随钻声波测井隔声体性能评价实验研究  

Experimental Research on Performance Evaluation of LWD Acoustic Isolator

作　　者：苏远大 庄春喜 邓林 李玉霞 秦玉坤 

机构地区：[1]中国石油大学地球科学与技术学院,山东青岛266555 [2]中国石油集团测井有限公司,陕西西安710077

出　　处：《测井技术》2011年第5期402-405,共4页Well Logging Technology

基　　金：国家高技术研究发展计划(863计划)(2007AA06Z232);国家油气重大专项(2011ZX05020-002);中央高校基本科研业务费专项资金资助

摘　　要：隔声体是随钻声波测井的关键部件,既要保证有足够强度以满足钻井的需要,又要有效地衰减钻铤直达波的干扰,以便测到准确的地层信号。提出了一种用随钻声波测井单极子换能器测量隔声体声衰减性能的实验方法。采用发射和接收换能器均放在隔声体两端的补偿声衰减测量方案。通过推挽式功率放大器强迫驱动发射换能器产生不同主频的声波信号沿隔声体传播,测量并计算出不同频率的钻铤直达波经隔声体前、后的声幅曲线。给出了实际随钻声波测井隔声体短节的实验室测量实例,并确定出了该结构隔声体的钻铤直达波最佳隔声阻带及最大衰减系数。The design of LWD acoustic isolator is crucial to LWD tool development. The isolator should effectively attenuate the direct collar wave while maintaining sufficient strength to meet the drilling requirement. An experimental method is designated to measure the isolator＇s sound attenuation properties by using the realistic LWD monopole transducer. By placing transmitting and receiving transducers on opposite sides of the isolator, the method measures the compensato- ry attenuation of the sound wave through the isolator. The transmitting transducer is energized by a Push-Pull Power Amplifier at various frequencies in order to determine the isolator＇s performance as a function of frequency. The direct waves along drill collar before and after the isolator are recorded and the amplitude curves are calculated. This paper presents the laboratory measurement results for an LWD isolator joint. The measured sound attenuation property is characterized by the best sound insulation stop band and the maximum attenuation coefficient of the isolator.

关 键 词：随钻声波测井 声波隔声体 钻铤波 声衰减 衰减系数 实验 

分 类 号：P631.84[天文地球—地质矿产勘探]