Traditionally the welding of these two grades of duplex and superduplex stainless pipes in the offshore oil industry, has been carried out by using the Gas Tungsten Arc Welding (GTAW) process for thin wall pipes, and for thicker wall pipes, a combination of GTAW for the root run and the Shielded Metal Arc Welding (SMAW) process for the filling and capping layers.

These processes have given the fabricators low defect rates and satisfactory weld metal mechanical and corrosion properties. Their main drawback is the relatively slow welding speed, resulting in low productivity rates for the fabricators. With even more emphasis now being paid to improving welding productivity, attention has turned to the utilization of the more productive cored wires.

A survey of different welding procedures is presented, where the flux-cored arc welding process (FCAW) has been successfully applied for welding pipes in all positions on 22% Cr duplex and 25% Cr superduplex stainless pipes with wall thicknesses from 12mm up to 42mm.

The results indicates that the FCAW process offers good mechanical and corrosion properties in accordance with specifications given.