Axle is one of the most important parts related to the safety of trailer’s operation on the railroad. In China, the checking of axles is mainly through visual inspection and hammer examinations. The construction of an automation hardware system was simulated by Pro/E, including support, guide rail, sensor, AC servomotor and servo driver conformed to the model. Next, for controlling the operation of the entire system, LabVIEW was used to write a program and to control the rotation of servomotor. The pressure heads controlled by linkage system were utilized to load the axle; meanwhile, through the PCI of NI, the data of pressure and displacement was collected. After calibration, the relative error of pinpointing sensor was 5.207%, and the average relative error was about 1.4%. Analyzed by SPSS, the voltage-load formula's correlation coefficient R is greater than 0.994, while the significance is less than 0.05, showing the regression of great significance. Finally, the capabilities of the simulated axle, such as fatigue, stiffness, intensity and stress, were analyzed carefully.