摘要
在钻井过程中,钻头与井底岩面之间的冲击、钻柱与井壁之间的碰撞常引起强烈的振动。钻柱振动与钻压、转速、地层岩性、井身结构、钻头磨损状况等有关。它能引起钻柱的疲劳破坏,严重时可造成钻具断落及其它井下事故,甚至导致整个井眼报废。傅立叶方法分析钻柱振动谱,解释效果不理想,而小波分析能对各种时变信号进行有效的分解,能在不同频段上更细致地研究钻柱振动信号特征。在快速傅立叶变换方法的基础上,利用小波理论开发出了小波细化分析方法和小波包方法。经过室内实验和现场测试检验,小波分析能更清楚地反映数据的特征,得到的谱图更清晰,不仅为钻井工程监测和故障诊断提供依据,而且有助于建立钻井工况故障档案。
The interpretational effect is still imperfect,using Fourier method to analyze drill string vibration spectrum,but wavelet analysis can effectively separate all kinds of time variable signs,and drill string vibration sign characteristics can also be accurately studied in the different frequency spectrum.Therefore,based on fast Fourier transform method,this paper developed wavelet spectrum zoom analysis method and wavelet packet analysis method by using wavelet theory.Wavelet analysis could clearly reflect characteristic of data,in the meantime,frequency spectrum figure gained was clearer than Fourier,which did not only provide reference for drilling condition monitoring and fault diagnosis,but also was useful to establish fault file of drilling condition.
出处
《钻采工艺》
CAS
北大核心
2008年第2期7-9,9,共3页
Drilling & Production Technology
基金
国家自然科学基金资助项目(编号:90210022)
关键词
钻井
小波理论
钻柱振动
谱分析
drilling,wavelet theory,drill string vibration,spectrum analysis,application
