JP2000158191A - Backing metal fittings for H-beam welding - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide an H-shaped steel backing metal fitting which is low in processing cost and does not require a separate piece. SOLUTION: A U-shaped hole 1b is punched out while leaving a root gap at a longitudinal center portion of a strip-shaped backing metal plate 1, and both sides of the U-shaped hole 1b are bent downward in an arc shape. In the backing metal fitting for forming an H-shaped steel in which the rounded portion 1a is formed, the wall surface on the root gap side of the narrow bridge portion at the center of the backing metal fitting 1 is formed as an inclined surface 1c inclined inward downward.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backing metal fitting for securing a root gap for welding without requiring scalloping at the time of welding an H-section steel in a steel frame work in construction.

[0002]

2. Description of the Related Art In steel structures such as buildings, beams,
When butt welding H-beams as girder materials,
A backing metal fitting for welding is used to weld a flange portion of a mold steel from the front side.

[0003] For example, in Japanese Patent Publication No. 51-29505, a back penetration metal fitting having a curled portion and a straight portion is attached to a full penetration welded joint of an H-shaped steel flange portion having a root gap, and the curled portion is formed at the base of the flange and the web. There is disclosed a welding method in which a straight portion is attached and welded along a circular arc so that a straight portion fits between a root gap of a root of a web and a flange. In addition, 5
Japanese Patent Application Laid-Open No. 9-42237 discloses a backing material for H-type steel welding in which a part of a flat steel is cut out and the corner of a groove is processed into an arc shape. Further, Japanese Utility Model Publication No. 6-38619 discloses a mounting structure of a steel bar in which an end of a flat steel is bent to conform to a cross-sectional shape of an H-shaped steel.

However, the above-mentioned Japanese Utility Model Publication No. 59-4223.
In the backing material disclosed in Japanese Patent Publication No. 7, there is a problem that the arc-shaped processing is troublesome even if it is cut, and the cost is high. Furthermore, the above-mentioned actual fairness 6-38619
In the structure disclosed in Japanese Patent Application Laid-Open Publication No. H10-209, bending can be made, but there is a problem that handling is inconvenient because it is divided into two members. Therefore, the above-mentioned Japanese Patent Publication No. 51-29
The backing described in US Pat. No. 505 is considered to be suitable.

[0005] However, Japanese Patent Publication No. 51-29505 describes that these backing plates can be mass-produced by pressing, but the shape is actually a part of a thick flat steel plate. It is extremely difficult to cut and bend while cutting in the longitudinal direction, and the fact is that it has not been realized yet. Referring to FIG. 5, the following four points are required for the precision required for the metal fitting disclosed in Japanese Patent Publication No. 51-29505. (1) Ensuring the root gap (t) for welding (2) Squareness and flatness of the H-shaped steel end surface contact portion 11c (3) Close contact of the curled portion 11a of the backing metal fitting 11 with the R portion 12a of the H-shaped steel 12 Degree (4) Clearance dimension 11 with respect to thickness 12b of H-section steel 12
d

[0006] In order to satisfy these precisions, the present applicant has first disclosed in Japanese Patent Application Laid-Open No. 10-156438.
A first step of punching out a U-shaped hole while leaving a root gap at a longitudinally central portion of a strip-shaped backing metal plate, and both sides of the U-shaped hole of the backing metal plate manufactured in the first step And a second step of bending the portion downward into an arc shape.

FIG. 4 (a) shows a punching step, in which the first upper die 13 leaves a U-shaped hole with a root gap t at the center in the longitudinal direction of the strip-shaped backing metal plate 11. Punch 11e. The first lower mold 14 is provided with a hole 14a into which the upper mold 13 fits. Next, FIG.
As shown in the figure, the portions on both sides of the U-shaped hole 11e are formed into an arc. The lower part of the second upper die 15 for molding has a straight portion 15a having a width of the U-shaped hole 11e and an arc portion 15a on the lower portion.
b. The second lower mold 16 has a rectangular hole 16a for receiving the linear portion 15a of the second upper mold 15, and a concave portion 16b corresponding to the curled portion 11a of the backing fitting product.

