BWG's Successful Application of Self-Developed Rotary Closed-Loop System (RCLS) - Case Study

In 2021, our self-developed Rotary Closed-Loop System (RCLS) was successfully deployed in the Niu 24-3111 oil well. The total running time of the tool was 96.5 hours, with 70.5 hours of active working time. The entire well operation proceeded smoothly without any incidents.

Well Background:
Niu 24-3111 is a natural gas directional well located in the Ciyutuo Niu 18 block of the Liaohe Oilfield. The RCLS tool enables the bottom-hole assembly to drill in a specified direction while maintaining full rotation—similar to how a car's steering wheel precisely controls direction. This allows field engineers to accurately manage the borehole trajectory, ensuring smoother well paths, better hole-wall quality, reduced risk of pipe sticking, and significantly shortened well construction time.

Application Details:
According to the well design, from 2,673 meters (where the inclination angle decreased from 15.53° to 4.97°) to 2,507 meters (where the azimuth increased from 195.15° to 233.81°), the RCLS was deployed for rotary steering. This section posed challenges due to severe conventional directional drilling pressure, poor steering efficiency, and adjacent wells requiring composite drilling to adjust azimuth.

During rotary steering operations:

● A 33% steering force was applied, achieving an inclination change rate of 3°/30m, enabling high-precision trajectory control.

● The total footage drilled with a single string of rotary steering tools reached 456 meters, with a cumulative working time of 70.5 hours.

● Surface downlink communication, drilling measurements, and downhole steering control all performed ideally, hitting Target 1 with a horizontal displacement of only 1.33 meters from the target center.

Conclusion:
The field application of the self-developed Rotary Closed-Loop System has effectively validated the functionality, reliability, and accuracy of the rotary steering tool.