针对高强化柴油机活塞,研究了网格数量和活塞销孔棱缘耦合应力的收敛性关系,进行了精确的活塞耦合应力计算；研究了异型销孔结构对活塞应力分布的影响规律；根据耦合应力计算结果,选定异型销孔位置和形状,设计双侧圆锥形异型销孔并进行耦合应力计算,与圆形销孔结构活塞对比可知,异型销孔结构可以大幅度降低销孔棱缘的应力集中,活塞的承载能力有所提高.利用活塞销孔疲劳试验机进行异型销孔活塞的疲劳试验,试验完成1.0×107个循环,活塞销孔表面接触良好,说明双侧圆锥形异型销孔的结构设计满足发动机可靠性要求.%For the piston of highly-intensified diesel engine, the relationship between mesh number and coupling stress conver gence at the piston pinhole edge was studied. Then the accurate calculation of coupling stress was carried out. The influence of non-circular pinhole structure on piston stress distribution was researched. According to the calculated results of coupling stress, the initial positions and angles of non-circular pinhole were determined, the conical non-circular pinholes on both sides were designed and the coupling stress was calculated. Compared with the circular pinhole structure, the non-circular pinhole structure decreased the stress concentration of pinhole edge, which improved the bearing loads of piston. On a test machine, the fatigue tests of pinhole were carried out. The L OX 107 cycles were completed and the contact surfaces of pinhole still worked well, which proved that the non-circular pinhole structure could meet the reliability requirement of diesel engine.
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