探讨声幅刻度对水泥胶结测井质量的影响

Discussion on the Influence of Sound Amplitude Calibration on Cement Bond Logging Quality

水泥胶结测井实质上就是通过测量水泥环和套管、地层之间的声学参数来判识水泥胶结质量。水泥胶结测井质量的可靠性主要取决于其刻度的精确性,声幅刻度只有在若干苛刻条件下进行才能够保证其准确性,从刻度时间、刻度方向和刻度速度方面阐述声幅刻度和测井过程的一致性原则,从波峰探测方式和首波到达时间方面阐述声幅刻度中关键参数的选择,对于无自由套管的声幅刻度问题,从现场刻度、调用刻度、实验刻度方面给出参考。

Cement bond logging is essentially to determine cement bond quality by measuring acoustic parameters between cement sheath, casing and formation. The reliability of cement bond logging quality mainly depends on the accuracy of its calibration. Acoustic amplitude calibration can only be carried out under some harsh conditions to ensure its accuracy. The consistency principle of acoustic amplitude calibration and logging process is expounded in terms of calibration time, calibration direction and calibration speed. The selection of key parameters in sound amplitude calibration is expounded from the aspects of peak detection mode and arrival time of first wave. For the problem of sound amplitude calibration without free casing, reference is given from field calibration, call calibration and experimental calibration.