JPH09108706A - Continuous joint shape steel having left-right asymmetric joint and rolling method thereof - Google Patents

Abstract

(57) [Abstract] [Problem] When manufacturing a continuous joint shape steel having asymmetrical joints by rolling, defective joint shape, bending during rolling,
The thickness of the web and claws can be made to any desired size according to the purpose of use without reducing the roll unit, and the opening width of the claw tip of the female joint can be fixed and fit. To provide a continuous joint shaped steel having a left-right asymmetric joint having excellent combined strength and means for producing the same. SOLUTION: An edger mill in an intermediate rolling step in a rolling process of a continuous joint shape steel having a left-right asymmetric joint buckles only the tip end of the flange on the female joint side to bend it to the outside of the flange, and then a flange bending forming mill and By bending the flange on the female joint side with a finishing mill, claw portions 1bf of the female joint portion formed into a substantially arc shape are formed on both sides in the width direction of the web 1a having a predetermined thickness and width. A continuous joint shaped steel having a bent portion 1s formed at the tip and a constant opening width k at the tip of the claw can be formed. When connecting the female joint portion and the male joint portion of this continuous joint shaped steel, The fitting strength is improved by engaging the bent portion 1s and the male joint portion 1bm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous joint section steel having a left-right asymmetric joint and a method for rolling the section steel.

[0002]

2. Description of the Related Art FIG. 9 shows an example of the most typical conventional shape of a continuous joint shape steel 1 having a left-right asymmetric joint which is the subject of the present invention. In the figure, a continuous joint section steel 1 having a left-right asymmetric joint is a web 1 formed with a predetermined web thickness TW.
A female joint portion 1bf having a thickness TFf and a male joint portion 1bm having a thickness TFm are provided at both left and right ends of a.

The distance W between the center portions of the female joint portion 1bf and the male joint portion 1bm is called the effective width. Further, the product size of the continuous joint shape steel 1 having the left-right asymmetric joint has the same effective width W in the series, and has various web thicknesses TW and joint portion thicknesses TFf (TFm).

A continuous joint shaped steel having these asymmetric joints is generally used for a box type sheet pile or a circular cell as shown in FIGS. 10 (a) and 10 (b). FIG.
(A) is an example in which so-called box-shaped sheet piles are joined by welding H-section steel 3 to a web 1a of continuous joint section steel 1 having two left-right asymmetric joints to form a section having an H-section. ,
FIG. 10B shows an example in which the female joint portion 1bf and the male joint portion 1bm of the continuous joint shaped steel having a left-right asymmetric joint are connected in a circle.

The characteristics of this steel box-type sheet pile are that the wall thickness can be made thin because of its excellent cross-sectional performance, and the surfaces of the constituent members are smooth, making it suitable for the wall function and facilitating a composite structure with concrete. The concrete uses are earth retaining walls, foundation piles, earthquake-resistant walls for permanent construction, landslide deep foundation piles, etc.

[0006] Now, with the recent trend of active development of underground space, increasing depth and construction in urban areas have become mainstream, and a continuous joint having left and right asymmetric joints, which is a basic member of the box-type sheet pile, has been introduced. It is required to improve the fitting property of the joint shaped steel 1 with an emphasis on workability, and it is an important issue to provide a product series having a wide range of sectional performance.

Particularly when constructing a deep underground continuous wall, since the earth pressure is small near the ground, the web thickness TW of the continuous joint shaped steel 1 having a left-right asymmetric joint may be small, but the earth pressure increases. Inside the ground, it is necessary to increase the web thickness TW according to the increase in earth pressure to increase the rigidity of the box-type sheet pile.

In this case, the joint thicknesses TFf and TFm of the joint portion
Also increases as the web thickness TW increases. Continuous joint shaped steel 1 having left-right asymmetric joints with different plate thickness during construction 1
A relatively short box-shaped sheet pile consisting of is inserted into the muddy ground in order, and is laid by adding bolts in the longitudinal direction.

[0009] As a general manufacturing means of continuous joint shaped steel, there is a so-called caliber rolling method of the conventional straight steel sheet pile shown in FIG. In the figure, the rough-shaped billet BB
Is a raw material produced in a slab or a casting plant, and this raw material BB is rolled into a product by successively using each of the hole dies of K13 to K1. This method mainly uses the grinding action by the side walls of the upper and lower rolls. Because of the above rolling, the type of each hole type is a closed hole type (Closed Pass) is an indispensable constituent element of the hole type series.

