The System Study Of Rotating Bending Fatigue Machine

The current situation of hydraulic tube rotating bending fatigue machine now used in our contry are out-dated loading calibration method.lower test efficiency,automatic and intelligent level and unable to realize process control.To solve the problems,a new system of rotating bending fatigue test is studied and designed in this paper.This paper analyzes the actual working condition of the aircraft hydraulic tube and fittings, establishes mechanical model and analyzes the bending moment on the tube, uses stress analysis method to study the fatigue problems on it. contrasts classic bending fatigue test enginery of rotating test principle, researches the development situation of domestic and foreign tester technology, combes the basic method of hydraulic tube bending test described in the HB6442-90, puts forward the whole scheme of a new rotating bending fatigue test system.In This plan, through the way of offset loading then calibrate strain to load bending moment for specimen. The offset loading devices and self-centering structures and the strain real-time measurement modules is designed to solve the problem of unable to load calibration on the traditional rotating bending fatigue tester. Closed servo control technology is adopted to realize multiple motor stepless speed regulation. Based on Labview. the man-machine dialogue window is made on the PC,to realize the early state of static and dynamic calibration, set the testing time, test speed, monitor test process and judge fault, automatic stop, automatically preserve and process data and so on. Using ANSYS stress analysis software to simulate actual stress and strain distribution of test pieces, and then cloud picture and distribution curve is obtained.