JPH0366475A - Multiple nozzle gas shielded arc welding equipment - Google Patents

Abstract

PURPOSE:To economically perform efficient gas shielded arc welding having excellent external appearance and quality at high welding speed by providing >=2 kinds gas supply sources and forming a gas nozzle of a welding torch of multiple structure. CONSTITUTION:A gaseous carbon dioxide supply source 1 at low cost and a various mixed gas supply source 2 at high cost are arranged in parallel and connected with the welding torch 5. Gas is supplied in large quantities to an outer annular gap 16 of the tip nozzle 10 of the welding torch 5 from the gaseous carbon dioxide supply source 1 and carried like the arrow C to protect a weld zone from the air. The small quantity of gas is supplied like the arrow B to an inner annular gap 14 from the various mixed gas supply source 2 to perform welding at high speed. By this method, welding of good quality with high efficiency can be performed economically.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to gas shielded arc welding equipment.

[Conventional technology]

Gas shielded arc welding is typically classified into one type of gas, two types of mixed gas, and multi-type mixed gas, which is a mixture of three or more types of gas, depending on the shielding gas used. When typical shielding gases are evaluated in terms of cost, welding speed, and weld bead appearance, welding using one type of gas is inferior in welding speed and weld bead appearance, but the cost of the gas used is low.

On the other hand, welding using a mixed gas consisting of two or more types of inert shielding gases, such as He and Ar, allows for high-speed welding and provides an excellent weld bead appearance.
The cost of the shielding gas used is much higher than other welding methods.

As shown in FIG. 4, the nozzle of a welding torch used in conventional gas-shielded arc welding is equipped with a gas nozzle 20 so as to form an annular gap 21 around a contact tip 12 that supports a central core wire 11. When gas-shielded arc welding is performed, a sufficient amount of shielding gas to shield the arc D from the atmosphere is supplied through the annular gap 21 as shown by arrow E, and arc welding is performed while protecting the welding area.

[Problem to be solved by the invention]

As mentioned above, in gas shielded arc welding,
Since the shielding gas needs to protect the welding area by blocking the arc from the atmosphere, it must be shielded with a large amount of gas. Therefore, when performing efficient high-speed welding using a wide variety of mixed gases, the cost becomes extremely high.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a multi-nozzle gas shielded arc welding device that has good appearance quality and is capable of economically performing efficient gas shielded arc welding with a high welding speed. I have a purpose.

[Means to solve the problem]

In order to achieve the above object, the multi-nozzle gas shielded arc welding apparatus of the present invention uses a gas nozzle with a multiple structure, which has at least two or more types of shielding gas supply sources and has at least two or more shielding gas supply annular gaps in the welding torch. It is characterized by having the following.

[Effect]

According to the above configuration, since there are two or more types of gas supply sources and the gas nozzle of the welding torch has a multilayer structure, the shielding gas supplied to the inner circumferential gas nozzle and the outer circumferential gas nozzle is different in type. [Embodiment] Fig. 1 shows the overall configuration of a multi-nozzle gas-shielded arc welding apparatus of the present invention. A shielding gas supply source, such as a low-cost carbon dioxide (Cow) supply source 1, and a multi-species mixed gas that allows high-speed welding but is expensive, such as a four-component mixed gas (He+Ar+CO, +0,) supply source 2, are arranged in parallel. and is connected to a welding torch 5. There may be more of these shielding gas supply sources. Welding power source 3, wire feeding device 4, and welding torch 5 are connected to each other so as to satisfy their respective functions. Welding torch 5 shown in FIG.
A cross-sectional view of the nozzle 10 at the tip is shown in FIG.

A first gas nozzle 13 is attached to the outer periphery of the contact tip 12 that supports the central core wire 11 so as to form an inner annular gap 14 , and a second gas nozzle 15 is attached to the outer periphery of the first gas nozzle 13 to form an outer annular gap 16 . The annular gap has a double structure. There is no problem even if the number of these gas nozzles is increased and the annular gaps are multiplied.

Next, the effect will be explained. A large amount of gas is supplied from a carbon dioxide gas supply source 1 to the outer annular gap 16 and flows in the direction of arrow C to protect the welding area from the atmosphere. A small amount of gas is supplied to the inner annular gap 14 from the multi-mixed gas supply source 2 to the arc D as shown by the arrow B to perform high-speed welding.

〔Effect of the invention〕

As detailed above, in the present invention, two or more types of shielding gases are arranged and the welding torch is equipped with a gas nozzle that forms multiple annular gaps, so that different types of shielding gases can be separately supplied.

Therefore, by flowing a large amount of inexpensive gas into the annular gap on the outer periphery to isolate the welding area from the atmosphere, and flowing a small amount of expensive mixed gas into the annular gap on the inner periphery, high efficiency and high quality welding can be achieved. A multi-nozzle gas-shielded arc welding device that can economically perform the following steps is obtained.

[Brief explanation of drawings]

Figure 1.2 Overall configuration of the multi-nozzle gas-shielded arc welding device of the present invention. Figure 2: External appearance of the welding torch of the present invention.3 Factors 2. Cross-sectional view of the nozzle tip of the welding torch of the present invention.Figure 4 : Cross-sectional view of the tip nozzle of a conventional welding torch 1.2... Shielding gas supply source 3... Welding power source 4... Wire feeding device 5... Welding torch 10... Nozzle 11...Core wire 12...Contact tip 13...First gas nozzle 14...Inner annular gap 15...Second gas nozzle 16...Outer annular gap

Claims (1)

[Claims] A multi-nozzle gas shield for gas shield arc welding, characterized in that it has at least two or more different types of shielding gas supply sources, and a welding torch is equipped with a gas nozzle of a multiple structure having at least two or more shielding gas supply annular gaps. Arc welding equipment.