动力定位钻井平台因机动性强、适用水深范围广的特点,在恶劣天气频发、海况复杂的南海海域得到广泛应用。动力定位钻井平台主要靠动力定位系统和配置推进系统来保持位置的相对固定,当平台受到外力作用导致动力定位失效时,平台会出现漂移,隔水管和井口系统受横向力作用导致隔水管下部总成解脱,造成井筒完整性破坏，人员设备受到严重影响;分析动力定位钻井平台配置的应急解脱系统,模拟计算作业时水深、天气海况条件,给出平台偏移极限计算和动力定位系统分析建议。通过动力定位系统在中深水井作业的风险分析,完善预防应对措施,结合在南海东部海域的成功实践经验,认为动力定位系统在中深水海域具备可实施性。

Dynamic positioning drilling platforms are widely used in the South China Sea, where severe weather and complex sea conditions occur frequently, due to their strong maneuverability and broad applicability across a wide range of water depths. These platforms mainly relie on positioning systems and configured propulsion systems to maintain the relatively fixed position. When the platform is subjected to external forces that cause dynamic positioning to fail, the platform will drift. This drifting can exert lateral forces on the riser and weuhead system, causing the lower riser assembly to disconnect, which compromises wellbore intergrity and severely impacts personnel and equipment. This paper analyzes the emergency disconnect system configured for dynamic positioning platforms, simulate the water depth, weather and sea conditions during operation, provides recommendations for platform offset limit calculation and dynamic positioning system analysis, and based on the actual application of middle and deep water wells in the South China Sea, calculates the platform’s minimum operating safety radius. It also anallyzes the feasibicity of using dynamic positioning system for operations in midium-deep water wells, and propose associated risks and mitigation measures. A comprehensive risk analysis has been performed on the application of dynamic positioning systems in mediumdeep water well operations,with a focus on refining preventive and management measures.Leveraging the successful experimental results from the eastern waters of the South China Sea,it is considered that the dynamic positioning system can be effectively implemented in medium-deep marine environments.