机械设备运行可靠性评估的发展与思考  

Developments and Thoughts on Operational Reliability Assessment of Mechanical Equipment

作　　者：何正嘉[1] 曹宏瑞[1] 訾艳阳[1] 李兵[1] 

机构地区：[1]西安交通大学机械制造系统工程国家重点实验室,西安710049

出　　处：《机械工程学报》2014年第2期171-186,共16页Journal of Mechanical Engineering

基　　金：国家自然科学基金重点(51035007);高等学校博士点优先发展基金(20110201130001);国家重点基础研究发展计划(973计划;2011CB706805)资助项目

摘　　要：针对某台具体的机械设备进行运行可靠性评估是个性问题,基于大样本条件并依赖概率统计数据得到的平均可靠性难以满足个体设备的运行可靠性评估需求。归纳传统可靠性理论应用于机械设备运行可靠性评估时面临的问题,回顾相应的改进方法。阐述以动态建模与故障机理分析、信号处理与故障特征提取为理论基础的机械设备运行可靠性的技术内涵,赋予运行可靠性新的含义,定义运行可靠度。提出基于机械设备状态信息的运行可靠性评估方法,通过建立设备运行状态信息与可靠性之间的映射模型,实现运行可靠度的计算。参考国际标准ISO3945,将评价回转机械运行状态的绝对振动量转换为量纲一的可靠度指标;对轴瓦松动维修前后两种状态下的汽轮发电机组、连续运行退化至失效状态下的滚动轴承分别进行运行可靠性评估,取得了良好效果。引出机械设备运行可靠性评估有待解决的问题,为后续研究提供参考。Operational reliability assessment of the specified mechanical equipment is an individual problem. The average reliability, obtained by using probability statistics method with large sample data, cannot fulfil requirements of operating reliability evaluation for individual equipment.The emerged problems are summarized when the traditional reliability theory is applied to operational reliability assessment of mechanical equipment, and corresponding improved methods are reviewed. The theoretical basis and technical connotation of operational reliability assessment for individual equipment, which is based on dynamic modelling, fault mechanism analysis, signal processing and fault feature extraction, are expounded. Then, a new concept of operational reliability is given and the degree of operational reliability is defined. An operational reliability assessment approach based on running condition information of mechanical equipment is proposed. Mapping models between running condition and operational reliability is established for mechanical equipment to calculate the degree of operational reliability. Based on ISO3945, absolute vibration values which are used to evaluate running condition of rotating machinery are transformed to reliability degree. The proposed method is applied to a turbogenerator set with bearing bush looseness before/after repair, and rolling bearings which degrade from normal to failure state under continuous running condition. Good results are achieved, which validate the method. The unsolved problems for operational reliability assessment of mechanical equipment are brought up, which may provide reference for the further research.

关 键 词：机械设备 故障机理 特征提取 运行可靠性 运行可靠度 

分 类 号：TH17[机械工程—机械制造及自动化]