Renewed Opportunities for Girth Welding in High-Strength Pipelines

Self-shielded flux cored arc welding (FCAW-S) was invented in 1959 as an alternative to shielded metal arc welding (SMAW) to improve productivity and reduce cost. It was introduced as a semiautomatic tubular wire process with conventional equipment: a constant-voltage, direct current power supply; a wire welding gun; and a wire feeder. As shown in Fig. 1, the key difference between FCAW-S and other open-arc welding processes is the absence of shielding gas. FCAW-S employs an arc in air without the intended shieldin..