摘要 |
<p>The procedure consists of passing the sheet material (N) between a perforated cylinder (2) and a roller (4) with spring-loaded perforating fingers (9). The cylinder's perforations are formed by a series of detachable inserts (8) with holes in their flat outer surfaces (S) having sharp edges (8g), while the roller's fingers are designed to rotate as their interact with the perforations, shearing the fibres of the sheet material.</p> |