大直径曲轴自由锻成形工艺探讨

曲轴是各种内燃机中不可缺少的关键部件,它的寿命常常代表该内燃机的使用寿命。单纯从成形的角度考虑,用铸造的方法生产曲轴毛坯是最容易不过的事情。但由于铸造是一个金属冶炼且在砂型中凝固的过程,难以避免会出现夹渣、气空、白点等铸造缺陷而无法满足性能要求。工业上多采用各种压力加工方法来生产曲轴毛坯。小型内燃机上使用的尺寸和重量不大的曲轴一般采用模锻来大批量生产,尺寸较大特别是很大尺寸的曲轴就必需用其它的压力加工方法了。这里仅对特大尺寸的曲轴的自由锻成形工艺进行一些探讨。

Free Forging Forming Technology of Large Diameter of the Crankshaft

The crankshaft is the key component of the essential part of various internal com-bustion engines .Its life often represents the service life of internal combustion engine .If on-ly considering forming methord ,casting is the easiest .But because casting is a metal smel-ting and solidification in the moulding flask ,it is hard to avoid casting defects such as slag , air ,white and can not meet the property requirement .Various pressure processing methods are widely used in industry to produce crankshaft blank .The crankshaft used for small inter-nal combustion engine is usually small in size and light in weight ,and forging method is gen-erally used for its mass production ,but the larger size must be produced by using other pres-sure processing methods . T he free forging forming process for very large crankshaft dis-cussed in this essay .