钢悬链立管柔性接头用ASTM A707 L5钢性能检测与分析

Performance Test and Analysis of ASTM A707 L5 Steel for Flexible Joint of Steel Catenary Riser

柔性接头作为深水钢悬链立管(SCR)的关键部件,在海洋服役环境中承受着巨大载荷及面临着介质酸化导致的断裂风险等问题。因此,本研究针对钢悬链立管用ASTM A707 L5材料开展力学性能、氢致开裂(HIC)、应力腐蚀开裂(SSC)及裂纹顶端张开位移(CTOD)试验研究。试验结果表明,采用ASTM A707 L5钢制成的柔性接头其力学性、HIC、SSC及CTOD试验性能均能满足规格书要求;经HIC试验后试样的裂纹长度率(CLR)、裂纹厚度率(CTR)及裂纹敏感率(CSR)均为0;SSC试验后试样均为发生断裂,在10倍显微镜下观察,所有试样表面均未发现裂纹;CTOD的最小值为1.0792,平均值为1.1534.

As a key component of deep water flexible Joint of steel catenary riser(SCR),flexible joints are subjected to huge loads in the marine service environment and face the fracture risk caused by medium acidification.Therefore,the mechanical properties,hydrogen induced cracking(HIC),stress corrosion cracking(SSC)and crack tip opening displacement(CTOD)of ASTM A707L 5 for flexible Joint of steel catenary riser were studied.The test results show that the mechanical properties,HIC,SSC and CTOD test properties of the flexible joint made of ASTM A707 L5 Steel can meet the requirements of the specification;The crack length ratio(CLR),crack thickness ratio(CTR)and crack sensitivity(CSR)of the specimens were all 0 after HIC test.After SSC test,all the samples were broken,and no cracks were found on the surface of all samples under 10 times microscope,the minimum value of CTOD was 1.0792,and the average value was 1.1534.SSC Test is an effective method for the determination of CTOD.