Abstract: A doctor assembly for doctoring a cylinder (12) includes a doctor blade (17) which is retained at its rear end in a blade holder constituted by a multiplicity of adjacent, narrow pivot plates (15) which are individually pivotable about a shaft (14) that is fixed below a rigid support member (10) that is connected to a main support bar (11), and an inflatable bag (28) is disposed between the pivot plates and the rigid support member (10) so as to enable the pivot plates to pivot relative to one another toward and away from the support member (10) and enable the doctor blade attached thereto to conform to the exact shape of the cylinder (12).

Abstract: Abrasive-containing tobacco slurry is homogenized by passing radially outwards between the facing surfaces of two closely adjacent coaxial rings of tungsten carbide to impinge violently against a tungsten carbide surface surrounding the rings. The occurrence of local areas of wear in the facing surfaces is minimized by rotating one ring relative to the other.