JPH049639B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a method of manufacturing a square steel pipe column having a built-in stiffener.

``Prior art'' Rectangular closed cross-section members such as square steel pipe columns have higher torsional rigidity than open cross-section members, and due to their mechanical properties of having no directionality in bending rigidity, they are often used as main column materials. However, in this case, stiffeners are attached inside to reinforce structurally important locations such as joints with beams.

In other words, when manufacturing a square steel column that is assembled from four cut plates, four of the stiffeners inserted into the square column are
A method for attaching and welding the sides is known, for example, in Japanese Patent Publication No. 51-15497. This method, as shown in FIG. 18, combines prismatic skin plates 31, 31' and stiffeners 32,
33' are joined by conventional welding (SMAW, GMAW, etc.), and then assembled into a prism with skin plates 34, 34', and the remaining two symmetrical sides 35, 3 of the stiffener 32 are
Weld 5' with ESW. After that, the process of seam welding the corners of the prism is followed.

However, this method requires a narrow work space for attaching and welding the first two sides of the stiffener 32, resulting in low welding reliability and low work efficiency.

Moreover, in order to ensure the welding position (sideways),
It is necessary to rotate the semi-assembled prism several times, which further reduces work efficiency and is also unfavorable from a safety standpoint. In addition, skin plates 31, 3
In order to perform ESW for attaching the stiffener 32, a cutout groove 36 must be provided in advance in 1'. Requires complicated work. Furthermore, as shown in FIG. 19, unwelded portions M remain at the corners of the stiffener 32, resulting in structural mechanical problems.

In the installation welding of the first two symmetrical sides of the stiffener 32, the Japanese Patent Publication No. 50-35487 is used as an alternative to GMAW or SMAW, which has poor welding reliability and efficiency.
number is known. In this method, as shown in FIG.
Temporarily assemble the stiffener 38 into a prism using the four skin plates 31, 31', 34, and 34'.
3' is welded by ESW, and the remaining two symmetrical sides 35, 35' are also welded by ESW, and then the four corners 39 of the prism are seam welded.

However, in this method, as shown in Fig. 21, the skin plates 31, 31' are provided with grooves 36 for later ESW.
, and also on the skin plates 34, 34'
It is necessary to prepare the hole 40 for ESW in advance, it is necessary to close the groove 36 in the first ESW, and because end tabs are used at the start and end of welding, there is no need to remove the skin after welding. The preparation work of the plate surface, as shown in Fig. 22, after
Welding itself is more efficient than conventional welding (SMAW, GMAW), but the overall amount of work increases, as drilling is required to penetrate the ESW groove. Also, since all four sides of the stiffener are ESW welded, a large amount of thick flat steel auxiliary material is consumed for the backing metal. There were drawbacks such as:

Japanese Patent Publication No. 59-21714 has been proposed as a method that can omit such troublesome work.

This method, shown in FIG. 23, involves welding two symmetrical sides 33, 33' of the stiffener 32 to the start metal position using a start metal fitting 41 and a metal fitting 42 for preventing burn-through of the start metal when temporarily assembling a square column in a U-shape. From stiffener 3
2 up to the upper end 43, then attach the skin plate 34 to assemble the prism, weld the remaining two sides 35 and 35' of the orthogonal stiffeners using ESW, and finally weld the four corners of the prism. The feature is that the parts are seam welded.

"Problems to be Solved by the Invention" However, the method of this Japanese Patent Publication No. 59-21714 also applies to the skin plates 31 and 31'.
As in the case of Japanese Patent Publication No. 50-35487, it is necessary to provide a groove for ESW, and there are also problems such as the metal fittings for preventing burn-through being unable to be removed due to welding shrinkage.

Furthermore, since the welding is started using the starting hardware, as shown in Fig. 24, the poorly fused portion 46 at the rise of the ESW cannot be completely remelted in the later ESW that intersects at right angles and remains, resulting in what is called an unwelded portion of the stiffener. There is also some fear. Furthermore, it has drawbacks such as the same large consumption of thick flat steel used for the backing metal as in Tokuko No. 50-35487.

