球墨铸铁曲轴的铸造及热处理工艺

Foundry and Heat Treatment Technology of Ductile Iron Crankshafts

针对高性能球墨铸铁曲轴整体对开、平面分型工艺易出现夹砂、气孔等铸造缺陷的问题,重新设计了铸造工艺,采用曲面分型,配以凸凹模板,设计了无芯铸造曲轴分型工艺,简化了操作工序,避免了夹砂、气孔等铸造缺陷的产生,降低了生产成本。为使铸件组织均匀,研制出了曲轴自动连续冷却生产线以及悬挂式旋转风雾冷却装置,均匀冷却后工件的热应力和组织应力分布均匀,减少了工件变形,提高了曲轴的质量,改善了曲轴的性能,实现了多缸曲轴的批量稳定生产。

The scabs and the blowholes easily existed in ductile iron crankshaft castings by straight half parting.In order to solve the problems,we design new foundry technology that has no cores by curved parting and concave-convex mould board,which simplifies working procedures,avoids scabs and blowholes,and reduces costs.In order to get uniform microstructure,the technology and the equipments of normalizing treatment with suspended type rotating spray cooling were successfully developed,which made the heat stress and the structural stress of workpieces more uniform,reduced the deformation of workpieces,and improved crankshaft quality.Multi-cylinder crankshafts can be steadily produced.