JPH082441B2 - Straight section steel having continuous joint and method for manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention has a continuous joint and both sides (left and right).
Also, the present invention relates to a linear shaped steel having front and back (upper and lower) symmetry, and a method for roll-forming it.

(Prior Art) In recent years, deepening of depth and construction in urban areas have become mainstream in the active development trend of underground space. In the steel sheet pile driving work done in the densely populated area in the urban area, the vibro hammer and other driving machines that were used before cannot be used to prevent vibration and noise. Therefore, there is a strong demand for joint fitting property that enables steel sheet piles lifted by a crane or the like to smoothly fit into each other's joints without using any means such as driving. That is, regarding the steel sheet pile product, which is a basic member of the above-mentioned steel box-type steel sheet pile, it is an important subject to improve the fitting property of the joint with an emphasis on workability and to provide a product series having a wide range of sectional performance. Especially when constructing a deep underground wall,
Since the earth pressure is small near the ground, the steel sheet pile web thickness Tw may be small, but when used inside the ground where the earth pressure increases, it is necessary to increase the web thickness Tw to increase the rigidity strength of the box-type steel sheet pile. . In this case, the joint thickness T _F of the joint portion is required to be increased as the web thickness Tw increases, if necessary. At the time of construction, relatively short sheet piles having different thicknesses are sequentially joined in the longitudinal direction at the construction site and driven in, and laid continuously in the longitudinal direction.

As a general manufacturing method of the continuous joint shape steel, there is a conventional so-called straight steel sheet pile caliber rolling method shown in FIG. In the figure, the rough billet BB is a material produced in the slab or foundry, and this material BB is
From K1 to K1 in order to obtain a product, but since this method is a rolling process mainly based on the grinding action by the side walls of the upper and lower rolls, the form of each of the above-mentioned hole types is a closed hole type (Closed Pas
s) becomes an integral component of the pore series. For this reason, the amount of roll refurbishment due to hole-type wear is large, the roll unit consumption is high, and a large amount of rolling oil and roll cooling water are necessary.If this is insufficient, the joint shape of the product becomes unstable. Therefore, the rolling work is extremely difficult. Further, since the number of hole types is large, a long roll body length is required, and it is difficult to manufacture a wide straight steel sheet pile having a large effective width W.

As a solution to this problem, there is a so-called universal rolling method disclosed in Japanese Patent Publication No. 47-47784, which is a rolling method for removing a molding defect by directly applying a reduction to a material forming a joint. A typical example of this universal rolling method is shown in FIG.
By performing universal rolling at 1, 2, and 3, it is possible to manufacture from rectangular billet material SL. See also Sho 58
-38241 gazette, by adopting the finishing universal rolling method to the finishing hole type K1 as well, by regulating the hole width of the left and right joints with the vertical rolls fitted in the left and right joint parts, the hole width of the joint The means for suppressing the variation of is also known. However, even with this method, the upper and lower horizontal rolls need 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 was changed to a product shape that facilitates rolling, the so-called universal rolling equipment for H-section steel was used, and it was improved so that it could be rolled by means similar to the rolling method for H-section steel. There is a means. The technology described in Japanese Patent Publication No. 55-11921 shown in FIG. 10 and the technology described in Japanese Patent Publication No. Sho 55-1913 shown in FIG. 11 are examples, and in the case of rolling in the closed hole type described above. Although the problem has been solved, it is intended for the production of linear steel sheet piles of a specific size, and the production of different web thicknesses and the formation of flange widths according to various web thicknesses are within a very narrow range due to molding restrictions. There was a problem that there was no choice but to limit it to.

On the other hand, various shapes have been proposed for a joint of a straight steel sheet pile, but an arcuate female joint (claw) to which the present invention is applied.
A typical male joint that fits in is a Y-type or T-type as shown in FIGS. 7 (b) and 7 (c).
However, in this type of claw shape, when the fitted female and male claws are pulled from each other, there is a risk that their tips will be deformed and come off.

(Problems to be Solved by the Invention) The present invention is to improve the above-described male joint, and to provide a straight shaped steel having a continuous connection type joint having excellent fitting tensile strength, and When manufacturing a shaped steel by rolling, the joint part shape defect, bending during rolling, without lowering the roll unit, etc., the web thickness is formed into a desired size and a flange with a constant width is formed, By forming a male joint in which the flange is bent, it is possible to obtain a continuous joint having excellent fitting tensile strength, and a straight shaped steel having a continuous joint having excellent fitting performance. It is an object of the present invention to provide a method for rolling forming by utilizing the existing H-section steel universal rolling machine train as much as possible and minimizing new installation and modification of rolls and guides.

