利用钻柱振动频谱判别钻柱复杂情况的方法

Determining method for downhole drill string movement station by using drill string vibration frequency spectrum

为实现钻井过程中井下钻柱运动状态以及井下复杂情况的实时监测,依据振动测试原理,结合实际钻井工况中钻柱振动特征,研制钻柱振动信号测量及处理系统。现场试验结果表明:钻柱出现黏卡、跳钻等现象后,利用快速傅里叶变换和小波变换处理方法可有效提取和识别钻柱在井下的振动特征;研制的钻柱振动采集系统可以应用于现场钻柱振动信号的采集、处理,其结果可以判断钻柱的井下工作状态。

For real time monitoring of drill string movement during drilling and downhole problems, based on vibrating measurement mechanism and actual drill string vibration characteristics, a new system of measurement and process of drill string vibration signal was developed. The analysis results for field data show that when stuck pipe or bit bouncing occurs the vibration characteristics of drill string can be effectively extracted and identified by the methods of Fourier transform and wavelet transform. The system can be used to gather and process drill string vibration signals, and the result of signals process can help to determine downhole working condition of drill string.