旋压皮带轮的疲劳裂纹扩展寿命计算

Residual Life Calculation of Fatigue Crack Growth of Spinning Pulley

基于线弹性断裂力学理论,利用Workbench有限元软件在旋压皮带轮拉应力最大处建立沿周向的初始裂纹的三维有限元模型,计算了该模型的裂纹前缘应力强度因子,得到旋压皮带轮以Ⅰ类为主的张开型裂纹类型结论;接着建立不同裂纹扩展模型,仿真计算得到各裂纹前缘的应力强度因子和应力强度因子幅;根据Paris经验公式和拟合后ΔK-a曲线计算,得到了旋压皮带轮裂纹扩展寿命。该计算裂纹扩展寿命的方法为旋压皮带轮的安全设计提供了一种新途径,具有积极的参考意义。

The initial crack along the circumferential extension model of spinning pulley is established by using workbench based on the theory of linear elastic fracture mechanics, and the stress intensity factors of the crack front are calculated. The conclusion is drawn that the type of cracked in spinning pulleys is opening crack. Then, the different crack growth models of spinning pulley are established, the stress intensity factors of crack front and the amplitudeAK of stress intensity factor are calculated. According to Paris formula and the curve of AK-a, the residual life of fatigue crack growth in the spinning pulley is calculated. The method pro- vides a new way of calculating residual life of fatigue crack growth, with positive reference value for the safety design in the spinning pulley.