10kV输电线路抱箍断裂事故原因分析

针对10 kV输电线路运行中发生的抱箍断裂事故,采取宏观检查、化学成分、金相组织、力学性能检测方法,分析造成断裂的原因并提出改进措施。分析结果表明:由于抱箍母材中存在网状的三次渗碳体,易发生脆性断裂,抱箍加劲板焊缝处又存在未焊透缺陷,运行中在弯曲应力的作用下形成应力集中,导致未焊透处开裂,最终发生了脆性断裂。

Cause analysis on hoop fracture accident on 10 kV power transmission line

Aiming at the accident of hoop fracture happened in the operation of 10 kV powertransmission line, by the methods of macroscopic inspection, chemical composition test,metallographic test and mechanical property test,analyzes the fracture causes and puts forwardimprovement measure. The analysis result shows that due to netlike tertiary cementite existed in thematerial of hoop, brittle fracture take place easy, and the weld lack of penetration defect existed on thestiffening plate of hoop, forms stress concentration under the action of bending stress, led to the placeof weld lack of penetration to occur crack, eventually causes the brittle fracture.