For this reason, the amount of roll refurbishment due to the wear of the hole type is large, the unit consumption of the roll is high, and a large amount of rolling oil and roll cooling water are required. Becomes unstable and rolling work becomes extremely difficult. In addition, since the number of cavities is large, a long roll body length is required, and it is difficult to produce a wide continuous joint type steel having a large effective width W.

As a solution to this problem, there is a so-called universal rolling method disclosed in Japanese Examined Patent Publication No. 47-47784 as a rolling method in which a material defect forming a joint portion is directly subjected to reduction to remove defects in forming. A representative example of this universal rolling method is shown in FIG. 12, and it is possible to manufacture from a rectangular steel strip SL by performing universal rolling at K4-1, 2, 3 in the intermediate rolling section.

Further, in Japanese Patent Publication No. 58-38241, the finish universal rolling method is also adopted for the finish hole type K1 and the hole width of the left and right joints is regulated by the vertical rolls fitted in the left and right joints. A means for suppressing the variation of is well known. However, even in this method, the upper and lower horizontal rolls require a relatively deep and complicated hole shape, and the above-mentioned problems cannot be solved.

As another measure, the shape of the straight-lined steel sheet pile is changed to a product shape that is easy to roll, so that so-called universal rolling equipment for H-section steel can be used and rolling can be performed by means similar to the rolling method for H-section steel. There is an improved way. FIG.
Japanese Patent Publication No. 55-11921 and Japanese Patent Publication No. 55-1913 shown in FIG. 14 are examples, and the problems in the case of rolling in the hole type having the closed hole type are solved. However, it is intended to manufacture a linear steel sheet pile of a specific size.

The inventors of the present invention applied the conventional straight-line steel sheet pile rolling method to the web thickness and the flange (claw).
Due to the limitations of the molding, the part thicknesses must be limited to a very narrow range, and the same roll set can be used to achieve various nail sizes and web thicknesses of various sizes. In order to solve the problem that it is impossible to roll a continuous joint shape steel having a left-right asymmetric joint having a constant effective width and a substantially constant opening width, JP-A-4-330113 has already proposed the technology. ing.

In this rolling method, as shown in FIG. 8, a left-right asymmetric dogbone-shaped crude shaped material formed in a rough rolling step is subjected to intermediate rolling mills U and E, and a flange portion has a predetermined thickness and left-right asymmetry. Of an intermediate rolled material having a predetermined width and a web portion having a predetermined thickness and a constant inner width and having a substantially asymmetrical H-shaped cross section, and then, in the width direction on the female joint side of the intermediate finish rolling mill S. The upper and lower horizontal rolls 22a and 22b having the stoppers at their ends bend the flanges outward while restraining the flange tips of the female joints.

After that, the upper and lower horizontal rolls 23 of the finishing mill F
It is characterized in that the gap between a and 23b is adjusted to have a predetermined web thickness and a claw part shape / thickness, and finish rolling is performed to a continuous joint shaped steel having a joint opening width that is substantially constant and an effective width is constant. Is a rolling method of continuous joint shaped steel having a left-right asymmetric joint.

However, since the continuous joint shaped steel having this left-right asymmetrical joint places importance on the fitting property with the connecting member for the purpose of use, it is a continuous joint having a left-right asymmetrical joint as compared with the straight type steel sheet pile. There is a problem that the strength for connecting the female joint portion and the male joint portion of the shaped steel, that is, the so-called fitting strength, becomes considerably small. In order to solve this problem, it is necessary to improve the shape of the continuous joint shaped steel having a left-right asymmetric joint.

[0018]

DISCLOSURE OF THE INVENTION The present invention, when producing a continuous joint shape steel having a left-right asymmetric joint by rolling, causes a defective joint shape, a bend during rolling, a decrease in roll unit consumption, etc. Without any need, the web thickness and claw thickness can be made into any desired size according to the purpose of the application, and the opening width of the claw tip part is constant, and a left-right asymmetric joint with excellent fitting strength is provided. It is an object of the present invention to provide a shaped steel and means for manufacturing the shaped steel.

[0019]

The gist of the present invention is as follows. (1) A claw having a female joint and a male joint that are fitted to each other in the width direction of a web having a predetermined thickness and width, and the female joint bends a flange outward in the width direction of the web in a substantially arc shape. The continuous joint shaped steel having a left-right asymmetric joint characterized in that the tip of the claw is bent inward, and the opening width of the claw tip facing the claw is fixed.

