高温下法兰系统温度分布及螺栓载荷变化

摘要

建立了高温下法兰-螺栓-垫片实验装置，采用热电偶测量温度，并采用中温应变片测量螺栓载荷，试验研究不同法兰内壁温度下，各组件的温度分布以及螺栓载荷的变化规律；同时，建立了与试验工况相同的高温法兰稳态热-结构耦合有限元模拟模型，利用试验数据对模拟结果进行了验证。结果表明，高温下沿法兰内壁至法兰外沿会形成明显的温度梯度。法兰内壁、法兰外壁、螺栓、法兰外沿4个位置的温度依次降低。在本试验的法兰、螺栓及垫片属性下，随着法兰内壁温度升高，螺栓载荷降低，且载荷的均匀程度也降低。试验结果与数值模拟结果表明，采用有限元模型研究高温下法兰密封性能是可行的。%The experimental device of flange-bolt-gasket system in high temperature is set up.The ther-mocouples were selected to measure the temperature and the medium temperature strain gauges were a-dapted to test the bolt loads.The temperature distribution and the bolt load changes in high temperature were studied experimentally.Moreover,the thermal-structure coupling finite element model correspond-ing to the structure in experiments was established and verified using experimental results.The results in-dicate that the temperature gradient was formed along the radical direction of flange in high temperature. The temperature of inner surface of flange,outer surface of flange,bolt and outer border of flange decrea-ses successively.With the properties of flanges,bolts and gasket in the experiments,bolt loads decrease with the increase of temperature of inner surface,the same as the uniformity degree of the loads.The com-parison of numerical and experimental results indicates that it is feasible to study the sealing performance of flange-bolt-gasket system in high temperature by using finite element simulation.