Shielded metal arc welding (SMAW) is the simplest, least expensive, and mostly widely used arc welding process. It is often referred to as ‘stick welding’ or manual metal arc welding. This process produces coalescence of metals by heating them with an arc between a covered metal electrode and the base metal work piece. Shielding is provided by decomposition of the electrode covering. The main function of the shielding is to protect the arc and the hot metal from chemical reaction with constituents of the atmosphere. The electrode covering contains fluxing agents, scavengers, and slag formers (1). Pressure is not used in the process, and the filler metal is obtained from the electrode. All ferrous metals can be welded in all positions using SMAW.
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