JPH09253843A - Stress relieved weld bead structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the welding work, and improve the durability of a weld zone. SOLUTION: A weld bead structure is provided with a fillet bead part 3 on each side in which an end face 2a of a tilting plate 2 is abutted on one surface 1a of a base plate 1 and each side of the fitting plate is fillet welded, and an additional bead part 5 on each side in which the fillet bead part 3 is extended on the surface 1a of the base plate 1 from an end 2b of the fitting plate 2. The additional bead part 5 is extended by 10-40mm in an approximately straight manner simultaneously with the welding of the fillet bead part 3. Automation of the welding is facilitated by providing the bead shape to extend the welding in an approximately straight manner. The welding bead toe is farther from a high stress part in which defects are easily happened in the weld bead, and the durability of the weld zone is increased. Because no joint part of the bead is present, the quality of the welding is improved, and the weld bead part and the extended weld bead part are consistently and automatically welded to simplify the welding work.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding bead portion formed by welding one surface of one plate with an end surface of the other plate and filleting both sides thereof in the vicinity of the end of the other plate. Regarding bead structure.

[0002]

2. Description of the Related Art A conventional weld bead structure generally has a surface 1a of a base plate 1 and an end surface 2a of a mounting plate 2 as shown in FIG.
Are joined by forming fillet bead portion 3 by fillet welding, and so-called V winding welding is performed by performing so-called V winding welding so as to surround the end 2b of the mounting plate 2 from the end of the fillet bead portion 3. Was formed.

However, this V winding welding is performed by manual welding of the operator, while the fillet welding forming the fillet bead portion 3 is automatically performed by the welding machine, and therefore a consistent total welding is performed. The automatic welding cannot be performed and the work efficiency of the welding is reduced, the welding technique with high difficulty that can be done only by a skilled welder is required, and the bead is not formed in the connection portion 4a with the automatic welding portion 3 and the V-turn portion 4b. The shape is likely to collapse and a welding defect is likely to occur. Further, since these portions are in a high stress portion near the end portion due to the presence of the mounting plate 2, cracks and the like are easily generated. There have been various problems such as the fact that a part needs to be grinded and requires a great deal of working time, and that it is difficult to apply the coating and surface treatment is required depending on the case.

On the other hand, in order to partially solve the problem of V winding welding as described above, the fillet bead portion 3 is attached to the portion 2 of the mounting plate 2.
A welding method is also practiced, in which V winding welding is omitted by stopping before b and ending. However, with this method, the end of the weld bead, which is likely to cause defects, remains in the high stress portion of the end portion of the mounting plate 2, and therefore the problem that fatigue failure is likely to occur due to the defects cannot be solved.

Further, a welding method has been proposed in which the weld bead end is lifted upward to the upper plate (corresponding to the mounting plate 2 in FIG. 7) (see Japanese Patent Laid-Open No. 62-254973). However, such welding methods are limited to manual welding, stand-up welding is difficult in terms of welding technology, there is a weld end at a high stress point of the upper plate, and the plate joint is watertight. However, it has various problems such as not being used for welding internal structural parts such as tanks.

[0006]

The present invention solves the above problems in the prior art, and the invention of claim 1 or 2 enables consistent automatic welding and greatly simplifies welding work.
An object of the present invention is to provide a weld bead structure in which defects are less likely to occur and durability of a welded portion can be improved. The invention of claim 3 can be used for a portion requiring water tightness of a plate joint inside a tank or the like. An object is to provide a bead structure.

[0007]

In order to solve the above-mentioned problems, the present invention according to claim 1 provides a weld bead structure in which one end of one plate is abutted with the end face of the other plate and both sides thereof are formed. It has a weld bead portion on both sides formed by meat welding, and extended weld bead portions on both sides obtained by extending and welding the weld bead portions on both sides on the one surface from the end portion of the other plate. And

In addition to the above, the invention of claim 2 is characterized in that the extended weld bead portion is extended substantially linearly from the weld bead portion.

According to a third aspect of the present invention, in addition to the features of the first aspect, the one plate and the other end of the other plate are additionally welded between the extended weld bead portions on both sides. It is characterized by having the formed end weld bead portion.

