在苛刻的作业工况下,焦炭塔运行若干年后会出现筒体鼓胀变形.为解决此问题,文中对焦炭塔的变形机理进行了分析,利用圆柱形壳体弯曲理论求解了焦炭塔筒体在温度应力和内压作用下所产生的内力和位移.利用密席斯屈服准则,可以判定在水冷阶段筒体部分区域进入塑性,产生周期性的塑性残余变形,残余变形随着生焦次数的增加而增加,由此可知,焦炭塔的鼓胀变形主要是渐次塑性变形积累的结果.
In slashing running conditions, the bulging deformation of coke drums may appear after some years. In order to avoid the deformation, this paper analyzes the deformation mechanism of coke drums, and uses the bending theory of cylindrical shell to reveal the internal force and the displacement of the coke drum body suffering from temperature stress and inner compressive force. According to the Mises yield rule, it is found that, as part of the drum body yields during the process of temperature decreasing, a periodical plastic residual deformation occurs and increases with the running cycles of coke drums. It is thus concluded that the bulging deformation of coke drums mainly results from the progressive plastic deformation.