Abstract: A method and apparatus for expanding the fiber column produced by a rotary fiber manufacturing unit and intermingling additive particles with the fibers. A rotating bell-shaped shell is mounted beneath the rotary disc of the manufacturing unit so that the lower portion of the shell is in the path of the fiber column, causing the column to be outwardly deflected. Additive particles are introduced from within or beneath the shell and are radially directed into the fiber column. Liquid binder may be introduced to the fibers and water may be directed onto the inner surface of the shell to cool the shell to prevent curing of binder coming in contact with the shell. The fibers may be glass fibers and the particles may be foamed resin, fibers or particles of various types.

Abstract: A rotary fiberization method and apparatus. Gas and/or liquid may be introduced into the void area produced by a rotary fiberization process. The gas and/or liquid may be used to alter the configuration of the fiber column and to apply desired materials to the fibers.

Abstract: An improved process for the centrifugal spinning of refractory fibers is described. In the improved process rotor circumferential speeds of at least about 21,000 linear feet per minute (6,400 linear meters per minute) are used. In a preferred embodiment the circumferential surfaces of the rotors are also inclined from being perpendicular to the axis of the molten stream, preferably by about 8.degree. to 20.degree..