Issued Patents All Time
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4230157 | Pipe having an end portion, the inner wall of which is provided with a circumferential groove, in which a sealing means is mounted and a pipe joint consisting of this pipe and a spigot end of a second pipe inserted therein | Per Frederiksen, Ebbe Sorensen | 1980-10-28 |