Application And Research Of Fiber Optic Acoustic Emission Monitoring Technology For Large Cranes Local Damage

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.