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.

Railway axles are among critical components ensuring safe and efficient train operations. They are particularly susceptible to damage mechanisms such as fretting wear and fatigue. Fretting induced by high contact pressure and microslip between contact surface can significantly deteriorate fatigue strength at the contact edge of the press-fit section. Recent research has been conducted to enhance axle strength and reliability. However, fretting wear or microcrack formation at the wheel-press-fit zone of axles is still an active area of investigation. Accurately analyzing fretting wear is challenging due to its sensitivity to numerous factors such as changes in friction coefficient, influence of wear particles, and selection of an appropriate wear model. This paper aimed to establish a comprehensive analysis method for fretting wear in interference-fitted axles using finite element analysis (FEA) and numerical analysis techniques. Two wear models were applied in simulations: an Archard wear model and an energy-based wear model. Analysis results were compared with experimental data from rotating bending fatigue press-fit specimens. This comparison will help validate the proposed analysis method and assess the effectiveness and accuracy of different wear models in predicting fretting wear in press-fit axles.

Precise installation of a seam clamp is crucial as failure to do so will lead to defects, compromising the quality of paper containers. Even experts spend 90-120 minutes, which comprises 4.7 percent -6.25 percent of the replacement and adjustment process on a paper container manufacturing machine. To overcome an undesirable replacement procedure, a composite seam clamp was devised. The objective of this paper is to enhance the quality of a seam of a paper container and reduce time replacing seam clamps. The composite seam clamp was designed based on the Guerin process. Silicon rubber, which can be used in the temperature range of the paper container manufacturing process (110-130℃), was selected. To validate performance of the steel and composite seam clamp, 13 error situations resulted from translation and rotating misalignment of seam clamps were set and simulated. Through FEM (Finite Element Method) simulation, this paper confirms that the composite seam clamp shows higher transmission of clamping pressure compared to steel seam clamps in error situations. The feasibility of the composite seam clamp was validated in reducing replacement time of seam clamps through on-site tests.