对4DA1柴油机缸体砂眼缺陷的产生原因进行了分析,发现芯撑表面的涂料以及芯撑与水套芯交接处大量堆积的涂料在铁液与芯撑熔合时,在高温铁液的作用下,耐高温的涂料会从熔化了的芯撑上脱落下来,并随铁液分散于型腔各处,凝固后形成砂眼缺陷。针对于此,提出了整改组芯工艺,使芯撑不沾上涂料,并在下芯时严格控制散砂。改进后缸体的上表面缺陷以及机加工缸筒砂眼已经得到了有效地控制,缸筒砂眼发生率由原来的20%降到3%以下。 The causes of the 4DA1 diesel engine cylinder trachoma defect were analyzed. It was found that when the coating of the core support surface and the core pile and the water core junction accumulate a large amount of coating, when the molten iron and the core support are fused, under the action of high temperature molten iron, High-temperature coatings will melt off from the core support off, and with the dispersion of molten iron throughout the cavity, the formation of trachoma defects. In response to this, proposed rectification group core technology, so that the core support is not stained with paint, sand and sand in the core under strict control. Improved surface defects of the cylinder block as well as machined cylinder bore have been effectively controlled, and the incidence of cylinder blisters has been reduced from 20% to less than 3%.