机械密封界面摩擦声发射信号的特征提取与分析  

Feature extraction and analysis of friction acoustic emission signal at mechanical seal interface

作　　者：陆俊杰 刘柱 丁俊华 高德 丁雪兴[2] LU Junjie;LIU Zhu;DING Junhua;GAO De;DING Xuexing(Ningbo Key Laboratory of Advanced Seal,NingboTech University,Ningbo 315100,China;School of Petrochemical Technology,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]浙大宁波理工学院宁波市极端密封重点实验室,浙江宁波315100 [2]兰州理工大学石油化工学院,甘肃兰州730050

出　　处：《振动工程学报》2025年第2期411-419,共9页Journal of Vibration Engineering

基　　金：浙江省自然科学基金资助项目(LY22E050010);宁波市自然科学基金-青年博士创新研究项目(2022J152);国家自然科学基金资助项目(51905480);“科技创新2025”重大专项(2022Z007,2022Z054);固体润滑国家重点实验室基金项目(LSL-1912)。

摘　　要：机械密封非正常接触状况下的高频摩擦信号识别与诊断研究较为匮乏,因此采用高频宽域与强灵敏的声发射技术,搭建密封监测试验台,采集机械密封启停、无压、低压、高压、低速、高速等运行状况下的声发射信号。使用时域、频域和时频域分析方法处理试验数据,进行测试,并建立基于AE信号均方根(RMS)值变化判定机械密封界面摩擦状态的方法,揭示了机械密封从接触式到非接触式过程中的端面摩擦信号与运行状态的对应关系,进一步探明了密封运行过程中,从端面接触摩擦的边界润滑(BL)与混合润滑(ML),逐渐转变为非接触下流体动力润滑(HL)状态的滑动接触信号演变规律,获取了密封界面摩擦时的AE信号频率带范围(240~320 kHz),并通过对AE信号进行时频分析,发现了连续小波变换(CWT)能有效表征机械密封不同工况下的AE信号时频特征信息。本文研究结果为机械密封状态监测和故障诊断的研究提供了理论基础和数据支撑。Research on the identification and diagnosis of high-frequency friction signals under abnormal contact conditions of me-chanical seals is limited.Therefore,a seal monitoring test-bed is established using high-frequency,wide-range,and highly sensi-tive acoustic emission(AE)technology.Acoustic emission signals are collected under various operating conditions of the mechani-cal seal,including start-stop,no pressure,low pressure,high pressure,low speed,and high speed.Then the collected data are processed and analyzed using time-domain,frequency-domain and time-frequency-domain analysis methods.A method for deter-mining the interface friction state of the mechanical seal,based on the root mean square(RMS)change of the AE signal,is estab-lished.This method reveals the corresponding relationship between the end-face friction signal and the running state of the mechani-cal seal,from contact to non-contact,and further proves the seal operation process.The research identifies the evolution of the fric-tion signal during the transition from boundary lubrication(BL)and mixed lubrication(ML)in end-face contact friction to sliding contact signals under non-contact hydrodynamic lubrication(HL).The frequency band of the AE signal during seal interface fric-tion is found to be between 240 kHz and 320 kHz.Through time-frequency analysis of the AE signal,it is shown that continuous wavelet transform(CWT)effectively represents the time-frequency characteristics of the AE signal under different working condi-tions of the mechanical seal.The research results of this paper provide a theoretical foundation and data support for research on me-chanical seal condition monitoring and fault diagnosis.

关 键 词：机械密封 声发射 摩擦 状态识别 

分 类 号：TH136[机械工程—机械制造及自动化] O422[理学—声学]