characterized by cutting the material to a length of .

In the past, various types of steel sections have been manufactured by hot rolling, but equilateral or scalene angle section steels are manufactured in such a way that the apex angle of the crest where the left and right flanges intersect is set at a right angle (5th angle).
The hole design is based on the shape shown in Fig. y) and the rounding of r ₁ and r ₂ at the tip of the flange.
Rolling is also manufactured with this as an important point.

In the present invention, on the contrary, as shown in FIG. 4, an R is applied to the intersection peaks of the left and right flanges from the first forming hole mold, and the shape of the R is gradually changed in the subsequent hole molds. In addition, the left and right flange tips are the fifth
By eliminating the roundness of the r ₁ and r ₂ of the regular angle steel shown in the figure and making them flat, we manufacture a J-beam with the required dimensional cross section as shown in Fig. 6 in the final hole shape. Furthermore, the present invention proposes a method of manufacturing a rib material by cold cutting this J-shaped steel into a predetermined length.

Therefore, the rib material according to the present invention has the same wall thickness over its entire length, and of course the wall thickness at the end portion where the 90° radius is applied can also be made the same.

In addition, as shown in Figure 4, the opening point of the roll hole type
O ₁ , O ₂ ...O ₁₀ are arranged alternately on the upper roll side and the lower roll side, and the flange end faces Q ₁ and Q ₂ in Fig. 6 are formed to be smooth at right angles, so when welding and assembling them to segments as rib materials. There is no need for additional bevel processing.

The present invention will be explained below with reference to the drawings.

In the manufacturing method of the present invention, a billet having a cross section of A shown in FIG. 4 is passed through rough rolling and intermediate rolling multiple times to create a cross section Kal4 of the first forming hole in the finishing series. Give R ₆ roundness to the intersection of this Kal 4 flange. As is well known, when manufacturing the scalene angle steel shown in Fig. 5, the side lengths of the left and right flanges are different, so during rolling, the lateral component of force is large on the long side, so thrust acts and the upper roll It is easy to escape to the long side.

This results in uneven wall thickness between the left and right flanges and a lack of wall thickness at the apex angle y, which is called sagging. For this reason, various improvements have been made to the hole shape and guidance device. In particular, the J-shaped steel according to the present invention, unlike ordinary angle steel, has a large radius at the intersection of the flanges, so the rolled steel tends to escape to the long side. Also, in order to improve the welding conditions for the flange tip, Q ₁ ,
It is necessary to finish it flat like Q ₂ . For this reason, in the roll hole type, care is taken to prevent the steel material from escaping from side to side, and measures are taken regarding the guiding device.

R ₆ and R ₅ at the flange intersection of Kal 4 in Figure 4 are changed to R ₄ and R ₃ in the next Kal 5, but the upper part of the flange intersection in 5 passes from the next Kal 6 to Kal 10 of the final hole type is changed. R ₂ and the lower part were all made to have the same R diameter as R ₁ .

Also, R ₂ of the flange intersection from Kal6 to Kal9
The intersection of R ₁ and the left and right flat flange portions gives the same R ₇ in all four passes. Also Kal7
The finished angle θ of the intersection from to Kal10 is 4
Give all passes 90°.

With the hole configuration as described above, the rounded rising part of the flange intersection that does not have a triangular apex angle can be
I was able to firm it up firmly on both sides of the top and bottom rolls.

Also, regarding the widths of the holes shown from W ₄ to W ₁₀ in FIG. 4, Kal 6 to Kal 9 are made approximately equal to prevent the steel material from collapsing. However, the width of Kal6
W ₆ > Width of Kal7 W ₇ , Width of Kal7 W ₇ > Width of Kal8,
W ₈ Width of Kal8 W ₈ > Width of Kal9 W ₉ The width of the previous Kal is made slightly wider than the later Kal. Therefore, in order to avoid unfavorable biting conditions, we adopted an inlet fuel ring with a roller as described below.

