WO1997012701A1

WO1997012701A1 - Method of correcting u-shaped steel sheet pile

Info

Publication number: WO1997012701A1
Application number: PCT/JP1996/002680
Authority: WO
Inventors: Toru Yuasa; Hiroshi Shikano
Original assignee: Sumitomo Metal Industries, Ltd.
Priority date: 1995-09-29
Filing date: 1996-09-18
Publication date: 1997-04-10
Also published as: DE69630670D1; KR980700137A; KR100480243B1; CN1073893C; EP1338351A1; CN1159120C; EP1338351B1; DE69630670T2; AU692404B2; EP0795364B1; EP0795364A1; CN1313152A; CN1165489A; DE69638361D1; TW346422B; EP0795364A4; AU7000396A

Abstract

A method for efficiently correcting the bend and flexure of a U-shaped steel sheet pile, especially having an arm. To eliminate the bend of such a steel sheet pile, the outer side of one flange of the steel sheet pile and the inner side of the other are pressed at the same time. To eliminate the flexure of such a steel sheet pile, correction rollers are used for restraining a web, flanges and arms of the steel sheet pile from the upper and lower sides.

Description

Specification

U-shaped sheet pile straightening method

Technical field

The present invention relates to a method for correcting a U-shaped steel sheet pile having an arm between a flange portion and a joint portion among U-shaped sheet piles used for civil engineering and construction, for example. Background art

Conventionally, steel sheet piles manufactured by hot rolling and cut to a predetermined length are warped in the length direction due to internal stress as cooling proceeds, and shape defects such as bending occur ₍ here, `` The term `` warpage '' refers to a large bend in the direction perpendicular to the sheet pile wall 2 of the U-shaped sheet pile 1 as shown by the symbol C in Fig. 1, and the end bend. Means a large bend and an end bend in the direction parallel to the sheet pile wall 2 of the U-shaped steel sheet pile 1 _{(in the} JISA 5528 standard, the bend of a U-shaped sheet pile is 10 m or less in length. On the other hand, the total length X is 0.12% or less, and for steel sheet piles exceeding 10 m, the total length is 1 (10 m) x 0.10 + 12 mm or less. For steel sheet piles below, total length X 0.25% or less, and for those exceeding 10m, (full length-10m) X 0.20% + 25mm or less. Be

The correction of such a shape defect is generally performed by a roller straightening machine. <This roller straightening machine arranges, for example, three rollers below the four upper openings in a staggered manner with respect to the upper rollers. Because of this, the front and rear ends of the steel sheet pile cannot exhibit sufficient straightening effects, especially the warpage of the front and rear ends. It is common to correct.

Fig. 3 illustrates the straightening operation by the press straightener when the U-shaped sheet pile 1 to be straightened is bent. In the case of the illustrated example, a pressing rod (not shown) for applying a pressing force in the direction of the arrow through the jig 5 is provided, and on the opposite side, as shown in the drawing, a U-shaped steel sheet pile as a material to be corrected Two jigs 6 and 8 that support one flange outer surface 4 of 1 are installed to restrain the movement of the material to be corrected. However, in the case of u-shaped steel sheet piles, which have high rigidity to bending in the left-right direction, as shown in Fig. 4 (a) and Fig. 4 (b), the flange outer surface 4 on one side (see Fig. 3) ) Is pressed by a press without bending, and the width of the material to be corrected is narrowed so that the reference width „shown in Fig. 4 (a) becomes the width W shown by the dotted line. In addition to deforming the cross-sectional shape, there were problems such as locally forming a dent D in the pressed flange as shown in Fig. 4 (b). This was particularly noticeable on a platform where straightening of a U-shaped steel sheet pile with an arm between the flange and the joint (claw) was to be performed.

