The Development of an Integrated Logging Instrument Platform while Drilling

The goals were to detect characteristics of of multi-depth formations and evaluate mud intrusion as well as identify the formation lithology. To that end, researchers developed an integrated logging instrument platform while drilling capable of multi-parameter measurement such as resistivity and Gamma. According to the measurement methods like phase shift resistivity, attenuation resistivity, total Gamma and imaging Gamma, an eight-coil design (six senders and two receivers) was adopted, and the sensors such as Gamma probes, accelerometers, and fluxgates were attached. Meanwhile, the modular circuit design scheme consisting of transmitting circuit, receiving circuit and control circuit was applied. Researchers then defined the bus communication protocol to establish the information transmission among various functional modules. The firmware program for the logging instrument platform has been developed, which can not only measures the phase shift resistivity and attenuation resistivity data, but also measure the Gamma data and formation azimuth information. The test software for the platform has been developed to calibrate the instrument and enable the startup setting prior to running in hole, realize the issuing of control commands and upload the measurement data, and monitor and graphically process data such as resistivity, Gamma, inclination angle, and tool face. This integrated logging instrument platform could provide abundant high-quality logging data for high-angle well and horizontal well drilling, and acquire necessary data for formation evaluation, so as to provide technical support and best practices for the development of unconventional oil and gas reservoirs.