焦炭塔的鼓凸损伤分析

焦炭塔的鼓凸损伤问题一直为国内外炼油厂所重视，对鼓凸原因众说不一．鼓凸部分的机械性能及断裂韧性的变化，金相检验、断口扫描电镜等分析表明，材质变化不是鼓凸损伤的主要原因．对塔体各种应力进行了分析和计算，如薄膜应力，蠕变应力和热应力等，发现这些应力不致构成塔体鼓凸最后找出导致塔体鼓凸的主要原因是热油进入塔体使塔体热臌胀，冷却时焦炭的膨胀系数远远小于塔壁，造成了塔壁收缩受约束而产生了较大的残余应力对焦炭的热膨胀系数和弹性模量进行了测定，计算出残余应力值，数值可观，是造成塔体鼓凸的主要原因．

Analysis of the Prominence Failure of Coke Chamber

The causes leading to the prominence failure of coke chamber are analysed. According to the analyses of the changes in conventional mechanical properties, fracture toughness, metallograph and fractography of coke chamber material, it is held that the changes are not the main causes. By calculationg the me mbrane stress, creep stress and thermal stress of chamber body, it is found that they are not great enough to lead to prominence failure. The residual stress is probably main cause produced in the chamber wall whose contraction is restricted when hot oil cools in the chamber. After the thermal expansion coefficient and elastic modulus of coke are measured, the residual stress is calculated. The result shows that its value is great enough to cause the prominence failure of coke chamber.