On the other hand, some methods have been already proposed for correcting the warpage of U-shaped steel sheet piles, and even in the past, for example, Japanese Patent Application Laid-Open No. 61-63316 discloses a U-shaped steel sheet pile. In a pair of upper and lower straightening rollers having a straightening portion for holding a web portion and a flange portion, a joint restraint portion for restraining a joint portion of a U-shaped steel sheet pile is provided adjacent to both sides of the straightening portion of the upper straightening roller. It has been proposed. A similar proposal is also made in Japanese Patent Application Laid-Open No. 55-70418.

For example, as shown in FIG. 5, a straightening roller 10 for a U-shaped steel sheet pile includes straightening rollers 10a, 10b and a low-roller, which are separated from the outer portion of a rib 12, a flange 14, and a joint 16 respectively. It is designed so that it can be corrected by bending correction that repeats up and down, left and right bending while constrained by the la 18, and that the dimensions of the entire width of the product can be adjusted by rollers 18 that constrain the outside of the joint 16. As described above, since the bending and straightening are performed while restraining the tube portion and the flange portion, the sectional shape of the product is straightened without being deformed.

However, as shown in Fig. 6, in the case of a U-shaped steel sheet pile having an arm portion 19 between the joint portion 16 and the flange portion 14, when straightening is repeatedly performed by bending, the flange portion eventually ends. It was found that the angle of the joint was different from the intended product cross section. Disclosure of the invention

A first object of the present invention is to provide a novel straightening method and a jig used for the same, which solve the drawbacks of the conventional method for correcting the "bending" of the U-shaped steel sheet pile in the left-right direction and the jig used for straightening. It is to be. A specific object of the present invention is to provide a steel sheet pile having high bending stiffness in the lateral direction, such as a U-shaped steel sheet pile having an arm portion between a flange portion and a joint portion (claw portion). of

An object of the present invention is to provide a straightening method capable of efficiently correcting "bending" and a jig used for the straightening method.

A second object of the present invention is to provide a roller straightening method capable of straightening a U-shaped sheet pile having an arm portion without deforming a cross-sectional shape when correcting the roller.

In order to easily press-bend the bending of a steel sheet pile having high bending rigidity in the lateral direction of the product, the present inventors have not only pressed the surface of one flange, but also pressed the other flange. Based on the finding that it is effective to simultaneously press the inner surface in the same direction, the present invention was completed:

In addition, the present inventors conducted various studies on the problem that the angle between the flange portion and the joint portion differs from the target angle when correcting the warpage of the U-shaped steel sheet pile having the arm portion with the roller. It is not sufficient to simply restrict the entire web section and flange section only in cross-section, and it is not sufficient to provide cross-section restriction including the arm section, and preferably, the web section and the flange section. The present invention was completed by finding that such a correction of the arm portion can be performed with high accuracy by integrating the rollers for restraining the flange portion and the arm portion with both the upper and lower portions. Here, the present invention relates to a method for correcting a lateral bending generated in a hot rolling process of a U-shaped steel sheet pile, wherein the outer face of one side flange of the steel sheet pile is pressed while the other flange is pressed. A method of straightening steel sheet piles, characterized by pressing the inner surface of the jaws,

From another aspect, the present invention provides a first jig having a surface for pressing an outer surface of a flange on one side of a U-shaped steel sheet pile, and further connected to the first jig and the other jig. A straightening jig for U-shaped steel sheet pile, comprising a combination of both a second jig having a surface for pressing the inner surface of the flange.

According to a preferred aspect of the present invention, a second jig for pressing the inner surface of the flange can be attached to and detached from a first jig having a surface for pressing the outer surface of the flange of the U-shaped steel sheet pile. A functional fitting portion may be provided at a connecting portion between the two jigs.

According to yet another preferred embodiment, the U-shaped sheet pile has a surface for pressing the outer surface of the flange. An adjustment mechanism capable of changing the relative position in the product width direction of the second jig that presses the inner surface of the flange with respect to the first jig may be provided at a connection portion between the two jigs.

