JPS61193784A - Upset butt welding method - Google Patents

Abstract

PURPOSE:To equalize the contact resistance in the first stage of welding, and to execute sufficiently homogeneous welding even in case when a contact area or a contact width of materials to be welded, by placing a metallic powder which is the same as or different from the materials to be welded, between the materials to be welded, and welding them. CONSTITUTION:When executing the welding, a placing base 4 is raised to a level of materials to be welded 1a, 1b, both the material are made to approach each other, and metallic powder of a necessary quantity is inserted and held. After the placing base 4 has been lowered, an electrode 2 is conducted electrically and an upset butt welding is executed. In this way, said materials are joined by only the metallic powder which is suitable for the materials to be welded, and its necessary quality is obtained.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention relates to an upset butt in which the ends of coiled materials to be welded are interconnected using metal powder of the same or different materials. This relates to a welding method.

(B) Prior art In recent years, in steel manufacturing lines, a method of splicing coils has been adopted as a pre-process of pickling lines and cold rolling lines (tandem mills) from the viewpoint of line continuity. - There is no particular problem when pouring shell material, but depending on the material, breakage may occur in the line, reducing efficiency and workability.
This has become a problem as it leads to a decrease in yield.

Butt resistance welding methods such as upset butt welding and flash welding are extremely efficient compared to normal arc welding. Among these, butt welding is more efficient than flash welding, and because it does not generate flash, it is also superior in terms of working environment.

However, unlike flat welding, butt welding involves welding in a short period of time, and the influence of contact resistance during the initial stage of welding is large.Also, when joining large areas or wide materials, uneven heat input occurs, so the input Areas with insufficient heat oxidize before welding, resulting in insufficient welding and resulting in poor engagement defects.

On the other hand, if you try to apply heat to a place where welding is insufficient,
Other parts become overheated and burn-through problems occur. Therefore.

Butt welding has limited applications.

In order to improve the adhesion of the materials to be welded, a method has been proposed in which resistance welding is performed by placing a glassy metal alloy on the surface of the materials to be welded (Japanese Patent Publication No. 1581/1981). However, this method does not disclose that the glassy metal alloy is a powder.

(c) Problems to be Solved by the Invention The problems to be solved by the present invention are to provide an upset/butt welding method that can make the joint strength of the welded part uniform when joining coils by welding. There is a particular thing.

B) Means for solving the problems The upset/butt welding method of the present invention solves the above problems by sandwiching a suitable metal powder, which may be the same as or different from the materials to be welded, between the materials to be welded. are doing.

(E) Example The upset butt welding method of the present invention, as shown in FIG.
Sprinkle metal powder 3 and press the art material.

The metal powder 3 is placed on a mounting table 4 that moves up and down,
It is supplied between the materials to be welded ta and ib.

The mounting table 4 is a piston lot 51 of the fluid pressure cylinder 5.
is fixed to the tip of the It is preferable to receive a tray 6 below the mounting table 4 to receive the ll-1:1 metal powder 3 from falling.

Instead of moving up and down, the mounting table 4 can move the materials to be welded 1a, ■b
It may be a mechanism that moves forward and backward in a horizontal direction.

During welding, the mounting table 4 is raised to the level of the materials to be welded [a] and 1b, the materials are brought close to each other, and the required amount of metal powder 3 is held between them. After lowering the mounting table 4, the electrode 2 is energized to perform upset butt welding.

In this way, welding can be performed using only metal powder suitable for the materials to be welded, and the required properties can be obtained without any problems.

Note that when the metal powder is heated, it evaporates and generates reducing gas, etc., creating a non-oxidizing atmosphere around it. for example,
Using an organic binder with adhesive strength such as high viscosity oil, phenol, or epoxy resin, apply the adhesive to one or both of the connection surfaces of the welded materials in advance, bring the art material close to it, and then apply the same method as above. It is also possible to perform energized upset welding.

In the method of the present invention, metal powder remains in the welded area depending on the welding conditions.
It is also possible to improve the performance of welded parts of materials that become brittle due to coarsening of ferrite grains (for example, high-silicon steel, ferritic stainless steel, etc.). For example, it is preferable to use a soft material for the metal powder in a hardening material, and to use a metal containing austenite former in a ferrite coarsening material.

The results of implementing the method of the present invention on a thin plate with a thickness of 3 mm are shown in the first example.
Shown in the table. For comparison, the case using the conventional method is also shown.

The main component compositions of the 3% Si material and Alloy 600 in Table 1 are shown in Tables 2 and 3. The performance of the welded part was evaluated by the cracking rate (%) in a bending test (2t).

Table 1 The particle diameter of the metal powder 30 used in the present invention is preferably 0.1 gourd or less. The reason is that the purpose is to stabilize the contact resistance, so if it exceeds 0.1 m.

This is because inserting powder creates a new cause of instability. Examples supporting this are shown in Table 4.

(f) Effects According to the method of the present invention, the contact resistance at the initial stage of welding is made uniform, so even when the contact area or width of the welded materials is large, sufficiently homogeneous welding can be performed. .

Especially when performing coil splicing in processes such as cold rolling, pickling, heat treatment, forge welding, and electric resistance welding.

It is effective to apply the method of the present invention.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the welding method of the present invention. la, lb: material to be welded 2: electrode 3: metal powder 4: mounting table 5: fluid pressure cylinder 6: tray (5 people in addition) Patent 1 (21) 2, Title of the invention Upset/butt welding method 6, Relationship with the case of the person making the amendment Patent applicant address name (211) Sumitomo Metal Industries, Ltd. 4, Attorney 6 Contents of the amendment 4. In lines 15 and 16 of page 4, correct "Atmosphere, e.g., . . . organic material with adhesive force" to "Atmosphere (e.g., . . . organic material with adhesive force)". . that's all

Claims (1)

[Claims] An upset characterized by welding by sandwiching appropriate metal powder, which may or may not be the same as the material to be welded, between the materials to be welded.
Butt welding method.