Multifunctional Ultrasound Imaging Logging Tool Design for Casing Wells of Offshore Oilfield in China

The paper shows the development of the multifunctional ultrasound imaging logging tool design for casing wells of offshore oilfield in China. It presents a multifunctional ultrasound imaging logging tool. The instrument can be completed simultaneously casing wall imaging, measurement and an interface damaged casing cement evaluation. Compared with traditional instruments, the instrument has a higher position and vertical accuracy. Field test results show that the measurement accuracy of the instrument can be cased hole logging project to promote the use. Ultrasonic imaging technology has been widely used in recent years in the cased hole logging in engineering. The main issue is to deal with the early completion of the well casing tube cement bonding quality evaluation and the development in the late emergence of casing corrosion and deformation (there will be more serious perforation and dislocation phenomena). Developed in this article multifunctional ultrasound imaging logging tool (hereinafter referred to as MUIL) using ultrasonic pulse echo detection methods, in one acquisition completed cased hole wall, casing thickness and cement cemented wells to 360 evaluation pericyclic imaging. Compared to conventional cement bond logging tool SBT, CBL, etc., MUIL can give the maximum precision of 3 degrees azimuth cementation evaluation, and through articulated missing azimuth gyro get cement, real full borehole cementation evaluation. Casing damage detection, dobby caliper, ultrasonic thickness measurement phase shift, the magnetic leakage thickness measurement instruments such as measurement principle reasons can not be applied to large size casing. And the measurement results for the average effect caused by azimuth accuracy is low, it is easy to overlook when measuring tiny casing damage. The azimuth MUIL high accuracy and vertical resolution in the measurement of casing damage, to have subtle good application.