增压锅炉耐火砖衬结构的断裂失效分析

Fracture Failure Analysis for the Refractory Brick Wall of Supercharged Boiler

针对增压锅炉炉膛耐火砖衬出现横向裂纹的现象,综合考虑耐火砖所承受的热冲击、高温烟气冲刷及机械载荷的复杂工作环境,对局部砖衬结构进行了三维仿真建模,采用有限元方法进行瞬态温度场和应力场计算。结果分析表明:耐火砖衬结构的断裂失效主要是由于增压锅炉快速升、降温过程引起的拉压应力反复作用所致的疲劳损伤,停炉降温过程中的拉应力是引起断裂失效的直接原因。

The paper introduces a phenomenon that wall brick appeared transverse crack. Considering the refractory heat、the impact of high temperature flue gas erosion and mechanical load of the complex working environment. We mainly focus on the Wall Local Lining Structure for study. Build its 3- D models. Using the finite element method to calculate temperature and stress. Through the analysis of wall brick thermal stress concentration phenomenon,get that the crack caused by fatigue damage of the temperature rose and compressive stress repeatedly. The cooling process of its pressure stress is the direct cause for fracture failure,and the type of the crack is Ⅰ.