JP2001246466A - Welding method for steel plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease the amount of spatters when welding after forming a through-hole for welding in one plate out of two overlapped plates. SOLUTION: In a welding method for the plates 1, 2, in which the through- hole 1a for welding is formed in one of the two plates 1, 2 arranged after making parts to be welded come into contact with each other and a contact part between the adjacent part of the inner periphery of the through-hole 1a for the above welding of the above one plate 1 and the other plate 2, is welded from the above plate 1 side, the above through-hole 1a for welding is formed to have a minor axis and a major axis, and parts in plural places separated from each other in the above minor axis direction of the above through-hole 1a for welding of the above plate 1 on the one side is welded to the contact parts A1, A1 with the other plate 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for forming a through hole for welding in one of two steel plates in which a portion to be welded is brought into contact with the other steel plate, and forming the through hole for welding of the one steel plate. The present invention relates to a method for welding a steel sheet in which a contact portion between an inner peripheral portion of a hole and the other steel sheet is welded from the one steel sheet side, and more particularly to a method for welding a steel sheet capable of reducing generation of spatter during the welding. . The welding method of the present invention can be used in an arc welding method or the like. Further, it can be used when manufacturing a frame of an image forming apparatus such as a copying machine or a printer, a frame of an OA device, or the like.

[0002]

2. Description of the Related Art FIG. 7 is an explanatory view of a conventional arc welding method, FIG. 7A is an explanatory view of butt welding, and FIG. 7B is an explanatory view of fillet welding. Conventionally, in arc welding such as plasma arc welding or TIG welding, a method shown in FIG. 7 has been known as a method of melting and joining a base material. In the butt welding in which the steel plates 01 and 02 in FIG. 7A are butt-welded to each other, there is a problem that when the thin plates are welded, the bonding surfaces are easily melted. In the fillet welding in which the end surface of the steel material 04 is brought into contact with and welded to the surface of the steel material 03 in FIG. 7B,
It may be difficult to secure a space for inserting a welding torch.

FIG. 8 is an explanatory view of plug welding in which a plug hole is formed and welded in one of two superposed steel sheets.
A is a plan view, and FIG. 8B is a side view. In FIG. 8, two steel plates 0 where the portions to be welded are brought into contact are arranged.
A plug hole (circular welding through hole) 01a is formed on one steel sheet 01 side of the first and second steel plates 01, 02, and a portion adjacent to the inner periphery of the welding through hole 01a of the one steel sheet 01 and the other steel sheet. Are welded by a torch (not shown) arranged on the one steel plate side. Since the two pieces of plug welding shown in FIG. 8 are overlapped with each other, the total plate thickness is increased, and it is possible to prevent burnout of the joint surface. In addition, the welding torch approach is easy, and the working time can be reduced for both manual welding and automatic welding.

[0004]

FIG. 9 is an explanatory view of the problem of the conventional welding method shown in FIG. 8; FIG. 9A is an explanatory view when the welding area is small, and FIG. 9B is an explanatory view when the welding area is large. FIG. In FIG. 9A, a welding area is indicated by A, and a welding portion A1 in the welding area A is a steel sheet 0 before welding.
1 and 2 show a contacted portion (a welded portion of a contact portion). If the area of the welding portion A1 is small, the welding strength will be weak. In FIG. 9B, when the welding time or the heat input is increased to increase the welding strength and the welding portion A1 is increased, there is a problem that thermal distortion increases.

If the diameter of the plug hole (through hole for welding) 01a is reduced, the plug hole is buried, making it impossible to visually determine whether or not welding is possible. Further, generation of spatter (metal vapor generated from metal melted during welding and blown up) increases. In particular, in the case of a galvanized steel sheet, zinc having a low melting point on the surface of the steel sheet is vaporized and blown out to the heat input side, and spatter increases. The spatter adheres to the steel sheet and drops during use as a product, which may adversely affect the performance of the product. Therefore, when the spatter is generated, it is necessary to wipe off the spatter adhered to the steel sheet after welding, and the productivity is deteriorated. Further, when the hole diameter of the plug hole (through hole for welding) 01a is increased, there is a problem that the overall rigidity is reduced, and the strength or the resonance frequency is reduced, so that resonance is easily caused by a low-frequency external force.

In view of the above circumstances, the present invention provides the following (O01)
To (O03). (O01) To reduce the amount of spatter generated during welding by forming a welding through hole in one of the two superposed steel sheets. (O02) To increase the welding strength when welding by forming a welding through hole in one of the two superposed steel sheets. (O03) To prevent a decrease in rigidity due to the formation of the welding through hole when forming a welding through hole in one of the two superposed steel sheets and performing welding.

