【作者】 许蕾；

【导师】 丁克勤；

【作者基本信息】 中北大学 ， 通信与信息系统， 2012， 硕士

【摘要】 大型起重机是在搬运和装卸中使用的极其关键的设备，因为其自身结构蕴含的危险因素较多，也是极易发生重大安全事故的特种作业机械。随着我国国民经济的快速发展，我国起重机的总量也在快速增长，起重机的工作日趋繁重，事故的发生次数也越来越高，这对人们的生命财产安全构成了很大威胁。起重机的常规检测耗时耗力，无法及时检测到起重机运行过程中所产生的损伤和扩展，而且即使起重机在通过常规检验合格后，正常运行时依然可能产生损伤而导致重大事故发生，因此，对起重机进行有效的实时监测技术研究具有十分重大的意义。门式起重机是大型起重机的常见类型之一，针对上述问题，本文以门式起重机为应用对象，采用声发射监测和光纤传输相结合的技术路线，基于对起重机声发射特性的研究，实现了对门式起重机局部损伤的远程监测。本文首先研究并分析门式起重机金属结构的常见失效模式，比较现有起重机健康监测技术的优缺点，基于声发射检测原理和光纤传输技术理论，结合健康监测的思想，根据起重机金属结构安全监测的需求，提出了基于光纤传输的起重机局部损伤声发射监测技术。然后本文设计了起重机光纤声发射监测系统，详细介绍硬件架构及相应软件模块的设计与实现，该系统能够对起重机金属结构的安全状况进行实时的声发射监测，进行实时分析评估，并根据评估结果及时对异常状态进行报警，以便提醒用户及时维修，达到预防事故发生的目的。本文最后进行了对比实验，验证该系统的可靠性，实验结果表明该监测系统的性能较为理想。然后应用此系统监测常用起重机钢材在拉伸过程中所产生的声发射信号，分析声发射信号的特性以及声发射信号与钢材损伤过程的对应关系，并进一步将系统在起重机上进行试应用。更多还原

【Abstract】 The large crane is the most important equipment during the handling, loading andunloading, also it can easily cause big accidence. With the rapid development of China’snational economy, the total amount of cranes in China is also growing rapidly. The workloadsof the cranes are increasing, and the accidence rate is soaring up, it threatens people’s life andproperty dramatically. Routine testing is time-consuming, labor-intensive, also cannot detectsthe damage initiation and crack propagation in time when the crane is running. Cranes whichthrough routine inspection is still possible to produce injury led to a accident during normalworking. Therefore, to monitor the crane’s health effectively and in time is of greatimportance. To solve this problem, fiber optic acoustic emission monitoring technology isresearched to realize the crane local damage remote monitoring in this paper.First, the paper analysis the common failure mode of the gantry crane metal structure,compares the advantages and disadvantages of the existing cranes health monitoringtechnology, then studies the acoustic emission detection principle, fiber-optic transmissiontechnology, and combines with the idea of health monitoring, designs the crane local damageremote monitoring according to the safety monitoring requirements of crane steel structure.Then, the cranes fiber acoustic emission monitoring system is designed; function of thehardware modules and software modules is described in detail. In order to the purpose ofaccident prevention, the system can carry out real-time acoustic emission monitoring,real-time analysis and evaluation, and alarm when in the abnormal state according to theresults of the assessment.Finally, crane steel tensile test is done in order to validate the system is reliability; theexperimental results show that the performance of the monitoring system is desirable. Weacquired the acoustic emission signals generated during stretching process by this monitoringsystem, and analyzed characteristics of acoustic emission signals. Also we analyzed thecorresponding relations of the acoustic emission signal and steels injury.更多还原