复合绝缘子非应力腐蚀断裂的技术研究

Joint Diagnosis for a Composite Insulator Fracture not Because of the Stress Corrosion

复合绝缘子因其优异特性已呈替代电瓷、玻璃材质绝缘子的趋势,各大厂家、电网设计建设单位针对复合绝缘子的选用、设计、缺陷检测等诸多方面进行了研究和要求,取得了极大的成就。笔者针对一起悬垂复合绝缘子断裂事故,首先通过复合绝缘子常用检测方法(目测法)的检测,初步判定该起事故事故并不是运行中常见的由应力腐蚀所造成的复合绝缘子脆断,并利用电网基建常用检测方法(金相检测、渗透检测和硬度检测)与电网设备检测新技术(射线检测),从金具与芯棒连接处密封、金具材料、芯棒与金具连接方式等方面对事故绝缘子进行技术研究,最终确认事故原因是由于脱冰跳跃导致复合绝缘子受弯折应力过大导致断裂,建议设计单位在设计、选用复合绝缘子的过程中要特别考虑冰害严重地区的微地形、微气象影响因素。

Composite insulator for its excellent characteristics has alternative ceramics, glass material insulator trends. Major manufacturers and power grid design construction unit did lots of for the selection of composite insulators, design, defects detection in many aspects such as the research and demands, and made great achievements. Aiming at a composite insulators fracture accident which was used for an overhead lines, this paper used the composite insulator＇s commonly testing method （appearance testing）, and initially determined that the accident can＇t be in the operation of the stress corrosion. Then we used the power grid infrastructure commonly used test method （metallographic detection, penetration testing and hardness testing） and grid equipment testing new technology （X-ray testing）. The result finally confirmed that the cause of the accident was due to the ice-shedding which take off the ice jump composite insulator by bending stress lead to fracture. It was recommended that the design unit design, selection of the composite insulator process to special consideration on the ice in serious tiny terrain and micro meteorological factors.