(2) A continuous joint shape steel having a left-right asymmetric joint according to (1), characterized in that the outer surface of the male joint is a straight line orthogonal to the web. (3) The continuous joint having the left-right asymmetric joint according to (1), wherein the claws of the male joint are curved inward in the width direction of the web or bent outward in the width direction in a substantially arc shape or in a U-shape. Joint type steel.

(4) Rough rolling step in which a breakdown mill for forming a left-right asymmetric dogbone-shaped rough shaped material is arranged, and a universal mill for forming a web and a flange to a predetermined thickness and a left-right asymmetric predetermined width A continuous joint type with left-right asymmetric joints by an intermediate rolling process with an edger mill with a variable hole depth mechanism, an intermediate finishing process with a flange bending mill, and a finishing rolling process with a finishing mill. In the method of rolling steel, the edger mill performs width reduction of the asymmetrical flange to a predetermined flange width, and at the final pass of this width reduction rolling, only the female joint side buckles the flange tip to the outside of the flange. It is bent to form an approximately H-shaped intermediate rolled material in which only the tip of the flange has a large tilt angle. By the horizontal rolls of the flange bending forming mill, which has a stopper portion at the end in the width direction and a curved portion formed of a region for shaping the flange tip and a region for bending the flange, After shaping the flange tip into a predetermined shape while restraining the end surface of the flange tip on the female joint side and bending the flange, adjust the gap between the upper and lower horizontal rolls with the finishing mill to make the web have a predetermined thickness. A continuous joint shaped steel having a left-right asymmetric joint characterized by being shaped into a shape such that the female joint side flange is curved into a predetermined claw shape, and the opening width of the female joint side claw tip is finished to be almost constant. Rolling method.

(5) Flange of the male joint portion is balanced with the stretching that occurs when the female joint portion is bend-formed without bending the flange of the intermediate rolled material on the male joint side by the bending and finishing mills. A rolling method for a continuous joint shaped steel having a left-right asymmetric joint according to (4), characterized in that width reduction or flange thickness reduction is performed.

(6) After the male joint side flange of the intermediate rolled material is bent inward or outward in the width direction of the web in a substantially arc shape or in a U-shape by the upper and lower horizontal rolls of the flange bending mill. The method for rolling continuous shaped steel bars having a left-right asymmetric joint according to (4), characterized in that the flange portion on the male joint side is curved or bent into a predetermined claw shape with a finishing mill.

(7) The side surface on the female joint side of the horizontal roll of the universal mill in the intermediate rolling step is formed into a taper or a curve whose width becomes wider toward the axial center of the roll at a predetermined increase rate, and the flange tip end is formed. The outer diameter of the rolling section is increased so that the rate of increase of the cylinder width is further increased, and the vertical rolls on the female joint side of the universal mill in the intermediate rolling process have smaller diameters at the flange tip portions on both axial sides than the central portion. Left and right according to (4), (5) or (6), characterized in that the tip end of the flange on the female joint side is bent by rolling it with a horizontal roll and a vertical roll to have a tapered or curved outer shape. Rolling method for continuous joint shaped steel with asymmetric joint.

(8) In the intermediate rolling process, the side of the horizontal joint of the horizontal roll of the universal mill on the female joint side is tapered such that the cylinder width becomes wider toward the axial center of the roll and only the portion for rolling the flange tip end is a constant cylinder. (4), (5) or (6), characterized in that the horizontal roll and the vertical roll on the female joint side having a flat flange pressure lower surface are used for rolling, and the outer shape is a combination of straight lines having a width. Rolling method for continuous joint shaped steel with left-right asymmetric joint.

(9) After the outer surface of the flange other than the flange tip portion on the female joint side is water-cooled in the intermediate rolling step, the flange tip portion on the female joint side is subjected to the final pass of the flange width reduction rolling by the edger mill in the intermediate rolling step. A rolling method for a continuous joint shaped steel having a left-right asymmetric joint according to (4), (5), (6), (7) or (8), characterized by bending.

(10) The hole shape on the female joint side of the upper and lower horizontal rolls of the flange bending mill having the curved portion composed of the region for shaping the flange tip and the region for bending the flange, and the female joint for the intermediate rolled material. Side end of the flange end portion of the side of the wedge-shaped vertical roll is used to shape the flange end portion of the female joint into a predetermined shape and bend the flange (4), (5),
(6), (7), (8) or the rolling method of a continuous joint shaped steel having a left-right asymmetric joint according to (9).

