Instruments for Well Navigation and Drilling Optimization Evaluation

This chapter provides an introduction to drilling directional and horizontal wells and the two most common methods, sliding/rotating drilling with a bent-house hydraulic motor and rotary steerable systems (RSSs), utilized to accurately navigate a well to a target reservoir. At the heart of well navigation is a system known as measurement-while-drilling (MWD), which consists of magnetometers and accelerometers to measure the azimuth and inclination, respectively. A discussion on drilling dynamics sensors such as vibration, shock, downhole weight-on-bit (WOB), torque-on-bit (TOB) and drill bit revolutions per minute (RPM) to optimize drill bit penetration through rock formations is provided towards the end of the chapter.