[0010]

1 shows an example of a weld bead structure to which the present invention is applied. The weld bead structure is a fillet as weld bead portions on both sides formed by butting one surface 1a of the base plate 1 which is one plate with the end surface 2a of the mounting plate 2 which is the other plate and performing fillet welding on both sides thereof. It has a bead portion 3 and a waste bead portion 5 as an extended weld bead portion on both sides obtained by extending and welding the fillet bead portion 3 from one end 2b which is the end portion of the mounting plate 2 onto one surface 1a of the base plate 1. . The fillet bead portion 3 is formed by automatic fillet welding by an automatic welding machine in a ship or the like. The discarding bead portion 5 is automatically welded to the fillet bead portion 3 at the same time as the welding of the fillet bead portion 3 and linearly extended and welded, so that, for example, 10 mm to 4 mm.
It is formed to have a length of about 0 mm.

With such a weld bead structure, the base plate 1 and the mounting plate 2 can be fully automatically welded, and if automated, the welding work can be made extremely efficient and the fillet bead portion 3 can be welded.
Since there is no interruption or bead seam between the waste bead portion 5 and the waste bead portion 5, welding defects do not occur and high quality welding can be obtained. Further, since the weld toe does not exist at the stress concentrated portion or the high stress portion near the end 2b of the mounting plate 2 or in the vicinity thereof, fatigue fracture or the like is less likely to occur and long-life welding can be obtained. Furthermore, since it is a consistent automatic welding, there is no variation in the welding quality, and it is not necessary to finish the bead with a grinder or to perform a surface treatment, which simplifies the welding work and the grinder finishing work.

FIG. 2 shows another example of the weld bead structure to which the present invention is applied. Compared to the one shown in FIG.
The difference is that an end weld bead portion 6 formed by additionally welding the base plate 1 and the end 2b of the mounting plate 2 is provided between the waste bead portions 5 and 5 on both sides. With such a structure, since the entire periphery of the contact portion between the base plate 1 and the mounting plate 2 is sealed by welding, a watertight structure in which water or liquid does not enter the contact surface. Therefore, this weld bead structure is used, for example, in the internal structure part of a water tank or an oil tank of a ship. Since the end weld bead portion 6 is a straight line weld between the discarded bead portions 5 and 5, it is a welding having a much lower degree of difficulty than the V winding welding, and can be performed even by an inexperienced welding operator. It is a thing. Further, since it is a straight line welding, there is a possibility of applying automatic welding.

FIG. 3 shows an example in which the waste bead portion 5 is welded so as to be gradually separated from the center line 2c of the mounting plate 2.

FIG. 4 shows an example of the application place when the weld bead structure of the present invention is applied to the hull structure of a ship. (A)
(F) is a structure in which, for example, a transverse web 8 welded to the outer plate 7 of the ship is reinforced by a stiffener 9, and the end of the stiffener 9 intersects the face material 10a of the angle 10 to form the lug end portion. The structure formed, the structure in which the end of the stiffener 9 is reinforced by the bracket 11 when the load is large, for example, the angle 10 is set up on the back of the upper deck or the deck 12 in the engine room, and the stiffener 9 is placed between them. 2 shows a structure reinforced by 1., a structure having a slot 13 as a drain hole, and a structure having a scallop 14 as well.

In these structures, the plates and face materials of the respective parts are fillet-welded to each other as the base plate 1 and the mounting plate 2 shown in FIG. 1, and the waste bead parts 5 are attached respectively as shown in the drawing. In the hull structure of a ship, all of these weld bead structure parts are extremely large in number, and the total number is tens of thousands. Therefore, if the weld bead structure of the present invention is adopted, the work efficiency of hull construction is greatly improved, and labor saving and shortening of the construction period can be achieved. Further, stable high quality of the welded structure can be obtained.

FIG. 5 shows the result of a fatigue test on the structure of the snip end in order to compare the weld bead structure of the present invention shown in FIG. 1 with the conventional V-winding type weld bead structure, and FIG. The shape of the test piece that was used is shown. The test piece corresponds to the base plate 1 in FIG. 1, and in the plan view, (a) is a waste bead type having a waste bead portion 5 to which the present invention is applied and (c) is a conventional weld bead structure. It is a V-winding type having a V-winding welding bead portion 4. Each of them is a test piece having a length of 440 mm, a width of 100 mm, and a plate thickness of 10 mm, and a plate 15 assuming another member is erected and welded between the weld bead structures so as to be close to an actual application.

As shown in FIG. 5, several kinds of stress amplitudes were tested. At any stress amplitude, the waste bead type of the present invention shown by a solid line and a circle in the figure shows a conventional V type shown by a broken line and a triangle. Good results were obtained, in which the number of repetitions of stress amplitude until crack initiation and fracture was increased, and the fatigue life was extended, compared with the winding form. The numbers near the circles and triangles in the figure indicate the length (mm) of the crack at that time.