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The operation of the present invention will be described below with reference to the drawings. The continuous joint shape steel having the left-right asymmetric joint of the present invention has a web 1 as shown in FIGS. 1 (a) to 1 (e).
a, the female joint portion 1bf, and the male joint portion 1bm, the effective width W of which is constant within the series, and the web thickness Tw is formed to a predetermined size corresponding to the laying position.

Further, the claw tip portion of the female joint portion 1bf, which is bent at one end in the web width direction of the continuous joint shape steel having the left-right asymmetric joint of the present invention with a constant curvature, has the bending characteristic of the present invention. The part 1s is formed. As will be described later, the bent joint 1s and the male joint portion 1bm of the continuous joint shaped steel having another left-right asymmetric joint shown by the broken line are engaged with each other to obtain a desired fitting strength. Furthermore, the female joint portion 1
The opening width k of bf is constant and maintains a good fitting property with the male joint portion 1bm.

FIG. 2 is an enlarged view of a female joint portion 1bf of the present invention having a bent portion 1s, and FIG. 3 is an enlarged view of a conventional female joint portion 1cf without the bent portion 1s shown for comparison.
All of them exemplify a state in which they are fitted to the male joint portion 1bm of the continuous joint shaped steel having another left-right asymmetric joint.
When the pulling force F2 is applied to the fitted joints in practical use, the conventional female joint portion 1cf without the bent portion 1s of FIG. 3 spreads in the direction of the arrow as shown by the broken line at the tip of its claw to open. The width k expands to k2, and finally becomes larger than the claw width g of the male joint portion 1bm, and the male joint portion 1bm separates.

On the other hand, as shown in FIG. 2, when the female joint portion 1bf of the present invention also receives a tensile force F1, it spreads outward similarly to the female joint portion 1cf shown in FIG. Although it has a shape, since the bent portion 1s is provided at the tip of the claw, the male joint portion 1bm meshes with the bent portion 1s of the tip of the claw, and the opening width k expands only to k1 which is considerably smaller than k2. After that, the tensile force acts in a state where the male joint portion 1bm meshes with the bent portion 1s of the claw tip portion, so that even if a considerably large tensile force acts as compared with the case of FIG.
bm does not separate, and as a result, the fitting strength increases.

Next, FIGS. 4 (a) and 4 (b) show an example of a rolling process when the present invention is applied to the production of a continuous joint shape steel having a left-right asymmetric joint. In the rough rolling step of the present invention, the upper and lower horizontal rolls of the breakdown mill BD perform edging a plurality of times using a slab having a rectangular cross section or a dogbone-shaped steel slab as a raw material to form a left-right asymmetric dogbone-shaped rough shaped material. This is the same process as the rough forming of a shape steel having a left-right asymmetrical flange such as a well-known asymmetrical H-section steel, and thus detailed description thereof will be omitted.

Next, in the intermediate rolling step, the rough shaped material is cut into a predetermined web thickness, a flange thickness, and a left-right asymmetric flange width by a universal mill U and an edger mill E having a mechanism for independently adjusting the right and left hole die depths. Web 1a
U, a female joint side flange 1bUf, and a male joint side flange 1bUm. Horizontal roll 2 here
As for the outer shapes of 0a and 20b, the surface which presses down the web 1aU of the intermediate rough rolled material is flat as in the technique of the above-mentioned Japanese Patent Laid-Open No. 4-330113, and preferably the side surface contacting the inner surface of the flange has an inclination angle α (approximately 3 to 10 °), and can be commonly used as a horizontal roll of a conventional universal mill for H-shaped steel rolling.

Further, the vertical rolls 30a and 30b have a flat surface for pressing the flange of the intermediate rough rolled material.
This can also be used in common with the vertical roll of the conventional universal mill for H-shaped steel rolling. By adjusting the gap between the horizontal rolls 20a and 20b and the vertical rolls 30a and 30b, the desired web thickness and flange thickness can be obtained.
Further, the intermediate rough rolled material rolled by the universal mill U is the upper and lower rolls 21a, 21b of the edger mill E having a left and right hole type depth independently variable mechanism arranged in a pair with the universal mill U, mainly on the female joint side. Flange 1bE
f, the tip of the flange 1bEm on the male joint side is shaped.

