论文部分内容阅读
如果球铁件的关键模数小于2.5厘米,不加冒口是难以获得致密铸件的。本文首先简介了球铁凝固时体积的变化规律,由于球铁有二次收缩现象,故采用传统的冒口技术难以获得无内部缩松的铸件。文中举例说明球铁控制压力冒口的设计过程,介绍了设计时需用的图表。采用控制压力冒口技术一是可以保证球铁和蠕铁铸件内部致密键全;其次可以提高铸件工艺出品率,节约原材料、能源、取得良好经济效益。
If the ductile iron key modulus is less than 2.5 cm, without risking it is difficult to obtain a dense castings. In this paper, the change rule of the volume of the iron-iron during solidification is introduced. Because of the secondary shrinkage of the ductile iron, it is difficult to obtain the castings without internal shrinkage by the traditional riser technology. The article illustrates the design process of ductile iron pipe with pressure riser and introduces the chart required when designing. Adopting the control pressure riser technology can ensure that the internal dense nodules of the ductile iron and the vermicular iron castings are all available; secondly, the production rate of the castings can be raised, the raw materials and energy can be saved, and good economic benefits have been achieved.