The D-Tech rotary steerable tool is based on the ‘push the bit’ principle of steering. Available in three sizes, six hydraulically operated pistons are deployed against the wellbore to push the drill bit in the required direction. The pistons use the fluid within the drill string as a source of hydraulic power.
An electronic control unit which contains a six-axis sensor package is used to provide accurate tool-face control for all types of well profile. The tool is able to kick-off in the required direction in a magnetic steering mode and with an inclination over 5 degrees the tool can be steered in a gravity tool-face mode or a closed loop inclination hold mode.
When drilling laterals, an automatic closed loop mode is used to control the inclination to within +-0.1 degrees of the target. Similarly when in vertical hold, the inclination can typically be held to less than 0.5 degrees.
Once in the hole, the tool is programed by the directional driller by a down-linking process which involves variation of the mud pumps over a timed sequence. The down-linking process is simple and intuitive with a confirmation that the correct down-link sequence was sent being displayed on the directional drillers or MWD hand’s laptop.
Rigorous testing procedures and continuous investment in R&D ensures the D-Tech solution provides all of the functionality necessary for operators today and tomorrow, adding real value through reliable and enhanced drill bit performance.