A METHOD OF OPTIMUM PURGING FOR CONVENTIONALROOT WELDING PROCESS OF FERRITIC CHROME MOLY STEEL PIPES

摘要

The invention relates to a method of welding ferritic chrome moly steel in butt joint root welding .The invented method having work piece (01)and (02) having edge prepared opening end of 30 degree to the horizontal axis with butt joint area. The gas flow movement arrested by full sealing sheet (06)and sealing sheet washer (09)with locking nut is pulled out with the sealing sheet puller (10) the metal end cover (03) with outlet valve (04) and inlet connector (05)with gas cylinder source (12) with control valve. The aluminum foil tape (11) which sticks to arrested the root gap 2mm turn maintained the preheat temperature with minimum 150° C ensure that the root purring with the optimum pressure ,flow and purity of the inert gas. The workspace (01) & (02) is ready to carry out the root welding uniformly for the work piece having outside diameter 610mm with thickness of 100mm seamless pipe of having specification ferritic chrome moly steel and weight of work piece is 9 tons /job.