Discussion on Weld Repair of Small-sized SAW Steel Pipes

Addressing the problems relating to the single-side welding and dual-side formation weld repair of small-sized SAW steel pipes such as poor weld seam quality and tendency of internally overlapping,a newly- developed weld repair process is used by Huabei Petroleum Steel Pipe Plant for producing Φ355.6 mm×5.6 mm SAW pipe in steel grade L360MB. The said process involves ceramic lining + prime CO₂ gas shielded welding + filling and covering with CO₂ gas shielded welding（manual electric arc welding）. Thanks to employment of this weld repair process,the weld-repaired seam is well formed and free of inner overlap,and possesses good mechanical properties,and the quality is up to relevant requirements of applicable standard.