| 摘要 |
PURPOSE:To enable surface treatment low in energy cost without requiring a large quantity of clarified water, by differentiating the structure of fine orifices supporting the end parts of a metal web and that of fine orifices supporting the parts other than said end parts of said metal web. CONSTITUTION:The jet orifices 5-1 of back-up plates 5 supporting the end parts 11 of a metal web 1 are finely and densely arranged and the jet orifices 5-2 of said back-up plates 5 supporting the parts other than said end parts are made larger than said jet orfices 5-1 and arranged coarsely. A slurry is sprayed to the central part of the metal web 2 from nozzles 3 by high pressure water while the running metal web 1 is supported by a roll 2 to perform the surface roughening of said web 1 and, subsequently, the slurry is sprayed to both end parts of the metal web 1 by nozzles 4 while the metal web 1 is supported by the back-up plates 5 to perform the surface roughening of the end parts. As mentioned above, because only the end parts of the web 1 are supported by high pressure water from the fine jet orifices 5-1 in performing surface treatment in such a state that the web 1 is supported in a non-contact state by the back-up plates 5 and the other parts are supported by medium pressure jet water, the supply amount of clarified water and energy cost are reduced and the web can be run stably. |
