The Study Of Rapid Tie-in Technology Based On Pipeline Internal Plugin Deepwater

With the decrease of petroleum resources on land and in offshore area,submarine oil pipeline is extending to the deepwater.If leak accidents once occur in the deepwater,it might be more difficult to repair urgently,and will cause serious pollution to the environment.Therefore,it is of no delay and significant to design a full functional equipment which can plug the leaking pipeline or keep the oil from further polluting the environment rapidly.The study is conducted in order to realize temporary or long-term tie-in rapidly when the damaged pipeline is repaired,and maximize the pipeline shutting down time and leak time.Carrying on this research has significant meanings for breaking the overseas technical monopoly and improving the technology of deepwater work in our country.Based on research at home and abroad,framework and technological evolution of the rapid tie-in system are analyzed with the method of design methodology,it is found that The system is divided into pipeline internal plug,install device for the plug,rapid tie-in and transfer subsystems,and schema and structural design of the various subsystems are described in this paper.The hydrodynamic analysis of the transfer subsystem is conducted and the result shows that the transfer scheme is feasible.The theoretical analysis for the parametric resonances of the oil hose in the transfer subsystem is performed,and the frequency of sea waves which can lead to parametric resonances is found out.Particular attention is paid on the research of slips which are the core component of pipeline internal plug.Calculate methods of initial anchorage forces,embedded depth and stress distribution of the slips are found by mechanics analysis.The effect of slip tooth's rake and relief angles on the stress distribution in the tooth are analyzed,and the dimensions of the slips are optimized.Studies on slip tooth are carried out experimentally,the theoretical derivation and stimulation results are validated by experimental results.Study on the tooth profile by using comparison experiment is also detailed,and merits and demerits of linear and round tooth are found.