Fatigue Fracture Analysis Of Linear Vibrating Screen Beam

Vibrating screen is widely used in mining, coal, petroleum, chemical industry etc. Due to its high screening efficiency, however, the body has to bear a larger alternating excitation force at higher vibrating frequency, so it often appears fatigue damage such as cracking of the beams in practical work. Especially, fatigue damage in the large-scale direction is becoming more severe. It is urgent to improve the fatigue life of the reliability of products in the design stage. So study on fatigue fracture of the beam to improve the reliability of the products is very important.With modern fatigue theory as a foundation, analysis the destruction causes of beam, determine the applicable method of fatigue life analysis of vibrating screen beams. The finite element model of the beam is set up using ANSYS, and analysis of dynamic performance is made, obtained distribution of dynamic response and dangerous position of beams. First proposed a concept of the " partial heavy ratio ", fatigue analysis and life estimation is made when beam working in ideal condition and particular stressed conditions applying the method of stress-life, predict the fatigue life of beam without manufacturing defects in approximate actual situation. In addition, residual life of crackled beam is estimation adopted linear- elastic fracture mechanics method, calculated and drawn the curve of crack length and residual life of beams, gained crack propagation law. Provide scientific methods for fatigue life prediction of vibrating screen beams.By comparing the results of the actual situation, it is showed that the dynamic fatigue analysis results of beams are reliable, illustrated the proposed method has important practical value, for the screen beams safely operation and repair provides important theoretical basis.