The upper and lower rolls 21a of the edger mill E,
21b has a mechanism capable of independently changing the left and right hole type depths, so that the flange 1b on the female joint side is restrained while restraining the web.
Ef, the tip of the flange 1bEm on the male joint side can be pressed down. As a feature of the present invention, a large width reduction of the flange 1bEf on the female joint side is performed while restraining the web in the final rolling pass of the rolling by the edger mill having the left and right hole type depth independently variable mechanism, and the flange 1bEf on the female joint side is performed. Only the tip portion of is bent to form the bent portion 1sE.

If an edger roll having a constant hole depth is used, in order to perform a large reduction of the flange width in the final rolling pass of the edger mill, it is inevitable that the web is not restrained until the previous rolling pass. Since the flange width is reduced by the edger mill, the dimensional accuracy deteriorates and the shape collapses. On the other hand, in the present invention, since the edger mill having the left-right hole type depth independent variable mechanism is used as described above, it is possible to perform flange width reduction while restraining the web in each rolling pass, and high dimensional accuracy and goodness The shape can be maintained.

As a mechanism for varying the hole depth, the inventors of the present invention have previously devised the Japanese Patent Laid-Open No. 62-77107 or the Japanese Patent Laid-Open No. 62-77107.
An edger roll having a hole type depth varying mechanism described in Japanese Patent Publication No. 77101 is used. In this example, one universal mill U and one edger mill E are arranged to form a pair, but a plurality of pairs of rolling mills may be used as necessary.

In the next flange bending process, intermediate rough rolling of substantially asymmetric H-shaped cross sections having various web thicknesses rolled by the rough universal mill U and the edger mill E by the upper and lower horizontal rolls 22a and 22b of the flange bending mill S. The flange portion on the female joint side of the material is bent outward, and while the end surface of the flange tip portion on the female joint side is constrained by the end surfaces of the upper and lower horizontal rolls 22a and 22b, the flange tip on the female joint side has a predetermined shape. By shaping into a bent portion 1sS, an intermediate finishing material composed of the web 1aS, the female joint side flange 1bSf and the male joint side flange 1bSm having the bent portion 1sS at the tip is molded.

In the final finish rolling step, the web of the intermediate finish material is pressed down by the upper and lower horizontal rolls 23a and 23b of the finish mill F, and the finish bending of the flange on the female joint side is performed, so that both sides of the web 1a in the width direction are processed. Has a female joint portion 1bf bent and formed in a substantially arc shape, has a bent portion 1s only at the tip end of the claw, and has a left-right asymmetric joint of the present invention in which the opening width of the tip end of the claw is constant left and right. Finished into a continuous joint shaped steel.

In FIG. 4B, the upper and lower horizontal rolls 22a and 22b of the flange bending forming mill S and the finishing mill F are shown.
The method of forming the male joint portion 1bm having a cross-sectional shape curved inward in the web width direction as shown in FIG. 1 (b) by the upper and lower horizontal rolls 23a and 23b has been illustrated.
Similarly, the male joint portion 1bm shown in (e) is curved or bent by the upper and lower horizontal rolls 22a and 22b of the flange bending forming mill S and the upper and lower horizontal rolls 23a and 23b of the finishing mill F.

However, in FIG. 1 (a), flange bending of the male joint portion 1bm in the flange bending forming mill S and the finishing mill F is not carried out, but in order to balance the stretching which occurs when the female joint portion is formed by bending. Finishing is done with almost the same shape as the flange after the intermediate rolling process, only by slightly reducing the flange width or the flange thickness of the male joint portion.

The bent portion 1sE at the tip of the flange on the female joint side, which is a feature of the present invention, is the final rolling pass of the edger mill E having the independent variable mechanism of the left and right hole type depths shown in FIG. 4B. A large width reduction of the flange on the female joint side is performed, and only the tip of the flange is buckled.

At this time, the inner surface of the flange is constrained by the side surfaces of the upper and lower rolls 21a and 21b of the edger mill E, so that the tip of the flange buckles and bends outward. Further, the tilt angle of the bent portion increases as the reduction amount of the flange width increases.

A method of adjusting the tilt angle of the bent portion thus molded and its proper tilt angle will be described below. FIG. 5A shows an example of a female joint portion formed by forming an angle between the extension line of the bent portion 1s after finishing bending and the web 1a at 90 °. The angle formed by the extension line of the bent portion 1s after the finish bending process and the web 1a is the angle θ of the bent portion after the edger rolling plus the angle φ given by the finish bending process. The given angle φ is geometrically determined if the bending start point SP is determined. Therefore, the flange width reduction amount in edger rolling is changed so as to satisfy the above θ = 90 ° −φ, and the female joint at that stage is changed. The bending amount of the front end of the side flange may be adjusted.

