JPH0318474A - Method for welding sheet at high speed - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a high-speed welding method for thin plates, particularly those having a thickness of 0.8 to 2.0 mm.

[Prior Art] When welding thin plates by consumable electrode arc welding, when automatic groove tracing control is performed using an arc sensor, the minimum plate thickness is 2 mm and the maximum welding speed is 0.9 m/min.

Such limitations are thought to be due to the following problems in welding thin plates.

■When welding thin plates, the bead width is naturally small, so a slight deviation in the aiming position of the welding torch or deformation of the welded material can immediately lead to welding defects.

■In particular, in welding without weaving, arc pressure and heat input are concentrated directly below the arc, so penetration is concentrated in the center.
For this reason, it is difficult to obtain a smooth bead shape, and a phenomenon called so-called strike-through, punch-through, or burn-through occurs.

■ High-speed welding is extremely difficult because the welding current cannot be increased due to the restriction that the penetration depth must be smaller than the plate thickness.

On the other hand, a method using an arc sensor for groove tracing control technology in automatic arc welding is known. No. 174270/1983).

Automatic bevel tracing control using the arc sensor method is indispensable and extremely effective in solving the above-mentioned problems in welding thin plates. However, it is 10 Hz, and increasing the rocking speed beyond that is mechanically difficult and is actually impossible. For this reason, the welding speed is also lm/
It is impossible to achieve anything beyond that.

[Problems to be Solved by the Invention] However, it is thought that the high-speed rotation type arc sensor method can easily solve the problems in the swing type as described above. However, even in this case, unlike welding of thick plates, 1
Setting welding conditions is difficult because welding must be carried out using a bus, at high speed, and with high precision.

As a result of welding experiments on thin plates, the present invention has discovered appropriate welding conditions, and an object of the present invention is to provide a high-speed welding method for thin plates based on this knowledge.

[Means for Solving the Problems] The method for high-speed welding of thin plates according to the present invention provides a method for welding thin plates having a thickness of 0.8 to 2.
When welding a thin plate of 0 mm in thickness, a high-speed rotating arc sensor with an arc rotation speed N of 10 to 150 Hz and an arc rotation diameter D of 0.5 to 3.0 mm is used to weld the bevel. While performing automatic tracing control,
Welding current 150-400A, welding speed 1.5-3.0
Welding was carried out under conditions of m/min.

[Function] According to the high-speed rotating arc welding method, the rotational speed of the arc can be easily increased, and the arc sensor can be controlled to automatically follow the weld line of the overlapped portion of thin plates. , the positional deviation of the welding torch can be precisely controlled. Furthermore, since the arc pressure and heat input are dispersed by the rotation of the arc, the penetration is not concentrated in the center, and the overall bead shape is improved to be shallower and broader, and the bead surface shape is also smoother. Therefore, since the penetration becomes substantially shallower, the welding current can be increased and the welding speed becomes faster.

[Example code] Specific examples will be described below.

1) The material of the test material is mild steel, and the plate thickness is 0.8, 1. 0.1.4,
Five types were used, 1.6 and 2.0 mm, and lap joint welding was performed between thin plates of the same thickness.

(2> Welding method As schematically shown in Figure 1, lap joint welding was performed while automatically tracing the welding line 10 using a rotating arc sensor. In the figure, 1 is a welding torch, its rotation speed N is detected by a rotation detector (not shown). 2 is a motor for rotating the torch 1, which is rotated via a gear mechanism 3.

Reference numeral 4 denotes a welding wire that is automatically fed to the eccentric position of the torch 1. Several types of torches 1 with different eccentric distances are prepared, and by replacing this, the rotational diameter D of the arc 5 is changed. 6 is a bead, and 7 is a thin plate which is a material to be welded. In addition,
Although not shown, the torch 1 includes an X-axis moving mechanism that moves the torch 1 in a direction perpendicular to the welding line 10, and a torch 1
It is supported by a y-axis moving mechanism that moves it in the height direction. Further, a constant current power source was used as the welding power source, and welding was performed in a mixed gas atmosphere of A' and CO2.

Furthermore, the welding length was set to 500 mm, which is the same for all test materials.

(3) Test results The welding conditions and test results are as shown in Table 1.

[Effects of the Invention] As described above, according to the present invention, a thin plate having a thickness of 0.8 to 2.0 mm could be welded at high speed by the rotary arc sensor method.

[Brief explanation of drawings] FIG. 1 is an explanatory diagram of the rotary arc sensor method. 1...Welding torch 2...Rotation motor 3...Gear mechanism 4...Welding wire 5...Arc 6...bead 7... Thin plate (base material) 10...Welding line

Claims (1)

[Claims] When welding thin plates with a thickness of 0.8 to 2.0 mm, the arc sensor can be welded using a high-speed rotating arc welding method with an arc rotation speed of 10 to 150 Hz and an arc rotation diameter of 0.5 to 3.0 mm. Welding current is 150 to 400 A and welding speed is 1.5 to 3.
A method for high-speed welding of thin plates, characterized by welding under conditions of 0 m/min.