In addition, in all three methods, the corners of the prism are seam welded after ESW welding the rear two sides of the stiffener. 45 occurred,
It is necessary to delete this and shape it by gouging or the like to match the groove shape of the seam. These operations are extremely difficult and labor-intensive, and if the groove is not properly shaped, seam welding defects may occur at this location.

"Means for Solving Problems" and "Operation" The present invention was made in view of the above circumstances, and its gist is that a web skin plate and a flange skin plate are assembled into a three-sided assembly. Assemble a square column in the shape of a square, and use a water-cooled copper pad to form grooves on the two symmetrical sides of the built-in stiffener, and perform ESW.
When welding, welding shall start from the bottom of the groove, which is the inner surface of the skin plate, and end at the perpendicular upper side of the stiffener. In the manufacturing of a square steel pipe column with built-in stiffeners, we will perform seam welding at the four corners, then drill holes with a drill, etc., and weld the remaining two unwelded sides of the stiffener with ESW. This method eliminates all the drawbacks of conventional manufacturing methods, allows the four sides of the stiffener to be completely securely attached without any unwelded parts, and makes it possible to efficiently manufacture a square column.

"Example" This will be explained in detail below based on the drawings.

First, as shown in FIG. 1, using prismatic web skin plates 1, 1' and flange skin plates 2, a prismatic column is assembled in a U-shape while attaching stiffeners 3 at predetermined positions. In this case, the skin plates 1, 1' have grooves 4 for seam welding at the corners of the prisms, and backing metals 5, 5' for seam welding are attached, but the stiffeners 3 are not attached at the mounting position. As shown in Fig. 2, a notch 6 is provided for the required length (stiffener plate thickness + ESW backing plate thickness x 2), and the stiffener 3 is provided with a notch 6 of the required length (stiffener plate thickness + ESW backing plate thickness x 2). As shown, skin plate 2 and ESW backing metal 7
In order to prevent the inflow of molten slag and molten metal during ESW welding of the two symmetrical sides 9 and 9', which is the first step of attaching the stiffener, an inflow prevention metal fitting 10 is installed in the groove groove 8 consisting of Install it in advance. In addition,
For the backing metal 5' attached to the web skin plates 1 and 1', remove the part 11 to a length equivalent to the plate thickness of the stiffener by gas cutting or the like, as shown in Fig. 5, at the mounting position of the stiffener. Good too. In this case, the ESW backing metal 7 can be provided with grooves 12 at both ends through which the seam backing metal 5' can pass through, as shown in Figure 6, even if there is an error in the mounting position of the stiffener. Easy to assemble. Further, the ESW backing metals 7, 7' may be attached while setting the stiffening material when assembling the U-shaped rectangular column.

After assembling the U-shaped prism with built-in stiffeners in this way, as shown in FIG.
9' are joined by ESW, and during welding, groove grooves 14, 14' are formed with a water-cooled copper pad 13, a welding nozzle 16 that guides the welding wire 15 is inserted into the groove, and the skin for the flange is joined. From the inner surface of plate 2, that is, the bottoms 17 and 17' of the bevel grooves
Start ESW. FIG. 8 is a view taken along line B-B' in FIG. 7, but as shown in FIGS.
Alternatively, the groove groove 14 may be formed.

As shown in FIG. 11, ESW finishes the first process of welding when the filled weld metal 19 rises to the upper end 20 of the stiffener 3.

After that, as shown in FIG. 12, the seam metal fittings 21 are attached between the ESW backing metals 7' which are perpendicular to each other so that the seam welding backing metal 5 is continuous, and the flange skin plate is attached as shown in FIG. 13. Assemble the closed cross-section prism at 2'. In this way,
The four seam welding grooves 4 at the corners of the prism shown in FIG. 13 are welded in a downward welding position.

After this seam welding is completed, the remaining two sides of the unjoined portion of the stiffener 3 are prepared for welding. That is, as shown in FIG. 14, the remaining two symmetrical sides 2 of the unjoined part of the stiffener 3
2, 22', ESW backing metal 7,
A hole is made with a drill or the like from the surface side of the bead 23 of the corner seam so as to pass through the bevel grooves 8, 8' formed by the grooves 7'. In this way, as shown in FIG. 15, the welding nozzles 16 are inserted into the ESW grooves 8 and 8', and the water-cooled copper pad 2 for starting welding is attached to the outer surface of the web skin plate 1'.
Start welding with ESW from 4, welding wire 15
By supplying the weld metal 19, the grooves 8, 8' are filled with the weld metal 19 as shown in FIG. 16, and when the weld metal 19 crosses the upper surface 25 of the skin plate 1, ESW welding is completed. in this case,
A copper water-cooled end tab 26 may be used on the upper surface of the skin plate to protect the molten slag and weld metal.

