瞬变电磁法套损检测探头偏心校正方法

摘要

With the massive increase in deviated well and horizontal well,the problem of tool eccentricity caused by factors of installation deviation of centralizer and gravity becomes more and more serious. In order to reduce influence of tool eccentricity on response signal,probe centering model based on transient electromagnetic(TEM) method is established. Combining angle and distance of logging tool to borehole axis,tool eccentricity correction method is proposed. The receiving signals with tool centering and tool eccentricity are analyzed. Experimental results demonstrate that the receiving signal model of tool eccentricity described in the paper can effectively reduce the influence of the eccentricity on casing inspection. The interpretation precision of logging data can be improved and the downhole media information can be better reflected.%随着斜井、水平井的大规模增加,扶正器的安装偏差、重力等因素引起的仪器偏心问题越来越严重.为了减小仪器探头偏心对测井响应信号的影响,建立了基于瞬变电磁(TEM)法的仪器探头居中模型,结合测井仪器偏离井眼轴线的角度和距离,提出了偏心校正方法,分析了仪器居中和偏心2种情况下的接收响应信号.试验结果表明:采用本文所述探头偏心情况下的接收信号模型,可有效减小仪器偏心效应对套管损伤检测的影响,提高了测井数据的解释精度,更准确地反映出井下介质信息.