应用事故树法对深水井控进行风险评估

he harm of deepwater blowout is much serious, which may lead to useless wellbore and disaster of rig and staff at very serious moment. At present, well blowout precaution and control technology in deepwater drilling is still world_class technical problem for domestic and overseas petroleum industry. This paper uses risk tree to decompose the top events which aroused accident in deepwater drilling, and has an emphasis on discussing the relationship of bottom events and their influence on system. It looks for the hole of system and analyzes the probability of top event taking corresponding corrective measures, which can provide academic foundation for reducing the happening of deepwater well control accident in maximum extent. Based on the analysis on risks in well control in deepwater drilling, the risk tree of well control in deepwater is established. And qualitative and quantitative analyses are made with the risk tree method. The risk analyses indicate that he critical factors of deepwater well control are the influences of equipment failures, design schemes and operating failures overrun the safe limits at shut in and kill processes. Dropping the chance of elementary events is helpful to preventing blowout. The chance of blowout enhanced 10 times with the elementary events enhanced 1 times. Aimed at the risk elements, measures of preventing blowout are put forward based on related technologies, equipments and operating personnel.