JPH08108882A - Fillet welded joint structure - Google Patents

Abstract

PURPOSE: To provide fillet welded joint structure ideal for the hull of a marine vessel, large in fatigue strength and low in manufacturing cost. CONSTITUTION: Fillet welded joint structure is constituted by fillet-welding a longitudinal member 11 such as facing material orthogonally to a lateral member 10 such as a web stiffener. Fillet welding 12 is applied only along the long side of the longitudinal member 11 and that it is to be end stopping beam type welding without the bead projecting outward from the long side of the longitudinal member 11. Stress concentration in conventional fillet welded joint structure with angle turning fillet welding applied is thereby reduced so as to improve fatigue strength, and manhours and manufacturing cost are reduced in comparison to the case of applying extension beam.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fillet welded joint structure, and more particularly to improvement of a fillet welded joint structure suitable for a hull structure of a ship. The present invention is applicable to marine structures and various steel structure products.

[0002]

2. Description of the Related Art As shown in FIG. 4 to FIG. 7, a slot / web stiffener 1 and a face member 2 with a longe are fillets at the joint between a horizontal member and a vertical member in a conventional hull structure such as a tanker. It is configured to be joined via a welded portion. The fillet weld also includes the corner turn fillet weld 4 applied to the end 6 of the web stiffener. That is, as shown in FIG. 7, a fillet weld joint is formed by performing corner turning fillet welding 4 on a slot / web stiffener 1 and then sequentially performing fillet welding 3 from one direction.

By the way, in such a fillet welded joint structure, since both side end portions 5 of the slot / web stiffener 1 are both linear, the slot / web stiffener 1 is formed.
At the end portion 6, the stress concentration as the discontinuous portion of the structural member becomes high. Moreover, since the corner turning fillet weld 4 is applied, high stress concentration may occur due to the toe radius of the toe portion of the weld bead and the rising angle. There is an inconvenience that the fatigue crack K to 2 easily occurs. Therefore, in order to eliminate such inconvenience, a fillet welded joint structure as shown in FIGS. 8 to 10 has been proposed.

That is, in this fillet welded joint structure, the corner turning fillet weld in the above-mentioned prior art is stopped and the weld beads of the fillet weld 3 are extended in parallel from both ends 6 of the slot web stiffener 1. The extension bead 3a is constructed (see FIGS. 8 and 9), or, as shown in FIG. 10, the extension bead 3a is extended from the end of the side fillet weld 3 in a divergent manner to fillet the weld. Measures are taken to suppress stress concentration in the joint structure. The reference numeral 1a in FIGS. 9 and 10 indicates an unwelded portion.

[0005]

By the way, the fillet welded joint structure (shown in FIGS. 8 to 10) in which the corner turning fillet welding is stopped and the extension bead is applied can improve the fatigue strength. However, there are inconveniences such as an increase in construction man-hours and an increase in weight, and it is said that there is not much merit compared to the fillet welded joint structure (shown in FIGS. 4 to 7) having corner turning fillet welding. There is a problem. The present invention is intended to solve such problems, and an object thereof is to provide a fillet welded joint structure capable of improving performance in terms of structural strength and reducing manufacturing cost. .

[0006]

In order to achieve the above object, the fillet welded joint structure according to claim 1 is a first structural member in which the fillet welded joint structure is welded at substantially right angles to each other. And a second structural member, wherein the second structural member is welded to the first structural member at the edge portion thereof by end stop bead type fillet welding.

The fillet welded joint structure according to a second aspect of the present invention is the fillet welded joint structure according to the first aspect, in order to reduce the stress concentration at the toe portion of the end stop bead type fillet weld. The welding bead of the same welding is characterized in that it is formed in a sectional shape of a concave curve that smoothly connects to the adjacent surface in the vicinity of the toe.

