潜孔钻机工作装置动力学仿真与疲劳损伤评估研究

RESEARCH ON DYNAMIC SIMULATION AND FATIGUE DAMAGE ASSESSMENT OF THE DOWN-HOLE DRILL WORKING DEVICE

针对潜孔钻机作业过程中关键部位易发生疲劳破坏的问题,基于拉格朗日方程和模态叠加法,建立了潜孔钻机工作装置的多柔体动力学模型,采用虚拟样机技术和ADAMS仿真,实现了潜孔钻机工作装置动力学分析。运用实测荷载谱得到了潜孔钻机工作装置关键部位的应力谱,基于名义应力法,实现了疲劳关注点的疲劳损伤评估。结果表明:包含工作装置运动姿态、钻孔轴压力和回转扭矩载荷的多柔体动力学仿真分析,能够准确获得疲劳关注点的应力,潜孔钻机工作装置上各个油缸与钻臂结构件铰接处和铰支座根部是疲劳破坏最危险位置。采用多柔体动力学仿真获得了各疲劳关注点的应力、疲劳损伤量和疲劳寿命,为工作装置的结构疲劳强度提升和轻量化设计提供了依据。

In order to solve the problem that the key parts of the down-hole drilling rig are prone to fatigue damage,the flexible multi-body dynamic model which can reflect the mechanical characteristics of the down-hole drilling rig working device was established by using Lagrange equation and mode superposition method.Using virtual prototyping technology and ADAMS simulation platform,the dynamic analysis of the working device was realized.The stress spectrum of the key parts of the working device of the down-hole drilling machine was obtained by using the measured load spectrum.Based on the nominal stress method,the fatigue damage assessment was realized.The results showed that the stress of fatigue focus could be accurately obtained by the dynamic simulation of flexible multi-body considering the motion attitude of working device,drilling shaft pressure and rotary torque.The most dangerous position of fatigue damage was the hinge of each oil cylinder and welding part of drill arm and the root of hinge support.The stress,fatigue damage and fatigue life of each fatigue focus point were obtained by flexible multi-body dynamics simulation,which could provide a reference for the structural strength improvement and lightweight design.