Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 9644856 | System and method for monitoring and controlling an HVAC system | Donald Raymond Rosentreter, Dan Lee Keown | 2017-05-09 |
| 7166177 | Method for forming double containment pipeline sections | Ralph Friedrich, Joie L. Folkers | 2007-01-23 |
| 6026862 | Double containment pipe sections | Ralph Friedrich, Joie L. Folkers | 2000-02-22 |
| 5725920 | Fiber-reinforced resin pipe having improved impact resistance | Ralph Friedrich, Duane G. Hemphill, Joie L. Folkers, Gordon G. Robertson | 1998-03-10 |