摘要 |
<p>The profile has a set of narrow line or groove-shaped recesses (6) formed in a radial direction (R) with a radial inner extending region and a radial outer extending region. The recess is formed as a fine cut (7) with a cutting width (D) in the radial outer region and as a tubular opening channel (8) with maximum opening width (B) in the radial inner region, where the opening width is greater than or equal to two times of the cutting width. A set of parallel line-shaped radial projections (10) are formed at a deep bottom (9) that radially inwardly limits the opening channel.</p> |