Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4852391 | Pipeline vehicle | Ola Ruch, Trond V. Johansen, Horst Poerner, Georg R. U. Gebhard, Robert A. Weber +1 more | 1989-08-01 |
| 4852614 | Shut-off device which can be inserted into a pipeline | Trond V. Johansen, Ola Ruch, Robert A. Weber, Bernd Veenhoff, Horst Porner +3 more | 1989-08-01 |