电动阀电驱动器铜套断裂原因分析

Fracture Analysis on the Copper Sleeve of the Electric Actuator for the Electric Valve

某乙烯装置甲烷再生单元电动阀门电驱动器更换磨损铜套后连续发生铜套断裂现象,采用宏观检查、硬度与冲击试验、金相检验、断口微观观察与能谱分析等方法对铜套失效原因进行分析,结果表明断裂原因是电动阀在超过关限位位置存在卡滞,电驱动器输出较大的驱动力矩,以较大应力作用在材料性能较弱的铅黄铜铜套凸缘和下部梯形螺纹上,发生了凸缘及梯形螺纹的断裂。提出了电驱动器阀门检修的要求。

After replacing the worn copper sleeve on the electric actuator of the electric valve in the methane regeneration un辻of an ethylene plant,the copper sleeve continuously fractured.The failure causes of the copper sleeve were analyzed by means of macro inspection,hardness and impact test,metallographic inspection,fracture micro observation and energy spectrum analysis.The results show that,the reason for fracture is that the electric valve is stuck when exceeding the close limit position,and the electric actuator outputs large driving torque,which acts with large stress on the lead brass copper sleeve flange and lower trapezoidal thread with weak material properties,causing fracture of the flange and trapezoidal thread.The requirements for the maintenance of electric actuator valve are put forward.