JPH11179592A - Material for backing in welding square column and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the material for a backing in welding to be passed in a trapezoidal panel when employed and used in the welding with a diaphragm, and to be provided in a flat condition and bent to meet a groove at a joint part to connect square columns different in external dimensions to each other. SOLUTION: This material for a backing is a steel plate of rectangular section, and comprises two or three straight parts 21A, 21B respectively constant in width, and one or two bent parts 22 therebetween, the bent part 22 is constant in width 23 in the longitudinal direction of the steel plate, and provided with a group of grooves 24 parallel to each other. In a manufacturing method of the material of the backing for welding, adjacent materials of a plurality of backings are brought into close contact with each other, the cutting position is arranged so that the bent parts are arranged on the same line, and the boundary with the adjacent material for the backing is successively cut by a cutting means to make the cutting along the cutting line.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backing used for welding a trapezoidal panel to a through-diaphragm arranged above and below a connecting portion connecting square columns having different external dimensions. It is about money.

[0002]

2. Description of the Related Art The size of one side of a square column or the like is gradually reduced as it goes to the upper floor of a building. At this time, columns having different external dimensions must be connected at a connection portion. . As shown in the perspective view of the connecting portion in FIG. 2, in a connecting portion in which a diaphragm is provided up and down and a panel is provided therebetween, in such a case, a corner whose side length gradually decreases from the lower end toward the upper end. The most basic method is to use a tapered cylindrical panel, that is, a trapezoidal panel 2. In this case, the outer dimensions of the upper end and the lower end of the trapezoid panel 2 correspond to the outer dimensions of the upper and lower square columns 5 and 6, respectively, and the end face of the square column and the end face of the trapezoid panel sandwich the upper and lower diaphragms 3 and 4. Will be. In the drawing, reference numeral 7 denotes a bracket for attaching a beam.

In addition to the above, the outer dimensions of the panel are the same as those of the lower pillar, that is, the larger pillar, and a pillar having a smaller outer dimension is connected to the upper diaphragm. There is also a way to do it. In this case, it is necessary to reinforce the diagonal reinforcement by welding the diagonal reinforcement so as to surround the root of the upper column, or by inserting an inner diaphragm into the upper column. On the other hand, the method using the trapezoidal panel shown in FIG. 2 has a simple structure and is an excellent method without any difficulty in the flow of stress, but has a problem that welding is difficult.

That is, when a trapezoidal panel is used, FIG.
As shown in the cross-sectional view of the panel portion 1, the welding of the trapezoidal panel 2 and the upper and lower diaphragms 3 and 4 is a butt welding of an inclined T-shape. Since welding is possible only from the outer surface, the backing metal 8 is used, and multi-layer welding is performed by arc welding such as carbon dioxide gas arc welding or covered arc welding.
It was extremely difficult to bring the backing metal 8 into close contact with the material to be welded, and welding defects were likely to occur. A general backing metal is manufactured by bending a flat bar to have a length obtained by dividing the entire circumference of a square column into, for example, two or four parts, and temporarily welding it to a groove portion. If the flat bar is bent normally, the shape is the same in the width direction. On the other hand, the trapezoidal panel 2 is inclined, so that this and the backing metal 8 come into line contact as shown in FIG. For this reason, if the gap is large, the wire contact portion is melted down during welding work, and welding defects are likely to occur. In particular, a gap is easily formed in a corner portion, and welding defects often occur.

As a backing metal for a welded portion having an arc portion and a straight portion such as the inner surface of a square column, a method of using a corner block of a predetermined shape for the arc portion and using a flat plate for the straight portion therebetween. It is known that such a method is applied as a means for solving the above problem. In other words, in this case, the trapezoidal panel 2 is constituted by eight divided members combining a flat plate and a corner block having an angle corresponding to the inclination of the trapezoidal panel 2. However, this method has a problem that the production of the corner block is complicated, and it takes time to temporarily assemble the backing material divided into eight.

