The use of environmentally friendly, lubricant-free plastic seals in the rotating parts of robots and machines is on the rise. However, variations in seal geometry and operating conditions can influence the contact pressure between the seal and shaft, potentially leading to poor sealing performance, premature wear, or debris ingress. Therefore, advanced design optimization is essential. In this study, we conduct a parametric study and sensitivity analysis to enhance the performance of plastic seals. Finite element analysis (FEA) is carried out using a 2D axisymmetric model with interference fit contact conditions to accurately simulate the behavior of the seal and shaft. We verify the reliability of the analysis by comparing the deformation of the seal diameter before and after shaft insertion with experimental measurements obtained using a 3D tactile measurement device. We analyze four design variables: pressure, temperature, seal diameter, and coefficient of friction, considering seal contact pressure as the objective function. Sensitivity analysis is performed to determine the impact of these design variables on contact pressure and to identify trends.

The brake squeal noise is a high-frequency noise over 1 kHz range generated by the contact between the brake pad and the disk. The purpose of this paper was to investigate the behavior of the squeal noise characteristics of the brake system from an instability point of view, according to the variation of major parameters such as friction coefficient between the flexible pad and the disk, brake pressure, and Young’s modulus of disk. Full nonlinear perturbed modal analysis using commercial finite element analysis program was performed to derive complex eigenvalue results of the model. And the sensitivity behavior was observed. Increasing the coefficient of friction or Young’s modulus of disk tended to make the squeal mode of the model more unstable. However, the change in brake pressure has a complicated nonlinear relationship with the squeal mode of the model. The judgment technique conducted in this study should be considered to be used in the design of the vibration point of the disk and pad of railway vehicles in the future.