摘要
在某台锅炉钢架安装过程中30多根材质为20MnTiB的扭剪型高强度螺栓发生了断裂。经对这些螺栓进行宏观及微观断口分析、金相分析和显微硬度试验,并按照有关标准进行了螺栓的紧固轴力和楔负荷等试验,认为由于螺栓制造工艺不当造成显微组织及性能的不均匀,以及部分螺栓紧固轴力过高,从而诱发了螺栓的延迟断裂。对产生延迟断裂的原因进行了分析讨论。
More than 30 high strength bolts made of 20MnTiB had fractured during the assembling process. Through macro and micro fracture analysis, metallurgical analysis, and micrographic hardness test, as well as fastening axial force and wedge load tests of the bolts carried out according to related standards, it is believed that the non - uniformity of microstructure and performance was resulted from imperfect manufacture technology, and overhigh fastening axial force of some bolts may induce delayed fracture of the bolts. The causes leading to delayed fracture have been also analysed and discussed.
出处
《热力发电》
CAS
北大核心
2007年第9期88-91,共4页
Thermal Power Generation
关键词
锅炉
钢架
扭剪型
高强度螺栓
延迟断裂
氢
steel structure
torsion - tangential type
high strength bolt
delayed fracture
hydrogen