There is a backing metal for welding a square column, which is provided as a flat steel sheet having a group of grooves provided in advance at a portion to be bent. Such a backing metal steel plate is used in the field by bending it at the groove portion with human power or a simple tool. Until then, it is flat and convenient for handling such as transportation and storage. FIG. 12 is a perspective view showing an example of a conventional backing metal material.
In the invention of JP-A-79-79, a group of V-grooves 16 having a specified number of groups of 8 or more and 10 or less is provided in a portion of the steel plate 15 to be bent. However, even in the case of such a conventional backing metal steel plate, the shape is the same in the width direction when it is bent, and when used for welding a trapezoidal panel, the above-described problem of occurrence of welding defects occurs.

[0007]

SUMMARY OF THE INVENTION The present invention is a material for a welding backing metal provided in a flat state and bent to fit a groove, and is used for joining square columns having different external dimensions. When using a trapezoidal panel at the mouth,
This is intended to solve the above-mentioned problem in welding this to the diaphragm. That is, the present invention provides a backing metal that does not cause defects such as hot water leakage and burn-through during multilayer arc welding from the outer surface side of the panel at the joint between the diaphragm and the trapezoidal panel.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and comprises welding a diaphragm to each end of a square column having a different external dimension, and welding a hollow trapezoidal panel between the diaphragms. A material for a backing metal which is provided in a flat state and is bent in accordance with an inner surface of a groove of the panel and used for welding a connection portion of a square column, wherein the material for the backing metal has a square cross section. A steel plate,
It is composed of two or three straight portions each having a constant width and one or two bent portions therebetween, and the bent portion has a constant width in the length direction of the steel plate and is provided with a group of parallel grooves. A material for a welding backing metal of a square column, characterized in that: Here, the shape of the square cross section is a square in which two opposing corners are each equal to the inclination angle at the corresponding position of the trapezoidal panel,
Further, the shape of the groove is a V shape having an angle of 24 degrees or less, and the number of V grooves forming a group is 4 or more.

In producing a plurality of welding backing metal materials of the same size having two straight portions and one bent portion from one steel plate, the plurality of welding backing metal materials adjacent to each other are manufactured. The cutting positions are arranged so that they are in close contact with each other and these bent portions are aligned on the same line, and the cutting means that cuts along the cutting line sequentially cuts the boundary with the adjacent backing metal material to form a plurality. A method for producing a material for a welding backing metal for a square column as described above, wherein the material for a backing metal is cut out.

[0010]

FIG. 3 is a cross-sectional view of a panel portion using a backing metal manufactured from the material for a welding backing metal according to the present invention. The welding backing metal 1 is an extension of the inner surface 9 of the trapezoidal panel 2. It is necessary to have a shape having the same surface and having a surface parallel to the surfaces of the diaphragms 3 and 4. By doing so, the trapezoidal panel 2 and the backing metal 1 come into contact with each other not with a line but with a surface. it can.

[0011] Even in the case of a joint formed by a combination of two types of square columns having different external dimensions, the shape of the trapezoidal panel differs depending on the position of the pillar in the building. That is, FIG.
The trapezoidal panel whose four surfaces are similarly inclined as shown in the side view of FIG. 4D and the plan view of FIG. Side view,
A trapezoidal panel in which three surfaces are inclined as shown in the plan view of (e) is used, and the pillars at the corners of the building have two sides as shown in the side view of FIG. 4 (c) and the plan view of (f). A trapezoidal panel with an inclined surface is used. Therefore, it is necessary to use a welding backing metal for performing welding of one connection portion, in which the inclination angle of each side is different depending on the shape of the trapezoidal panel.
In each of the trapezoidal panels, the curvature of the corner portion 10 is generally constant without any change in the vertical direction on the inner and outer surfaces.
It is therefore not a trapezoid in the exact sense as far as this is concerned.

Since the inner surface of the panel is approximately trapezoidal as described above, the surface on the groove side of the backing metal naturally has the same trapezoidal side surface. Therefore, the backing metal for the entire circumference of the trapezoidal panel has a trapezoidal annular outer surface as shown in the perspective view of FIG. However, both the upper and lower surfaces need not be horizontal surfaces, and it is sufficient that at least only the side that the diaphragm hits is a horizontal surface. FIG. 5B is a perspective view showing a state in which the welding backing metal 1 is attached to the trapezoidal panel 2, and a groove 11 is formed at each of the upper and lower ends of the panel member.
A welding backing is installed. Therefore, the material for the welding backing metal of the present invention is a material for manufacturing a material obtained by dividing the annular backing metal shown in FIG. For example, a case where two backing plates each formed by bending two portions of one steel plate into a U-shape is used.
As shown in the perspective view of one backing metal of (c), there are a case where four pieces each obtained by bending one place are used, and a case where the side part is further divided and eight pieces are used.

