汽车前桥的V法铸造工艺

The V-casting Process of Front Bridge of Automobile

介绍了汽车前桥的铸件结构和技术要求,详细阐述了该铸件的生产条件和铸造工艺：利用V法造型机造型,砂箱尺寸2 500 mm×1 800 mm×350/300 mm;采用开放式浇注系统,浇口比为ΣF直：ΣF横：ΣF内=1：1.75：7,最小截面积为9.6 cm2,冒口尺寸为φ80 mm;在砂箱的箱档上焊接支撑与吸气2个功能的支撑钢管,涂刷涂料前,对砂型表面的涂料进行烘干,造型时要保证型腔干净,防止中间披缝;浇注温度1 540~1 560℃,浇注时间25~30 s;保压15 min,保温缓冷1 h后开箱,浇注与造型过程真空度≥55 kPa。最终生产的铸件的表面粗糙度比树脂砂工艺生产的铸件高1~2级。

The casting structure and technical requirements of front bridge of automobile was introduced. The production conditions and casting process was elaborated. The molding was processed by a V-molding machine. The size of sand box is 2 500mm×1 800 mm×350/300 mm. An unchoked running system was used. Its gating ratio was ΣFpouring：ΣFrunner：ΣFflow=1：1.75：7. The minimum cross section area was 9.6 cm2 and the diameter of riser was φ80 mm. Two steel pipes were welded on the sand box to sustain the structure and ventilate the inside. Before painting,the sand mold surface coating was dried and cavity was kept clean in the molding to prevent the joint flash. The pouring temperature was 1 540~1 560 ℃ and casting time was 25~30 s. Pressure was kept for 15 min and cooled in the next hour. The vacuum level in casting and molding was 55 kPa or above. The surface roughness of final production was improved by 1~2 grade than that made by resin sand casting.