电力电缆运行过程中的热机械性能变化

电力电缆载荷工作时, 处于一定温度, 具有热胀冷缩和塑性变形性能, 因此将产生热机械性能变化, 主要表现为热伸缩和热应力变化, 这严重危害电缆及附件的安全运行。通过对导体与绝缘材料的轴向热伸缩变化和热应力的计算, 研究了热机械性能变化对电缆使用和敷设过程的影响, 简述了电缆及附件在设计、生产及敷设时需采取的措施。

Electric Cable Thermal-Mechanical Property Change during Operation

During normal operation,electric cable will be at a certain temperature,and is capable of thermal deformation and plastic deformation,resulting in thermal-mechanical property changes,which mainly manifest themselves as thermal extension and shrinking and thermal stress variation.It seriously threatens safe operation of cables and accessories.Through conductor and insulating material axial thermal deformation and thermal stress calculations,the effects of thermal-mechanical property change on cable uses and laying processes are studied.Necessary measures during cable and accessory design,manufacturing and laying are also discussed.