用覆砂铁型铸造工艺生产球铁轮毂

介绍了用于QT450-10轮毂铸件的覆砂铁型铸造工艺:覆砂层厚度控制在7～10 mm,铁型壁厚20～30 mm;采用双工位覆砂造型机造型,模具温度控制在240±10℃;铸件采用边冒口补缩,浇注温度控制在1 420～1 350℃。生产结果显示:轮毂铸件表面粗糙度达到Ra12.5μm,尺寸公差等级CT7～8,工艺出品率88%,球化等级1～2级,石墨球大小6～7级,内部组织致密,产品合格率在95%以上。

Production of Nodular Iron Wheel Hub by Using Sand-Faced Metal Mould Casting Process

The sand-faced metal mould casting process used for production of QT450-10 grade nodular iron wheel hub was introduced： thickness of the facing sand layer was controlled in the range of 7-10 mm, the thickness of the cast iron mould in the range of 20-30 mm; a double-position sand-facing moulding machine was used to make the sand-faced metal mould, temperature of the pattern and metal mould was controlled in the range of 240±10 ℃ ;side risers were used to feed the castings, and the pouring temperature was controlled in the range of 1 420-1 350 ℃. The production result showed that the roughness of the wheel hub casting reached Ra12.5 μm, its dimensional accuracy reached grades of CT7-8, the casting yield rate reached 88%, nodularity of 1-2 class （Chinese standard）, graphite size of 6-7 class; the casting structure was dense and the casting pass rate was higher than 95%.