钻井隔水导管自振特性及对海上钻井作业安全的影响研究

Natural Vibration Characteristics of Conduct Pipe and Its Influence on Offshore Drilling Operation Safety

本文针对自升式钻井平台隔水导管在钻井作业中的工作状态,采用结构力学多自由度系统的自由振动研究方法,建立了隔水导管与防喷器系统的集中质量悬臂杆体系。本文通过求解主振型的位移方程和频率方程,得到了隔水导管系统的自振频率。根据常用钻井条件下的钻井隔水导管和防喷器的工程参数,结合自升式钻井平台工作实际情况,计算结果考虑不同水深条件下自振频率和作业海域的波浪周期,对于在不同海域,提出了在可能发生谐振的海域和水深情况下,作业者从隔水导管串与防喷器设计到钻井作业过程中,应该注意采取的工程措施,为制订合理的设计和工程参数,避免隔水导管发生损坏,保障钻井作业安全,提供了科学的决策依据。

In this paper,aimed at the working state of the riser in the drilling operation of the jack-up drilling platform,the free vibration research method of the multi-degree of freedom system in structural mechanics is used to establish the concentrated mass cantilever rod system of the riser and the BOP system,and the natural vibration frequency of the riser system is obtained by solving the displacement equation and frequency equation of the main vibration mode.Based on the engineering parameters of the drilling riserand the blowout preventerundercommon drilling conditions,and in combination with the actual working conditions of the jack-up drilling platform,the calculation results take into consideration the natural vibration frequency and wave period of operation sea area under different water depth conditions.For different sea areas,it is proposed that in the sea area and water depth where resonance may occur,the operator should pay attention to the design of the riser string and the blowout preventer.In the process of drilling operation,the operator should pay attention to the engineering measures.This paper can provide scientific decision-making basis for formulating reasonable design and engineering parameters,avoiding the damage to the riser,and ensuring the safety of drilling operation.