Abstract: A purge ring is provided for supplying a shield gas to the root side of a tubular article to be welded. The purge ring includes a generally U-shaped split-cylindrical body having an adjustable circumference together with slotted side walls connected by a bottom wall, the slotted side and bottom walls defining an isolation zone and a slip joint for insertion or retrieval of the purge ring in relation to the tubular article to be welded.