From yet another aspect, the present invention relates to a method for correcting a roller of a U-shaped steel sheet pile, comprising a rib portion, a flange portion, and a joint portion, and having an arm portion between the joint portion and the flange portion. A straightening roller for restraining the arm from above and below, and preferably a straightening roller in which the upper and lower rollers are integrated are used, in addition to the arm and flange. Roller straightening method for U-shaped steel sheet pile.

According to a preferred embodiment of the present invention, when constraining the arm between the flange portion and the joint portion, a straightening roller that constrains from an up-down direction at an angle different from the product cross section may be used:

As described above, according to the roller straightening method according to the present invention, the straightening roller for straightening the U-shaped steel sheet having the arm by repeatedly bending the upper and lower sides and the left and right sides thereof is provided on the upper side of the U-shaped steel sheet pile. It consists of a constraining roller and a lower constraining roller, in which the upper and lower rollers are arranged in a staggered manner. BRIEF DESCRIPTION OF THE FIGURES

Figure 1 is a schematic illustration of the warpage of steel sheet piles.

FIG. 2 is a schematic explanatory view of bending of a sheet pile.

FIG. 3 is a schematic explanatory view of a method for straightening steel sheet pile bending press.

Fig. 4 (a) is an illustration of the width reduction when straightening steel sheet piles, and Fig. 4 (b) is an illustration of the local deformation of the flange:

FIG. 5 is an explanatory diagram of a conventional roller straightening method for a U-shaped steel sheet pile. _C FIG. 6 is an explanatory diagram of a conventional roller straightening method for a U-shaped steel sheet pile having an arm portion.

FIG. 7 is an explanatory diagram of the press straightening method according to the present invention.

FIG. 8 is an explanatory diagram of an example of the press straightening jig of the present invention.

FIG. 9 is an explanatory view of another embodiment of the press straightening jig of the present invention.

FIG. 10 is an explanatory diagram of an example of an arrangement of a U-shaped steel sheet pile having an arm and a straightening roller according to the present invention. 0 FIGS. 11 (a) and 11 (b) are explanatory views of a vertical straightening roller according to the present invention of a U-shaped steel sheet pile having an arm portion.

FIG. 12 is an explanatory view of a cross-sectional shape of a U-shaped steel sheet pile when straightening the upper roller.

Fig. 13 is an explanatory diagram of the cross-sectional shape of the U-shaped sheet pile when the lower roller is straightened.

Fig. 14 is a graph showing the relationship between the angle of the flange and the arm in the longitudinal direction .: Fig. 14 is a graph showing the total width variation in the longitudinal direction.

Fig. 16 is a graph showing the relationship between the angle of the flange portion and the arm portion in the longitudinal direction. Fig. 17 is a graph showing the total width variation in the longitudinal direction. Best form for

According to the straightening method of the present invention, the pressing force indicated by the arrow in FIG.

In order to simultaneously press the outer surface 22 of the flange 21 on one side of the U-shaped sheet pile 20 and the inner surface 23 of the other flange 21 in the same direction, an external force is applied only to one side of the flanges 21 and 21. Therefore, the product does not concentrate, so that the width of the product is not narrowed, and the flanges 21 and 21 do not cause local deformation such as local dents.

At this time, the pressing force for pressing the outer surface 22 of the one-sided flange 21 and the inner surface of the flange 21 are

The pressing force for pressing 23 may be the same or slightly different. Product width fluctuations: To prevent local deformation of the flange, press both sides with the same presser as much as possible. It is preferable to:

In this regard, according to the conventional method, as shown in Fig. 3, in order to apply a pressing force only to the outer surface of the flange on one side of the U-shaped sheet pile 1, pressing is performed as shown in Fig. 4 (b). Local deformation such as local dents will occur in the flange on the receiving side.

