采用高炉铁液生产大高径比灰铸铁钢锭模

介绍了大高径比钢锭模的铸件结构及技术要求,详细阐述了生产该铸件的铸造工艺:采用横做横浇工艺,封闭式浇注系统,浇口比为ΣF直:ΣF横:ΣF内=1.4:1.2:(1.1~1.0),选用尺寸为φ50 mm的出气冒口;呋喃树脂砂造型,将球铁芯骨固定在芯盒内,砂层厚度为40~50 mm;大高径比钢锭模采用高炉铁液浇注,出铁温度控制在1 400±20℃,在出铁过程中,向流铁槽内加入粒度为3~6 mm的75SiFe及65MnFe,加入量分别为0.3%~0.5%、0.5%~1.0%,铁液最终成分为w(C)4.1%~4.6%、w(Si)0.6%~1.0%、w(Mn)0.7%~1.0%、w(P)≤0.10%、w(S)≤0.03%;浇注前扒渣3~5次,浇注温度控制在1 260~1 300℃,浇注速度2~3 t/min。最终生产的铸件内壁平直度公差为3~5 mm,内壁光滑,抗拉强度也符合技术要求。

Using Blast Furnace Iron Melt to Produce Gray Iron Ingot Mold with Big Height/Diameter Ratio

The configuration and technical requirements of a ingot mold casting with big height/diameter ratio was introduced.Casting method of the ingot was described in detail：adopting horizontal molding method and horizontal pouring process;using pressured gating system with section ratio as ∑Fsprue：∑Fruner：∑Fingates=1.4：1.2：（1.1 ～1.0）;using venting riser with diameter of 50 mm;using furan resin sand for molding;the core iron made of nodular iron was fixed in the core box,the thickness of core sand lyer was of 40～50 mm;the ingot mold was poured by using iron melt from a blast furnace;the tapping temperature was controlled in the range of 1 420＋20 ℃ ;0.3%～0.5% 75SiFe with grain size of 3～6 mm and 0.5%～1.0% 65MnFe with size of 3～6 mm was added into the tapping lauder during the tapping process; the final composition was as follows：w （C） 4.1%～4.6%,w （Si） 0.6% ～1.0%,w（Mn） 0.7%～1.0%,w（P）≤0.10%,w（S） ≤0.03%;slag skimming was conducted 3～5 time;pouring temperature was controlled in the range of 1 260～1 300 ℃ ;pouring rate was controlled in the range of 2～3 t/min;the inner wall planeness and straightness tolerance of the finally produced castings was of 3～5 mm,the inner wall was smooth and the tensile strength also met the technical requirement.