| 摘要 |
<p>In an arrangement for the hydrodynamic strengthening of nonwoven materials, tissue, or paper, or for the needling of woven or knitted materials, a liquid processing medium is sprayed from a number of nozzles (7) against the material (2). The arrangement includes a permeable sheet metal drum (10) arranged opposite the nozzles and possibly subjected to a negative internal pressure, which acts as an intrinsically rigid support for the material during the needling process. The cylindrical surface of the drum is covered by a thin, liquid-permeable, sheet (12) with micro-fine holes, and between the drum surface (10) and the cover (12) is placed an inherently unstable under-covering made up of strips (13) which act solely to increase the distance between the drum surface (10) and the covering (12). The strips are arranged at a small and regular distance apart on the whole of the drum surface, the drum surface lying directly against their inner surfaces and the outer covering lying directly against their outer surface.</p> |
