Grooving Corrosion Behavior of J55 Steel-Grade Casing with Electrical Resistance Welded Seam

The corrosion behavior of the electric resistance weld (ERW) seam of J55 steel-grade casing was studied by constant potential anodic polarization accelerated corrosion electrochemical test. The surface morphology and three-dimensional microscopic characteristics of samples were observed by laser confocal microscopy and the corrosion sensitivity coefficient of groove corrosion was analyzed. The influence factors of the groove corrosion were analyzed and the economics of the seamless casing and ERW casing were compared. The results show that selective corrosion of J55 steel-grade ERW casing occurred, and there were pits in the weld area; the sensitivity coefficient of groove corrosion was less than 1.3, which was not sensitive to groove corrosion. Compared with J55 steel-grade seamless casing, the economy of J55 steel-grade casing with ERW seam was better.