The invention discloses a test device for evaluating the effect of an oil pumping polished rod
coating upon a fatigue strength, including a three-point bending test
machine, a tension-tension fatigue test
machine and an
analysis sample, the three-point bending test
machine includes a pressure adding roller wheel, a pressure head clip, a three-point bending support and a support roller post, the tension-tension fatigue test machine includes an upper fixture, the pressure adding roller wheel and the pressure head clip of the three-point bending test machine which are arranged into integration in the upper fixture, wherein, the upper fixture connects with a
control system through a sensor and connecting lines, the
analysis sample is horizontally placed on the support roller post of the three-point bending test machine, and the pressure adding roller wheel faces a rod-like fatigue sample. Through combining the
control system of the tension-tension fatigue test machine and the support and the pressure head of the three-point bending test machine, a three-point bending test can be carried out to realize the
simulation of the
bending fatigue process in the scope of 10 centimeters underneath the clip of the oil pumping polished rod in
oil field site, when using the device of the invention, the effect of the
coating upon the fatigue strength can be effectively evaluated.