Design And Research Of Casing Hanger And Seal Assembly Running Tool

The subsea wellhead system is the foundation of offshore drilling, run to bore hole on sea floor by its running tools which are the core equipment of well construction. With China’s oil exploration and development to the abysmal sea, the study of key technology and the core equipment of marine deep-water drilling is much more important. The paper combines the National High Technology Research and Development program(863) on Marine Technology projects“the Key Technology and Equipment of Nanhai Deep-water Oil and Gas Exploration and Development”and the second batch of project topics“Research on Deep-water Subsea Wellhead System and the Production Platform Extraction Wellhead System(2007AA09A102)”,research is carried out the design and related technology of casing hanger and seal assembly running tool.Based on the comparative analysis of the related technology abroad, the schemes of running casing hanger and seal assembly down to bore hole is studied comprehensively for safety,high efficiency,high reliability and lower operation cost. A design scheme of Casing Hanger and Seal Assembly Running Tool is proposed for South China sea deep-water drilling. Based on its characteristics of function andstructure, integrated modular design strategy was proposed, and partioned the function structure element module of running tool.Studied the performance of Casing Hanger and Seal Assembly Running Tool influenced by marine environment load, it turned out that marine environment load increases the bendingmoment of running tool; studied the factors influencing impact of running tool and seal assembly by analysing impacting process and theoretical derivation.Comprehensively analyzed the runing process of casing hanger and seal assembly affected by depth of water, wind, wave, ocean current,etc.,and established the mechanical model of casing hanger and seal assembly running tool; studied the factors influencing impact of running tool and seal assembly by analysing impacting process and theoretical derivation.According to the function requirement of casing hanger and seal assembly running tool, finished the design of connection structure of seal assembly, connection structure of casing hanger, hermetically-sealed structure, flow-by structure, washing structure and the whole structure of running tool; and finished the finite element analysis of key components. By applying ANSYS/LS-DYNA, the collision impact of running tool and seal assembly was simulated and analyzed, which proved the collision impact theory analysis,and analyzed the key factors of collision impact(initial collision velocity and distance). By studying the structure performance of casing hanger flow-by, it turned out that the relation between flow-by diameter value and decompression and drainage effects, casing hanging structure strength, and confirmed the optimum value range of flow-by.