敞开式冲入法球化衰退的原因与防止措施

Reason and Prevent Measures of Degradated Spheroidization by Opened Conventional Method

介绍了采用敞开式冲入球化法处理工艺生产球墨铸铁件的生产情况及出现的球化衰退问题,通过对化学成分、出铁温度、球化处理包的情况等原因进行分析,提出了改进措施：制定严格的出铁温度执行标准,将出铁温度统一控制在1 490-1 510℃;对于距离较远的电炉,出铁后用珍珠岩覆盖,减少运输过程中的温度损失,并且减少Mg合金的氧化,从而提高铁液中的w（Mg残）量;设计新型筑包用包衬胎模,使包衬与堤坝实现一体化,增强堤坝的抗冲击强度,避免铁液过早与球化剂反应。生产结果显示,球化衰退的次数明显减少,部分月份球化衰退现象达到零,而且石墨的圆整度也有较大提升。

The situation of using open ladle poor-over nodularlizing process to produce nodular iron castings and possible nodularization degeneration problem was introduced. By analyzing the reason of chemical composition,tapping temperature and ball handling package and spheroidizing bag,the following improvement measures were raised. Strict implementation of standards were made. The tapping temperature was controlled by 1 490-1 510℃. Perlite covering was used on the iron melt by distant electric furnace to reduce temperature loss and Mg alloy oxygen during transport. That increased the amount of Mg in melt. A new kind of package die block was designed to make packing and embankment integration. That enhanced the impact strength of embankment and avoided reaction of molten iron and nodulizer too early. Production results showed that the degradated spheroidization significantly reduced. In some months, it reached zero. And the roundness of graphite also had a larger increase.