随机激励下采煤机行走方向的振动特性分析

Vibration analysis of shearer along the walking direction under random excitation

采用理论分析与试验相结合的方法研究了采煤机在行走方向上的振动特性。分析了采煤机工作过程中的滚筒随机截割载荷、行走非线性驱动载荷、摩擦载荷,再以这3个载荷作为工况激励,建立了采煤机5自由度非线性振动方程,分析了采煤机行走方向的振动特性。结果表明:采煤机各部件刚度和质量值较大,摇臂和机身的振动特性较为相似;当行走速度为3~6 m/min时,随着行走速度的增加,整机响应振幅随之变大;由相图和庞加莱映射反映出整机振动处于混沌状态。对采煤机振动特性进行了现场试验,试验测得的机身振动加速度有效值为171.83 mm/s2,接近仿真值(156.06 mm/s2),表明采煤机的非线性模型在一定程度上可以视为是准确的。

The Vibration of shearer along the walking direction was analyzed with the combination method of theoretical analysis and test. Random cutting resistance of drum, nonlinear driving load and friction load were analyzed in the shearer working process. These three loads were treated as condition excitation. Five DOF nonlinear vibration equation of shearer were established to analyze the vibration characteristics of shearer along the walking direction. The results showed that the stiffness and quality were greater and the vibration characteristic between rocker arm and fuselage were similar. When walking speed was 3-6 m/rain, the amplitude of shearer was increased with the increase of walking speed. The phase diagram and poincare reflected the chaotic vibration state. Field test of shearer vibration characteristic was performed. Acceleration effective value of fuselage was 171.83 mm/s2, which was close to the simulation value（ 156.03 mm/s2）. The test results showed that the nonlinear model of shearer was accurate to some extent.