[0018]

As described above, according to the present invention, in the invention of claim 1, a weld bead structure is formed by fillet welding a base plate which is one plate and a mounting plate which is the other plate.
The weld bead on both sides formed by fillet welding and the extended weld bead on both sides intentionally extended to the place where there is no mounting plate are welded, so the weld bead is continuous and its toe is It can be moved away from the edge of the other plate. As a result, there are no interrupted points or joints in the weld bead where defects are likely to occur, and welding quality is improved. Further, by moving the weld bead toe away from the end portion of the other plate, the stress concentration portion in the vicinity thereof, and the high stress portion, the stress in this portion where defects are likely to occur can be reduced. As a result, the condition for fatigue fracture is improved and the life of the welded part is extended.

With the extension of the life of the end portion, it becomes unnecessary to finish the bead with a grinder to improve fatigue strength. Furthermore, since the weld bead portion and the extended weld bead portion can be consistently formed by automatic welding, the quality of welding is stabilized. In addition, since there is no need for manual welding such as the conventional V-winding welding and the need for grinder finishing, the welding work is greatly simplified, labor is saved, and the construction period is shortened. Particularly, in the hull structure of a ship, since there are innumerable fillet welded ends, the effects of the present invention as described above are more remarkably exhibited.

According to the second aspect of the invention, in addition to the above, the extended weld bead portions on both sides are extended substantially linearly from the weld bead portion, so that it is easier to consistently and automatically weld these portions. Become.

According to the third aspect of the present invention, since one plate and the end of the other plate are welded between the extended weld bead portions on both sides to form the end weld bead portion, the joint portion of both plates is joined. The entire circumference is sealed by welding, and the structure prevents water and liquid from entering the contact surfaces of both plates. As a result, the weld bead structure can be used, for example, in water tanks and oil tank parts of ships. In this case, this welding is a straight line welding between the extension welding bead portions, and is technically easier than conventional V winding welding. Therefore, the welding work can be facilitated and the welding time can be shortened. Further, since welding can be performed by an inexperienced worker, a skilled worker can be effectively utilized and the welding worker can be easily managed. Further, since it is straight line welding, there is a possibility of applying automatic welding.

[Brief description of drawings]

FIG. 1 shows an example of a weld bead structure to which the present invention is applied, in which (a) is a side view and (b) is a plan view.

FIG. 2 is a plan view showing another weld bead structure to which the present invention is applied.

FIG. 3 is a plan view showing still another weld bead structure to which the present invention is applied.

4 (a) to (f) are explanatory views of a structural portion of a ship to which the weld bead structure of the present invention is applied.

FIG. 5 is a curve diagram showing the results of a fatigue fracture test on a waste bead type to which the present invention is applied as a weld bead structure and a conventional V-winding type.

FIG. 6 shows the shape of the test piece used in the above test,
(A) is a plan view of a discarded bead type, (b) is a side view thereof,
(C) is a plan view of the V-winding type, and (d) is a side view thereof.

FIG. 7 shows an example of a conventional weld bead structure, (a) is a side view and (b) is a plan view.

[Explanation of symbols]

 1 Base plate (one plate) 1a One surface 2 Mounting plate (other plate) 2a End surface 2b End (end part) 3 Fillet bead part (welding bead part) 5 Discarded bead part (extended welding bead part) 6 End part welding Bead part

Front page continuation (72) Inventor Akio Murakami 3-1, 1-1 Higashikawasaki-cho, Chuo-ku, Kobe-shi, Hyogo Inside Kawasaki Heavy Industries, Ltd. (72) Inventor Hideaki Naoi 3-chome, Higashi-kawasaki-cho, Chuo-ku, Kobe-shi, Hyogo No. 1 Kawasaki Heavy Industries Ltd. Kobe factory

Claims (3)

[Claims] 1. A weld bead portion on both sides formed by abutting one surface of one plate with an end surface of the other plate and filleting both sides thereof, and both sides from the end of the other plate to the one surface. A weld bead structure having extended weld bead portions on both sides obtained by extending and welding the weld bead portion of. 2. The weld bead structure according to claim 1, wherein the extended weld bead portion extends substantially linearly from the weld bead portion. 3. An end weld bead portion formed by additionally welding the one plate and the end portion of the other plate between the extension weld bead portions on both sides. The weld bead structure according to 1.