By these two steps, the dimensions of the root gap (t) for welding are ensured, the perpendicularity and flatness of the H-shaped steel end surface contact portion 11c, and the curled portion 11a of the backing metal fitting 11 to the R portion 12a of the H-shaped steel 12. The degree of adhesion and the clearance 11d with respect to the thickness 12b of the H-shaped steel 12 can be accurately determined.

[0009]

However, according to the method disclosed in Japanese Patent Application Laid-Open No. H10-156438,
R part 12a of wedge part of H-section steel 12 by press working
However, as shown in FIG. 6A, simply chamfering the shoulder 12c of the H-shaped steel 12 by a non-scallop method or the like as shown in FIG.
2c cannot be used because it hits the inner wall 11e of the backing metal plate 11. In addition, special groove processing is required.

[0010] As shown in the backing metal fitting 21 shown in FIG.
Although there is a conventional product in which the portion 21a that contacts the shoulder of the H-shaped steel is formed obliquely, the cost is high because it is a three-dimensional and complicated cut product. Further, a split backing metal fitting 3 as shown in FIG.
In the case of 1 and 32, since a gap 33 is formed between the two backing fittings 31 and 32, a welding defect is likely to occur, so another triangular piece is required. The problem to be solved by the present invention is
An object of the present invention is to provide a backing metal fitting of H-shaped steel which has a low processing cost and does not require a separate piece.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a backing metal fitting for welding an H-shaped steel according to the present invention is punched while leaving a root gap at a longitudinally central portion of a strip-shaped backing metal material plate. In the backing fitting in which both sides of the removed U-shaped hole are bent downward in an arc shape, the wall surface on the root gap side of the narrow bridge portion in the center of the backing fitting is inclined inward downward. It is a thing.

[0012]

Embodiments of the present invention will be described below. 1A and 1B show a backing metal fitting for H-beam welding according to the present invention, wherein FIG. 1A is a plan view, FIG. 1B is a front view, and FIG.
FIG. 4 is a sectional view taken along line AA of FIG. In the figure, reference numeral 1 denotes a backing metal, which is a U-shaped hole 1 punched out at the center in the longitudinal direction of a strip-shaped backing metal plate, leaving a root gap.
b on both sides are bent downward in an arc shape,
a. In addition, the wall surface on the route gap side of the narrow bridge portion in the center of the backing fitting 1 is formed as an inclined surface 1c inclined inward downward.

FIG. 2 shows a method of machining the inclined surface 1c.
As shown in (a) is a front view of a main part, and (b) is a cross-sectional view, the excess portion 1d of the punched backing fitting 1 is obliquely cut by the end mill 2 or FIG. (A) is a front view of a main part, and (b) is a sectional view.
Can be cut obliquely using a special tool 3 having a trapezoidal blade.

[0014]

As described above, according to the present invention, it is possible to provide a backing metal fitting that does not hit the chamfered portion of the H-shaped steel by performing the pressing and the simple cutting, and does not require another piece. This has the effect of being

[Brief description of the drawings]

1 shows an embodiment of the present invention, in which (a) is a plan view, (b) is a front view, and (c) is a cross-sectional view taken along the line AA of (b).

2A and 2B show a method for processing an inclined surface according to the present invention, wherein FIG. 2A is a front view of a main part, and FIG.

3A and 3B show another method of processing the inclined surface of the present invention, wherein FIG. 3A is a front view of a main part, and FIG. 3B is a sectional view.

FIG. 4 is a schematic view showing the steps of a press working method of the backing fitting.

FIG. 5 is a perspective view illustrating the accuracy required for the backing fitting.

FIG. 6 is an explanatory view for explaining a problem of a conventional backing fitting.

FIG. 7 is a perspective view showing an example of a conventional backing member.

FIG. 8 is a perspective view showing an example of a conventional backing member.

[Explanation of symbols]

1 Backing metal fittings, 1a radius part, 1b U-shaped hole, 1c
Inclined surface, 1d extra thickness, 2 end mills, 3 special tools

Claims (1)

[Claims] 1. A backing fitting in which both sides of a U-shaped hole punched out leaving a root gap at a longitudinally central portion of a strip-shaped backing fitting material plate are bent downward in an arc shape. A back metal fitting for H-beam welding, wherein a wall surface on the root gap side of the narrow bridge portion at the center of the back metal fitting is inclined inward downward.