Issued Patents 1997
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5658473 | Method for producing lengthwise welded metal tubes | — | 1997-08-19 |
| 5628447 | Method of manufacturing internally grooved tubes for heat exchangers | — | 1997-05-13 |
| 5613631 | Method for producing a lengthwise welded metal tube | Harry Staschewski, Klaus Porcher | 1997-03-25 |