Working Principle and Test Method of Ervin Life Testing Machine with Cast Steel Shot

Through splitting the experiment of Ervin life test machine to study working principle, the initial velocity of the steel shots and throwing device on the basis of collision mechanics was figured out. The results show that, at the outer edge of the throwing device, the initial velocity of the steel shots is 61.8m/s. The initial velocity of steel shots depends on the location of the contact point, the closer the distance between the center position, the smaller the velocity of the steel shots,the larger on the contrary. By testing of cast steel shot and comparing the applicability of the two test methods, the results show that, to study the Ervin life of the cast steel shot, shall use the 100% replacement method, while to study the optimal heat treatment parameters shall usually use damaged curve method.