摘要
某电厂锅炉主给水管道上的闸阀阀杆在服役过程中发生断裂,采用断口分析、微区能谱分析、化学成分分析、力学性能试验、冲击试验与金相检验等方法,对阀杆断裂原因进行了分析,结果表明阀杆断裂是由于阀杆材料冲击韧性值偏低,同时在制造时退刀槽处未加工倒角,造成开启时阀杆截面突变处应力集中加剧,导致开阀瞬间阀杆在退刀槽处断裂。提出了阀杆材料热处理时应采取正确的装炉方式,并根据实际装炉量确定淬火和回火均热时间及控制产品合格率的热处理过程。
Fracture of gate valve stem used for main water supply pipe of power plant boiler occurred during service process,and means such as fracture analysis,energy spectrum analysis,chemical composition analysis,mechanical property tests,impact testing and metallographic examination were used to analyze the fracture reasons of the valve stem.The results show that the fracture of stem was due to the impact toughness value is low,unmachined chamfer at tool withdrawal groove increase stress concentration of abrupt change in stem section when valve opens,then the valve stem was fractured at tool withdrawal groove at the moment valve opens.In the paper,the correct charging method when the valve stem material is heat treated is put forward.The quenching and tempering soaking time and the heat treatment process to control the qualified rate of the product are determined according to the actual quantity of the furnace.
作者
周丽琴
吕召政
张娜
田骏
沈寒玉
ZHOU Li-qin;LV Zhao-Zheng;ZHANG Na;TIAN Jun SHEN Han-Yu(Wuhan Boiler Group Valve Co.,Ltd.Wuhan 430200,China)
出处
《阀门》
2019年第5期47-50,共4页
VALVE MAGAZINE