[0007]

Means for Solving the Problems Next, the present invention for solving the above-mentioned problems will be described. Elements of the present invention are described in order to facilitate correspondence with the elements of the embodiments described later. The sign of parentheses is added in parentheses. The reason why the present invention is described in correspondence with the reference numerals of the following embodiments is to facilitate understanding of the present invention, and not to limit the scope of the present invention to the embodiments.

(First Invention) In order to solve the above-mentioned problems, a method for welding a steel sheet according to a first invention is a method for welding one of two steel sheets (1, 2) in which portions to be welded are brought into contact with each other. A welding through hole (1a) is formed in a steel plate (1), and a contact portion between an adjacent portion of the inner periphery of the welding through hole (1a) of the one steel plate (1) and the other steel plate (2) is formed. In the method for welding a steel plate (1, 2) to be welded from the one steel plate (1) side, the welding through hole (1a) is formed into a shape having a short diameter and a long diameter, and the one steel plate (1) is formed. It is characterized in that the contact portions (A1, A1) between the plurality of portions of the welding through hole (1a) separated in the minor diameter direction and the other steel plate (2) are welded.

(Operation of the First Invention)
In the method for welding a steel sheet according to the invention, a welding through hole (1a) is formed in one steel sheet (1) of two steel sheets (1, 2) in which portions to be welded are arranged in contact with each other. A contact portion between the inner peripheral portion of the welding through hole (1a) of one steel plate (1) and the other steel plate (2) is welded from the one steel plate (1) side. The welding through-hole (1a) is formed in a shape having a minor axis and a major axis, and a plurality of portions of the one steel plate (1) separated from each other in the minor-axis direction of the welding through-hole (1a). The contact portions (A1, A1) with the other steel plate (2) are welded. In the first invention, since the steel plate (1, 2) is welded at a plurality of locations separated in the minor diameter direction of the welding through hole (1a), the welding through hole (1) is welded.
The welding strength (separation resistance of the two steel plates) is greater than when welding is performed at one portion along the inner circumference in a).

Further, since the welding through-hole (1a) is not circular, but has a shape having a minor axis and a major axis, the dimension in the minor axis direction is smaller than the circular diameter when the welding through-hole is circular. can do. For this reason, the through hole (1a) of the welded portion does not become unnecessarily large.
It is possible to prevent the rigidity of the welding member obtained by welding 2) from being greatly reduced. In addition, the welding through hole (1)
a) Spaces at both ends in the major axis direction serve as escape paths for gas and melt generated during welding work, and thus spatter can be reduced.

(Second invention) A method for welding a steel sheet according to a second invention is a method for welding a steel sheet (1) of one of two steel sheets (1, 2) arranged in contact with a portion to be welded. A through hole (1a) is formed, and a contact portion between an inner peripheral portion of the one steel plate (1) and an inner peripheral portion of the welding through hole (1a) and the other steel plate (2) is connected to the one steel plate (1). The other steel plate (2) in the method for welding steel plates (1, 2) to be welded from the other.
The welding is performed in a state where a small-diameter spatter preventing through-hole (2a) communicating with the welding through-hole (1) is formed.

(Operation of the Second Invention)
In the method for welding a steel sheet according to the invention, a welding through hole (1a) is formed in one steel sheet (1) of two steel sheets (1, 2) in which portions to be welded are arranged in contact with each other. A contact portion between the inner peripheral portion of the welding through hole (1a) of one steel plate (1) and the other steel plate (2) is welded from the one steel plate (1) side. Since the other steel plate (2) is welded in a state where a small-diameter spatter preventing through hole (2a) communicating with the welding through hole (1) is formed, gas generated at the time of welding causes the spatter preventing through hole to pass through. Since (2a) is eliminated, the occurrence of spatter can be reduced.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments Next, specific examples (embodiments) of the embodiment of the laser welding method for a steel sheet according to the present invention will be described with reference to the drawings, but the present invention is limited to the following embodiments. It is not something to be done. (Embodiment 1) FIG. 1 is an explanatory view of a steel sheet used in an arc welding method for a steel sheet according to Embodiment 1 of the present invention. FIG. 1A is a plan view, and FIG. 1B is a cross-sectional view taken along the line IB-IB of FIG. 1A. . FIG. 2 is a view showing a state in which arc welding of the first embodiment is performed. FIG. 3 is an explanatory view of a welded portion welded by arc welding.
3B is a plan view, and FIG. 3B is a sectional view taken along the line IIIB-IIIB in FIG. 3A. 1 to 3, the steel plate 1 and the steel plate 2 are overlapped, and the steel plate 1 has an oblong plug hole (through hole for welding) 1a.

