Corrosion Diagnosis and Mechanism of Boiler Water-Cooled Wall Tubes in Alkaline Environment

摘要：

　　Failure analysis was carried out to find out the causes of burst on water-cooled wall tubes elbow for circulating fluidized bed (CFB) boiler.Through macro-observations,chemical composition analysis,macro structure observations,grain size measurements and water quality examinations,it can conclude that the high pH value of boiler water at the fire-facing side of weld dense phase zone will lead to alkali concentration that will cause alkali corrosion.The existence of residual stress in elbow under strong alkaline environment will cause alkali stress corrosion.Research results show that the tube failure is caused by both alkali corrosion and alkali stress corrosion.Strengthen water quality monitoring and elimination of stress can effectively prevent the alkali corrosion and alkali stress corrosion.

关键词： Circulating fluidized bed boiler water-cooled wall tubes alkali corrosion alkali stress corrosion failure analysis

作者: Zhenhua ZHOU Dongjian XUE Shengjie QIAN

作者单位: Jiang Nan Road 1588A,Ningbo 315048,China,Ningbo Special Equipment Inspection & Research Institute

会议类型: 国际会议

会议名称: 2016 International Symposium on Structural Integrity，ISSI—2016(2016国际结构完整性研讨会)

会议地点: 天津

会议语种:英文

页码: 488-492

在线出版日期: 2016-05-26（万方平台首次上网日期，不代表论文的发表时间）