The proper tilt angle of the bent portion is 1bm for the male joint.
It is determined so that the end surface of the tip of the and the inner corner of the bent portion 1s smoothly mesh with each other and the stopper effect by the bent portion is sufficiently exerted. Practically, the angle between the extension line of the bent portion 1s after finishing bending and the web 1a (θ
+ Φ) may be about 90 ° to 120 °.

Next, the proper length of the bent portion 1s is determined from the following three points. That is, (1) the length that allows the required buckling due to the flange width reduction by the edger mill,
(2) A length that properly meshes with the male joint portion and sufficiently exerts the stopper effect by the bent portion, (3) A length that maintains good fitability between the female joint portion and the male joint portion, Need to be satisfied.

Regarding (1), the longer the length of the bent portion, the easier it is to buckle, and regarding (2) and (3), if the length of the bent portion 1s exceeds a certain length, a problem occurs.
When the length L of the bent portion is long as shown in FIG. 5 (b), the angle of the bent portion cannot satisfy the above-mentioned necessary condition, and therefore the fitting strength improvement by the bent portion cannot be expected.

Further, since the space inside the claw portion of the continuous joint shape steel becomes narrow, the good fitting property of the male joint portion cannot be maintained. Considering the above (1) to (3), it is practically appropriate that the flange tip thickness TFE on the female joint side is about 1 to 3 times.

As a method of controlling the length of the bent portion 1s, as shown in FIG. 6 (a), the water cooling device CW on the outer surface of the flange should cause buckling on the outer surface of the flange 1bUf on the female joint side. A method other than the range, that is, a method of increasing the deformation resistance by cooling only the range RF, or as shown in FIG. 6 (b), the roll side surface on the female joint side is cut from the web pressure lower surface toward the roll axial center, The horizontal rolls 20c and 20d of the universal mill in the intermediate rolling process, which have an outer shape that forms a taper or a curve that is partially changed so that the increase rate of the body width of the portion where the flange tip portion is rolled becomes large, in particular, becomes wider. And universal rolling using the vertical rolls 30c on the female joint side, which have an outer shape that forms a taper or a curve in which the flange tip portions on both axial sides are smaller in diameter than the central portion There is a method of preliminarily forming a bending portion at the floor.

Alternatively, as shown in FIG. 6 (c), the side wall of the roll on the female joint side becomes wider from the pressure lower surface of the web toward the axial center of the roll, but the front end of the flange on the female joint side is rolled. Only the flange tip part is used by using horizontal rolls 20e and 20f of the universal mill in the intermediate rolling process in which the shape is partially changed to have a constant cylinder width and the vertical roll on the female joint side with a flat flange pressure lower surface. A method of changing the flange thickness in advance so that the buckles will buckle may be adopted.

However, in the method of FIG. 6 (a), since the cooling water flows down, the tip of the lower flange may also be cooled and the shape of the bent portion after edger rolling may become slightly uneven in the upper and lower parts. 6 (b) and 6 (c) is a more reliable control method. However, the method of FIG. 6 (a) has an advantage that the shape of the bent portion can be arbitrarily formed to some extent by using the same roll by adjusting the cooling region.

As a rolling method in the flange bending mill S, as shown in FIG. 7, it serves as upper and lower horizontal rolls 22c and 22d having no stopper portion at the widthwise end of the female joint and a stopper portion. A method of forming with a wedge type vertical roll TF can also be applied.

[0053]

EXAMPLES In the following, as examples, a continuous joint type having a left-right asymmetric joint of the present invention having a bent portion at a claw tip portion of a female joint side and a continuous joint type having a conventional left-right asymmetric joint having no bending portion The results of measuring and comparing the fitting strengths of shaped steels will be described.

The common dimensions of the continuous joint shape steel having the left-right asymmetric joint used are as follows: the web thickness is 12 mm, the effective width is 700 mm, and the female joint has a nail tip thickness of 8 mm and an average nail thickness. Is set to 12 mm, the center length of the claw is set to 200 mm, and the radius of curvature of the claw is set to 45 mm, and the male joint has the same shape as 1 bm of FIG. 1 (b), the thickness of the claw is 12 mm, and the center length of the claw is 65m
m and the radius of curvature of the claw portion were set to 45 mm.

