Abstract: A method for starting or stopping each of at least two separately controllable roll-sets (22, 26, 34, 56) used for processing a yarn (Y) in a stretch-break process, each roll-set comrpising at least two rolls, the method is characterized by the step of each roll-set, changing the speed of each roll from an initial condition to a steady state condition in accordance with a predetermined sequence and in coordination with a change in speed of at least one of the other rolls, such that simultaneous complete breakage of a yarn (Y) being processed in a stretch-break process is minimized.

Abstract: A pelletizer particularly useful for pelletizing water-dispersible melt-extrudate, among other materials, delivered from an extruder through a die positioned in communication with the interior of the pelletizer housing. The pelletizer includes a rotor disposed inside the housing and knives mounted around the periphery of the rotor. The knives pelletize the melt-extrudate as the rotor rotates. A fluid supply system selectively delivers a fluid, such as air, to the knives when the knives are at a selected location in the housing. The selected location is preferably just past the inlet and can extend in a circumferential direction around the housing in the area of the housing which is near the outlet. The circumferential extent can vary according to the configuration of the knives and the fluid supply system.