HDD Tracking: Techniques for Accurate Borehole Navigation
Accurate tracking and locating are essential for successful Horizontal Directional Drilling (HDD). The contractor uses Measurement While Drilling (MWD) to monitor the borehole's trajectory, including inclination and magnetic direction. Common tools include the magnetic walkover system, which is preferred for its cost-effectiveness and ease of use, and the gyro tool, which is used in situations with magnetic interference. Accurate steering during the pilot hole phase ensures the drill bit follows the design path to the correct exit point.