Abstract:
Electric resistance welded steel pipe excellent in weld zone quality suitable for oil country tubular goods and line pipe wherein steel plate forming the base metal of the electric resistance welded steel pipe has a predetermined chemical composition, the contents of Ca, O, S, Ce, La, and Al satisfy XCASO = ( Ca O + Ca S + 0.285 Ce + La O + 0.285 Ce + La S ) × ( Al Ca ) > 78 the oxide-based inclusions in the weld zone of the electric resistance welded steel pipe contains one or both of Ce and La, and the long axis/short axis of the oxide-based inclusions is 2.5 or less.
Abstract translation:电焊焊接钢管焊接区质量优良,适用于油罐管和管线管,其中形成电阻焊钢管基体的钢板具有预定的化学成分,Ca,O,S,Ce, La和Al满足电阻焊钢的焊接区域中的氧化物系夹杂物的XCASO =(CaO + Ca S + 0.285 Ce Ce + La O + 0.285 Ce + La S)×(Al Ca)> 78 管含有Ce和La中的一种或两种,氧化物系夹杂物的长轴/短轴为2.5以下。