Abstract: The calculation and analysis for extruded reducing tees subjected to internal pressure were carried out using ANSYS software．The stress distributions law about the tee were obtained， and verified in combination with the corresponding references．The results show that the fillet radiuses have apparent effects on the tee strength ．A high stress concentration crops up in the corner，and a quadratic curve relation between the maximum stress and inner radius appears when the outer radius was given． Based on the results and related documents， empirical correlation for calculating the maximum stress of the extruded tee is put forward ．

Key words: Extruded reducing tee , Finite element method , Stress analysis

摘要： 应用ANSYS 分析软件对内压作用下大异径挤压三通进行了应力计算和分析，得到了该三通模型的
应力分布规律的数值结果，用理论计算结果验证了有限元分析结果的可靠性，给出了挤压三通肩部转角半径大小对三通强度的影响。结果表明，三通在主支管相贯处应力集中程度很高；当外转角给定时，最大应力与内转角近似成二次曲线关系。根据计算结果及相关文献，提出了计算挤压三通最大应力的经验关联式。

关键词: 挤压三通 , 有限元法 , 应力分析