FIG. 8 illustrates an example of a jig used in the straightening method according to the present invention. The jig is brought into contact with the outer surface 22 of the flange 21 of the U-shaped steel sheet pile 20 as a material to be straightened and pressed. First jig 24 for fixing, and the inner surface of the other flange 21 across the flange 21

And a second jig 25 for contacting and pressing. Hereinafter, the first jig is simply referred to as jig A, and the second jig is referred to as jig B.

In FIG. 8, the jig A and the jig B are appropriately connected by a connecting portion 26. For example, after the jigs A and B are appropriately fitted, the screw holes provided on the jig B side are provided. Through 27 b, the bolt 28 may be fixed. As a form of this connection, an integral structure may be used, but other than that, simple fitting, connection by a pin and a pin hole, and the like are also conceivable. However, it is preferable that the above-mentioned fitting screw type has a more simple and reliable structure.

After such a configuration, the same press force is applied to the jigs A and B by applying a presser in the direction of the arrow to the press ram head connecting portion 29 provided on the jig A on the base in the illustrated example. The correction method of the present invention is performed by pressing both flange surfaces in addition to the same direction.

The jig A and the jig B are configured so that they can be attached and detached at the connecting part in the illustrated example in order to facilitate handling, but of course, they may be integrated.

Further, in the embodiment (4), instead of connecting the jigs A and B with the connecting portion, a margin is provided at a fitting portion between the two jigs so that the jigs A and B are provided in the width direction of the product. It may be configured such that the relative position between the tool and the jig B can be adjusted. As a result, the press force when simultaneously pressing the outer surface of the flange and the inner surface of the other flange is appropriately distributed according to the dimensional variation (width variation) of the material to be straightened, and local deformation of the material to be rolled is reduced. Bending straightening can be performed efficiently without causing

In such an embodiment, as shown in FIG. 9, the connecting portion 26 between the jig A 24 and the jig B 25 is a kind of a slide type, which can be finely adjusted in the direction of the arrow, and For example, a screw-type fixing mechanism (not shown) may be provided.

In any case, in order to correct the bending of the U-shaped steel sheet pile by the press straightening method according to the present invention, the U-shaped steel sheet pile 20 travels on the transport roller R and comes to a predetermined position as shown in FIG. At first, it is fixed by a jig composed of a combination of jigs A and B, and then a pressing force is applied in the direction shown in the figure. The fixing position of the jig at this time is shown in Fig. 3, for example. In this way, one piece is attached to the press pressing side and two pieces are attached to the support side of the material to be corrected. However, since a specific correction operation may be performed in the same manner as the conventional correction operation, further description is omitted.

Fig. 8 shows an example of a U-shaped steel sheet pile that has an arm between the joint (claw) and the flange. It may be a sheet pile, and it can be implemented only by slightly changing the jig shape according to the product shape. I is the same. In the illustrated example, the U-shaped posture is shown as the posture of the material to be corrected. However, the same applies to the inverted u-shaped posture, and the jig is turned upside down in accordance with the shape of the material to be corrected. You just need to flip it.

Next, a roll straightening method for straightening a U-shaped sheet pile will be described.

FIG. 10 is an explanatory view of the arrangement of a straightening roller for a U-shaped steel sheet pile having an arm as an example of the straightening roller according to the present invention. In the figure, a U-shaped steel arrow having a rib 30, a flange 32, an arm 34, and a joint 35 is provided by upper rollers 36, 36, lower rollers 38, 38, and an outer roller 40. Arms are constrained in addition to ribs and flanges. In the illustrated row, both the upper and lower straightening rollers 36 and 38 are integrally formed so that the web portion 30 and the flange portion 32 can be restrained by the same roller. The angle between the arm part 34 and the flange part 32 is different from that of the final product. It is repeatedly bent and straightened by attaching a taper to the part where the arm part 34 of the rollers 36 and 38 is restrained. May be corrected to the same angle as the product _c

FIGS. U (a) and (b) are schematic views of an example of the straightening roller according to the present invention in such a case. The difference is that the rollers 36 and 38 are provided with a taper having an angle α, respectively, as compared with the field base of FIG.

