Abstract: A method for controlling the flow in a shot-peening apparatus, comprising an auger having an inlet supplied with granular media via a hopper, the auger preferably being driven by a stepping motor, for advancing the media fed into the inlet at a precisely controlled rate to a discharge conduit. The motor is controlled by a computer to cause a programmed amount of flow to discharge from the discharge conduit. A proximity sensor, preferably of the capacitive type, is provided in the discharge conduit to detect if the discharge is blocked. The motor and auger may be replaced by a vibrating feeder.