主轴承盖铸件的无冒口铸造工艺

Feederless Casting Process of the Main Bearing Cap Casting

球墨铸铁在形成过程中具有明显的石墨化膨胀,可以有效地抵消铁水在液态收缩、凝固收缩过程中的收缩量,如果石墨化膨胀的体积大于铁水在液态收缩、凝固收缩的体积之和,就有实现无冒口铸造的可能性。文中涉及的两种型号的主轴承盖均采用了无冒口铸造工艺,此两种型号的主轴承盖,虽然螺栓孔处的加工方式不同、浇注位置不同,但结构类似、单重相近,最终都实现了无冒口铸造。

Nodular cast iron has obvious graphitizing expansion in the forming process.It can effectively offset the amount of contraction of molten iron in the liquid and solidification shrinkage.If the volume of graphitizing expansion is greater than the sum of the volume of molten iron contraction in the liquid and solidification shrinkage,the feederless casting process is possible.The two main bearing caps with similar structure and single weight in this paper both adopted feederless casting process.