The at-bit sub can dramatically improve well production, especially in thin formations, by ensuring that the well bore is drilled in the optimum position of the formation. When using the at-bit sub, steering of the drill string is dramatically improved due to its close proximity to the drill bit and its ability to provide up/down gamma data without interrupting the drilling process. It’s not enough to just know whether or not you are in the formation. With the at-bit sub we can tell if the formation is better above or below the bit because gamma counts are correlated with magnetic roll on the fly. Because of that correlation, we can compare the formation above and below the bit and constantly correct direction to achieve a well bore that is better positioned within the formation.

The at-bit sub is designed to be used with our Electromagnetic (EM) MWD tool. The at-bit sub is installed between the drill bit and mud motor, and measures inclination, gamma, RPM and roll. The sub works together with our EM MWD to provide near real-time data that originates only inches behind the drill bit. During operation, the At-Bit sub sensors and transmitter are powered by lithium batteries. Data from the sub is gathered and wirelessly transmitted around the mud motor to the MWD, where it is processed, logged and combined with other MWD data and then ultimately relayed to the surface via an EM signal. Our surface computers gather that data from the MWD through surface mounted antennas, and process the data to client specifications.


  • Available in 5" and 6.5" sizes
  • Provides accurate inclination and rotation speeds at the bit, up to 300RPM
  • Azimuthal gamma ray provides clear "up" and "down" readings
  • Seamless, wireless link to our MWD systems


  • Geosteering in tight formations and long laterals
  • Collision avoidance situations