| 摘要 |
A method and a system for preparing a cellular web (20), useful for ground erosion protection, out of a sheet of yieldable material (10). The system comprises a set of rotary knives (30) and a complementary set of discs (32). Each pair of knives and discs is matched to form a cut in the sheet (10) when passed therebetween. Each of the rotary knives (30) comprises a cut-out (30a), the cut-outs (30a) of one knife being angularly shifted with respect to the cut-outs of two adjacent knives, so that a pattern of alternating incisions (12) and non-cut portions (14) along parallel lines are received in a staggered order, whereby the non-cut portions (14) of every second line are aligned with respect to each other, and non-aligned with respect to the incisions (12) of adjacent lines. |
