引压管闸阀阀盖螺栓断裂原因分析

Cause Analysis on the Fracture of Valve Cover Bolt of Gate Valve in Press-leading Pipe

通过宏观检查、材质分析、金相分析、扫描电镜等分析手段对某柴油液相加氢装置引压管闸阀的断裂阀盖螺栓进行失效分析。结果表明:断裂螺栓材质不符合标准要求,在沿海工业大气环境和拉应力的共同作用下,发生晶间应力腐蚀开裂。从选材、螺栓腐蚀防护措施等方面提出了改进建议。

The failure analysis on valve cover bolt of gate valve in press-leading pipe of a diesel liquid phase hydrogenation plant was carried out by means of macroscopic inspection,material analysis,metallographic analysis,scanning electron microscopy and other analytical tools.The results show that the material of the broken bolt did not meet the chemical composition standard,and intergranular stress corrosion failure occurred under the combined action of coastal industrial atmospheric environment and tensile stress.The improvement suggestions were put forward from material selection,bolt protection,and so on.