Issued Patents 2021
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11143068 | Oil and gas separation device for internal combustion engine | Bin Yuan | 2021-10-12 |
| 11021919 | Mud circulation system for reducing the swab pressure while tripping out | Feifei Zhang, Yidi Wang, YueZhi Wang, Siyang Li | 2021-06-01 |