JPH04200871A - Composite tab material used for high heat input submerged arc welding of thick steel plate - Google Patents

Abstract

PURPOSE:To simplify handling of a tab in high heat input submerged arc welding of the extremely thick steel plate by constituting the composite tab material of a jig to hold steel material to be subjected to arc on an extension line of a groove edge of steel material to be welded via refractory members. CONSTITUTION:The steel material 1 to be subjected to arc is set on the channel bottom of the recessed refractory members 2. Consequently, a recessed channel 4 is formed of the upper surface of the steel material 1 to be subjected to arc and walls of the refractory members 2 at both sides. As a result, working of the groove channel of the steel material 1 to be subjected becomes unnecessary. In addition, since the refractory members 2 holds the steel material 1 to be subjected to arc from both sides while being held by the jig having a recessed cross section made of steel, etc., it is not necessary to form it into an integral substance having the recessed cross section. Since the jig 3 holds the refractory members 2 and the steel material 1 to be subjected to arc on the extension line of a groove 23 of a box support 10, it is fitted to an end of the box 10 support by tack welding, etc., and protected from molten metal by the refractory members 2, hence it can be used semipermanently.

Description

[Detailed Description of the Invention] <Field of Application in Industry-1-> The present invention relates to tab stripping used in large heat input latent arc welding of 1W steel plates, and provides a composite tab material that can be used highly efficiently and economically. This is a proposal.

<Conventional technology> In welding general steel sheets, the welding end and starting edges of the weld nook 1 and 3 are Jl constant parts, so the bead shape and appearance are significantly inferior to the central part, and (Defects are likely to occur due to defects in the solid shape. For this reason, a temporary paulownia plate called a tab plate is temporarily attached to the welded end of the steel plate (J-welded tab plate)
Second, the quality of the steel plate is ensured by letting the weld bead escape. Note that the tab plate used is a steel plate having the same thickness as the steel plate to be welded, with a groove provided therein to accommodate the extra thickness at the welding end.

In recent years, with the increase in the size of structures such as high-rise buildings, high heat input welding of extremely thick steel plates with a thickness exceeding 30 to 40 mm has become widespread, and latent arc welding with a higher welding heat input is used. It's becoming like that. For example, box-shaped corner pillars 1 (box pillars) used as structural materials in buildings.
is manufactured by welding together four thick steel plates into a square shape. In other words, as shown in FIG. 4, the box column 10 is made of a long square steel 20 that serves as a backing metal, and a two-piece structure whose end face is melt-cut diagonally.
6. A section of square steel 20 that is assembled using long thick steel plates 21 and 22, and 224 pieces of long thick steel vj and 224 pieces are welded together. After applying two long thick steel plates 21 and butting each other to form a groove 23 for welding, this groove 23 is subjected to latent arc welding with a large heat input using multiple electrodes to integrate them. This is what I did.

<Problem to be solved by the invention> The plate thickness is 30 to 40 mm, such as the box column mentioned above.
When performing large heat input welding on extremely thick steel plates exceeding mn+, the distance between the electrodes becomes longer as the welder's heat increases and multi-electrode welding becomes longer (as a result, the crater becomes longer and a longer tab plate is required; There was a problem in that the cost of the tab plate itself was high, and it was economically disadvantageous.

This invention was proposed in view of the above-mentioned current situation, and is intended to simplify the handling of tabs in high heat input latent arc welding of extremely thick steel plates, and to save costs related to tab plates. .

<Means for Solving the Problems> To achieve the above object, the present invention is a composite tab material used for high heat input latent arc welding of thick steel plates, which is an improvement on the conventional tab plate, and which has a concave groove formed therein. It consists of a fireproof member, a steel material to be arced disposed at the bottom of the concave groove, and a jig for holding the steel material to be arced on an extension line of the groove edge of the steel material to be welded via the fireproof member. This is a composite tab material used for high heat input latent arc welding of thick steel plates.

Function: The tab material is used to release craters, but if a concave groove corresponding to the groove is not provided, there may be problems such as the excess buildup at the end becoming too high or continuous arcing not occurring. Also, if the concave groove is too large, the excess buildup at the end will be low. However, the entire tab does not need to be made of steel, as long as it can generate an arc and retain molten metal. The present invention focuses on this point, and uses a refractory to hold the molten metal, and ensures the generation of an arc by means of an arced steel material provided at the bottom of the refractory.