FIG. 17 shows that by this welding, the four sides 9, 9', 22, 22' of the stiffener 3 are connected to the skin plates 1, 1'.
2 and 2' are completely welded together without leaving any unwelded corners.

"Effects of the Invention" If a square steel pipe column with a built-in stiffener is manufactured by the method of the present invention described above, the following effects can be obtained.

(1) It is possible to manufacture a square steel pipe column in which the four sides of the stiffener are completely welded without leaving any unwelded parts.

(2) It is efficient because the first two symmetrical sides of the stiffener are also ESW-welded, and it is efficient because the next process can proceed without repairing the upper and lower ends.

(3) Furthermore, since a water-cooled copper pad that can be used repeatedly is used, auxiliary materials can be omitted.

(4) If a welding defect occurs in ESW using a water-cooled copper pad, it is easy to repair.

(5) Final welding of stiffener installation (remaining 2 steps of 2nd process)
Since the corner seam welding of the prism is performed before the side installation), the conventional method at the diaphragm position is
There is no need to remove excess bead length from ESW welding or shape the seam groove shape.

(6) There is no need to form a seam groove at the diaphragm position, and seam welding can be performed with the groove in the general part continuing as it is, so welding defects will not be concentrated at the same position.

(7) There is no need to provide a cutout groove or the like in advance at the stiffener mounting position of the skin plate, and the seam beveling process is simple and easy.

(8) The manufacturing process of the square column can be simplified and the manufacturing cost can be reduced.

[Brief explanation of drawings]

1 to 17 are explanatory diagrams of the method of the present invention, and FIG. 12b shows a view taken in the direction of arrow b in FIG. 12a. 1st
Figures 8 and 19 are explanatory diagrams of an example of conventional means;
0 to 22 are explanatory diagrams of other examples of the conventional means, and FIGS. 23 to 25 are explanatory diagrams of still other examples of the conventional means. 1, 1'... skin plate, 2... skin plate for flange, 3... stiffener, 4... groove for seam welding, 5, 5'... backing metal, 6... notch, 7,
7'...Backing metal for ESW, 8,8'...Bevel groove for ESW, 9,9'...2 symmetrical sides, 10...Inflow prevention hardware,
11...Deletion part, 12...Groove, 13...Water-cooled copper pad,
14, 14'...Bevel groove, 15...Welding wire, 16
... Welding nozzle, 17, 17'... Bottom, 18... Steel backing metal, 19... Welding metal, 20... Upper end, 21
... Seam hardware, 22, 22'... Two symmetrical sides, 23
...Bead, 24...Water-cooled copper pad, 25...Top surface, 2
6... End tab, 31, 31'... Skin plate,
32... Stiffener, 33, 33'... Two symmetrical sides, 34,
34'...Skin plate, 35,35'...Symmetry 2
Side, 36... Notch groove, 37... Backing metal, 38... Stiffener, 39... Corner part, 40... Hole, 41... Welding start hardware, 42... Welding prevention hardware, 43...
Upper end, 44... Seam welding part, 45... Extra length part.

Claims (1)

[Claims] 1. Assemble the web skin plate and flange skin plate into a U-shaped prism with three sides, form a groove on the two symmetrical sides of the built-in stiffener using a water-cooled copper pad, and perform ESW. When welding,
Welding shall start from the bottom of the groove, which is the inner surface of the skin plate, and end at the orthogonal upper side of the stiffener. After welding, a prism will be assembled on the closed cross section of the opening, and the four corners of the prism will be welded. A method for manufacturing a square steel pipe column with a built-in stiffener, characterized in that the seam welding is performed, and then a hole is made with a drill etc., and the remaining two unwelded sides of the stiffener are welded by ESW.