Flux shielded metal arc welding process principle

In the flux shielded metal arc welding process coalescence is produced from the electric arc. Here the electric arc is produced between the workpiece and the electrode. Here is to mention that the electrode is coated by flux to prevent oxide formation. In other other words the coating prevents contamination from the environment.
This coating also helps in performing stability and weld metal protection. The electrode also works as a filler material.

Principle of the process 

In this process heat needed for welding is obtained from the electric arc created between a coated electrode and the workpiece.  The arc temperature can be increased or decreased by employing higher or lower arc currents as a result the arc heat is also can be controlled. A high current with  a very small arc length can give very intense heat.
The arc melts the electrode and the job. Material from the filler rod or electrode are transferred to the job, through the arc and are deposited along the weld joint. The flux coating melts, produces a gaseous shield and slag to prevent atmospheric contamination of the molten metal.

Read :

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• Different Types of Welding Defects