Further, in the continuous joint shape steel having the left-right asymmetric joint of the present invention, each of the four claw tips has a length of 20 mm.
Is provided with a bent portion. In accordance with the JIS standard, the fitting strength test cuts out a 100 mm test piece from the rolled material in the rolling direction and engages the female and male joints of the continuous joint shaped steel with left and right asymmetric joints and pulls them. The test was performed with the shaft and the web surface of the test piece set parallel to each other. Table 1
Shows the fitting strength obtained by converting the test results per 1 m of wall length.

[0056]

[Table 1]

From the above results, the fitting strength of the continuous joint shape steel having the left-right asymmetric joint of the present invention is about 1.5 times that of the conventional continuous joint shape steel having the left-right asymmetric joint. It is clear that it is extremely good. It was also confirmed that the fittability was good.

[0058]

EFFECTS OF THE INVENTION The continuous joint shape steel having the left-right asymmetric joint of the present invention has a good joint fitting property and extremely high fitting strength. In addition, even when manufacturing this, there is no need for major equipment changes, and a continuous joint shaped steel having a multi-size web thickness and claw thickness left-right asymmetric joint with the same roll set of the existing H-shaped steel rolling mill row is produced. You can freely create them.

The size of the materials used can be integrated, the number of rolling rolls and other auxiliary parts is small, and the number of roll changes can be minimized. Further, since it is possible to efficiently manufacture a continuous joint shaped steel having high quality and multi-size asymmetrical joints even in a small lot, it is possible to meet market needs promptly and accurately.

[Brief description of the drawings]

FIG. 1 (a), (b), (c), (d), (e) is a sectional view showing an example of a continuous joint shaped steel having a left-right asymmetric joint of the present invention.

FIG. 2 is an explanatory view showing a fitting state of a female joint portion and a male joint portion each of which has a bent portion according to the present invention.

FIG. 3 is an explanatory view showing a conventional fitting state of a female joint portion and a male joint portion, each of which includes a claw having no bent portion.

4 (a) and 4 (b) are explanatory views of an example of a rolling method when the present invention is applied to the production of a continuous joint shape steel having a left-right asymmetric joint.

5A is an explanatory diagram of a method for determining an appropriate angle of a bent portion according to the present invention, and FIG. 5B is an explanatory diagram of a defect when the bent portion is too long.

6 (a), (b) and (c) are explanatory views showing an example of a method of controlling the length of a bent portion of the present invention.

FIG. 7 is an explanatory diagram showing an example of a rolling method in a flange bending mill.

FIG. 8 is an explanatory view showing a rolling method for a continuous joint shape steel having a conventional left-right asymmetric joint.

FIG. 9 is a sectional view showing an example of a continuous joint shape steel having a conventional left-right asymmetric joint.

10 (a) and 10 (b) are explanatory views showing an example of use of a continuous joint shaped steel having a left-right asymmetric joint.

FIG. 11 is an explanatory view showing a conventional method for rolling a vertically asymmetric left-right symmetrical linear steel sheet pile by a hole rolling method.

FIG. 12 is an explanatory diagram showing a rolling method for vertically asymmetrical left-right symmetric linear steel sheet pile, in which a universal rolling method is applied to a part of the conventional hole rolling method.

FIG. 13 is an explanatory view showing a conventional method for rolling a vertically symmetrical left-right asymmetric linear steel sheet pile by a universal rolling method.

FIG. 14 is an explanatory diagram showing a conventional method of rolling a vertical asymmetrical left-right symmetrical linear steel sheet pile by a universal rolling method.

[Explanation of symbols]

 BD: Breakdown mill U: Universal mill E: Edger mill S: Flange bending mill F: Finishing mill 20a, 20b: Horizontal roll of universal mill U 30a, 30b: Vertical roll of universal mill U 21a, 21b: Up and down of edger mill E Rolls 22a, 22b: Upper and lower rolls of flange bending mill S 23a, 23b: Upper and lower rolls of finishing mill F 1a: Web of continuous joint shaped steel of the present invention 1bf: Female joint portion of continuous joint shaped steel of the present invention 1bm : Male joint of continuous joint shaped steel of the present invention 1s: Bent portion of continuous joint shaped steel of the present invention

Claims (10)