(Means for Solving the Problems) In order to achieve the above object, the present invention has the following structure. That is, (1) front and back symmetrical male claws curved toward the center of the web are formed at both widthwise ends of a web having a constant effective width and a predetermined thickness according to the use site. Is a straight-section steel having a continuous joint characterized in that the length (l) of one side arc is 1 to 5 times the thickness t _f of the claw, and is formed on both end sides in the web width direction. The male claw may be configured to form an arc around the web. Further, (2) the slab material is formed into a dogbone-shaped rough shaped material in a rough rolling step in which a breakdown mill is arranged, The rough shaped material is subjected to intermediate rolling with a universal mill and an edger mill to make the inner width of the universal mill and the web part constant, and the web and the flange have a predetermined thickness, and the flange width reduction is performed while restraining the web with the edger mill. Optimum flange width Then, the left and right flanges are bent inward and arcuately while pressing the web portion with a horizontal roll of a finishing mill, and a method for producing a straight shaped steel having a continuous joint.

(Operation / Example) Hereinafter, an operation and an example of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the straight section steel having the continuous connection type joint of the present invention has a constant effective width W (the length between the claw tips on both sides) of the web 1a within the series as shown in FIG. tw has a predetermined size (variable thickness) corresponding to the part to be used. That is, this makes it possible to continuously connect the shaped steels to each other in the vertical direction, and also to maintain the strength corresponding to the installation location. At both ends in the web width direction, as shown in a model in FIG. 2, a male joint (claw) is bent on the front side (X) and the back side (Y) with a predetermined curvature r to the center side (inner side) of the web. ) 1b and 1b 'are provided. The male claws 1b and 1b 'are symmetrical with respect to the front (X) and the back (Y), and may be a continuous arc centering on the web. When the pawls 1b and 1b 'molded by such inward bending are fitted into the arcuate female joint, and when the pawls 1b and 1b' are pulled together, the tips of the pawls 1b and 1b 'are caught in the inner circumference of the female joint, which results in fitting. The tensile strength can be remarkably improved. The thickness t _F of the claws 1b and 1b ′ may be selected in the range of 1 / t _F = 1 to 5 in relation to the length l of the half arc of the claw (front or back claw). If the l / t _F is less than 1, it is difficult to deform, while if it exceeds 5, the strength is weakened, which is not preferable.

The linear shaped steel (hereinafter referred to as the linear shaped steel) having the above-described continuous joint of the present invention is roll-formed as follows.

FIG. 3 shows an example of a rolling forming method when the present invention is applied to the production of vertically and horizontally symmetrical straight shaped steel, and FIG. 4 shows an example of a rolling step for carrying out the method of the present invention.

In the rough rolling step of the present invention, the breakdown mill BD
The upper and lower horizontal rolls perform edging multiple times using a thin-walled slab having a rectangular cross section or a dogbone-shaped steel slab as a raw material to process it into a dogbone-shaped rough shaped material. The rough rolling step in the present invention is the same step as the conventionally well-known rough shaping of a shaped steel having a flange such as an H-shaped steel. Therefore, its detailed description is omitted.

Next, in the intermediate rolling step of the present invention, a universal mill U
And an edger mill E are arranged, and the rough shape material is formed into a universal mill U by a hole type KAL.2, which has a predetermined web thickness and flange thickness in the series, and intermediate rolling of a substantially H-shaped cross section having a constant web width. Roll molding is performed on the material 11a. Horizontal rolls 20 that make up Universal Mill U here
A and 20b are rolls formed so that the surface that presses the web surface of the intermediate rolled material 11a is flat and that the side surface that abuts the inner surface of the flange has an outer inclination angle α (approximately 3 to 10 °). The inner surface of the flange with the horizontal roll 20
The openings of a and 20b are adjusted to obtain a desired web thickness. That is, the horizontal rolls 20a and 20b have the same profile as the horizontal roll in the conventional universal mill for H-shaped steel rolling, and can be shared or used. On the other hand, vertical roll
As the rolls 30a and 30b, rolls that press the flange surface of the intermediate rolled material 11a and whose roll peripheral surfaces are formed to be substantially flat (hereinafter referred to as flat vertical rolls) are used. Similarly, the flat vertical rolls 30a and 30b are used. Also, a flat vertical roll used in a conventional universal mill for H-shaped steel rolling can be used. That is, by using the flat vertical rolls 30a, 30b together with the horizontal rollers 20a, 20b, the wall thickness of the joint portion of the straight-section steel is formed to a predetermined thickness, and the product shape is rational in terms of joint performance. It is economical with few wasted parts, and it is possible to reduce the web deviation of the intermediate rolled material 11a and the thickness difference between the upper and lower flanges.