In any case, 場 The base of the force using the straightening roller that restrains the arm from the vertical direction in addition to the X and flange parts (in particular, Fig. 11 (a), (1)) For this purpose, a straightening roller is used to restrain the arm between the flange and the joint at an angle different from the cross section of the product and from the top and bottom.

In the above illustrated example, the upper and lower rollers 36 and 38 are drawn as if the respective rollers were aligned in the vertical direction. Actually, the upper and lower rollers are staggered. .

Here, the principle on which the roller correction is effectively performed by such restraint will be described as follows.

In other words, repeated bending correction is performed by three-point support using upper and lower rollers arranged in a zigzag pattern, but if the fulcrum is on the lower roller and the power point is on the upper roller, as shown in Fig. 12, When the arm 34 is not restrained, the angle formed by the arm 34 and the flange 32 becomes smaller, that is, the rising angle 0 of the arm 34 becomes larger. o That is, the arm 34 is deformed in the direction of the arrow in the figure. However, when the upper portion 34 is restrained from above and below according to the present invention, the cross-sectional shape of the U-shaped steel sheet pile is maintained without deformation.

When the fulcrum is on the upper roller and the point of force is on the lower roller, as shown in FIG. 13, when the arm 34 is not restrained, the angle between the arm 34 and the flange 36 is As a result, the arm 34 is deformed downward so that the angle Θ increases. That is, the arm 34 is deformed in the direction of the arrow in the figure. However, the cross-sectional shape when the arm 34 is restrained according to the present invention is maintained without deformation.

Therefore, as in the present invention, the arm and the web and the flange are restrained together, preferably from above and below, by the same roll. It can be corrected without impairing the cross-sectional shape of the product as in the case of 3. In particular, by constraining the entire cross-section except for the joints with a roll-hole type, it is possible to effectively correct not only the vertical warpage of the U-shaped sheet pile but also the slight lateral bending.

As described above, according to the present invention, a U-shaped steel sheet pile having an arm with high rigidity against bending and warping as compared with a U-shaped steel sheet pile having no arm can also be subjected to the press straightening or the mouth straightening. This makes it possible to easily remove the slight bending and vertical warpage, while maintaining a constant angle of the arm. Example

Next, working effects of the present invention will be specifically described with reference to examples.

(Example 1)

The results of applying the press straightening method according to the present invention to a U-shaped steel sheet pile having an arm portion between a joint portion and a flange portion will be exemplified below.

The dimensions of the material to be straightened are as shown in Table 1. Press straightening uses a press machine with a horizontal hydraulic cylinder, and the jig spacing on the supporting side (equivalent to the distance between jigs 6 and 8 in Fig. 3). ) Was 1.2 m.

As a straightening method, in order to remove the left and right bends over the entire length of the material to be straightened, the material to be straightened is intermittently fed in the longitudinal direction at a pitch of 1.2 m every time the press is straightened. The method of repeating the work was adopted. As a jig used in the press straightening method according to the present invention, a combination of two jigs (jig A and jig B) as shown in FIG. 8 was employed. Correction by the conventional method, which corrects left and right bends with jig A alone, was also performed.

Table 2 shows a comparison of the product left and right bending levels after the straightening method of the present invention and the conventional straightening method. As can be seen from the results in this table, the bending was significantly reduced before and after the straightening according to the press straightening method of the present invention, whereas the bending level was substantially reduced before and after straightening with the conventional press straightening method. However, conversely, the product width is defective. Defects have occurred due to local deformation of the flange.

table 1

(Note) Number of products: 20 each. Table 2 Straightening method of the present invention Conventional straightening method

Arrow bending average value 20 mm 18 mm

Positive standard deviation 2.1 mm 1.8 mm

Previous Other quality No problem No problem

Bending average value 7 mm 16 mm

Positive standard deviation (σ) 0.4 ram 2.0

After Other quality No particular problem (Example 2)

The results of applying the press straightening method according to the present invention to a general U-shaped steel sheet pile having no arm between the joint and the flange will be described below.

