某电厂锅炉用12Cr1MoVG钢过热器管在使用约17520 h 后发生爆管，为找到爆管的原因，对其进了失效分析。结果表明：该钢管长期在高温环境下服役，基体组织发生了珠光体球化，导致钢管的强度降低；在高温蒸汽环境下，钢管内壁易生成氧化皮，氧化皮的脱落、再生过程循环往复，导致钢管厚度减薄，强度降低；以上两者共同作用使得钢管的强度下降明显；由于蒸汽中含有腐蚀性元素，导致钢管内壁产生腐蚀凹坑，这些凹坑处会产生应力集中，在高温下，当应力集中程度超过钢管的强度后，就发生了爆管。
After operation about 17 520 h,12Cr1MoVG steel superheater tube used in a boiler of a power station cracked.In order to find the burst causes,failure analysis was carried out.The results show that the pearlite in the matrix turned to spheroidization because the tube used at high temperature over a long period of time,which resulted in the decrease of strength of the tube.Under the environment of high temperature vapor,the oxide scale was easily formed on the inner wall of the tube and then broken off because of vapor washing.Circularly,the thickness of the tube was reduced further and the strength significantly decreased at the two combined action. Corrosion pits were found on inner wall of the tube pits because of the corrosive elements in the vapor,and then, the corrosion pits became crack source as a result of stress concentration.If the stress concentration exceeded the strength of the steel tube at high temperature,the tube would burst.
参考文献
| [1] | 敖哲.锅炉水冷壁爆管原因分析[J].理化检验-物理分册,2014(4):296-298. |
| [2] | 谭莹;曹标;陈明;周崎;莫明珍.过热器20G钢管爆裂原因分析[J].金属热处理,2009(9):105-107. |
| [3] | 张而耕;童遂放;王琼琦;关凯书.12Cr1MoV珠光体耐热钢长期服役中碳化物的变化及对性能的影响[J].机械工程材料,2009(9):28-32. |
| [4] | 刘高杰;李希超;任相文.电站高温再热器爆管分析[J].理化检验-物理分册,2003(7):361-363,386. |
| [5] | 马元坤.超超临界锅炉末级过热器T92钢管爆管原因分析[J].理化检验-物理分册,2013(12):834-837. |
| [6] | 鲁玉龙;薛守洪;徐蓓;卫志刚;张利文.火电厂1025T/h锅炉高温过热器爆管分析[J].腐蚀科学与防护技术,2008(3):193-196. |
| [7] | 王建祥;游新民;岳建新;王大刚;梁长平;宋丽霞;徐树德;陈福枝.电站锅炉爆管事故原因分析[J].理化检验-物理分册,2009(1):34-36,57. |
| [8] | 吴进明;李志章.20钢锅炉钢管的断裂及腐蚀穿孔失效[J].金属热处理,2000(5):29-32. |
| [9] | 杨振国;朱基木;吴连生;金忠(告羽);陈天岭.二次过热器炉管的腐蚀损伤分析与表征[J].腐蚀与防护,2004(2):87-90. |
| [10] | 梁秀兰;有移亮;张峥.12Cr1MoV锅炉过热器管长期过热开裂原因分析[J].机械工程学报,2014(8):81-86. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%