Crack Propagation Law And Charateristics Analysis Of Low-speed And Heavy-loaded Gear

Low-speed and heavy-loaded gear transmission systems are widely used in heavy equipment in steel industries.Especially in the transmission process of the converter tilting mechanism plays an irreplaceable role.In extreme conditions,heavy-loaded gears are prone to fatigue microcracks and cause crack propagation until fracture,which causes casualties and economic losses.In order to avoid the early failure of gears,it is necessary to carry out research on crack propagation mechanism and expansion characteristics.In order to study the crack propagation mechanism of low-speed and heavy-loaded gears,the fracture mechanics and extended finite element method are used to research the crack propagation law and expansion characteristics of gears.The numerical simulation analysis of stress intensity factor that the key factors of gear crack propagation is carried out.Firstly,the SolidWorks is used to parametrically model the gears,and the gear assembly is introduced into ANSYS for dynamic meshing contact analysis to obtain the “maximum stress zone”,which is the area between the root circle and the base circle,and is defined as crack initiation zone.Secondly,the effects of cracks at the root of the crack and the crack at the base circle on the intrinsic properties of the crack are analyzed.The occurrence of the crack reduces the natural frequency of the gear.Then,the stress intensity factor of the crack front is solved by ABAQUS.The results show that the type I stress intensity factor is the dominant factor of crack propagation.The influence of crack size,crack shape and load changes on the type I stress intensity factor are further research.Finally,the extended finite element method is used to study the crack propagation law at different initial crack locations and different initial crack angles.The results show that as the initial crack location gradually shifts to the tooth tip,and the crack propagation trajectory gradually moves toward the tooth tip.When the crack inclination angle is 60°,the crack tip displacement is the largest,and the crack is the easiest to expand.The research results are of great significance for developing gear fatigue fracture theory and improving gear service performance.Figure 63;Table 4;Reference 58...