重型拖车球铁连接器铸造工艺重型拖车球铁连接器铸造工艺

Casting Production Process of a Ductile Iron Coupler Used for Heavy Trailer

介绍大型拖车连接器球铁铸件的铸型工艺和熔炼工艺试验过程。实践表明,采用纯净度较高、w(Mn)量较低的生铁,适当提高w(Si终)量,采用二次孕育和随流孕育是确保铸态球铁获得高铁素体、高伸长率的关键措施。根据铸件具有大平面、壁厚薄而不均匀的特点,为确保铸件组织和性能均匀,采用多道内浇道分散进铁、同时凝固的基本工艺原则;在易生皮下气孔部位设置内浇道防止皮下气孔出现;在局部厚壁部位设置热冒口防止缩松缺陷。

The development process of the casting method and melting process of a ductile iron coupler used for heavy trailer was described.Test showed that adopting high purity and low-Mn Pig iron,properly enhancing final Si content,adopting twice ladle inoculation and stream inoculation are the key measures to obtain high ferrite content and high elongation.Considering that the casting has large flat surface and thin and uneven section thickness,an effective measure to ensure structure and properties uniformity of the casting is to adopt the casting method principle that the molten metal to be introduced into the casting cavity with multiple ingates from both sides of the casting to promote all parts of the casting solidifying simultaneously. In addition,setting ingetes at the locations prone to form pinhole is the effective method to prevent pinhole defect,and setting gated-through feeders at locations having heavy thickness and high shrinkage formation tendency is the effective method to prevent shrinkage defect.