Study On Key Technology In Through-casing Resistivity Logging Calibration Facility

The cased hole formation resistivity logging technique is mainly applied to calculate the leaked current of the target layers by measuring the weak voltage drop on the casing between the three electrodes, thus obtain the strata of apparent resistivity, it can be used to confirming the saturation of remaining oil, identifying dead oil and gas formation, evaluating flooded oil layers, monitoring the saturation of fluids, etc. and by scaling the casing resistivity logging, guarantee the accuracy and scientific of measured data.This paper introduces in detail the overall scheme of the casing resistivity logging calibration facility and the measurements principle of the three electrode method of the casing fort-nation resistivity, and analyzes the metal casing transmission line model and the influencing factors in actual logging; moreover, the paper also design the signal regulate circuit and the signal acquisition circuit of the casing resistivity logging calibration facility, and prove the circuit performance through the measured data.The casing resistivity logging calibration facility is studied in depth, and through the precise resistance array completed the leakage current scale, and the calibration pool completed resistivity scale, finally, based on the theoretical analysis and experimental, regression equation of calibration device is given, and verify the scale device reality scheme is feasible.