Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 10196863 | Connection structure between pipe body and steel joint of aluminum alloy drill pipe | Yonggang Liu, Xiaojun Li, Chun FENG | 2019-02-05 |
| 10184596 | Connection structure between pipe body and joint of aluminum alloy drill pipe | Yonggang Liu, Qi Shi, Chun FENG | 2019-01-22 |
| 10036213 | Connection structure between pipe body and joint of aluminum alloy drill pipe | Yonggang Liu, Xiaojun Li | 2018-07-31 |