SU79775A1 - The method of automatic arc welding - Google Patents

Description

A method of automatic arc welding under the flux layer of sheets, in particular, high-alloy steel and non-ferrous metals (aluminum, copper, bronze, etc.), is proposed.

According to the invention, welding is carried out with a carbon electrode without feeding the filler metal into the arc zone.

The proposed method allows the welding of thin sheets, which is difficult to achieve when using a metal electrode. The welding quality is quite high, since the flux protects the alloyed metal from being alloyed. The method allows to obtain a high welding speed as compared to resistance welding. The welding equipment required to carry out the proposed method and the control of the welding process are simpler than with conventional welding under a layer of flux.

FIG. 1-3 depicts (in section) the mutual position of the electrode and the sheets to be welded when making various types of joints by welding according to the proposed method. FIG. 1 shows Szarka - istov with flanged edges.

A voltage is applied to the carbon electrode Y and the part to be welded 2 from the current source (DC weldingformer or AC apparatus). The welding area, surrounded by the flux-holding device 4, is filled with a flux layer 3. burns under a layer of flux. When an arc occurs, the relative displacement of the electrode and part at a constant speed for the selected current strength is given. Due to the heat generated during the arc burning, the edges of the product being welded melt and weld seam 3 is formed.

The molten flux forms a slag layer 6, covering the metal bath, which provides reliable protection against oxidation and nitration with oxygen and nitrogen in the air.

With this method of welding, the weld metal 5 gets a dense structure and high mechanical performance, the appearance of the weld has a smooth outline.

The arc under the flux layer burns steadily and is not required to maintain steady arc burning.

475

additional devices in the form of stabilizers, solenoids, eliminating the need for the introduction of paper cords into the arc to protect the molten metal from the action of atmospheric oxygen.

The electrode is carbon or graphite rods of circular cross section, specially prepared, without a wick, or cut from the waste electrodes of the melting electric furnaces (in the latter case, the electrodes may be rectangular).

Before welding, it is necessary to fill the electrode in such a way that the junction of the sheets (TIP in the corner (Figure 7,, done in the electrode).

For welding overlap sheets (Fig. 2) and the corner joint

(Fig. 3) it is necessary to collect the sheets so that there are no gaps between them. Before welding, the electrode is tucked into a cone. Most of the electrode should be under the overlap and a smaller part above the single sheet.

The welding process is carried out as follows. the same as for edge welding.

Subject invention

An automatic arc welding method under a flux layer, characterized in that welding is carried out with a carbon electrode without. filing filler material in the arc zone.