Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11261687 | Wellhead sealing device of sucker-rod pumping machine | Licheng Yu | 2022-03-01 |
| 10760367 | Wellhead sealing device of sucker-rod pumping machine | Licheng Yu | 2020-09-01 |
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11261687 | Wellhead sealing device of sucker-rod pumping machine | Licheng Yu | 2022-03-01 |
| 10760367 | Wellhead sealing device of sucker-rod pumping machine | Licheng Yu | 2020-09-01 |