Optimum Design Of Open Hole Test String For Offshore High Temperature And High Pressure Wells

With the development of offshore oil and gas exploration and development,the development of high temperature and high pressure oil and gas reservoirs will gradually increase in the future.Due to the shortage of complex open hole test technologies in high temperature and high pressure wells,it is particularly important to optimize the test string suitable for open hole test in high temperature and high pressure wells at sea.In this paper,based on the current situation of open hole test technology in the field of high temperature and high pressure,comprehensively considers the influence of complex downhole conditions such as high temperature,high pressure and toxic gas on the test string,analyzes and summarizes two types of open hole test string suitable for offshore high temperature and high pressure wells: one-pass string and insert string.Establish axial force calculation model of open hole test string in high temperature and high pressure wells,through the example analysis,calculate the main influencing factors of axial force under different working conditions,such as temperature effect,ballooning effect,the piston effect.Then optimizing test process,test tools and work parameters,determine the length of expansion joint used by one-pass string or the length of the inserted sealing pipe of the insert string,and the overall structure of the offshore test string in the open hole of the high temperature and high pressure wells in finally determined.