While rotary-steerable systems (RSSs) dominate the offshore directional-drilling markets, the land-based markets are still dominated by conventional directional-drilling tools. This paper presents a new RSS that is being designed and tested specifically for the onshore markets. The new tool is a short RSS that is designed to deliver a buildup rate of 15°/100 ft. It achieves this by the movement of two eccentric shafts relative to one another within the tool.
For directional drilling to be successful, it is important that the drillers have information on the orientation of the tool while they are drilling so they can best align the wellbore orientation to the reservoir target. Commonly, this is achieved with a measurement-while-drilling (MWD) tool that is typically 50 ft or more behind the drill bit. In some cases, these measurements are supplemented with some form of near-bit inclination reading. A further improvement would be to have both inclination and azimuth measured close to the bit and integrated into the drilling tool’s directional response, thereby enabling precise well placement without the need to project and correct continually from the MWD tool that lags considerably behind the drilling tool. This is the method adopted by the RSS described in this paper....
Designing and Testing of New Rotary-Steerable System for Use Onshore
01 December 2015