Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 9297242 | Structure for gunpowder charge in multi-frac composite perforating device | Guoan Zhang, Jianlong Cheng | 2016-03-29 |
| 9027667 | Structure for gunpowder charge in combined fracturing perforation device | Guoan Zhang, Jianlong Cheng | 2015-05-12 |
| 8960289 | Combined fracturing and perforating method and device for oil and gas well | Guoan Zhang, Jianlong Cheng | 2015-02-24 |
| 8943944 | Structure for gunpowder charge in multi-frac composite perforating devices | Guoan Zhang, Jianlong Cheng | 2015-02-03 |