Analysis of mechanical stresses in silicone rubber joint tubes using a hyper-elastic model

Abstract

A 2D model of a silicone rubber joint tube is proposed to calculate mechanical pressure. An analysis of radial and circumferential stresses within a joint tube based on a hyper-elastic model, employing finite element method is presented. This paper shows that assuming a constant elastic modulus for rubber leads to miscalculation of stresses within the joint tube. In addition, restricting the expansion ratio without considering the material’s elasticity could elevate the possibility of introducing high circumferential stress. Depending on the elastic modulus and expansion ratio, these circumferential stresses may approach 50% of the material’s tensile strength however, none of the simulated materials showed any critical values. A rigid semiconducting deflector could potentially generate significant circumferential stress, especially at the deflector-joint insulation interface, posing an increased risk if the material is relatively weak. Achieving the required pressure with stiffer materials necessitates a lower expansion ratio, while softer materials demand higher expansion ratios to accomplish the necessary pressure levels.