Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8864105 | Ball valve seats and ball valves designed with equilateral triangle section methods | Changxiang Xu, Mao Xu | 2014-10-21 |
| 8439330 | Stem shoulder seal with double rings and an assembly of independent dual stem seals | Changxiang Xu, Mao YANG | 2013-05-14 |