某化工厂水煤浆用低压蒸汽发生器RBI检验及缺陷分析

RBI Inspection and Defect Analysis of Low Pressure Steam Generator for Coal Water Slurry in a Chemical Plant

采用基于风险的检验方法对某化工厂低压蒸汽发生器进行检验检测,并对发现缺陷采用宏观检查、金相分析、断口形貌分析和能谱分析等方法进行原因分析,切取试样金相组织未见异常,断口形貌存在初窝断口和解理断裂2种形貌,能谱分析在断口处存在Cl、S等元素,结果表明:设备发生开裂并泄露的主要原因是在运行过程中换热管管口处受应力腐蚀。

The risk-based inspection method was used to inspect the low-pressure steam generator in a chemical plant,and the causes of the defects were analyzed by macroscopic examination,metallographic analysis,fracture morphology analysis and energy spectrum analysis.The metallographic structure of the samples was not abnormal.There were dimple fracture and cleavage fracture in the fracture morphology.There were C1,S elements in the fracture surface by energy spectrum analysis The results show that the main cause of equipment cracking and leakage is the stress corrosion of the heat exchange tube orifice during operation.