Fred E. Watkins
13Patents
10h-index
9Co-inventors
61Inventor score
Filing activity: Sep 26, 1975 → Aug 27, 1992
Most-cited inventions
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US4077473A | Well safety valve | Fixed Constructions | 33 | Expired |
| US4160484A | Surface control well safety valve | Fixed Constructions | 31 | Expired |
| US3981358A | Well safety valve | Fixed Constructions | 28 | Expired |
| US3993129A | Fluid injection valve for wells | Emerging Cross-Sectional Technologies | 25 | Expired |
| US4161984A | Well locking device and method | Fixed Constructions | 24 | Expired |
| US4161960A | High and low tubing pressure actuated well safety valve | Emerging Cross-Sectional Technologies | 21 | Expired |
| US4159643A | Method of and apparatus for measuring bottom hole well pressure | Fixed Constructions | 18 | Expired |
| US4360064A | Circulating valve for wells | Fixed Constructions | 17 | Expired |
| US5257665A | Method and system for recovering liquids and gas through a well | Fixed Constructions | 15 | Expired |
| US4254829A | Well locking device | Fixed Constructions | 14 | Expired |
| US4106563A | Sidepocket mandrel | Fixed Constructions | 9 | Expired |
| US4476924A | Grease injection control head having a specific gas trap | Fixed Constructions | 5 | Expired |
| US4415028A | Apparatus for measuring bottom hole well conditions | Fixed Constructions | 2 | Expired |
Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.