[Claims] 1. A female joint and a male joint that are fitted to each other at both widthwise ends of a web having a predetermined thickness and width, and the female joint bends a flange outward in the widthwise direction of the web in a substantially arc shape. Continuous joint shaped steel having a left-right asymmetric joint characterized in that the tip of the claw is bent inward, and the opening width of the claw tip facing the claw is fixed. 2. The continuous joint shape steel with a left-right asymmetric joint according to claim 1, wherein the outer surface of the male joint is a straight line orthogonal to the web. 3. The left-right asymmetric joint according to claim 1, wherein the claws of the male joint are curved inward in a width direction or outward in a width direction of the web in a substantially arcuate shape or bent in a U-shape. Continuous joint shaped steel having. 4. A rough rolling step in which a breakdown mill for forming a left-right asymmetric dogbone-shaped rough shaped material is arranged, and a universal mill for forming a web and a flange to a predetermined thickness and a flange to a left-right asymmetric predetermined width. Continuous joint shaped steel with asymmetric joints by an intermediate rolling process with an edger mill with a variable hole depth mechanism for forming, an intermediate finishing process with a flange bending forming mill, and a finishing rolling process with a finishing mill. In the method of rolling, the width reduction of the asymmetrical flange is performed with the edger mill to obtain a predetermined flange width, and only the female joint side is buckled at the final pass of this width reduction rolling to bend the flange tip to the outside of the flange. To form a substantially H-shaped intermediate rolled material with a large tilt angle only at the flange tip,
Next, the hole type on the female joint side is the stopper part at the end in the width direction,
By the upper and lower horizontal rolls of the flange bending mill having a curved portion formed of a region for shaping the flange tip and a region for bending the flange, while restraining the end face of the flange tip on the female joint side of the intermediate rolled material. After shaping the tip of the flange into a predetermined shape and bending the flange, the spacing between the upper and lower horizontal rolls is adjusted by the finishing mill to shape the web to a predetermined thickness and the flange portion on the female joint side is adjusted to a predetermined value. A rolling method for a continuous joint shaped steel having a left-right asymmetric joint, characterized in that it is curved into a claw shape and the opening width of the claw tip on the female joint side is finished to be substantially constant. 5. The flange width of the male joint portion is balanced with the stretching that occurs when the female joint portion is bend-formed without bending the flange on the male joint side of the intermediate rolled material by a flange bending forming mill and a finishing mill. The rolling method for a continuous joint shaped steel having a left-right asymmetric joint according to claim 4, wherein the rolling is performed by rolling reduction or flange thickness reduction. 6. The male joint side flange of the intermediate rolled material is bent inward in the width direction or outside in the width direction of the web in a substantially arc shape or in a U-shape by the upper and lower horizontal rolls of the flange bending mill. The rolling method for a continuous joint shape steel having a left-right asymmetric joint according to claim 4, wherein the flange portion on the male joint side is curved or bent into a predetermined claw shape with a finishing mill. 7. The side surface of the horizontal roll of the horizontal mill of the universal mill in the intermediate rolling step on the female joint side is formed in a taper or a curve whose width becomes wider toward the axial center of the roll at a predetermined increase rate, and the tip end of the flange is formed. The outer diameter of the rolling section is further increased in the rolling section, and the vertical rolls on the female joint side of the universal mill in the intermediate rolling process are tapered so that the flange tip portions on both axial sides are smaller than the central portion. Alternatively, the continuous shape having the left-right asymmetric joint according to claim 4, 5 or 6 is characterized in that the outer end of the flange on the female joint side is bent by rolling with a horizontal roll and a vertical roll having a curved outer shape. Rolling method for joint shaped steel. 8. A taper or a curve in which the body width of a horizontal roll of a horizontal roll of a universal mill in an intermediate rolling process becomes wider toward the axial center of the roll, and only a portion for rolling the flange tip end has a constant body width. 7. The left and right asymmetric joint according to claim 4, wherein the horizontal roll and the vertical roll on the female joint side having a flat flange pressure lower surface are used for rolling. Rolling method for continuous joint shaped steel. 9. In the intermediate rolling step, after the outer surface of the flange other than the flange tip portion on the female joint side is water-cooled, the flange tip portion on the female joint side is bent in the final pass of the flange width rolling by the edger mill in the intermediate rolling step. The method for rolling a continuous joint shaped steel having a left-right asymmetric joint according to claim 4, 5, 6, 7 or 8. 10. A hole type on a female joint side of upper and lower horizontal rolls of a flange bending mill having a curved portion formed by shaping a flange tip portion and a bending portion of a flange, and a female joint side of an intermediate rolled material. The wedge-shaped vertical roll for restraining the end surface of the flange tip end portion of the above-mentioned, the flange tip end portion on the female joint side is shaped into a predetermined shape and the flange is curved. 8. A rolling method of a continuous joint shaped steel having a left-right asymmetric joint according to 8 or 9.