运用大孔出流理论设计滚筒铸铁件顶雨淋浇注系统

Design of Shower Gate System of Roller Casting Using Large Orifice Discharge Theory

梳棉机用锡林滚筒,材质HT200,轮廓尺寸φ1 318 mm×1 150 mm,壁厚22 mm,铸件重1260 kg,表干砂型。内外表面加工。为了防止铸造缺陷,运用大孔出流理论设计顶雨淋浇注系统;用收缩模数法校核浇注系统当冒口的补缩能力。设计结果:1只直浇道φ70 mm,圆环形横浇道截面50/60 mm×50 mm。批量生产表明:铸件没有气孔,夹渣及缩孔等缺陷,工艺出品率94%。实践证明:采用大孔出流理论设计浇注系统,收缩模数法校核其补缩能力,实现浇注系统当冒口的工艺是可靠的。

The cylinder roller used for carding machine is made of HT200. The dimensional size, wall thickness and total weight of the casting are 1 318 mm × 1 150 mm, 22 mm and 1 260 kg respectively. The casting is made utilizing surface dry sand mold. The internal and external surface of the casting is machined. In order to prevent casting defects, shower gate system of roller casting was designed using large orifice discharge theory, and the feeding ability of gating system which was also used as riser is verified by modulus calculation method. The designed results are that the diameter of the sprue is 70 mm; the transverse section size of the cirque runner is 50 mm/60 mm × 50 mm, and the size of thirty-two ingates is φ12 mm × 50 mm. The batch production shows that there are no blowhole, inclusion and shrinkage cavity, and the overall yield of casting is 94%. The production indicates that the technology of using the large orifice discharge theory to design gating system and using modulus calculation method to verify its feeding ability is reliable to use gating system as riser.