Abstract: According to the high cost and long period of the fatigue test for the vertical ring of the scraper chains in the scraper conveyor, the multimedia dynamics software was applied to establish a rigid-flexible coupling dynamics model of the chain riving system.A similar calculation was firstly conducted on the typical performan ces, the stress cloud diagram of each simulation time for the vertical ring was obtained and the dangerous point was determined.Then the load stress time history of the dangerous point was picked up.According to the mission cross section of the scraper conveyor, a load process could be conducted and the load spectrum of the service life calculation could be obtained.Finally according to the linear fatigue failure accumulation law, the fatigue service life of the vertical ring dangerous point could be cal culated and the circulated numbers under the mission cross section of the vertical ring were obtained.The virtual prototype technology could be applied to the prediction of the fatigue service life of the chain ring, thus could reduce the fatigue test cost and could provide the technical base for the fatigue test of the whole machine in the n ear future.