【作者】 王震；

【导师】 程方杰；

【作者基本信息】 天津大学 ， 材料加工工程， 2018， 硕士

【摘要】 随着陆地和近海油气资源的日益枯竭,钢悬链立管以其独特的优势在深水和超深水油气资源开发方面获得了各个国家的青睐。而我国在深水油气资源开采方面的研究起步较晚,目前迫切需要研发一种高质量的焊接工艺来保证钢悬链立管焊接接头良好的综合性能,尤其是疲劳性能。本文采用窄间隙TIG焊接方法对X65材质的钢管进行了全位置(5G)和横焊位置(2G)的环缝对接工艺开发。分析研究了打底焊、填充焊和盖面焊过程中影响焊缝成型的主要因素和注意事项,给出了合适的焊接工艺参数;探索了接头错边和装配间隙对打底焊工艺的影响规律,给出了错边和间隙的容许范围。对全位置和横焊位置环缝焊接接头的力学性能进行了测试和分析。结果表明,采用窄间隙TIG焊接的接头常规力学性能和断裂韧性均十分优良;三个典型应力范围下的疲劳性能测试数据均在DNV-RP-C203标准规定的钢悬链立管S-N疲劳设计曲线F3之上,疲劳性能优良;研究还发现,错边方式对横焊接头疲劳裂纹的其起裂位置有着重要影响,“上错边”接头的疲劳裂纹主要从根部焊趾上侧起裂,无错边接头的疲劳裂纹主要从根部焊趾下侧起裂,而“下错边”接头的疲劳裂纹则全部从根部焊趾下侧起裂。更多还原

【Abstract】 With the depletion of the land and offshore oil and gas resources,the steel catenary riser has been favored by various countries for its unique advantages in the development of deep-water and ultra-deep-water resources.The research on deep-water oil and gas exploitation was carried lately in China,so a high-quality welding technology was urged to develop to ensure the good comprehensive performance of the steel catenary riser joints,especially the fatigue performance.The main factors and matters needing attention were studied in the process of backing,filling,and capping welding to obtain the appropriate parameters.Then,the effect of misalignment and assembly gap on backing welding procedure,so as to provide the error range of misalignment and assembly gap.Then,the mechanical propertied of the full position and horizontal position welding joints were carried and analyzed.The results showed that the conventional mechanical propertied and fracture toughness of narrow gap TIG welding joints are excellent and the fatigue data is upon the F3 curve of the DNV-RP-C203 standards at the typical stress range.Besides,the misalignment mode has a significant influence on the fatigue cracking initiation position of horizontal welding joints.The fatigue crack of upper-misalignment-joint is almost from the upper side of the root toe,and the fatigue crack of joints without misalignment is mainly from the bottom of the root toe,and the fatigue crack of down-misalignment-joint is all from the bottom of the root toe.更多还原