Manual Metal Arc 

MMA Manual Metal Arc – is a welding process in which a consumable electrode is used to lay down the weld. An electric current passes down the electrode and arcs across to the metals that are to be joined together. The arc melts the electrode and the metals to form the weld pool. MMA is also known as stick welding.

MMA welding generally uses coated electrodes. During welding, the coating or flux disintegrates, forming a gas which shields the weld and also slag which coats the surface of the weld pass. Both the gas and the slag prevent atmospheric contamination of the weld. The slag is chipped off on completion of the weld pass. The shielding by the flux gives rise to the acronym SMMA – Shielded Manual Metal Arc.

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