Transfer Function Law and Diagnosis Method of Large Vibrating Screen Lower Beam with Crack Flaw

Vibrating screen is the one of key equipments in coal preparation industry. It is difficult of acquisition of condition signal and feature extraction of crack fault because of the structure features of the vibrating screen lower beam. So there is no effective method to diagnose the crack fault of the vibrating screen lower beam at home and abroad. This paper studied and put forward a estimation method on transfer function, experimentally researched the transfer function of the vibrating screen lower beam with various crack depth condition, derived the “shift down evolution regularity” of vibrating screen lower beam transfer function with crack emergence and propagation, proposed the diagnosis method and judgment rules of large vibrating screen lower beam crack flaw based on the regularity. Test approval results suggested its correctness and validity of the theory and method.