摘要
钻井过程中钻柱振动的位移信号较难获取且相关研究较少。为进一步认识钻井过程中井下发生涡动时钻柱的振动特性,利用近钻头测量工具采集某深井旋转钻进过程中的振动加速度,结合误差控制算法在频域上对振动加速度信号进行二次积分,得到振动的位移信号;通过分析钻柱涡动时的振动位移特征,并结合钻柱自转、公转的耦合作用和钻柱相对于井筒的位置,以实测到的“半频涡动”现象为例,解释了钻柱正向涡动和反向涡动时的振动规律。研究分析发现:对于测得的井下加速度信号,在频域积分过程中引入误差控制方程,通过设置预期目标精度可有效抑制低频分段的积分误差。当发生涡动时,切向和法向振动加速度曲线的振幅为正常钻进时的4倍以上,振动位移曲线的振幅为正常钻进时的10倍左右并呈现明显的周期性波动。波动周期受钻柱自转和公转耦合作用的影响,通常反向涡动时切向位移曲线的波动周期小于正向涡动,反向涡动比正向涡动更加剧烈。但在钻进过程中,受钻头与地层切削作用和钻柱与井壁之间相互摩擦的影响,也会出现正涡与反涡交替出现的情况,并不能仅通过振动位移信号的周期来判断正向涡动和反向涡动。研究结果对描述涡动时的振动特征,判断涡动的发生和及时采取措施消除涡动,缓解钻具疲劳具有指导作用。
The displacement signal of drill string vibration is difficult to be obtained in the actual drilling process.To further understand the vibration characteristics of drill string when whirling motion occurs in wellbore during drilling process,first,the near-bit checking tool was used to acquire the vibration acceleration during rotary drilling of a deep well,and then the error control algorithm was used to conduct secondary integration for the vibration acceleration signal in the frequency domain,so as to obtain the displacement signal of vibration.Finally,by means of analyzing the vibration displacement characteristics of drill string at the time of whirling motion,combined with the rotation and revolution coupling effect of drill string and the position of the drill string relative to the wellbore,the measured“half frequency whirling motion”phenomenon was taken for example to explain the vibration laws of the drill string during forward and backward whirling.The research results show that for the measured downhole acceleration signal,the integration error of low-frequency segmentation can be effectively suppressed by introducing an error control equation in the frequency domain integration process and setting an expected target accuracy.When whirling motion occurs,the amplitude of tangential and normal vibration acceleration curves is more than 4 times that of normal drilling,and the amplitude of vibration displacement curve is about 10 times that of normal drilling,showing obvious periodic fluctuations.The fluctuation period is affected by the rotation and revolution coupling effect of drill string;the fluctuation period of tangential displacement curve of backward whirling is generally smaller than that of forward whirling,and the backward whirling is more severe than forward whirling.However,in the drilling process,affected by cutting of formation by bit and friction between drill string and wellface,forward whirling and backward whirling may occur alternately,and the forward whirling and backward whirling cannot be judged only by the period of vibration displacement signal.The research results have a guiding role in describing the vibration characteristics during whirling,judging the occurrence of whirling,and taking measures in time to eliminate the whirling and alleviate fatigue of drilling tools.
作者
张涛
杨振鹏
李军
王苗瑞
王梦凡
郭子娴
Zhang Tao;Yang Zhenpeng;Li Jun;Wang Miaorui;Wang Mengfan;Guo Zixian(Beijing Key Laboratory of High Dynamic Navigation Technology,Beijing Information Science&Technology University;Key Laboratory of Modern Measurement&Control Technology,Ministry of Education;China University of Petroleum(Beijing);Harbin Institute of Information Technology)
出处
《石油机械》
北大核心
2025年第7期22-31,共10页
China Petroleum Machinery
基金
国家自然科学基金重大科研仪器研制项目“钻井复杂工况井下实时智能识别系统研制”(52227804)
国家自然科学基金面上项目“底部钻具高频扭转振动响应机理及识别方法研究”(52274003)。
关键词
近钻头测量
频域积分
涡动
位移重建
振动特性
near-bit measurement
frequency domain integration
whirling motion
displacement reconstruction
vibration characteristics
