论文部分内容阅读
我厂生产的纺机中梁是细长类铸件(见图),中间薄、边缘厚,铸件冷却过程中,薄部位先冷却并阻碍厚部位收缩而受压,厚部分后冷却收缩受阻碍而受拉,这样铸件极易产生变形。过去,我们在生产该件时,工艺上往往将型砂紧实度控制在80以上,浇注后4h打箱,但浇出的铸件绝大部分因变形量不合要求而报废。为改变这一状况,我们根据铸件结构、壁厚的特点,进行了工艺性试验。首先,在造型时将型砂紧实度
In our factory, the middle beam of smelter is a slender cast (see picture). The middle is thin and the edge is thick. During the cooling process of the castings, the thin parts cool first and block the contraction and compression of thick parts. Tension, so castings easily deformed. In the past, when we produced this piece, we often controlled the compaction degree of molding sand above 80, 4 hours after pouring, but most castings cast out were scrapped because of the unqualified requirements. In order to change this situation, we have carried on the technological test according to the casting structure, the characteristic of the wall thickness. First of all, the molding sand compactness