摘要
动力固结时频繁的大载荷卸载是起重机结构损伤、故障率高的主要原因。针对动力固结冲击大、设备寿命低的问题,探讨了起重机卸载冲击机理,提出了通过卸载器耗能降低卸载冲击的新方法。研究了起重机-重锤模型中系统能量转移规律,提出了柔性卸载原理,建立了描述柔性卸载关键参数的数学模型。根据多体动力学基本理论,建立了起重机的刚柔耦合模型,仿真预测了卸载时间与冲击响应之间的关系,验证了柔性卸载理论模型。根据柔性卸载理论,在起重机与重锤之间设计了基于力控的柔性卸载器,将悬吊拉力控制转变为液压力控制。通过突然卸载与柔性卸载的对比试验,证明柔性卸载显著延长了卸载时间,柔性卸载装置可行,为一类冲击机械减振设计提供了参考。
Frequent large load unloading during dynamic consolidation is the main reason for damage and high failure rate of crane structure.Here,aiming at problems of large impact of dynamic consolidation and low equipment life,the unloading impact mechanism of cranes was explored,and a new method to reduce unloading impact through energy dissipation of unloader was proposed.The energy transfer law of the whole system in a crane-hammer model was studied,the principle of flexible unloading was proposed,and the mathematical model to describe key parameters of flexible unloading was established.According to the basic theory of multi-body dynamics,the rigid-flexible coupled model of crane was established,the relationship between unloading time and impact response was simulated and predicted to verify the flexible unloading theoretical model.According to the flexible unloading theory,a flexible unloader based on force control was designed between crane and hammer to convert the suspension tension control into hydraulic pressure control.Through contrastive tests of sudden unloading and flexible unloading,it was shown that flexible unloading significantly prolongs unloading time;the designed flexible unloading device is feasible;the study results can provide a reference for vibration reduction design of a kind of impact machinery.
作者
刘洋
LIU Yang(College of Engineering and Design,Hunan Normal University,Changsha 410081,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2022年第7期207-213,共7页
Journal of Vibration and Shock
基金
国家留学基金(201908430262)。
关键词
动力固结
柔性卸载
刚柔耦合
数学模型
力控机构
dynamic compaction
flexible unloading
rigid-flexible coupling
mathematical model
force control mechanism
