JPS63174784A - Automatic arc welding method for thin part - Google Patents

Abstract

PURPOSE:To speed up welding by welding a work which is freely position- adjustably supported to a supporting device while controlling the welding by a memory device that the line to be welded of the work is in a required downgrade state and a relative positional relation with a torch attains a specific value. CONSTITUTION:The work W is supported to a supporting plate 1 and the tilting thereof is controlled by means of an X-axis supporting column 4 and a Y-axis supporting column 5. The work W is welded while the relative positional relation between the welding torch 9 and the work W and the angle of the work W are controlled to specific values. The downward angle of the work is preferably about 5-25 deg. with a horizontal plane. Welding at a high speed is permitted by this method.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for automatically arc welding thin-walled parts having at least two dimensions.

<Conventional technology> In general, so-called downward welding, in which the surface of the workpiece is welded while maintaining it in a horizontal state, is often used during automatic arc welding, except for items with extremely complex shapes or extremely large sizes. There is.

<Problems to be solved by the invention> However, in the downward welding described above, the maximum welding speed is regulated under the basic premise of reliably obtaining a good welding result, and therefore, it has been particularly desired in recent years. There was a problem in that it could not meet the need for faster welding work.

As a result of repeated research focusing on the above-mentioned problem, it has been found that apart from thick-walled objects, thin-walled objects can be welded at a higher speed than the above-mentioned downward welding.

That is, an object of the present invention is to provide a method for automatically arc welding thin-walled objects to be welded at high speed.

<Means for Solving the Problems> In order to achieve the above object, the method of the present invention supports a workpiece to be welded by a workpiece support device whose posture can be adjusted freely, and which is disposed above the workpiece. The welding torch and the workpiece support device are configured to be relatively movable in the X, Y, and Z directions, and the line to be welded is divided into a plurality of sections so that the line to be welded is in a desired downward slope with respect to a horizontal plane. The set position state of the workpiece support device for each section and the relative position state between the torch and the workpiece support device are stored in a storage device, and the welded line in a desired downhill state with respect to the horizontal plane is stored in the storage device. It features an automatic arc welding method for thin-walled parts.

<Examples> The present invention will be described in detail below with reference to illustrated examples.

In FIGS. 1 and 2, reference numeral 1 denotes a support plate for supporting the workpiece W to be welded, and suitable supports 2, 2. ... supports the workpiece W to be welded. Reference numeral 3 denotes a support column with a fixed height that is placed at an appropriate position on the support plate 1, for example, below the approximate center point A of the support plate 1. The support plate 1 is tiltably locked via a universal joint. 4 is an X-axis support column placed below point B located in the X1 direction with respect to point A of support plate 1, and 5 is placed below point C which is also located in the Y1 direction with respect to point A. As with the first support column 3, the Y-axis support columns 4 and 5 lock the support plate 1 in a tiltable manner via a universal joint. Also, the X-axis and Y-axis support columns 4 and 5
is configured to be able to move up and down in the Z direction by a drive device (not shown) such as an electric motor or a pressure response device, and its adjusted position is detected by a position detector 6.7. The position detector 6.7 may be a potentiometer, a differential transformer, or the like that detects the adjusted position of the support column 4.5 in an analog manner, or may be an encoder that converts the amount of adjustment into a digital signal. 1 to 7 above constitute a workpiece support device 8 for supporting the workpiece W to be welded in an adjustable manner. Reference numeral 9 denotes a welding torch disposed above the workpiece W. This welding torch 9 and the workpiece support device 8 are configured to be relatively movable in the X, Y and two directions. It is supported movably in X, Y and two directions by an appropriate moving mechanism (not shown).

Now, if the workpiece W to be welded is a flat plate and the ττ line, I: line, and S line are straight lines, first, the point opening is in a downward position and the straight line ττ is inclined at an α angle with respect to the horizontal plane. Adjust the height of the support pillars 4 and 5 or 5, and store the set position state of the support pillar 4.5 in the storage device.At the same time, the position state of the welding torch 9 corresponding to the inclined straight line is stored. are also stored in the storage device.After this, the same adjustments as above are made for the sections r and s in order,
The positional state of each support column 4.5 and welding torch 9 is stored in a storage device.

During welding, welding parts I to I are sequentially welded based on the memory in the storage device. In this case, welding is performed in a so-called downhill state, where the weld line is inclined by an angle a with respect to the horizontal plane.

By the way, the thin-walled objects to be welded that are the object of the present invention are approximately several inches thick. This is because in the case of so-called thick walls, which are repeated more than 10 times, asymmetric beads, so-called humping beads, appear as the amount of molten metal increases. However, even in the case of thin walls, welding conditions for around 1 cod and around 7 to 9 cm cannot be considered the same because the welding conditions are different.
The angle a with respect to the horizontal plane can be approximately selected to be approximately 5 to 25 degrees.

In addition, if the line to be welded is a suitable curve or a combination of a curve and a straight line, a considerable margin is allowed for the angle α with respect to the horizontal plane, so the curved part is divided into multiple sections as appropriate, The inclination state of the welded object can be made constant during welding of at least a single section. Further, by making the sections finer, welding can be performed continuously or in a substantially continuous state. Of course, by making the entire workpiece support device 8 movable up and down, it is possible to compensate for the height of the welding position due to a change in the inclination direction of the support plate 1.

Further, it is preferable that the welding torch 9 has a variable setting angle using an appropriate mechanism. Furthermore, as the work supporting device 8, a so-called industrial robot whose hand position can be freely set can be employed.

In addition, if the shape and mounting position of the workpiece to be welded are known in advance, the setting position of the workpiece support device in each category and the relative positional state of the welding torch and the workpiece support device are stored as numerical data. Alternatively, a fixed electrical sequence control device can be used as a storage device.

<Effects of the Invention> As is clear from the above explanation, the welding method of the present invention automatically arc welds a thin welded part in a desired downward slope with respect to a horizontal plane by storing it in a storage device. The speed can be increased by 1.3 to 1.6 times compared to conventional downward welding, and almost the same welding results as downward welding can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional front view for explaining the present invention in detail, and FIG. 2 is a schematic plan view of FIG. 1.

Claims (1)

[Claims] 1. The workpiece is supported by a workpiece support device so that its posture can be adjusted, and the welding torch disposed above the workpiece and the workpiece support device are configured to be relatively movable in the X, Y, and Z directions. The line to be welded is divided into a plurality of sections so that the line to be welded is in a desired downhill state with respect to the horizontal plane, and the setting position of the workpiece support device for each section and the relative position of the torch and the workpiece support device are determined. An automatic arc welding method for thin-walled parts, in which the state is stored in a storage device, and a line to be welded in a desired downhill state relative to a horizontal plane is arc welded based on the storage in the storage device.