| 摘要 |
An apparatus for texturing the surface of wet cast plastic acoustical composition during manufacture of acoustical tiles by use of spinning air rolls. In the apparatus, at least one hollow cylindrical roll that is perforated in a random manner is suspended over the surface of wet cast plastic acoustical composition, the roll being driven by a motor. The interior of the roll is preferably provided with a perforated air tube or pipeline, from which issues uniform air pressurization of the spinning roll vessel. By providing differential speed of the roll in contrast to the line speed of the wet plastic composition and different air pressurization of the roll, a wide variety of textures may be produced on the surface of the wet plastic acoustical composition. |
