1Cr13除尘风机导流套开裂原因分析及其应对措施

Cause analysis and measures of cracking of flow diversion sleeve of 1Cr13 dust removal fan

某1Cr13除尘风机导流套在使用过程中发生脆性开裂。通过断口宏观形貌分析、金相显微组织分析、化学成分分析及扫描电镜微观形貌分析等方法,对发生脆性开裂的导流套试样进行了失效原因分析。结果表明:导流套开裂是由导流套底侧面的腐蚀坑洞引起的。在含有氯化物、硫化物等腐蚀性介质的环境作用下,导流套底侧面产生缝隙腐蚀,造成导流套底侧面局部出现腐蚀坑洞;在导流套内应力和外界环境的共同作用下,腐蚀坑洞部位产生应力腐蚀及沿晶裂纹,并最终引发导流套脆性开裂。

The flow diversion sleeve of 1Cr13 dust removal fan malfunctioned due to the brittle cracking.Reasons were analyzed by means of fracture analysis,metallographic microstructure observation,chemical composition study and scanning electron microscope examination.The results showed that the cracking was caused by the corrosion potholes on the side of the bottom of the flow diversion sleeve.With corrosive media including chloride and sulfide interacting,crevice corrosion occurs on the bottom side of the guide sleeve,resulting in corrosion potholes on the bottom side of the flow diversion sleeve.In addition,the flow diversion sleeve was subject to the internal stress and external environment,which made the stress corrosion and intergranular cracks happen on the spot of corrosion potholes,resulting in brittle cracking of the flow diversion sleeve.