19th Asia-Pacific Vibration Conference (APVC2021)

    The driven lifting mechanism with large- modulus rack-and-pinion-driven lifting mechanism has been used as the core driving device for jack-up offshore lifting platforms and ship lifts due to its large lifting weight, good stability, stable braking, and simple operation. Its operating conditions are complex, the coupling between system components is increasingly enhanced, and the service environment and operating conditions are increasingly complex. When the number of stress cycles increases, different failure modes such as pitting, wear, fatigue crack, bonding, plastic deformation and even broken teeth will appear. This article focuses on the subject of three gorges ship lift scale structures, vertical lifting gear and rack mechanism transmission system working condition of simulated test and research under different working conditions and normal wear gear rack hoisting mechanism of dynamic response characteristics, the gear and rack hoisting mechanism of contact strength and bending strength calculation and static mechanics simulation. The bending stress of the worn gear is calculated as the gear with changed position. Through the measurement and calculation of its basic parameters, the change values of some key parameters are obtained. Then the relevant parameters needed to calculate the bending strength of the worn gear are re-checked. Finally, the bending strength of the tooth root of the worn gear is calculated by the ISO formula. Finally, the bending strength of the worn gear root is verified by comparing with the measured data in the experiment; The dynamic characteristics of the pinion and rack hoisting mechanism were studied by using the dynamic analysis software. The curves of velocity, acceleration and meshing force in the transmission meshing process were obtained, and the interaction and motion rules were studied. Through the theoretical calculation of the strength of gear and rack, static and dynamic simulation, experimental simulation data contrast, the idea of "small push big", theory of big modulus gear and rack design, manufacturing, installation method provides scientific advice, for its fault diagnosis and health assessment to provide the necessary theoretical and experimental basis.