In FIG. 2, the steel plates 1 and 2 are connected to the anode, the electrode bar T is connected to the cathode, and an arc is generated between the steel plates 1 and 2 and the electrode bar T. When the steel plates 1 and 2 are melted, the steel plates 1 and 2 are welded. In FIG. 3, a welding area A includes a metal (the steel sheet 1,
2) is a solidified part. 2 of the welding area A
Regions A1 and A1 surrounded by a chain line are portions where the steel plates 1 and 2 are melted and solidified (welded portions of the steel plates 1 and 2). That is, the welded portions A1 and A1 of the steel plates 1 and 2 are two portions separated in the minor axis direction of the plug hole 1a. Therefore, in the first embodiment, since the steel plates 1 and 2 are welded at two places separated in the minor axis direction of the plug hole 1a, a large welding strength can be obtained.

Further, a space remains at both ends in the major diameter direction of the plug hole 1a, and the space serves as an escape path for a gas and a melt generated at the time of welding work, so that spatter can be reduced. The greater the area of the welded portions A1 and A1 of the steel plates 1 and 2 shown in FIG. 3, the greater the weld strength. When the size of the welding region A is constant, the area increases as the minor diameter D1 of the plug hole 1a decreases. Therefore, it is preferable to make the minor diameter of the plug hole 1a smaller. However, when the thickness of the steel plate 1 is set to t from the viewpoint of ease of processing,
About 1.5 t is appropriate for D1. In addition, the plug hole 1a has a length such that the major axis D2 is longer than the major axis length of the welding area A so that an escape path for gas and melt generated during welding work can be formed. Further, since the shape of the plug hole (through-hole for welding) 1a is set as described above, it does not become larger than necessary. For this reason, it can prevent that the rigidity of the welding member which welded the steel plates 1 and 2 falls large.

(Embodiment 2) FIG. 4 is an explanatory view of Embodiment 2 of the method for welding steel sheets of the present invention. FIG. 4A is a plan view of a steel sheet used in the arc welding method for steel sheets of Embodiment 2, and FIG. FIG. 4A is a cross-sectional view taken along the line IVB-IVB of FIG. 4A, and FIG. Note that the second embodiment
In the description, the same reference numerals are given to the components corresponding to the components of the first embodiment, and the detailed description thereof will be omitted. In the second embodiment, a sputter-preventing through hole 2a is formed in the steel plate 2, and the through hole 2a is a circular hole having a diameter smaller than the short diameter of the plug hole 1a of the steel plate 1. In addition, the shape of the through hole 2a for preventing spatters is elliptical in addition to circular,
Various shapes such as a rectangle can be used, and the size may be any size as long as it functions as an escape path for gas such as evaporated metal generated during welding. In the second embodiment, the gas generated at the time of welding escapes from the spatter preventing through-hole 2a, so that the generation of spatter can be reduced to more than in the first embodiment.

(Embodiment 3) FIG. 5 is an explanatory view of a welded portion welded by the steel plate welding method of Embodiment 3 and corresponds to FIG. 3A of Embodiment 1 described above. In the description of the third embodiment, components corresponding to the components of the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. While the first embodiment has a circular welded portion, the third embodiment differs from the first embodiment in that the welded portion A has an elliptical shape. In other respects, the third embodiment is the same as the first embodiment. The elliptical welding portion A of the third embodiment is formed by moving a welding torch during welding. Example 3
Also, as in the first embodiment, the steel plate 1 and the steel plate 2 are welded at two places separated in the short diameter direction of the plug hole 1a, so that the same operation and effect as in the first embodiment can be obtained.

