长期冷热循环对电缆附件界面压力的影响

Influence of Long-term Cooling and Heating Cycles on Interface Pressure of Cable Accessories

电缆附件与本体之间的界面压力是影响电缆稳定运行的关键,为探究长期冷热循环对电缆附件界面压力的影响,设计了界面压力测试系统,采用冷热循环的温度控制方式模拟电缆冷热负荷运行状态进行冷热循环实验,并对实验前后的电缆附件硅橡胶材料进行了动态热机械分析。结果表明:长期冷热循环下的硅橡胶材料在测试温度段下弹性模量明显上升。此外,随着老化时间延长、老化温度升高,电缆附件产生不可恢复的形变,导致界面压力降低,界面密封性能下降。基于电缆附件参数对界面压力进行有限元仿真验证了实验结果。

The interface pressure between the cable accessories and the body is the key to the stable operation of the cable. In order to study the influence of long-term cooling and heating cycles on the interface pressure of cable accessories, we designed a test system to simulate the operation state of cable using the temperature control mode of cooling and heating cycles. The dynamic thermo-mechanical analysis of silicone rubber materials before and after the experiment was carried out. The results show that the elastic modulus of silicone rubber material under long-term cooling and heating cycles increases significantly at the test temperature. In addition, with the increase of ageing time and ageing temperature, cable accessories deform irreversibly, resulting in the decrease of interface pressure and the sealing performance. The experimental results are verified by finite element simulation of interface pressure based on cable accessory parameters.