曲轴加工的迭代定心法研究

Research on Iterative Centering Method of Crankshaft Machining

曲轴生产过程中,两端中心钻孔是曲轴后续加工的定位基准,它的定位精度对曲轴成品件的动平衡影响较大。目前,曲轴中心钻孔通常采用几何定心法或质量定心法,该类方法定位精度有限,成品件仍有较大动不平衡量。首先基于逆向工程,提出了虚拟加工方法,得到实际锻件的虚拟加工成品件;其次,根据微分切片的思想及动平衡双面校正原理,编制了曲轴动平衡的计算软件;同时,在推导出的曲轴迭代定心公式基础之上,开发了曲轴迭代定心软件;最后,利用广西某企业生产的4T18型号曲轴来验证前述方法及软件的正确性。实验结果表明:相比传统定心方法,按照曲轴迭代定心软件计算偏心量加工的曲轴动不平衡量可降低60%,大大降低因动不平衡而导致的曲轴废品率,为实际生产中曲轴定心提供了一种快速可靠的方法。

In the shaft production process, the central drilling at both ends is the positioning reference for the subsequent machining of the crankshaft, and its positioning accuracy has a great influence on the dynamic balance of the finished crankshaft parts. At present, the center hole of the crankshaft usually adopts the geometric centering method or the mass centering method. The positioning accuracy of this method is limited, and the finished parts still have a large dynamic unbalance. Firstly, based on reverse engineering, this paper proposes a virtual machining method to obtain the virtual finished parts of the actual forgings. Secondly, according to the idea of differential slicing and the principle of double-balance correction of dynamic balance, the calculation software of the dynamic balance of the crankshaft is compiled. At the same time, it is derived. Based on the crankshaft iterative centering formula, the crankshaft iterative centering software was developed. Finally, the 4T18 model crankshaft produced by a certain company in Guangxi was used to verify the correctness of the above method and software. The experimental results show that compared with the traditional centering method, the crankshaft dynamic unbalance calculated by the crankshaft iterative centering software can reduce the dynamic imbalance of the crankshaft by 60%, greatly reducing the crankshaft scrap rate caused by the dynamic imbalance, and setting the crankshaft for actual production. The heart provides a fast and reliable method.