The material for manufacturing the backing metal as described above by bending is as long as the corner of the trapezoidal panel is vertical as shown in FIGS. 4 (c) and 4 (f). The grooved steel plate shown as the prior art can be used as it is. However, FIGS. 4 (a), (b), (d),
In the case where the corner portion is inclined as in (e) and the like, even if the above-mentioned grooved steel plate is bent, the inclined shape is not obtained. When manufacturing a backing metal used for an inclined corner by bending a flat steel plate, the length of each side in the width direction, that is, the length of the upper and lower sides must be changed. Therefore, in order to manufacture a backing metal by bending a straight steel plate having a narrow width, for example, a flat bar, it is necessary to perform processing such that the length of the lower side is longer than that of the upper side. However, it is impossible to extend one side by itself by pulling it by human power. There is no other way than to change the curvature of the corner in the width direction by devising the shape of the groove. For this reason, in the present invention, the material for the backing metal is not a straight steel plate such as a flat bar but is bent in a plane, and provides an ideal material as a welding backing metal for trapezoidal panels. What you want to do.

FIG. 1 is a view showing an example of a material for a welding backing metal according to the present invention. FIG. 1 (a) is a plan view, FIG. 1 (b) is a side view, and FIG. The material for the welding backing metal is a steel plate having a square cross section, and two straight portions 21A having a constant width.
21B and one bent portion 22 therebetween. This bent portion has a constant width 23 in the steel plate length direction,
A group of grooves 24 is provided. This material for backing metal is used by bending the trapezoidal panel and the diaphragm at the bent portion 22 at a right angle with the groove 24 inward when welding the trapezoidal panel and the diaphragm at the joint connecting the square columns having different outer dimensions of the sides. . Since the trapezoidal panel is inclined at the same angle on all four sides when bent at the bent portion 22, for example, if the trapezoidal panel is inclined at the same angle, use the same four pieces, and if necessary, lengthen the side portions. A straight backing material is added to form an annular backing. FIG. 1 is an example of a backing material used when both sides of a trapezoidal panel are inclined at the same angle. The case where one is inclined and one is vertical will be described later in detail, but the widths of the left and right straight portions 21A and 21B are different, and the cross-sectional shapes are also different between the left and right straight portions. In addition, it can be formed into a shape having three straight portions and two bent portions. In this case, since the shape becomes a U-shape when bent, for example, if two of them are used, the shape can be made annular.

The backing metal material of the present invention is bent in a flat state as described above, and has a predetermined relationship as described later with respect to the inclination angle of the trapezoidal panel to which the bending angle of the bent portion is applied. Thus, if a simple bending process is performed, the inclination of each side can be made the same as the inclination of the side surface of the trapezoidal panel. Therefore, a group of parallel steel plate width direction grooves may be provided in a portion having a constant width corresponding to the length of the arc on the inner surface of the corner portion of the trapezoidal panel. The shape of the groove is preferable because no space is created when the V-shape is bent. In this case, it is preferable that the angle of the V-groove be approximately 24 degrees or less regardless of the depth of the groove. If it is larger than this, a large dent may be formed at a position corresponding to the groove on the outer surface of the corner portion, and a gap is generated between the backing metal and the base material. Therefore, when the angle of the V-groove is exactly 24 degrees, for example, if the number of grooves in a group is at least four, the sum of the angles of the grooves becomes 90 degrees or more,
The material could be bent 90 degrees. When the angle of the V-groove is smaller than 24 degrees, the number of grooves in the group may be increased from four. The larger the number of grooves, the smoother the shape when bent, but the greater the number of grooves, Since there is no benefit in spite of the increase in processing time, 10 or less are appropriate. The material is 9
As described above, the product of the angle and the number of the V-grooves is required to be 90 ° or more in order to bend at 0 °. However, if this angle is too large, the gap at the portion where the groove was formed when bending is increased.
0 degrees or less is preferable.