Next, the intermediate rolled material 11a rolled by the universal mill U is subjected to its flange (f) by the hole type KAL.2E of the edger mill E arranged in pairs with the universal mill U.
Intermediate-rolled material 11 whose edges are shaped to have a specified web thickness
formed in b. Horizontal roll of this Edger Mill E 21
a and 21b are the same as the horizontal roll shape in the conventional edger roll for rolling H-section steel, and do not positively reduce the web surface of the intermediate rolled material 11b, but restrain the both ends of the web surface. Simultaneous reduction of the tip of the flange (f) is performed. At this time, the flange (f) may be inclined at a right angle or slightly outward (β = about 3 to 10 °). In this step, the web can be accurately held at the center position of the flange while performing such flange forming.

In this example, one universal mill U and one edger mill E are arranged to form a pair, but these may be knitted into a group of a plurality of pairs of rolling mills as needed.

The edger mill E is, as shown in FIG. 5, an edger mill in which the hole type leg length lk is variable online.
Can replace Ec. That is, the intermediate rolled material 11a rolled by the universal mill U is the hole type KA of the leg length variable edger mill Ec arranged in a pair with the universal mill U.
The flange (f) end portion is shaped by L.3E, and is formed into the intermediate rolled material 11b having a predetermined flange width dimension according to the web thickness. This leg long diameter variable edger mill Ec
Is mainly composed of upper and lower web restraint rolls 23a and 23b, and edging rolls 40a and 40b that can be rotated in synchronization with the rolls and can adjust the width between the rolls, and are positive for the web surface of the intermediate rolled material 11b. However, the restraint of both ends of the web surface and the reduction of the flange tip are performed at the same time, and the flange according to the thickness of the web, that is, the flange piece width (leg length) lk is edging controlled to an appropriate dimension, and
The web can be accurately held at the central position of the flange. Specific examples of this leg length variable edger mill Ec are disclosed in JP-A-62-77107 or JP-A-62-77101, and these can be used in the present invention.

Intermediate rolled material 11b having a substantially H-shaped cross section which is symmetrical by being rolled by the universal mill U and the edger mill E (Ec).
Is finished into a final product 12 by a finish rolling mill F. Hole type KA of upper and lower horizontal rolls 22a and 22b of finish rolling mill F
L.1 is provided with a body portion that presses the web portion, and a finishing hole die R that is formed by bending the flange (f) inward at both end portions thereof. That is, the finishing hole die R is composed of a curved forming portion R ₁ that bends the flange (f) inward and a stopper portion R ₂ that holds the tip of the flange and facilitates bending work. It is possible to manufacture the product 12 having the same width W in the series having the nail.

The straight section steel having the continuous joint of the present invention manufactured as described above is continuously used in a box-type sheet pile or a circular cell as shown in FIGS. 6 (a), (b) and (c). can do. That is, FIG. 6 (a) is a box-shaped sheet pile in which arc-shaped joints (female joints) 6 are vertically arranged in the same manner as a box-shaped sheet pile in which the shaped steel (male joint) 1 of the present invention is welded up and down with H-shaped steel 5. (B) is an example in which the joint 1 of the present invention and the arcuate female joint 6 are vertically combined. Further, FIG. 3C is an example of a circular cell in which the male joint member 1 of the present invention and the female joint member 6 are continuously engaged in a circular shape. And these are constructed by using straight shaped steels having the same effective web width W.

As described above, by using the inward bending type male joint of the present invention, the joint fitting tensile strength is extremely increased. Each joint shape shown in FIGS. 7 (a), (b), and (c), that is,
(A) engages the male joint 1 of the present invention with the arcuate female joint 6,
(B) is a conventional Y-type male joint 7 and (c) is a conventional T-type male joint 8 engaged with each other, and the strength when these engaging joints are pulled in the direction of arrow S ( The fitting tensile strength) was measured. The measurement results are shown in Table 1 (measured value ton / m
= Converted value per 1 m of wall length).

