缸体油气道冷芯工艺研究

Research on Cold Core Making Process for Oil Gas Duct of Cylinder Block

缸体油气道腔要求壁厚均匀、表面光洁、不允许有断芯和脉纹等铸造缺陷。因此,油气道砂芯既要有足够的常温强度,以保证砂芯在起模、修芯和转运等过程不产生破损断裂,又要有良好的高温强度和热稳定性,以满足在浇注和凝固过程中砂芯变形量小、不断芯或不产生裂纹。研究了三种特种砂对冷芯砂常温和高温性能的影响,采用宝珠砂加入量40%~60%冷芯工艺生产的缸体油气道芯能够满足铸造过程质量要求。

The oil gas duct cavity of the cylinder block requires uniform wall thickness, smooth surface and no casting defects such as broken core and veining, Therefore, the oil gas duct sand core should not only have high room temperature strength, to ensure that core does not break and fracture during stripping, cleaning and transfering, but also have good high temperature strength and thermal stability, to ensure small deformation, none broken or crackle for core in pouring and solidification process. The effects of three kinds of special sands on performance of cold core sand at room temperature and high temperature were studied. Adopting cold core technology with 40% -60% addition of ceramsite, oil gas duct sand core production can meet the quality requirements of the casting process.