Also, when the steel material is rolled down, the overall length of the flange increases little by little. Although the relationship between this lateral expansion and the above-mentioned setting of the Kal width to be approximately equal is contradictory, it can be accommodated by raising the height of the R portion of the flange intersection, as shown in FIG. That is, h ₆ < h ₇ < h ₈
<h ₉ . This means that the height gradually approaches h10 of Kal10 of the final hole mold, which also has the effect of improving the biting into the final hole mold.

Also, as shown in Figure 4, the rising angle θ of the flange intersection with R from Kal4 to Kal9
(90°) is equally distributed in 45° increments along the center line with respect to the horizontal axis of the roll.

As shown in Figure 6, when the final hole type Kal10 is placed on a roll with the flange intersection angle of 90° equally distributed at 45° increments to the center line, Kal9
Since the flat portions of the left and right flanges are on the same horizontal plane, when Kal 9 bites into Kal 10, the left and right flanges are not balanced, making it difficult to bite and causing side-to-side wobbling.

In order to eliminate these drawbacks, as shown in Kal10 in the figure, the center line is tilted by η with respect to the horizontal axis so that the flange tips e and e' of the short side and long side are on the same horizontal plane. This allows the left and right flanges of the steel material that has exited Kal9 to be engaged with Kal10 at the same time.

Also, make the flat parts near both ends of the left and right flanges from Kal6 onwards in Figure 4 the same horizontal plane as much as possible.
The ends of O ₆ , O ₇ , O ₈ , O ₉ , O ₁₀ are as per flat steel rolling.
The edges were alternately touched with upper and lower rolls to improve welding conditions for the flat edges.

Furthermore, in order to stabilize the guidance of the steel material to the rolls, Führung has installed guide rollers among the inlet guidance devices from Kal6 to Kal10.
The left and right flanges are made to engage the roll through rotational contact. A fuel ring made from a steel plate or cast wears due to friction with the flange tip, making the product unstable. In FIG. 7, f shows the fuel ring, e shows the guide roller, and a shows the cross section of the steel material during the approach.

From Kal6 to Kal10, upper slide b in the figure,
The Kal before biting into the next Kal with a lower srace c.
Match the cross section of the slats with the top and bottom shapes of the slats, and maintain the center of the R-shaped rising part of the steel material with the top and bottom slats. The entrance side has a flat top and bottom shape to make it easier to enter.

Next, FIG. 8 shows the entrance slot of the final hole type Kal10. Entrance/exit fuel lungs, exit funds, etc. are omitted. In Fig. 8, j and k are rolls, and the g-shaped steel material exiting Kal9 passes through the rolls and becomes h-shaped J section steel. b' indicates the upper slope of the entrance, and c' indicates the lower slope of the entrance.

The principle of this upper and lower slivers is the same as b and c in Fig. 7, but the steel material maintained by the slivers b' and c' has a cross section of Kal9 in the shape of g shown in Fig. 8 2. However, the shape of the inside of this slither is that the cross section on the entrance side is the shape of g in view A-A, that is, the shape of Kal9, but it gradually deforms and becomes the shape of i at view B-B. doing. This has a flange portion with a medium slope between the left and right flanges of Kal9 and Kal10.

The steel material that has passed Kal9 of g is from view A-A to view B-
While passing through B, the flange portion is deformed into the shape of an i by the upper and lower slivers, and bites into Kal10. This makes the insertion into the final hole mold very smooth due to the intermediate bending.

It is recommended to use special heat-resistant steel for the material of the upper and lower slides to prevent seizure.

By using the above-mentioned groove roll and guidance device, the intersection of the flanges in the final groove shape has the required radius, the left and right tips are flat, and the flanges have an equal thickness of t in all parts. Manufacture equal-sided J-beams. J of equal sides of left and right flanges
Shaped steel is manufactured in exactly the same manner.

