换热器液压胀接接头残余接触压力

Residual contact pressure in hydraulically expanded tube-tubesheet joints of heat exchangers

采用非线性有限元法模拟液压胀接过程,考虑了管子与管板材料、几何尺寸和胀接压力对接头残余接触压力的影响,以正交试验安排计算方案,将所得的数据回归得到了接头残余接触压力估算式,同时给出了液压胀接贴胀压力的计算方法。认为管子与管板材料的匹配关系和胀接压力对接头残余接触压力影响最大,其次是管子与管板孔之间的间隙和管子壁厚、管板厚度影响最小。

The process of hydraulic expansion of tubetubesheet joints was simulated using nonlinear finite element method, and two equations based on data from calculation were developed to evaluate residual contact pressure of joints and the moderate expansion pressure. During the course of calculation, the material property of tube and tubesheet, geometrical size and expansion pressure were taken into account. In order to reduce the number of calculation, orthogonal design method was undertaken. This work shows that material property of tube and tubesheet and expansion pressure are the most important factors to determine residual contact pressure, the radial clearance between tube outside radius and tubesheet hole radius and the thickness of tube have the secondary effect and the thickness of tubesheet is the third important parameter for determining residual contact pressure in hydraulically expanded tubetubesheet joints.