吉林电网“三跨”耐张线夹X射线检测及缺陷分析

X-ray Detection and Defect Analysis of Three-span Strain Clamp in Jilin Power Grid

架空输电线路"三跨"区段耐张线夹的压接可靠性是影响其安全稳定运行的重要因素。基于X射线无损检测技术开展吉林电网"三跨"区段耐张线夹X射线检测,共检测332处,发现576个缺陷。缺陷为多压、漏压、欠压和工艺性压接缺陷等4类,其中漏压数量最多,占比达到52%;按照电压等级统计分析,500 kV耐张线夹缺陷数量最多,占比40.8%。通过分析不同缺陷产生的原因,提出有针对性的措施,当耐张线夹存在漏压、欠压等质量缺陷时,应采取开断重压、补压及预绞丝加强等方式进行处理,对"三跨"区段,每隔4年或根据运行工况变化进行复检,确保架空输电线路"三跨"安全稳定运行。

The crimping reliability of the three-span strain clamp is an important factors for the safe operation of overhead transmission lines.X-ray detection technology is used to check the three-span strain clamps in jilin power grid.A total of 332 defects were detected and 576 defects were found.There are four types of defects,including misaligned crimping,unpressurized crimping,incomplete crimping and technological crimping defects,among which the unpressurized crimping is the most,accounting for 52%.According to the statistical analysis of voltage level,the defects of 500 kV strain clamp are the most,accounting for 40.8%.Based on the analysis of the causes of different defects,this paper puts forward some targeted measures.When there are quality defects such as unpressurized crimping and incomplete crimping in the strain clamps,the methods of breaking heavy crimping,supplementary crimping and pre twisted wire strengthening shall be adopted to deal with them.The three-span section shall be rechecked every four years or according to the change of operation conditions to ensure the safe and stable operation of the three-span overhead transmission line.