1. School of Mechatronic Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500, China 2. School of Mechanical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031, China 3. Sinopec Shengli Petroleum Engineering Co., Ltd. Southwest Branch, Deyang, Sichuan 618000, China 4. CCDC Drilling &Production Engineering Technology Research Institute, Guanghan, Sichuan 618300, China 5. Southwest Oil & Gas Field Company, CNPC, Chengdu, Sichuan 610051, China
In view of the deficiencies in the study of two-way shock absorber in marine oil and gas drilling and its abnormal failure, the failure mechanism is analyzed based on the structural principle of two-way shock absorber and field use. On the basis of the analysis, a series of feasible measures are established. The results show that the main causes leading to two-way shock absorber's failure include seal failure, thread failure, loosening between spindle and outer cylinder, and the design defects of nine-thread. Accordingly, avoiding artificial damage, preventing seal failure, strengthening supervision of all positions and improving the nine-thread structure are reasonable choices to avoid shock absorber failure. The conclusions are helpful to effectively reduce the risk of shock absorber failure and the failure probability, which are of great significance to improving production speed and drilling safety.