Risk Assessment of Deep-Water Horizontal X-Tree Installation

Due to the high potential risk and many influencing factors of subsea horizontal X-tree installation, to guarantee the successful completion of sea trials of domestic subsea horizontal X-trees, this paper established a modular risk evaluation model based on a fuzzy fault tree. First, through the analysis of the main process oftree down and combining the Offshore & Onshore Reliability Data(OREDA) failure statistics and the operation procedure and the data provided by the job, the fault tree model of risk analysis of the tree down installation was established. Then, by introducing the natural language of expert comprehensive evaluation and combining fuzzy principles, quantitative analysis was carried out, and the fuzzy number was used to calculate the failure probability of a basic event and the occurrence probability of a top event. Finally, through a sensitivity analysis of basic events, the basic events of top events significantly affected were determined, and risk control and prevention measures for the corresponding high-risk factors were proposed for subsea horizontal X-tree down installation.