深海管线用X70厚壁管线钢的组织及性能分析  

Analysis on Microstructure and Properties of X70 Pipeline Steel with Heavy Wall Thickness Used for Deep-sea Pipeline

作　　者：牛爱军[1,2] 罗卓辉[3] 毕宗岳[1,2] 牛辉[1,2] 黄晓辉[1,2] 刘海璋[1,2] 

机构地区：[1]国家石油天然气管材工程技术研究中心,陕西宝鸡721008 [2]宝鸡石油钢管有限责任公司钢管研究院,陕西宝鸡721008 [3]中国石油天然气集团公司,北京100007

出　　处：《焊管》2014年第10期5-10,共6页Welded Pipe and Tube

基　　金：国家高技术研究发展计划(863计划)课题:深海高压油气输运高强厚壁管材关键技术研究(2013AA09A219)

摘　　要：通过对深海管线服役工况的分析，总结了深海用管线钢的技术特点，表明高强度、大壁厚、小径厚比管线钢管是深海用管线钢管的发展趋向。通过采用低C高Mn， Nb和Ti微合金化的成分设计和TMCP工艺控制，开发出了深水用X70钢级、厚壁36.5 mm管线钢，其全壁厚组织以均匀细小的针状铁素体＋少量M/A岛为主。对钢板进行了实物力学性能测试，测试结果显示：屈服强度480～550 MPa，屈强比≤0.82，-20℃下冲击功410 J以上，横向和纵向DWTT断口纤维率为100%，该深海管线用X70厚壁管线钢达到高强度、低屈强比、高韧性和优良低温抗动态撕裂能力的良好匹配。Through analysis of deep-sea pipeline service conditions,it summarized the technical characteristics of deep-sea pipeline steel,and showed that high strength, heavy wall thickness and small diameter-thickness ratio are the development trend for deep-sea pipeline steel pipe. By using high Mn,low C and Nb,Ti micro-alloying composition design,and TMCP process,the X70 pipeline steel with 36.5 mm thickness used in deep-sea pipeline was developed. The main microstructure of full thickness consists of uniform fine acicular ferrite and a small number of M/A island. The yield strength of steel plate arrives 480~550 MPa,the yield ratio≤0.82,the impact energy over 410 J at -20 ℃,the fiber fracture rate is 100% of horizontal and vertical DWTT, which achieves good matching with high strength,low yield ratio,high toughness and excellent dynamic tear resistance at low temperature.

关 键 词：深海管线用钢 X70钢 大壁厚 热机械控制工艺(TMCP) 微观组织 力学性能 

分 类 号：TG113[金属学及工艺—物理冶金]