The dimensions of the material to be straightened are as shown in Table 3. In this example, the right and left bends that could not be completely removed by the roller straightening in the previous process were straightened at both ends (approximately 1.2 m each) of the material to be straightened. The press straightening of the present invention was carried out in order to perform the same, but the other conditions were the same as in Example 1.

Table 4 shows a comparison of the product left and right bending levels after straightening by the straightening method of the present invention and the conventional straightening method. From the results shown in this table, according to the press straightening method of the present invention, compared to the conventional press straightening method, the bending before and after straightening is greatly reduced, and the straightening is realized in a short time. According to the straightening method of the present invention, it is understood that the straightening can be efficiently performed.

Table 3

(Note) Number of products: 20 each. Table 4 Correction method of the present invention Conventional correction method

Arrow bend average value 3 mm 2 mm

Positive standard deviation (σ) 0.5 ram 0.4 4 ■

Previous Other quality No problem No problem

Arrow bend average value 0.5 mm 1.0 mm

Positive standard deviation (σ) 0.1 1 0.4 mm

After Other quality No problem No problem

Correction time 5 minutes 10 minutes (Example 3)

In this example, the U-shaped dwarf method according to the present invention was applied to a U-shaped steel sheet pile having an arm portion between a joint portion and a flange portion.

The dimensions of the material to be corrected are as shown in Table 5.

Table 5

(Note) Number of products: 20 in each case As a comparative example, the case where the conventional straightening roller, in which only the web part and the flange part shown in Fig. 6 are respectively bound to 别 pieces, is used as shown in Fig. 10 In the case where the straightening roller according to the present invention, in which the web portion and the flange portion are simultaneously restrained by the same (integral type) roller and the arm portion is restrained by the same upper and lower rollers, the straightening roller according to the present invention is used. Was examined for its cross-sectional shape.

When the straightening roller according to the present invention was used, the warpage in the longitudinal direction could be completely eliminated, and the cross-sectional shape and width of the arm portion were not substantially changed.

In the upper roller according to the present invention, when the web, the flange, and the arm are respectively restrained by separate rollers, the boundary between the web and the flange, and the boundary between the flange and the arm. Such a non-integrated roller did not provide a sufficient warp correction effect because the roller could not restrain the part.

Fig. 14 shows the relationship between the angle of the flange and the arm in the longitudinal direction, and Fig. 15 shows the relationship of the total width variation in the longitudinal direction.

FIG. 14 is a graph showing the length in the longitudinal direction of the U-shaped steel sheet pile (the amount of change d e g r e e before and after correction of the angle of the arm with respect to L J). In the figure, in the case of the present invention shown by ·, it is almost constant irrespective of the distance in the longitudinal direction, and in the conventional example shown by 〇, it can be seen that the arm is deformed downward. Conventional example depending on the reduction amount and reduction pattern during straightening (〇)

«Τ ΤΓ"-<rtL, + Η Ρϊι Ι ハ Although there was a difference between the upward and downward deformation directions, almost the same results were obtained. FIG. 15 is a graph comparing the length (L o) of the U-shaped sheet pile in the longitudinal direction (L o) with respect to the variation (Δ ^) before and after the correction of the dimension of the entire width (W o). In the present invention example, 〇 is a comparative example, and in this case, there is no substantial variation in the present invention example.

As described above, according to the present invention, as compared with the conventional method, the angle between the flange portion and the arm portion, and the dimension of the entire width hardly fluctuate, and good results are obtained.

