Electrogas welding (EGW) is a continuous vertical-position arc welding process developed in 1961 in which an arc is struck between a consumable electrode and the workpiece. A shielding gas is sometimes used, but pressure is not applied. A major difference between EGW and its cousin, electroslag welding, is that the arc in EGW is not extinguished but instead remains struck throughout the welding process. It is used to make square-groove welds for butt and t-joints, especially in the shipbuilding industry and in the construction of storage tanks.