某超临界机组锅炉过热器管爆管原因分析  

Analysis on Bursting Reason of Super-heater Tubes of a Supercritical Boiler

作　　者：蒙新明[1] 张路[1] 赖云亭[1] 於旻 张国栋[1] 

机构地区：[1]苏州热工研究院有限公司,苏州215004

出　　处：《理化检验（物理分册）》2015年第5期353-357,共5页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：通过化学成分分析、力学性能测试、宏观和微观检验等手段对某电厂末级过热器T91钢管爆裂的原因进行了分析。结果表明:爆管具有短时超温运行的特征,爆口附近发生明显的塑性变形,材料显微组织老化严重,力学性能显著下降。导致爆管超温运行的原因可能是两异径管接头处焊瘤和管内壁剥落的氧化皮在下弯头处堆积造成高温蒸汽堵塞,从而引起管壁局部短时超温。The bursting reason of a final super-heater T91 steel tube in a power plant was analyzed through chemical composition analysis, mechanical property testing, macro and micro examination. The results showed that, the burst tube had characteristics of overheat operation for short term, obvious plastic deformation was happened, the microstructure of the material aged seriously, and the mechanical properties decreased significantly near the burst mouth. The reason of overheat operation in the burst tube was possibly that, high temperature steam was blocked by weld headings of the joint between two different diameter tubes and oxide skin spalling from the tube wall accumulated at the elbow tube, thus overheat operation for short term was caused in the tube local wall.

关 键 词：锅炉 过热器 T91钢管 爆管 超温运行 氧化皮 

分 类 号：TM621.2[电气工程—电力系统及自动化]