南黄海铁板砂海床插桩问题分析与对策——常州35-2-1井插桩及作业过程分析

南黄海盆地勿南沙隆起西北部海区的海床表层土质为中密实的粉砂质细砂和砂质粉砂 ,俗称铁板砂。自升式钻井平台在这种土层中就位插桩时 ,桩腿插入困难 ,插桩深度很浅 ,但在钻井作业过程中平台桩腿又时常发生下沉现象 ,严重影响钻井作业 ,甚至危及平台安全。通过分析平台桩腿下沉原因 ,结合常州 35 - 2 - 1井作业的实践 (该井在作业中桩腿曾下沉 2 8次 ) ,提出对策和建议 ,为今后类似的钻井作业提供借鉴

Analyses and Strategies of Piling into Ferro-Plate Sand Seabed in South Yellow Sea

The surface soil property on the seabed northwest area of Wunansha uplift in the South Yellow Sea Basin is medium compact silt fine sand and sandy silt, which are usually called ferro plate sand. It was difficult to pile into such seabed for a jack up platform which piling depth was very shallow. During drilling operation, the platform legs often sunk, that it affected the operation, even safety on the platforms. Analyzing the reasons of platform legs through the operational practice of Changzhou 35-2-1 well, the paper brings forwards strategies and suggestions for the problems. And it provides the reference for the drilling operation in the future.