某电厂中压调节阀杠杆销钉断裂原因分析  

Fracture Analysis for Lever Pin of Medium Pressure Regulating Valve at Power Plant

作　　者：李文彬[1] 冯砚厅[1] 郑相锋[1] 王强 李文鹏[1] 

机构地区：[1]河北省电力公司电力科学研究院,河北石家庄050021

出　　处：《热加工工艺》2013年第18期196-197,199,共3页Hot Working Technology

摘　　要：某电厂620MW超临界空冷机组在进行检修时,发现汽机中压调节阀杠杆销钉断裂。销钉所用材料为20Cr1Mo1VnbTiB,该钢对热处理较敏感,对断裂的销钉取样进行化学成分、金相、断面硬度及冲击试验。结果表明,销钉化学成分合格,金相组织、硬度、冲击功均不满足标准要求;销钉由于结构原因,存在较大应力集中,同时销钉韧性极低,是销钉开裂的主要原因。The fracture of lever pin of turbine medium pressure regulating valve is found undergoing overhaul for 620MW supercritical air-cooling unit at a power plantin a power plant. The pin is made of steel 20Cr1Mo1VnbTiB. The steel is more sensitive to heat treatment. The fracture pin is sampled for the chemical composition, microstructure, hardness and impact test. The test results show that the pin chemical composition is qualified. The microstructure, hardness and impact energy of the samples can not meet the standards. The main reason for crack is the very low toughness and a large concentration of stress is due to the structural reason of the pin.

关 键 词：中压调节阀 销钉 断裂 

分 类 号：TG113.25[金属学及工艺—物理冶金]