As described above, the shape of the groove provided in the material for the welding backing metal of the present invention is preferably a V-shape. However, the groove is not a V-shape as shown in FIG. 6), a V-shaped groove 25 with an R at the tip or a V-shaped groove having a flat tip with a chamfered shape as shown in FIG.
The groove 26 can be similarly applied as the V groove in the present invention. In the case of such a V-groove, a slight cavity is formed at the bottom of the groove when bent, but there is no problem in practical use, and on the other hand, there is an effect that the processing cost for cutting the V-groove can be reduced. That is, when the tip of the V-groove is sharp, the cutting edge of this part such as a milling cutter is worn out sharply. be able to.

As described above, since the backing metal according to the present invention forms a corner portion by simple bending, the curvature becomes constant in the width direction of the backing metal. As described earlier with reference to FIG. 4, the trapezoidal panel itself is not a trapezoid in the exact sense,
Since the curvature of the corner portion 10 is generally constant without any change in the vertical direction on the inner and outer surfaces, this allows the backing metal to be accurately provided on the extension of the inner surface of the trapezoidal panel.
In other words, the only way to make a trapezoidal backing metal by bending a straight material such as a flat bar by hand is to change the curvature of the corner in the width direction as described above, and as a result, the inner surface of the trapezoid panel Will approximately match, but
In the present invention, they can be matched in an ideal state.

The bending angle of the bent portion in the backing metal material of the present invention is set to have a predetermined relationship with the inclination angle of the surface of the trapezoidal panel to be welded, as described above. become that way. The inclination angle of both sides sandwiching the corner portion is the same as in the case of the trapezoidal panel shown in FIGS.
As in the case of the trapezoidal panels of (b), (c), (e) and (f), one is inclined at an angle and the other is 90
In the case of the degree, that is, the vertical direction, and the lower 2 in FIG.
There are cases where both sides are inclined like two corners and the inclination angles are different. Of these three cases, the case where the second one surface is vertical is the simplest, and will be described first. FIG. 7 (a) is a perspective view of this case in a state of being bent to a right angle, and is schematically shown for convenience, that is, the corner portion is bent only by the bending line 31 instead of the arc shape, and the material is not bent. The thickness is neglected. Where 32 is a plane inclined at an angle α,
33 is a vertical plane. As is clear from this figure, the angles between the bending line 31 and the lower sides 34 and 35 of the surfaces 32 and 33 are 90 degrees and α, respectively. FIG. 7B is a plan view before bending, that is, when a flat backing material is used. From the above, the bending angle of the bent portion is 90 ° −α as shown in the drawing.
It should be understood that

FIG. 8 (a) shows a case where the inclination angles of both sides sandwiching the corner are both α, and FIG. 7 (a)
FIG. 4 is a perspective view schematically showing the bending line 4 as in the case of FIG.
It is bent at 1. Obviously, the angle between the bending line 41 and the lower sides 44, 45 of the surfaces 42, 43 is equal, but not the same as the inclination angle α of the surfaces. Therefore, this is set to θ as shown in the figure. When an auxiliary line is drawn as shown by a broken line in this figure and the lengths a and b of the line segment are determined, a and b are deleted because there is a relationship of tan θ = b / a and cos α = a / b. Then, a relationship of tan θ = 1 / cos α is derived. FIG. 8B is a plan view before bending, that is, when a flat backing metal material is used. The bending angle of the bent portion is 180 ° using the value of θ as shown in FIG. It can be seen that it should be set to -2θ. In many cases, α is up to about 70 °, that is, the inclination of the trapezoidal panel surface from the vertical is up to about 20 °, for example, α =
Since θ = 71.1 ° at 70 °, the difference between α and θ is small. Therefore, there is not much error even if the value of α is directly used as θ. However, for example, when α = 60 °, θ = 6
At 3.4 °, the difference increases as α decreases.

