摘要
提出了一种利用钻柱轴向振动调幅信号实现岩性识别的方法。三牙轮钻头钻进不同岩石时易引发携带强烈背景躁声的钻柱轴向调幅振动信号 ,采用小波包多层分解、域值滤波、最优向量选取及重构信号等方法并结合快速傅立叶变换频谱分析 ,有效地提取出被噪声淹没的调幅信号 ,检测出中心频率及其边频率带 ,计算出与岩性相关的综合齿数 ,从而快速。
A new lithology identification method based on axial amplitude modulation signal of drill string is proposed. The background noise on drilling string is easy to be induced. The axial amplitude modulation signal can be produced while drilling in rock formation with different lithology by using three-cutter bit. The wavelet packet multilevel-decomposition method was applied to threshold filter. The best wavelet coefficient vector is analyzed by fast Fourier transform, and the modulated feature is extracted from the corrupted signal. The central frequency and sideband frequency are detected on spectrum figure. The number of complex tooth on bit corresponding to different lithology of rock has been obtained. The effective and fast lithology discrimination has been realized.
出处
《石油学报》
EI
CAS
CSCD
北大核心
2004年第3期91-94,共4页
Acta Petrolei Sinica
基金
国家自然科学基金资助项目"远程钻井网上会战智能应用系统理论与方法的研究"(No .50 0 740 2 4 )。
关键词
钻井
三牙轮钻头
轴向振动
调幅信号
小波包理论
岩性识别
drilling
three-cutter bit
axial vibration
amplitude modulation signal
wavelet packet theory
lithology identification
