Vibroacoustic processes of grinding fibrous semi-finished products in the knife refiners

Vibroacoustic processes during refining in knife refiners are investigated. When the rotor blades move relative to the stator knives, pressure pulses occur that act on the fibrous semi-finished product, causing it to refine, and on the rotor and stator, causing them to vibrate. A technique has been developed for calculating the sliding speed of the rotor knives on the stator knives. The sliding speed of the knives depends on the headset pattern and the rotor speed and can reach the speed of sound in the metal. The necessity of taking into account the Doppler effect during vibration diagnostics and controlling the functioning of mills is shown. The error in calculating headset frequencies without taking into account the above effect can reach more than 40%, taking into account up to 8%.