Further, when the surfaces on both sides sandwiching the corner are inclined and the inclination angles are different, the calculation procedure is not described again because it can be easily understood as an extension of the calculation method described with reference to FIG. If only the results are described, the inclination angles of one and the other surfaces are set to α ₁ and α ₂ respectively, and the bending line (reference numeral 41 in FIG. 8) and the lower side of the one and the other surfaces (FIG. 8)
If the angles with reference numerals 44 and 45) are θ ₁ and θ ₂ , respectively, the following two equations hold. Therefore, the bending angle of the bent portion is calculated as 180 ° −θ ₁ using the results of these equations.
The -θ _2. tan θ ₁ = (1 / cos α ₁ ) · (tan α ₂ / tan α ₁ ) tan θ ₂ = (1 / cos α ₂ ) · (tan α ₁ / tan α ₂ )

Further, in the backing metal according to the present invention, at least the side of the both sides which contacts the diaphragm needs to be parallel to the diaphragm. It is conceivable that the material for the backing metal has a rectangular cross section on the premise that the material for the backing metal is ground by a grinder or the like after bending before use. However, it is preferable that the material for the backing metal is formed in a predetermined shape in advance. For this purpose, if the cross section of the material is a parallelogram so that both the upper and lower surfaces are horizontal when bent as shown in FIG. 1, it can be used for either upper or lower welding of the trapezoidal panel. Can also be used. In this case, a pair of corners of the parallelogram may be made equal to the inclination angle of the corresponding position of the trapezoidal panel. For example, in the case of FIG. 7 (a) or FIG.
What should I do? When one side is 90 degrees, that is, perpendicular to the corner, as shown in FIG. 7A, the cross section of the 90 degrees side is a rectangle. That is, in any case, the cross-sectional shape may be a quadrangle in which two opposing corners are respectively equal to the inclination angles of the corresponding portions of the trapezoidal panel.

Note that the angle of inclination of a portion that becomes a circular arc when the corner portion is bent generally has a value different from that of the side portion. However, when one surface sandwiching the corner portion as shown in FIG. 7A is vertical, it is apparent at a glance that the inclination angle is equal to the inclination angle of the inclined surface.
Therefore, the case where the inclination angles of both surfaces sandwiching the corner portion are both α will be described with reference to FIG. 8A used in the calculation of the angle of the bent portion earlier. As shown in this figure, when the inclination angle of the bending line 41 to be determined is β and the lengths of the line segments c and d are determined, sin β = c / d. On the other hand, since there is a relationship of cos θ = a / d and tan α = c / a, if these expressions are arranged, sin β = tan α · cos
The relational expression of θ is derived. For example, when α = 70 °, since θ = 71.1 ° as described above, β = 62.
8 °. When both sides sandwiching the corner are inclined and the inclination angles are different, the calculation can be performed in the same procedure as in the case where the inclination angles are equal. If only the results are described, the inclination angles of one and the other surfaces are α ₁ and α ₂ , respectively, as described earlier when calculating the bending angle of the bent portion.
If the angles between the bending line (reference numeral 41 in FIG. 8) and the lower sides (reference numerals 44 and 45 in FIG. 8) of the one and other surfaces are θ ₁ and θ ₂ , respectively, sin β = tan α ₁・ Cos θ ₂ ＝
the tan α ₂ · cos θ _1.

Therefore, when both surfaces sandwiching the corner are inclined, the angle of the parallelogram of the cross section at the center of the bent portion to be the center of the arc of the corner is β, and It is only necessary to sequentially shift to an angle α (α ₁ and α ₂ when the inclination angle is different) over the portion. When one side is inclined at an angle α and the other is 90 degrees, that is, vertical, the opposing corners of the quadrangular section may be sequentially shifted from α to 90 ° at the corners. If both sides sandwiching the corner are also inclined at the same inclination angle, the corner is also assumed to have the same cross-sectional angle α as the side, and after bending, make some rework with a grinder etc. Is also good.

The present invention also provides a method for efficiently producing the above-mentioned backing material without wasting any material. That is, since the material for the backing metal of the present invention is bent in a plane, a flat bar or the like cannot be made into a material unless it is assumed that plastic working is performed. Therefore, the material for the backing metal of the present invention is manufactured efficiently at low cost by using a steel plate as a raw material and performing a processing step of merely cutting. That is, in the method of the present invention, a plurality of backing material materials are cut out in a steel sheet by cutting the boundaries between adjacent backing material materials in parallel sequentially by cutting means for cutting along the cutting line. .

