The surfaces of the workpieces are positioned end-to-end. As a rule, flash-butt welding is subdivided into preheating, flashing and upsetting. Preheating is carried out under low welding pressure. Once the welding joint is heated, flashing commences and joint surface material is burnt off, resulting in even joint surface. After arriving at preset flashing loss, upsetting commences, resulting in an irregular "fin" on the surface of the upset metal consisting of molten and oxidized material.
Examples of flash-butt weldable items: rod stock, chains, rails and pipes.