内浇道出流线速度的控制对减少球铁铸件二次渣的作用

Effects of Controlling Linear Speed of Inner Gate Outflow on Reducing Secondary Oxidation Slag of Nodular Iron Casting

介绍了内浇道出流的线速度的控制对球铁件二次氧化夹渣的作用。对在充型过程中因内浇道出流线速度较快而导致铁液发生紊流(飞溅、翻腾),对球铁件二次氧化夹渣的形成原因进行了分析。生产应用证明,控制内浇道出流线速度,采用内浇道相对开放的浇注系统及多点分散、底注的方式,对减少铁液紊流造成球铁件的二次渣非常有效。另外,对于生产高端球铁件,浇注系统辅以泡沫陶瓷过滤器,效果更好。建议内浇道出流的线速度应控制在30~60 cm/s或更低。

The effect of controlling over outflow line speed of the inner gate on secondary oxidation slag of nodular iron casting were introduced. The causes of the formation of secondary oxidative slag of the iron were analyzed by the turbulent flow（splash and rolling） of the molten iron during the process of filling the flow line in the filling process. Production application proves that controlling the line speed of the runner, and the runner relatively narrows the gating system,multi-point dispersion, bottom-injection mode is more dispersed, it is very effective to reduce the secondary slag of the ductile iron. In addition, for the production of high-quality ductile iron parts, pouring system with foam ceramic filter, the effect is better. The flow line velocity in runner advice that should be controlled in 30~60 cm/s or less.