影响电缆绝缘热延伸性能的因素分析及改进方法

Analysis of Factors Affecting Thermal Extension of Cable Insulation and Improvement Methods

绝缘热延伸性能是架空绝缘电缆和电力电缆的重要试验指标,随着电网技术的发展,配电网对绝缘的热延伸性能要求也越来越高。国家标准要求值为不大于175%,而各省网要求值为不大于125%,因此,加大了电缆企业的生产难度,并有出现电缆绝缘热延伸性能不达标的情况。针对此现象,通过对电缆绝缘的原材料、导体温度、挤塑模具、挤出温度、收线速度、冷却温度、温水交联、试验环节等影响因素进行分析,不断改进生产工艺,对绝缘热延伸影响因素进行多次验证总结,使得电缆在该生产工艺的控制下,低压电缆绝缘热延伸性能完全达到配电网的要求。

Insulation thermal elongation performance is an important test indicator for overhead insulated cables and power cables.With the development of power grid technology,the requirements for insulation thermal elongation performance in distribution networks are also increasing.The national standard requires a value of no more than 175%,while the provincial network requires a value of no more than 125%.Therefore,it increases the production difficulty of cable enterprises and there are cases where the thermal extension performance of cable insulation does not meet the standard.In response to this phenomenon,by analyzing the influencing factors of cable insulation such as raw materials,conductor temperature,extrusion mold,extrusion temperature,take-up speed,cooling temperature,warm water cross-linking,and testing process,the production process is continuously improved.The influencing factors of insulation thermal extension are verified and summarized multiple times,so that under the control of this production process,the insulation thermal extension performance of low-voltage cables fully meets the requirements of the distribution network.