Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4840195 | Piston-backed gas pressure regulator | — | 1989-06-20 |
| 4813988 | Suitable distillation column packing for the cryogenic separation of air | Douglas L. Bennett, Keith A. Ludwig, Andrew J. Patrylak | 1989-03-21 |