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AC/OX CUTTING/WELDING/BRAZING

Leftward welding

When the filler rod is held in front of the torch in the welding direction, this is called leftward welding. The welding flame points away from the finished weld. Leftward welding is used for sheet thicknesses up to 3–4 mm and for thinwalled pipes. When welding cast iron and non-ferrous metals, such as aluminium and brass, always weld leftward. Brazing should also be performed using this technique.

Vertical leftward welding Sheet steel up to 2.5 mm thick can be welded by vertical leftward welding.

Horizontal leftward welding Adjust the equipment for the correct flame. Move the torch with a slight rotational movement to melt both edges of the workpiece. Do not hold the torch too far away from the workpiece. (The core of the flame should be 2-3 mm from the workpiece). When the material begins to melt, feed the filler rod into the weld pool with small movements, and welding is in process. Make sure to find the right speed. The metal on each side of the seam must melt before the filler rod is fed into the weld pool.

Weld in the same manner as for horizontal welding.

Vertical leftward welding, filler rod angles:

5.01

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Material thickness 1.0–1.5 mm 30° Material thickness 1.5–3.0 mm 30°–60°