超声反射波频谱分析的模拟和实验研究  

Simulation and Experimental Study on Spectrum Analysis of Ultransonic Echoes.

作　　者：周锦清[1] 郑侠光[1] 雷芙蓉[1] 

机构地区：[1]江汉测井研究所

出　　处：《测井技术》1995年第2期97-104,共8页Well Logging Technology

摘　　要：周锦清．超声反射波频谱分析的模拟和实验研究．测井技术，１９９５，１９（２）：９７～１０４半波层原理和多层介质反射波理论是固井质量检测方法研究的依据。在超声固井质量检测中，套管井内的反射波受井下复合介质特性的影响很大。理论模拟研究的结果表明，采用满足套管谐振频率的超声反射波频谱分析技术，可以区别和提取第一界面（水泥与套管）、第二界面（水泥与地层）胶结状态的特征信息，从而达到检测水泥胶结质量的目标。根据在不同介质参数实体模型中开展的反射波实验研究，本文确立了两个界面的频谱特征区（即频域），可分别在频域内提取特征信号，判别两个界面的水泥胶结质量，检测套管厚度，但检测水泥厚度较为困难。文中探索了界面间隙的影响，结果表明：厚度小于０．１ｍｍ的微间隙，与胶结良好（界面无间隙）的判据一致。The detection and evaluation of cement bond quality are discussed on the basisof the theory of half-wave length and multilayer-media reflection wave.The echoesin cased hole are strongly affected by sonic characteristics of downhole media.Simulation study shows that ultrasonic echo spectrum.analysis can be used to separatethe characteristics of the cementing status of the first boundary(cement-casing)from that of the second boundary(cement-formation)and extract those informationso as to evaluate the cement bond quality.According to the experimental study onthe different media of the test pits,specific spectrums of the cement boundaries aredetermined. These data can be used to evaluate the cement quality,to detect casingthickness. But it is difficult to evaluate the thickness of cement with spectrum analysis.The effect of microfissure on the signal is also discussed. The result shows thatit has no effect on the cement evaluation if microfissure is less than 0.lmm.

关 键 词：固井质量 频谱分析 测井 采油井 模拟 

分 类 号：TE256.9[石油与天然气工程—油气井工程]