(Example 4)

In this example, in the same manner as in Example 3, the case where the straightening roller according to the present invention shown in FIG. 10 is used, and the case where the roller shown in FIG. 11 is tapered (taper angle 3 °). Then, it was investigated whether there was a difference in the cross-sectional shape after the straightening.

In each case, the warpage in the longitudinal direction was effectively removed.

Figure 16 shows the change in the length in the longitudinal direction () and the amount of change before and after the correction of the angle of the arm. Figure 17 shows the relationship between the length in the longitudinal direction () and the change in the total width (Wo) before and after the correction. Each is shown by a graph. In the figure, when Hata does not have a taper, "" indicates a case where a tapered roller is used. Depending on the amount of reduction and the pattern of reduction at the time of straightening, deformation of the arm when no taper is provided (handle) Although the direction was upward and downward, the same result was obtained.

From these results, it can be seen that the provision of the taper reduces both the angle variation of the arm and the variation of the overall width. Industrial applicability

As is clear from the above examples, the use of the press dwarfing method and the straightening jig according to the present invention makes it possible to straighten a U-shaped sheet pile in a short time and efficiently, and particularly to a U-shaped steel sheet having an arm. Even for steel sheet piles such as sheet piles that have a cross-sectional shape with large bending rigidity in the lateral direction, press dwarfing can be performed effectively without causing product defects, and their industrial utility value is extremely large.

Further, in the roller straightening of a U-shaped steel sheet pile having an arm using the straightening roller of the present invention, the roller can be straightened without deforming the cross-sectional shape (full width, angle between the flange and the arm). .

Claims

The scope of the claims

1.In the method of correcting the lateral bending generated in the hot rolling process of a u-shaped steel sheet pile, the outer face of one flange of the steel sheet pile is pressed while the inner face of the other flange is pressed. U-shaped sheet pile straightening method.

2. A first jig having a surface for pressing the outer surface of one side flange of the U-shaped sheet pile, and a second jig connected to the first jig and having a surface for pressing the inner surface of the other flange. A U-shaped sheet pile straightening jig characterized by combining both jigs.

3. The first jig, which has a surface that presses the outer surface of the flange of the U-shaped steel sheet pile, has a jig that can be attached to and detached from the first jig that presses the inner surface of the flange. 3. The jig for correcting a U-shaped steel sheet pile according to claim 2, wherein the jig is provided at a connecting portion of the steel sheet pile.

4. An adjustment mechanism that can change the relative position in the product width direction of the second jig that presses the inner surface of the flange, compared to the first jig that has a surface that presses the outer surface of the flange of the U-shaped steel sheet pile. 4. The jig for correcting a U-shaped steel sheet pile according to claim 2, wherein the jig is provided at a connecting portion of the two jigs.

5. In the method of straightening U-shaped steel sheet pile rollers consisting of a web, a flange, and a joint, and having an arm between the joint and the flange, the arm is added in the vertical direction in addition to the web, the flange. A straightening roller for a U-shaped steel sheet pile having an arm portion, comprising using a straightening roller for restraining a sheet pile from being bent.

6. The roller correcting method for a U-shaped steel sheet pile according to claim 5, wherein the straightening roller for restraining the arm portion in the vertical direction in addition to the web portion and the flange portion is constituted by an integrated upper and lower roller.

7. The roller straightening method for U-shaped steel sheet pile according to claim 5, wherein the upper and lower straightening rollers are vertically arranged in a staggered manner.

8. When the arm between the flange part and the joint part is restrained, the arm part is characterized by using a straightening roller for restraining the arm from a vertical direction at an angle different from the product cross section. 5. The method of straightening rollers for U-shaped sheet piles according to 5.

9. The method for correcting the edge of a U-shaped steel sheet pile according to claim 8, wherein the straightening roller for restraining the arm portion in the vertical direction in addition to the web portion and the flange portion. .

10. The method of straightening a U-shaped steel sheet pile according to claim 8, wherein the straightening rollers are arranged vertically in a staggered manner.