循环流化床锅炉高温屏式过热器变形原因分析

Analysis on Deformation of the High Temperature Platen Superheater in Circulating Fluidized Bed Boiler

某型循环流化床锅炉内部检验时发现炉膛高温屏式过热器均产生严重弯曲变形,测量其最大挠度约为800 mm。经现场检测,管材厚度、材质均没有明显变化。查阅锅炉技术资料和运行数据分析得出不合理的设计及运行工况是其产生屈曲和塑性变形的主要原因,并通过材料力学理论推导和有限元数值模拟给出了最大变形量的计算公式以及最小失稳应力值,最后提出了几点解决措施方案。

During the internal inspection of a certain type of circulating fluidized bed boiler, it was found that the high temperature platen superheater had serious bending deformation, and the maximum deflection measured was about 800 mm. There is no significant change about the material and pipe thickness after on-site inspection. By analyzing the boiler technical and operating data, it is concluded that unreasonable design and operating conditions are the main reasons for its buckling and plastic deformation. The calculation formula of the maximum deformation and the minimum instability stress value are given through the derivation of material mechanics theory and the finite element numerical simulation. Finally several solutions are proposed.