柴油机主轴承孔胀断工艺试验与模拟研究
Simulation and Technological Experiment of Main Bearing Hole Splitting for Diesel Engine

针对柴油机主轴承孔圆度问题，在装配完成、温度为150 ℃和施加爆压3种状况下，对原机模型和胀断模型的主轴承孔位移进行数值模拟，分析了两种模型主轴孔周围位移的差异；制造出RuT450和HT250材料的试验件，运用试验对比方法，从材料材质、胀断面质量和主轴承孔径变化方面，对Ru450、HT250试验件和德国MAN公司的D26合金材料进行主轴承孔胀断工艺研究。结果表明Ru450在硬度和强度方面都能满足柴油机性能要求，且适合采用胀断技术。胀断后Ru450试样胀断面非常光整且材质组织非常致密，对主轴承孔径进行检测，发现所有样件孔径变化都不超过设定值0.1 mm，表明胀断后主轴承孔加工精度较高。
On diesel engine main bearing hole roundness, the displacement of main bearing hole via original model and splitting model are simulated when it is assembled, at 150℃ and under explosion pressure. The stress difference around the main bearing hole is analyzed. With contrast test analysis, RuT450 materials and HT250 materials were used respectively to create specimen. With the comparison method, the influence of the material quality, the splitting surface quality and the change of main bearing hole precision on the fracture splitting technology of the main bearing hole among the Ru450, the HT250 specimen and the German company MAN D26 alloy material was studied. The results show that Ru450 can meet the performance requirements of hardness and strength for the diesel engine, and it is suitable for the use of splitting technology. The splitting surface of Ru450 specimen is very smooth and the material organization is very compact. The change in all main bearing hole detected in specimens does not exceed the setting value of 0.1 mm. It shows that the precision of the expanding hole after splitting is very high