【摘要】 研究了某电厂 5 0 0MW锅炉角部撕裂原因。失效形式包括鳍片纵向撕裂和鳍片管断裂。所有开裂均为焊接缺陷如焊缝夹杂、气孔、孤坑、飞溅等处形核。裂纹扩展受切应力影响 ,属Ⅰ Ⅱ型裂纹问题更多还原

【Abstract】 Failure in corner of a 500MW boiler in a power plant has been analyzed. The longitudinal tear along the fin tube welding metal and the shear rupture of the fin tube are presented in the failure. The results indicate that all crackings are initiated from welding defects such as inclusions in position metal, blowholes, arc suppressing pits and splashes and so on. The crack propagation is affected by the shear stress and the fracture is controlled under combination of SIF K Ⅰ-K Ⅱ.更多还原