A fillet welded joint structure according to a third aspect of the present invention is the fillet welded joint structure according to the first or second aspect, in which the edge portion of the second structural member is formed in a substantially rectangular cross-sectional shape. , The end bead type fillet welding is carried out along the long side of the end edge portion, and at the toe portion of the welding, a slight outward protrusion of the welding beam of the welding is formed. It is characterized by being.

[0009]

In the above-described fillet welded joint structure of the present invention, since corner turning fillet welding is not applied, stress concentration generated in the welded portion of the structural member is reduced, and conventional extension beads are applied. A fillet welded joint structure having a fatigue strength performance almost equivalent to the fillet welded joint structure (joint structure shown in FIGS. 8 to 10) is obtained. Further, the fatigue strength performance is further improved by making the cross section near the toe of the weld bead into a smooth curved shape.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A fillet welded joint structure as an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view thereof, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. B-of 1
FIG.

In this embodiment, a hull structure is taken as an example, and the fillet welded joint structure is a transverse member (eg slot web stiffener) 10 as a first structural member and a second member which is welded orthogonally thereto. The vertical member as a structural member (for example, a face material with a long section) 11 is provided.
The end edge 11b of 11 is formed in a rectangular cross-sectional shape as shown in FIG. 2, and this end edge 11b is fillet welded to the lateral member 10 to form a fillet weld joint structure.

Here, as shown in FIG. 2, only fillet welds 12, 12 along both long sides of the vertical member 11 are provided between the vertical member 11 and the horizontal member 10, respectively. However, the corner turning fillet welding is not applied. Moreover, in this case, the fillet welds 12 and 12 employ the so-called end stop bead type in which the weld bead is not extended outward from both short sides of the longitudinal member 11. The arrow a in FIG. 2 indicates the welding direction, and reference numeral 11
Each a indicates an unwelded portion.

As described above, by adopting the end stop bead type fillet welding, as compared with the case of the extended bead type welding man-hour,
The welding time can be shortened and the weight corresponding to the extension bead can be reduced. Further, since the corner turning fillet welding is not performed, the stress concentration associated with the corner turning fillet welding can be eliminated as in the case of the fillet welded joint structure shown in FIGS.

Further, in the vicinity of each toe of the fillet welds 12, 12, as shown in FIG. 3, the welding bead is formed in a sectional shape of a concave curve 12a which smoothly connects to the adjacent surface, whereby the corner is formed. It is possible to reduce the stress concentration at the toes of the meat welds 12, 12.

Furthermore, as shown in FIGS. 1 and 2, a protruding portion 12b that protrudes slightly outward is formed at each toe of the weld bead of the side fillet welds 12, 12, and the protrusions 12b are formed in the vertical direction. It is not a straight line that matches the short side of the member 11.
With this configuration, it is possible to reduce the stress concentration at the toe of the weld bead. The protruding portion 12b is naturally formed by performing the fillet welding without using the contact plate at the toe portion during the fillet welding operation.
There is no increase in man-hours due to the formation of 12b.

If it is necessary to form the toe of the welding beam on the same straight line as the short side of the longitudinal member 1 in order to improve the appearance, a padding material is provided at the toe. Then, fillet welding should be performed.

As described above, in the fillet welded joint structure of this embodiment, the longitudinal member 11 such as a face member with a longitudinal member is formed orthogonally to the lateral member 10 such as the slot / web stiffener of the hull structural member. The fillet welded joint structure formed by welding has fillet welds 12, 12 along the long sides on both sides of the lateral member 11.
1 only (therefore, the corner turning fillet weld 4 in FIG. 7 is not applied), and the fillet weld 1
Since 2 and 12 are of the end-stop bead type, it is possible to reduce the stress concentration generated in the welded portion of each structural member.

