不同工况下电站锅炉下集箱热应力循环载荷计算  

Cyclic Thermal Stress Load Calculation for the Underside Header of Power Station Boiler

作　　者：王海波[1,2] 王方[1] 毛富杰 王泽军[1] 武云龙[2] 

机构地区：[1]天津市特种设备监督检验技术研究院,天津300192 [2]天津大学材料科学与工程学院,天津300072

出　　处：《石油化工设备》2012年第A01期3-7,共5页Petro-Chemical Equipment

摘　　要：电站锅炉下集箱受热和支管分布不对称,筒体的温度场与应力场分析十分复杂。运用ANSYS软件建立了锅炉下集箱有限元模型,分别对启炉、运行与停炉3种典型工况下的热应力载荷进行了模拟计算。结果发现,在3种工况条件下,采用有限元方法计算出的热应力都比采用经验公式计算的结果偏大。因此,在频繁启、停炉的情况下,下集箱的实际寿命可能比设计寿命缩短。同时,支管的机械约束作用可对下集箱的热变形和热应力产生明显影响。在锅炉厚壁下集箱的强度设计与疲劳寿命计算过程中,应考虑支管的约束作用。For the underside header of power station, due to both the thermal flow distribution and the structure are irregular, the temperature field and the thermal stress condition are very complicated. Based on the ANSYS software, an FEM model of the underside header was built, the thermal stress load under three typical working conditions, e. g. , the raising pressure stage, the normal operation stage and the shutdown stage, was calculated, respectively. Through the comparison, the results calculated by the empirical formula were smaller than the results calculat- ed by FEM method. So, the actual fatigue life might be shorter than the designed life when the boiler working conditions changed frequently. Besides, the mechanical restriction of the branch pipes on the header has obvious effect on the thermal stress, as well. The restricting effect of the branch pipes must be considered when one designs the structure and life of a header.

关 键 词：电站锅炉 集箱 有限元 热应力 计算 

分 类 号：TK22[动力工程及工程热物理—动力机械及工程]