焦炭塔的疲劳累积损伤及套合效应研究  

FATIGUE CUMULATIVE DAMAGE AND NESTED EFFECT RESEARCH OF COKE DRUM

作　　者：朱成诚 赵建平[1] ZHU ChengCheng;ZHAO JianPing(School of Mechanical And Power Engineering, Nanjing Tech University, Nanjing 211816, China)

机构地区：[1]南京工业大学机械与动力工程学院,南京211816

出　　处：《机械强度》2018年第2期424-430,共7页Journal of Mechanical Strength

摘　　要：基于Abaqus平台的二次开发,对典型工况下焦炭塔一个周期的瞬态温度场进行了数值模拟,对进油、进水阶段的径向、轴向温差进行了对比分析,并解释了周向、轴向热应力形成机理;在考虑焦炭与塔壁套合效应的基础上,对Mises应力最大节点进行了组合应力分析,发现焦炭塔在整个生产周期中几乎都处于比例加载状态;鉴于此,通过RainFlow循环计数法对非恒幅应力波形进行了划分,根据疲劳损伤的线性累积原则,计算出了角焊缝的理论寿命值;将有焦炭时的轴向、周向应力值与无焦炭时的进行了对比分析,发现焦炭对塔壁周向套合效应显著,应力增幅近50%;并对套合引起的周向应力进行了理论公式计算,得到了与有限元计算吻合的结果,表明了有限元计算的有效性。A numerical simulation of transient temperature and stress field for a typical coke drum has been done in this paper by Abaqus secondary development. According to the result of simulation,a comparative analysis was done to explain the mechanism of circumferential and axial thermal stress. Under the considering of nested effect between coke and shell,the element node with a maximum Mises value was fond under a condition of proportional loading by the method of combined stress analysis.Based on the principle of the linear accumulation of fatigue damage,in order to calculate the theory life of the fillet weld connecting the skirt and conical head,the combined stress wave of the node before was divided into several whole cycles with Rain-Flow method. After that,when not considering of the nested effect,it is found that the circumferential stress would have a nearly 50 percent lower than the value calculated with nested effect considering. At last, a theoretical calculation of circumferential stress was carried on. It shows that the result given by FEA agrees reasonably well with the theoretical calculation value. Obviously,the result given by FEA was credible.

关 键 词：焦炭塔 应力分析 疲劳累积损伤 套合效应 Rain-Flow法 

分 类 号：TH123[机械工程—机械设计及理论] O346.2[理学—固体力学]