The present invention has a structure in which the intersection of the left and right flanges has an apex angle of 90° and the tip of the flange has a small roundness. However, the feature is that the required rib material is manufactured by hot rolling a steel material with the same shape and dimensions as the flat cold-formed material, and then cold cutting it.

Since the J-shaped steel obtained by the present invention can have the R part as thick as or thicker than the flange part, it has higher strength than cold-formed steel if the dimensions are the same. benefits can be obtained.

Furthermore, if the rib material is melt-cut from a steel plate and then cut with a shear, fusing residue and cut burrs will adhere, so these are removed with a grinder, but there is no need for that effort.

Furthermore, when cutting flat steel to a predetermined length, cutting burrs occur at both ends, and cracks are likely to occur during bending, but since no bending is performed, no cracks occur. There is no need for heat treatment of the edges or anything else.

In addition, for products with dimensions that are used in large quantities, if the product is hot-formed and then cut to a predetermined length, steps such as press molding can be naturally omitted.

Also, if the dimensions are the same, it is possible to make a material that is stronger than the steel plate or flat steel used for cold forming.

Furthermore, since there is no need to consider bending performance, materials with good corrosion resistance can be used.

Moreover, since it is manufactured by hot rolling, it is possible to measure long lengths. Therefore, it can be applied to long rib materials such as shipbuilding parts, vehicle parts, civil engineering construction parts, and other general machine parts.

In addition, it is possible to deliver parts of a predetermined length, such as segment rib materials, at the required time and in the required quantity.
This simplifies management tasks such as material yard, horizontal handling work, rust prevention, and other tasks at the processing factory on the user side.

Furthermore, for products with dimensions similar to those of conventional equilateral and scalene angle bars, holes can be provided on the same roll, reducing the effort required to change rolls and creating the required J by simply changing the holes. It is also possible to obtain shaped steel.

Examples of the present invention will be described below.

A 124×124 sized billest (material SM50) was heated to 1150°C in a heating furnace, rough rolled and intermediate rolled in a section rolling mill to obtain a rectangular cross section with a thickness of 40 mm, and then the groove series of the present invention was obtained. Rolled with

The forming hole mold of the present invention is provided after the fourth pass roll of the finishing row, and the angle of the R part of the sixth pass roll is 105°, and the R part of the seventh, eighth, ninth, and tenth pass rolls (final hole mold) is provided. The rolls were arranged at an angle of 90°.

The obtained J-shaped steel was cold cut to the dimensions of the vertical rib material of the steel segment, and used for welding. As a result, the steel segment showed mechanical properties equivalent to or superior to those of cold press-formed rib material.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a flat steel plate, Fig. 2 is a schematic diagram of conventional press working, Fig. 3 is an explanatory diagram of the process of the conventional example, Fig. 4 is an explanatory diagram of the process of the present invention, and Fig. 5 is the conventional example. 6 is a cross-sectional view of the scalene angle steel, FIG. 6 is a cross-sectional view of the rib material of the present invention, and FIG. 7 is a partial cross-sectional view of the process of the present invention.
FIG. 8 is a partial schematic diagram of the process of the present invention. 10; flat steel plate, 12; shear, 13; burr,
14; Kratsk.

Claims (1)

[Claims] 1. When manufacturing a shaped steel having a flange by hot rolling, rolling is started using a shaping hole in which the left and right intersections of the flanges have an R-shape, and the R-shape is gradually approximated to the product shape. At the same time, in a guiding device having left and right vertical guide rolls between the final groove roll and the forming groove roll one pass before the final groove roll, an intermediate bend is given to the material to be processed, and the short and long sides are folded. A method for manufacturing a J-shaped rib material, which comprises shaping the material into a J-shape using a final hole-type roll with flanged tips on the same horizontal plane, finishing rolling by smoothing the left and right flange end surfaces, and cutting the material into a desired length.