Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7431347 | Hollow sucker rod connection with second torque shoulder | Hugo Ernst | 2008-10-07 |
| 6991267 | Assembly of hollow torque transmitting sucker rods and sealing nipple with improved seal and fluid flow | Hugo Ernst, Daniel E. Johnson | 2006-01-31 |
| 6764108 | Assembly of hollow torque transmitting sucker rods | Hugo Ernst, Daniel E. Johnson | 2004-07-20 |