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COATED ELECTRODES

Types of electrodes

Electrodes for manual arc welding (sometimes referred to as stick welding) consist of a rod and a coating material. As a rule, the alloy in the rod will be similar to the material to be welded.

The rod forms part of the welding circuit, and when it is melted together with the coating material, it provides the filler which is necessary to obtain a welded joint.

The object of the electrode coating is to provide easy striking and a stable arc. The coating material also contains elements which affect the transport of metal across the arc and provide good mechanical and chemical properties to the alloy formed between the base material

and the rod core in the electrode. When molten, the coating also provides a gas shield around the molten pool, which acts as protection against the atmosphere during welding. The coating elements form a slag when cool which further protects the weld during the cooling down process. The coating may also contain substances (i.e. iron powder), which increase the metal depositing properties of the electrode during welding. Electrode size (2.5, 3.2, 4.0 mm etc.) indicates the diameter of the rod core.

Control of Recovery

By adding metal powder into the coating we can regulate the electrodes recovery (Deposition rate).

3.01 The coated electrode

Rod core grip end

Coating Electrode size

Rod core

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