Main Cylinder Design and Casing

Main cylinders are cast iron or steel, with diameters of 1,280–1,300 mm (Rieter C 60: 814 mm, speed up to 900 rpm). Speeds range 250–600 rpm with roundness tolerances maintained within extremely tight limits since the narrowest setting distance (cylinder to doffer) is only about 0.1 mm. Beneath the cylinder, Rieter replaces the traditional slotted grid with a closed sheet metal casing to prevent small air vortexes and improve fibre orientation.