Issued Patents 2020
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 10815743 | Depressuriz od for downhole annulus drilling fluid | Zhichuan Guan, Yucai Shi, Hualin Liao, Ben Guan | 2020-10-27 |
| 10801282 | Screw drill bypass valve with large displacement diversion function | Yucai Shi, Zhibin Fan, Zhichuan Guan, Weixing YANG, Zhixiang Teng +2 more | 2020-10-13 |
| 10718176 | Drilling speed improvement device capable of producing both hydraulic pulse and impact vibration | Hualin Liao, Jilei NIU, Zhichuan Guan, Yandong Yang, Yucai Shi +1 more | 2020-07-21 |