Transfer function Law and diagnosis method of large vibrating screen lower beam with crack flaw

摘要

Vibrating screen is the one of key equipments incoal preparation industry. It is difficult of acquisition ofcondition signal and feature extraction of crack fault becauseof the structure features of the vibrating screen lower beam.So there is no effective method to diagnose the crack fault ofthe vibrating screen lower beam at home and abroad. Thispaper studied and put forward a estimation method ontransfer function, experimentally researched the transferfunction of the vibrating screen lower beam with various crackdepth condition, derived the "shift down evolution regularity"of vibrating screen lower beam transfer function with crackemergence and propagation, proposed the diagnosis methodand judgment rules of large vibrating screen lower beam crackflaw based on the regularity. Test approval results suggestedits correctness and validity of the theory and method.