CONSIDERATION OF WATERTIGHT PERFORMANCE EVALUATION BASED ON THE MECHANICAL PROPERTIES OF THE LIP OF GLAZING GASKETS

This study focuses on the watertight performance of the lip section of EPDM gaskets. Full-scale water leakage tests and FEM analyses were conducted to quantitatively evaluate the relationship between reaction force and watertightness. Accelerated aging tests showed that combined deformation and high temperature (100°C) reduced lip reaction force by about 50%, causing leakage even at design compression. Watertightness declined significantly when reaction force dropped below 8 N/100 mm. FEM analysis confirmed consistency with experimental results and revealed that lip thickness tolerance had twice the impact on reaction force compared to stiffness. Lip pressure is thus crucial for watertight performance.