FIG. 9 shows the cutting position of the backing material when one of the inclination angles of both sides sandwiching the corner is inclined at a certain angle and the other is vertical as shown in FIG. It is shown. FIG. 9 (a) is a plan view, in which 51 is a material steel plate, 20 is a material for each backing metal, and FIG. Above. Reference numeral 24 denotes a group of grooves, which are provided on the back side in the figure. That is, in order to make it easier to understand the correspondence with FIG. 7, the paper is bent so that the paper side becomes convex when the backing metal is used. However, the groove 24 is shown in FIG.
As shown in (a), it may be cut before cutting, or may be cut individually in the form of a backing material.
In any case, a horizontal milling machine or the like can be used as a grooving device.

As shown in FIG. 9A, the cutting positions may be arranged such that the positions of the bent portions of the plurality of backing metal materials, ie, the positions of the V-grooves, are on the same line in the width direction of the backing metal. is necessary. With such a positional relationship, the width of the necessary backing metal can be ensured without any excess or shortage by plate-cutting the adjacent backing metal materials so as to be in close contact with each other, and waste of the material can be minimized. That is, in FIG. 9 (a), the width measured at right angles to the length direction of the backing metal material is 1 / cos α longer on the right side of the bent portion than on the left side. Since it is inclined by α, all the height dimensions when the backing metal is used eventually become uniform.

FIGS. 9B and 9C show AA respectively.
FIGS. 9A and 9B are cross-sectional views taken along line BB. The width end of the surface that is inclined when used as a backing metal is cut obliquely as shown in FIG. 9C, and a pair of parallelograms in the cross section is cut. Is just required to be equal to the above-mentioned inclination angle α of the surface, as described above. As described above, the cutting angle may be sequentially shifted from α toward the other surface at the bent portion to 90 ° shown in FIG. 9B. Since the inclination angle at the time of cutting can be the same on both sides of the width, that is, on the upper and lower sides at the same position in the length direction when it is made as a backing metal,
By simply cutting the boundary between adjacent backing metal materials at a predetermined angle of inclination, the condition of the angle of inclination can be satisfied for both adjacent materials.

FIG. 10 shows a method of cutting a material in the case of a backing metal in which both sides of the corner are inclined at the same inclination angle as shown in FIG. Is a plan view, and (b) is an AA cross-sectional view. In this case, too, the concept is the same as that of FIG. However, as described above with reference to FIG. 8A, in this case, the inclination angle α of the cutting is usually slightly different from the angle θ of the bent portion. In the bent portion, it is preferable to change the inclination angle of the cutting to β smaller than α (FIG. 8). Further, when the surfaces on both sides sandwiching the corner portion are inclined and the inclination angles are different, it is obvious that the same method as in the case where the inclination angles in FIG. 10 are equal can be manufactured. That is, a pair of angles of the parallelogram in the cross section corresponding to the inclination angles α ₁ and α ₂ of the respective surfaces are α ₁ and α, respectively.
_2, and the angle between the direction of the group of grooves and the length direction of each of the above-described surfaces is θ ₁ , θ as described above in the calculation method.
It should be ₂ . Note that the manufacturing method of the present invention shown in FIGS. 9 and 10 is applicable only when manufacturing a backing material having two straight portions and one bent portion. This is because when there are two bent portions, it is impossible to arrange a plurality of backing metal materials so that both bent portions are on the same line in the width direction.

As described above, by cutting a plurality of materials for the backing metal by sequentially cutting the boundary between the adjacent materials for the backing metal, it is possible to minimize waste of the material.
Since the boundary between two adjacent materials can be cut in one operation, the work efficiency is high. As the cutting means, one that cuts along a cutting line is used. This refers to, for example, a band saw that is sequentially cut by a feeding means or the like, but gas cutting or plasma cutting is particularly suitable because the cutting angle can be easily changed while cutting, and work efficiency is high. For example, the cutting torch can be moved in the X and Y directions and mounted on a table on which the inclination angle of the torch can also be controlled, and by performing a copying operation by numerical control, the cutting torch can be moved along a predetermined trajectory and inclination angle on a steel plate of the material. It can be moved to perform the cutting operation automatically.

