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AC/OX CUTTING/WELDING/BRAZING

Welding Techniques

After lighting the torch, adjust the flame until it has the characteristics required for the operation to be undertaken.

A normal flame is used for welding all types of steel, and copper. A flame with a slight surplus of Acetylene is used for welding Aluminium.

A flame with an excess of Oxygen is used for welding cast iron, brass, bronze and zinc alloys, and for brazing.

It is important to adjust welding flame correctly for the material to be welded. Flame types are given under the descriptions of the various filler materials.

Leftward welding

In gas welding, the joined edges of the workpiece melt and fuse, with or without filler material. Welding can be either leftward og rightward technique. The direction of weld is selected according to the thickness of the material. Rightward welding requires more expertise, and welders with limited experience are therefore recommended to use leftward welding, which is the simpler method. In either case, make sure that the weld penetrates completely and evenly on the reverse side of the material with no imperfections. NB. Correct alignment of the workpieces is essential to a good joint.

Rightward welding

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