Which welding process is generally not used in structural steel applications?

Oxy-acetylene welding is generally not used in structural steel applications primarily because it is not as suitable for the thicker materials commonly encountered in structural steelwork. This method relies on a combination of oxygen and acetylene gas to produce a flame that can melt metal, making it more appropriate for thinner materials or repair work rather than the robust connections and joints found in structural projects.

In contrast, MIG welding, TIG welding, and spot welding are all favored in structural applications due to their efficiency, speed, and ability to achieve strong welds on thicker sections of steel. MIG welding, for example, is often utilized for its high deposition rate and versatility, while TIG welding provides excellent control over the weld pool for critical applications. Spot welding is widely used for joining sheet metal components together, particularly in fabrication work. Thus, the distinct characteristics of oxy-acetylene welding limit its practical use in structural steel applications.