Theoretical Calculation of Interface Pressure Between Cables and Accessories Within a Wide Temperature Range

The interface pressure between cables and accessories plays a crucial role in the long-term reliable operation of cable systems. However, the mechanism of interface pressure at variable temperature is still inconclusive. In this study, the changes of interface pressure at variable temperature mainly caused by three influencing factors were investigated through theoretical analysis and experimental measurements. The results revealed that the thermal expansion effect will result in a decrease in interface pressure, while the Gough-Joule effect of rubber materials at high temperature will lead to an increase in interface pressure as the temperature rises. Additionally, the stress relaxation effect of rubber-like materials at higher temperature will accelerate the decline in interface pressure. Finally, the interface pressure at variable temperature is calculated based on the comprehensive effect of the three factors. The results showed that the interface pressure increases as the temperature rises, indicating that the Gough-Joule effect of rubber materials dominates the change in interface pressure. The error between the theoretical calculation and actual measurement of interface pressure was <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$&lt;5 \%$</tex>. Therefore, this method can feasibly be used to predict the interface pressure as the temperature changes.