摘要
通过宏观检查、金相检验、显微硬度测试和扫描电镜观察分析等试验手段对某电厂超超临界锅炉末级过热器T92管爆裂原因进行分析。分析结果表明:爆裂是由于管子内壁存在制造过程中形成的、深度超过管子壁厚一半的裂纹性缺陷,使管子有效壁厚减小,并在缺陷底部和端部形成应力集中,在机组运行过程裂纹逐渐扩展,导致管子开裂失效。
This paper analyzes burst reason for T92 tube of final superheater of supercritical boiler of one power plant by tes- ting methods of macro examination, metallographic examination, microhardness test and scanning electron microscope ob- servation analysis. The analysis result shows that burst of the tube is caused for reasons of crack disfigurement with depth ex- ceeding half wall thickness of the tube which is formed during the course of manufacture in wall of the tube. This kind of disfigurement results in reduction of effective wall thickness of the tube, forming stress concentration at the bottom and end of the defect. In the process of operation of the unit, this flaw may expand gradually and cause the tube to burst and become invalid.
出处
《广东电力》
2013年第3期99-103,共5页
Guangdong Electric Power
关键词
超超临界锅炉
末级过热器
T92钢
爆管
AC/DC hybrid system
static voltage stability analysis
modal analysis method
weak area