(Modifications) Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above-described embodiments, but falls within the scope of the present invention described in the appended claims. Thus, various changes can be made. Modified embodiments of the present invention will be exemplified below. (H01) The shape of the plug hole (through hole for welding) 1a is as follows.
Elliptical shapes, rectangular shapes, and the like can be adopted in addition to the shapes shown in the first to third embodiments. Further, it is also possible to adopt the shapes exemplified in FIGS. 6A to 6D. FIG. 6 is an explanatory view of a modified example of the shape of the plug hole (through hole for welding), and FIGS.
FIG. 6D is a diagram showing different shapes of the plug holes. The plug hole shown in FIG. 6A has two grooves formed outward from the circular hole, and FIG. 6B has four grooves formed. In FIG. 6C, two grooves are formed outward from the square hole, and in FIG. 6D, four grooves are formed. FIG.
A, In FIG. 6C, the portion where the steel plate is welded is divided into two places,
In FIG. 6B and FIG. 6D, there are four parts. The plug holes having these shapes also have the same operation as the first embodiment.

[0019]

The above-described method for welding a steel sheet according to the present invention has the following effects. (E01) The width of both ends in the major diameter direction of the welding through hole formed in one of the two stacked steel plates may be large enough to allow steam generated during welding to escape. it can. For this reason, it is possible to prevent a decrease in rigidity due to the formation of the welding through-hole. In addition, since steam generated during welding escapes from both ends of the welding through hole in the major diameter direction, spatter can be reduced. (E02) The welding strength is increased because a plurality of portions of the welding through hole formed in one of the two stacked steel plates that are separated in the minor diameter direction and a plurality of contact portions of the other steel plate are welded. Can be. (E03) Spatter can be reduced by forming a spatter preventing through hole communicating with the welding through hole.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a steel sheet used in an arc welding method for a steel sheet according to a first embodiment of the present invention. FIG. 1A is a plan view, FIG.
FIG. 2B is a sectional view taken along the line IB-IB of FIG. 1A.

FIG. 2 is a diagram showing a state in which arc welding according to the first embodiment is performed.

3 is an explanatory view of a welded portion welded by arc welding, FIG. 3A is a plan view, and FIG. 3B is IIIB-I of FIG. 3A.
It is IIB sectional drawing.

FIG. 4 is an explanatory view of Embodiment 2 of the steel sheet welding method of the present invention. FIG. 4A is a plan view of a steel sheet used in the arc welding method of the steel sheet of Embodiment 2, and FIG. IVB-I
FIG. 4C is a sectional view taken along the line VB, and FIG.

FIG. 5 is an explanatory diagram of a welded portion welded by the method for welding a steel plate according to the third embodiment, and is a diagram corresponding to FIG. 3A of the first embodiment.

FIG. 6 is an explanatory view of a modified example of the shape of the plug hole (through hole for welding), and FIGS. 6A to 6D are diagrams showing different shapes of the plug hole, respectively.

7 is an explanatory view of a conventional arc welding method, FIG. 7A is an explanatory view of butt welding, and FIG. 7B is an explanatory view of fillet welding.

FIG. 8 is an explanatory view of plug welding in which a plug hole is formed in one of two superposed steel plates and welded, and FIG.
Is a plan view and FIG. 8B is a side view.

9 is an explanatory view of the problem of the conventional welding method shown in FIG. 8; FIG. 9A is an explanatory view when the welding area is small, and FIG. 9B is an explanatory view when the welding area is large.

[Explanation of symbols]

1, 2 ... steel plate, 1a: through hole for welding, 2a: through hole for preventing spatter, A1, A1: a plurality of portions separated from each other in the short diameter direction of the through hole 1a for welding of the steel plate 1 and the other steel plate 2 The welding part of the contact part with.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Satoshi Maeda 2274 Hongo, Ebina-shi, Kanagawa F-term in Fuji Xerox Co., Ltd. (reference) 4E081 AA08 BA13 BA40 DA13

Claims (2)

[Claims] 1. A welding through hole is formed in one of two steel plates in which portions to be welded are brought into contact with each other, and the inner periphery of the welding through hole of the one steel plate is adjacent to the inner periphery of the welding through hole. In a method for welding a steel plate, in which a contact portion between the portion and the other steel plate is welded from the one steel plate side, the welding through hole is formed into a shape having a short diameter and a long diameter, and the one steel plate is used for the welding penetration. A method for welding a steel plate, comprising welding a plurality of portions of the hole separated in the minor diameter direction and a contact portion with another steel plate. 2. A welding through-hole is formed in one of two steel plates having portions to be welded in contact with each other, and an inner periphery of the welding through-hole of the one steel plate is adjacent to the inner periphery of the welding through-hole. In a method for welding a steel plate, in which a contact portion between the portion and the other steel plate is welded from the one steel plate side, welding is performed in a state where a small-diameter spatter prevention through hole communicating with the welding through hole is formed in the other steel plate. A method for welding steel sheets.