Analysis of the causes of the outer surface folding defects in N80-Q oil country tubular goods  

作　　者：PAN Dagang CAI Haiyan TAN Zhunli YU Jie 

机构地区：[1]Tube ＆ Pipe Technology Center, Research Institute, Baoshan Iron ＆ Steel Co., Ltd., Shanghai 201900, China

出　　处：《Baosteel Technical Research》2011年第1期56-59,共4页宝钢技术研究（英文版）

摘　　要：The causes to the outer surface folding defects in N80-Q oil country tubular goods （OCTG） were investigated through the observation of the defects＇ morphology, microstructure and the analysis of the chemical compositions. It is believed that the defect was resulted from the intrinsic flaws that originally existed on the billet; they were extended and oxidized during the following reheating and rolling processes. With more strict quality control and inspection of the billet, the defect can be prevented effectively from occurring.The causes to the outer surface folding defects in N80-Q oil country tubular goods （OCTG） were investigated through the observation of the defects＇ morphology, microstructure and the analysis of the chemical compositions. It is believed that the defect was resulted from the intrinsic flaws that originally existed on the billet; they were extended and oxidized during the following reheating and rolling processes. With more strict quality control and inspection of the billet, the defect can be prevented effectively from occurring.

关 键 词：OCTG DEFECT ROLLING MICROSTRUCTURE heat treatment 

分 类 号：TG335.56[金属学及工艺—金属压力加工] TB553[理学—物理]