变压器油泵螺栓短期内快速锈蚀断裂失效分析

Failure Analysis of Rapid Corrosion Fracture of Bolts on Transformer Oil Pumpin in Short Term

换流变压器油泵由于连接螺栓的锈蚀断裂导致大量喷油。通过宏观检查、光谱分析、力学性能试验、螺栓拉力验算、金相分析、氢含量检测等方法对故障现象进行了分析。结果表明:螺栓短期内快速锈蚀断裂的发生机理主要是应力腐蚀和氢致裂纹。建议加强输变电设备附属部件的抽检监督力度,安装螺栓时必须采用力矩扳手紧固。

Oil injection happened on oil pumpin of converter transformer due to corrosion fracture of the bolts. Through appearance observation, spectral analysis, mechanical performance test, bolts tension checking, metallographic analysis, hydrogen content detection and other methods, the failure of the bolts was analyzed. Results showed that rapid corrosion fracture of bolts in the short time was mainly caused by stress corrosion and hydrogen induced cracking. Therefore, it was recommended to strengthen sampling and supervision intensity of accessory parts of power transmission equipment and the manufacturer should use torque wrench to fasten the bolts.