Further, since the cross section of the weld bead is formed in the shape of a smooth curve near the toe, the stress concentration at each weld toe of the transverse member 11 and the longitudinal member 10 should be relaxed. According to the experimental results, a fillet welded joint structure having a fatigue strength about twice that of the fillet welded joint structure shown in FIG. 7 could be obtained. Also,
From the viewpoint of fatigue strength, it was also found by experiments that it is almost equivalent to the fillet welded joint structure shown in FIGS. Needless to say, the number of steps can be reduced as compared with the fillet welded joint structure shown in FIGS.

Needless to say, the fillet welded joint structure of the present invention can be applied to each fillet welded joint structure in the hull structure of a ship. As an example, the slot web stiffener shown in FIG. The structure and a fillet welded joint structure in which this is welded to a flange material with a longe can be mentioned. In addition, the present invention can be applied to a general welded joint structure formed by interposing right-angled triangular brackets between mutually orthogonal hull members, or each welded joint structure in a scallop structure.

By the way, there are about 20,000 fillet welded joint structures on large merchant ships, and when all of them are constructed by manual welding, by adopting the structure of this embodiment, about 2,
200 hours working time can be shortened. Also in the case of the engine room alone, the work time can be shortened by about 100 hours due to the reduction of man-hours due to the adoption of corner turning fillet welding with about 900 members.

Further, in robot welding, there is a problem in accuracy and quality in corner turning fillet welding. In this embodiment, however, since corner turning fillet welding is not performed, fillet welded joint structure by robot welding is used. It is possible to improve quality and accuracy. Further, the weight of the welding bead can be reduced by the length of the welding bead, which is advantageous especially in the case of a high-speed ship.

[0022]

As described in detail above, according to the fillet welded joint structure of the present invention, the following effects and advantages are obtained. (1) By not performing corner-turning fillet welding in the conventional fillet welded joint structure, stress concentration generated in the welded part of the structural member can be reduced, which results in a fillet welded joint structure with high fatigue strength. can get. (2) By not providing an extension bead in the conventional fillet welded joint structure, it is possible to reduce man-hours and weight. (3) Due to the above (1) and (2), a fillet welded joint structure having a large fatigue strength can be obtained at a low manufacturing cost. (4) It is possible to improve accuracy and quality when adopting a welding robot.

[Brief description of drawings]

FIG. 1 is a side view of a fillet welded joint structure as an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a sectional view taken along the line BB of FIG.

FIG. 4 is a side view of a conventional fillet welded joint structure.

FIG. 5 is an enlarged side view of the relevant part.

6 is a sectional view taken along the line CC of FIG.

7 is a cross-sectional view taken along the line DD of FIG.

FIG. 8 is a side view of another conventional fillet welded joint structure.

9 is a cross-sectional view taken along the line EE of FIG.

FIG. 10 is a cross-sectional view corresponding to FIG. 9 of the modified example.

[Explanation of symbols]

 1 slot / web stiffener 1a unwelded part 2 face material with longue 3 fillet weld 3a extended bead 4 corner turning fillet weld 5 side end 10 lateral member as first structural member 11 longitudinal direction as second structural member Member 11a Unwelded part 11b End edge 12 Fillet weld 12a Smooth curve 12b Projection

Claims (3)

[Claims] 1. A fillet welded joint structure comprising a first structural member and a second structural member that are welded at substantially right angles to each other, and the second structural member has an end edge portion of which is an end-stop bead type fillet. A fillet welded joint structure, which is welded to the first structural member by welding. 2. The fillet weld joint structure according to claim 1, wherein in order to reduce stress concentration at the toe part of the end stop bead type fillet weld, the weld bead of the same weld is formed near the toe part. A fillet welded joint structure, characterized in that it is formed in a cross-sectional shape of a concave curve that smoothly connects to adjacent surfaces. 3. The fillet welded joint structure according to claim 1 or 2, wherein an end edge portion of the second structural member is formed in a substantially rectangular cross-sectional shape, and the end stop bead type fillet weld is performed at the end. A fillet welded joint, which is constructed along the long side of the edge, and at the toe of the weld, a slight protrusion to the outside of the welding beam of the weld is formed. Construction.