[0030]

The welding backing metal material of the present invention can be formed into a shape along the inner surface of the groove portion of the trapezoidal panel when the material is bent at the bent portion with the groove inside in use, and the material to be welded is linear. Since the contact can be made without any surface, the molten metal can be prevented from being melted down and defects caused by molten metal leakage can be prevented. Further, in manufacturing the backing material of the present invention, by arranging the cutting position in the steel plate of the material so that the bent portion of the plurality of backing material is aligned on the same line, the boundary between adjacent materials. It is possible to cut out a plurality of materials for the backing metal by cutting sequentially, and work efficiently with minimum waste of the material.

[Brief description of the drawings]

FIG. 1 is a view showing an example of a material for a welding backing metal of the present invention;
(A) is a plan view, (b) is a side view, and (c) is an AA cross-sectional view.

FIG. 2 is a diagram showing a connection portion formed by trapezoidal panels;

FIG. 3 is a sectional view of a panel using a backing metal according to the present invention.

FIGS. 4A and 4B show various shapes of a trapezoidal panel.
(C) Side view and (d), (e), (f) plan views

5 (a) is a perspective view showing the entire periphery of a trapezoidal panel of a welding backing metal according to the present invention, (b) is a perspective view showing a state of being attached to the trapezoidal panel, and (c) is a perspective view showing one backing metal.

FIGS. 6 (a) and 6 (b) are views showing examples of the form of a V-groove in a material for a welding backing metal according to the present invention.

FIG. 7A is a schematic perspective view and FIG. 7B is a plan view for explaining the relationship between angles in the welding backing metal material of the present invention.

8 (a) is a schematic perspective view, and FIG. 8 (b) is a plan view, for explaining the relationship of angles in the welding backing metal material of the present invention.

9 (a) is a plan view, and FIGS. 9 (b) and 9 (c) are AA, respectively, showing a method of cutting the material for welding backing metal of the present invention.
And BB sectional view

10 (a) is a plan view, and FIG. 10 (b) is a sectional view taken along the line AA, showing a method for cutting the material for welding backing metal of the present invention.

FIG. 11 is a cross-sectional view of a panel portion showing a usage state of a conventional welding backing metal.

FIG. 12 is a perspective view showing an example of a conventional backing material.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 backing metal 2 trapezoidal panel 3, 4 diaphragm 5, hexagonal column 7 bracket part 8 backing metal (background) 9 inner surface of trapezoidal panel 10 corner part 11 groove 15 steel plate 16 groove 20 material for backing metal 21 A, 21B Straight portion 22 Bending portion 23 Width 24 groove 25, 26 V groove 31 Bending line 32, 33 surface 34, 35 Lower side 41 Bending line 42, 43 surface 44, 45 Lower side 51 Steel plate of material

Claims (4)

[Claims] 1. A flat state for welding a joint of a square column formed by welding a diaphragm to each end of a square column having different external dimensions and welding a hollow trapezoidal panel between the diaphragms. Wherein the backing material is a steel plate having a square cross section and has a constant width of two or three straight portions, each of which has a constant width. 1 or 2 in between
Characterized in that the bent portion has a constant width in the length direction of the steel plate and is provided with a group of parallel grooves. 2. The welding back of a square column according to claim 1, wherein the square cross section has a shape in which two opposing corners are each equal to the inclination angle at a corresponding position of the trapezoidal panel. Materials for backing. 3. The corner according to claim 1, wherein the shape of the groove is a V shape having an angle of 24 degrees or less, and the number of V grooves forming a group is 4 or more. Material for column welding backing metal. 4. A method of manufacturing a plurality of same-sized welded backing materials having two straight portions and one bent portion from a single steel sheet, wherein the plurality of welded backing materials are adjacent to each other. The cutting positions are arranged such that the objects are in close contact with each other and these bent portions are aligned on the same line, and the cutting means that cuts along the cutting line sequentially cuts the boundary with the adjacent backing metal material. The method for producing a welding backing material for a square column according to any one of claims 1 to 3, wherein a plurality of backing material materials are cut out.