From the results of the above invention, it is understood that the joint of the present invention type [Fig. 7 (a)] is extremely excellent. That is, when a tensile force is applied in the direction of arrow S, the end of each joint is deformed in the direction of arrow P to form the shape shown by the broken line, and when the limit value (measured value in Table 1) or more is reached, -The female joint is disengaged.
In the fitting of joints having the same thickness and shape, the tensile strength is approximately proportional to the "engagement depth" (male joint outer width g-female joint opening width k). In the joint of the present invention [Fig. 7 (a)], g is increased by the tensile deformation of the female joint, whereas in the conventional type [Figs. 7 (b) and (c)], g is decreased. Therefore, there is a large difference as shown in Table 1.
Further, the slip resistance at the contact surface in the joint also has an effect on the tensile strength, and the type of the present invention makes it difficult to slip even if the joint shape is deformed by the tensile force by contacting the inner surface of the female joint with the sharp edge of the male toe. On the other hand, in the conventional type, as the joint is deformed by the tensile force, all of the contact surfaces are smooth and slippery, which is one of the reasons why the strength cannot be increased.

(Effects of the Invention) The continuous joint shape steel of the present invention has extremely high fitting strength and fitting tensile strength, and when manufacturing this, significant changes must be made to the existing H-section steel universal rolling mill train. Without having to bring it, a continuous joint shaped steel having multiple sizes of web thickness Tw and joint thickness T _F of a male joint can be manufactured into an economically desired size according to a construction project without bringing the same roll set. , The required number of rolling rolls and their accessories is drastically reduced, and the roll unit is improved,
Since the number of roll changes is reduced, the operating rate is improved and the number of change workers is reduced. Furthermore, the size of the materials used can be aggregated, which is a great advantage in production. In addition, since it is possible to efficiently manufacture high quality continuous joint shape steels with stable joint shape and excellent workability even in small lots, it is possible to quickly and accurately respond to the needs of the current diversifying market. it can.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of the continuous joint shaped steel of the present invention, FIG. 2 is a view showing the joint shape of the shaped steel of the present invention, and FIG. 3 is a rolling process of the shaped steel of the present invention by each rolling mill. FIG. 4 is an explanatory view showing the order of the steps, FIG. 5 is a view showing another example of the edger mill in the step of FIG. 4, and FIGS. 6 (a), (b) and (c) are Explanatory drawing which shows the usage example which formed the box-shaped steel sheet pile and the circular cell in the upper and lower left-right symmetrical continuous joint type steel manufactured by this invention, FIG.7 (a), (b), (c) is this invention and the conventional. Fig. 8 is a diagram showing a fitting tension state of a joint according to the method, Fig. 8 is an explanatory diagram showing a rolling method of a vertical asymmetrical left-right symmetrical type straight type steel sheet pile by a conventional hole rolling method, and Fig. 9 is a conventional hole rolling method. Explanatory drawing showing the rolling method of the vertical asymmetric left-right symmetrical type straight-line steel sheet pile partially applied with the universal rolling method, Fig. 10 Explanatory view showing a rolling method of vertically symmetrical asymmetrical type linear steel sheet pile by a conventional universal rolling method, Fig. 11 is an explanatory view showing a rolling method Asymmetric symmetric type linear steel sheet pile according to a conventional universal rolling method. BD: Breakdown mill U: Universal mill E: Edger mill F: Finishing mill 1: Continuous joint shaped steel 1b: Joint (claws) 6-8: Conventional joint 11a, 11b: Intermediate rolled material 12: Final product 20a, 20b : Horizontal rolls of universal mill U 30a, 30b: Vertical rolls of universal mill U 21a, 21b: Divided horizontal rolls of edger mill E 22a, 22b: Horizontal rolls of finishing mill F 23a, 23b: Web restraint rolls of variable leg length 40a, 40b: Edging roll of variable leg length edger mill

Claims (2)

[Claims] 1. A front and back symmetrical male claw that curves toward the center of the web is formed on both widthwise ends of a web having a constant effective width and a predetermined thickness according to the site of use, and the male claw is formed. The straight-section steel having a continuous joint, wherein the length (l) of the one side arc is 1 to 5 times the claw thickness t _f . 2. A slab material is made into a dogbone-shaped rough shaped material in a rough rolling step in which a breakdown mill is arranged, and the rough shaped material is intermediately rolled by a universal mill and an edger mill,
The universal mill keeps the inner width of the web constant, and the web and the flange have a predetermined thickness. The edger mill restrains the web to reduce the width of the flange to the optimum flange width, and then the horizontal roll of the finishing mill. A method for manufacturing a straight shaped steel having a continuous joint, wherein the left and right flanges are bent inward and in an arc shape while pressing the web portion.