Quality inspection and defect analysis of girth weld in oil and gas long-distance pipeline

Abstract

To find out the causes of the girth weld defects in pipeline inspection and verify the weld quality, this paper implements the methods of radiographic inspection, mechanical inspection, and metallographic inspection to carry out experimental tests. The results show that the girth weld has good tensile property, poor impact toughness, reasonable distribution of hardness value, larger cover welding of the weld at 6 o 'clock position, repair welding phenomenon exists at the bottom welding position, and the crack originates from the groove of the bottom welding is non-fusion defect, which is not cleared in time during repair welding, and eventually expands to the filler welding metal, forming a crack.