Abstract: A welding arrangement (5, 23) for welding pipe sections (6, 7) comprises a power supplying and gas supplying unit (7, 24), a welding unit operatively connected to the power supplying and gas supplying unit and adapted at least in part to displace about the circumference of the pipe (6, 7) during the welding operation, and means whereby the power and gas are transmitted to the welding unit through a transmitting ring (8, 27) sufficient in diameter to extend around the pipe (6, 7) during the welding operation and thereby enabling the power and gas supply unit (7, 24) to remain stationary during the welding operation.