Directional Drilling Services

Directional Drilling Services employ proven rotary steering systems and mud motors for complex well profiles. Key technologies include the independently developed Welleader® rotary steering drilling system. The service supports various applications such as extended reach drilling and 3D multi-target wells. It integrates LWD/MWD tools for real-time data acquisition and gyro tools for accurate orientation. Experienced teams handle engineering design and on-site execution to optimize well trajectories and minimize non-productive time.

Welleader® Rotary Steering Drilling System

The Welleader® rotary steering drilling system made by COSL could control the well trajectory automatically while drill stem rotates. The system could realize fast response to drill bit position through precise guiding force vector control, with the capacity of measuring the high-precision near-bit inclination and tool face, and could realize automatic closed-loop control of the well deviation, adapt to complicated formation condition and drilling condition and complete the drilling operations of directional well,  directional well with complex 3D trajectory, extended-reach well, etc., with powerful well track control capacity and better wellbore quality. This system could integrate with Drilog® LWD system of COSL to realize precise geo-steering drilling.

· Directional Drilling while Rotating

Our Welleader® Rotary Steering Drilling System could realize the precise steering control with continuous drill string rotation, deliver excellent wellbore quality along with low tortuosity and less torque and drag. So it could shorten well construction cycle, and reduce the construction costs of drilling effectively.

· Real-time Surface Control

The control instruction could be sent to Welleader® by program-controlled bypass device CDL. Welleader® receives the instruction through detecting the changes in flow rate and implements it. Sending control instruction could be done while drilling ahead, as this would not impact the whole drilling efficiency.

· Precision Closed-loop Control

The steering unit of Welleader® system controls the steering force of three steering ribs in a closed loop by the hydraulic system of the motor pump, and forms stable size and orientation of steering resultant force. The steering data and tool status could be uploaded in real time via MWD while directional drilling ahead, and the directional driller could send instruction downhole in real time so as to control the well trajectory as required.

· Near-bit Measurement

Welleader® near-bit measurement module is located within 1.3m (1.1m for 675 series tool) behind the drill bit, and could obtain the tools’ position as well as the near-bit well inclination in the first place and provide precise guidance data for steering control.

· Multiple control modes

Welleader® supports multiple control modes like steering mode, stabilizer mode, angle hold mode etc., and could also realize automatic angle-holding drilling ahead by setting required inclination.

· Turbine Generator Powered

Welleader® is powered by a downhole turbine generator, which provides stable power for the steering unit. The turbine of the generator could be selected according to the specific situation of flow rate.

· Powerful Trajectory Control Ability

The stability of our Welleader® in trajectory control has been proved in field drilling in different geological environment in Xinjiang, Northeast, North China, the Bohai Bay, etc., At present, our Welleader® RSS is available for two hole size, respectively in 8.5″hole and 12.25″hole, and the dogleg severity can be reached up to 6.5°/30m.

· Real-time Geosteering

Welleader® could be connected to Drilog® seamlessly, and the geological engineer could obtain LWD data at the first time so as to make real-time decision, optimize and adjust the well trajectory to realize precise landing and drilling in interbedded formations.