TY - JOUR ID - 22432 TI - Mechanical safety analysis of the gas lift completion string used for a high-pressure sandwich layer JO - Scientia Iranica JA - SCI LA - en SN - 1026-3098 AU - Luo, W. AU - Wen, J. AU - Qi, W. AU - Yang, Ming AD - Petroleum Engineering Institute of Yangtze University, Wuhan, Hubei 430100, China AD - Logging Technology and Engineering Research Institute of Yangtze University, Jingzhou, Hubei 434000, China AD - Research and Development Center, Tuha Oilfield Company, CNPC, Shanshan, Xinjiang, 838202, China AD - - Research Institute of Exploration and Development, Tuha Oil eld Company, PetroChina, Hami, Xinjiang 839009, China. - CNPC AMERICA LTD., Venezuela Y1 - 2022 PY - 2022 VL - 29 IS - 1 SP - 1 EP - 12 KW - high salt KW - high-pressure sandwich KW - dual tube completion KW - System reliability KW - the squeeze strength DO - 10.24200/sci.2021.50161.1543 N2 - This study examines the mechanical safety of a gas lift completion string in a certain oilfield, Algeria 438B block, having complex geological characteristics (a high salt and high-pressure sandwich). When an annulus is not supported within fluid column after unloading using conventional single-tube gas lift completion with positive lift oil production, inner pressure is so low that the pressure differential between the annulus and external casing is very large, which may damage the casing. Hence, a dual tube completion annulus filled with fluid that can resist pressure was used to overcome this problem, in the adjacent blocks using a gas lift production string with positive and reverse lift oil. However, this technology is complex and characterized by poor system reliability, large construction costs and maintenance difficulty. Considering the three aspects of a casing string, the squeeze strength, tensile strength and internal pressure strength, a gas lift completion string with dual concentric tubes and positive lift was preferably selected under conditions that have been verified as safe for production and a shut-in state. It was shown that this gas lift completion string design is feasible. UR - https://scientiairanica.sharif.edu/article_22432.html L1 - https://scientiairanica.sharif.edu/article_22432_f7608603691a4a45bdd812aaa9a54b0b.pdf ER -