Prediction and analysis on fatigue life of flat ring in scraper chain

In order to predict a fatigue failure time of the flat ring applied to the chains of the scraper conveyor,based on the test load data,a prediction of the service life was conducted. Based on a ø38 mm×137 mm C grade type chain ring as the study object,a tensile strain test device was applied to the online monitoring and measuring of the chain tensile to the scraper conveyor. The flat ring strain loading data of the conveyor chains with 10 working periods were obtained. In combination with the tension numerical calibration,rain flow method,Goodman model and other means,a data processing,analysis and average stress correction were conducted on these data obtained. The yield limit of the chain ring material was applied to estimate the fatigue characteristic curve of the chain ring. The study results showed that the shaft shoulder point of the chain flat ring applied to the scraper conveyor would be the weak point of the strength,a stress concentration phenomenon would be easily occurred and the max stress value would be 719.5 MPa. The analysis on the fatigue life of the flat ring showed that the average service life of the chain flat ring applied to the scraper conveyor would be 42 050 circulations and the gearing between the sprocket and the chain link would be 84 100 times. The conclusion could have important reference significances to the structure design and optimization of the scraper chain link as well as the time references to the maintenances and replacement.