Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4834650 | Sealed rotary hearth furnace with central bearing support | Beverly E. Johnson, Joseph S. Beri | 1989-05-30 |
| 4818222 | Sealed rotary hearth furnace | Beverly E. Johnson | 1989-04-04 |