Here, the steel material to be arced disposed at the bottom may be replaced by cut wire or iron powder depending on the welding conditions.

The cross-sectional area of the concave groove is preferably about 50 to 80% of the groove cross-sectional area in order to adjust the height of the excess. In addition, if this refractory is used alone, it is not only unstable in terms of strength but also difficult to hold molten slag and flux, and the shape of the refractory is also limited, so it must be set in an appropriate jig made of steel, etc. It is desirable to use it.

<Example> Hereinafter, an example of the present invention will be described based on the drawings. 1st
The figure shows a cross-sectional view of the composite tab material according to the present invention, Figure 2 is a side view taken along arrow A-A in Figure 1, and Figure 3 is a welding of a box column when the composite tab of the present invention is applied. A cross-sectional view of the joint is shown.

In FIGS. 1 and 2, reference numeral 1 denotes a steel material to be arced which is temporarily welded on an extension of the open end of the box column, and the steel material to be arced 1 is set at the bottom of a groove of a refractory member 2 having a concave shape. As a result, a concave groove 4 is formed between the upper surface of the arced steel material 1 and the walls of the refractory member 2 on both sides. This concave groove 4 corresponds to a bevel groove formed on the top surface of a normal tab plate.

By improving the ordinary tab plate to such a structure, the arced steel material can be grooved. Not only does the processing of M become unnecessary, but also a plate thinner than the thickness of the material (plate) to be welded can be used. As such a steel material, square steel or flat section steel used for the backing material can be used as is. As a result, the cost of the arc generating member can be significantly reduced.

The refractory member 2 is held in a jig 3 made of steel or the like with a concave cross section, and has a structure in which the arced steel 1fA' 1 is sandwiched from both sides, so there is no need to form it into a single piece with a concave cross section. As shown in the figure, a refractory member 2a having a cross section and a refractory member 2b having an I-shape cross section may be combined. The cost of this fireproof member 2 is much lower than that of steel. The jig 3 is attached to the end of the box column 10 in order to hold the refractory member 2 and the steel material 1 to be arced on the extension line of the groove 23 of the box column 10 as shown by the dashed line as shown in FIG. Attached by temporary welding etc. Since this jig 3 is protected from molten metal by the fireproof member 2, it can be used semi-permanently.

The composite tab material of the present invention is manufactured by manufacturing the box column 1 as described above.
It is set at the open end of 0. Once set in this manner, welding was performed under the welding conditions shown in Table 1. As a result, welding was successful, no different from when using a normal tab plate. In addition, depending on conditions such as slow welding speed, the use of arced steel materials - 1) continuous firing of the arc. If this is ensured, it is possible to use Katsuwai V or iron powder instead of the arced steel material l of the section steel.

<Effects of the Invention> As described above, according to the present invention, it is possible to downsize the arced steel material 1 and also eliminates the need for beveling. On the other hand, even though the fireproof member 2 is disposable, its cost is much lower than that of a commonly used tab plate, and the jig can be used semi-permanently. Costs can be reduced significantly.The biggest advantage is that groove processing can be omitted.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of the composite tab material according to the present invention; FIG. 2 is a side view without showing the Δ-Δ arrow direction of FIG. 1;
The figure is a front view showing an example of the weld joint groove shape of a box column when using the composite tab material of the present invention, and FIG. 4 is a front view showing a general box column. DESCRIPTION OF SYMBOLS 1...Steel material to be arced, 2...Fireproof member, 3...Jig, 4...Concave groove, 10...Box column, 20...Square steel, 21.22...Length Thick steel plate, 23...Grove for welding. Patent applicant: Kawasaki Steel Corporation

Claims (1)

[Claims] A composite tab material used for high heat input latent arc welding of thick steel plates,
a refractory member forming a concave groove; a steel material to be arced disposed at the bottom of the concave groove; A composite tab material used for high heat input latent arc welding of thick steel plates, characterized by consisting of a jig and a jig.