深水导管喷射安装过程中管柱力学分析

根据深水导管喷射安装作业特点，建立了该过程中的管柱静力学模型，并应用加权残值法进行了求解，得出了在考虑环境载荷、钻柱结构及钻井船偏移等因素影响下的管柱变形和应力分布规律。研究结果表明，中深层海流对管柱变形影响最大，合理设计钻柱结构和控制钻井船偏移是保证深水导管垂直安装和钻柱抗拉强度安全的关键。深水管柱的弯曲正应力在钻柱的上下两端作用明显，进行钻柱强度设计时，必须考虑管柱横向变形引起的弯曲正应力，提出了相适应的钻柱结构优化方案。作业初期，钻井船向海流负方向适当偏移，有利于控制导管的入泥倾角；遇阻活动管串时，钻井船向海流正方向适当偏移，能够有效地降低钻柱危险截面上的最大拉应力。

Tubular mechanics in jetting operation of conductor under deepwater condition

Based on the features of load and boundary conditions in jetting operation of conductor under deepwater condition, a tubular mechanic model was established, which was solved by weighted residual method to calculate the change regulation of tubular deformation and stress distribution associating with the environment load, tubular composition and drill ship offset. The middle-deep ocean currents have great effect on the deformation of pipe string. The design of drill string composition and control of drill ship offset are important for the successful operations of conductor in deep water. The bending normal stress of drill string is significant at both ends of tubular, so it should be considered in the tension strength design of drill string. A suitable drill string composition is suggested to be used in deep-water jetting operations. In the primary stage of operation, the offset of drill ship to the negative direction of sea current benefits to control the dip angle of conductor. The maximal axial stress in dangerous section of pipe string can decrease when the offset inclines to the positive direction of sea current while working the pipe under the resistant state.