为节约原材料,降低生产成本,我厂于1976年3月进行了旧砂回用的生产试验。具体办法是:将振动落砂落下的干旧砂,经过双层机械振动筛,去掉块状和粉状物,然后掺入新砂中使用,作外型和大型芯用。经过试验,铸 In order to save raw materials, reduce production costs, I plant in March 1976 for the production of used sand back to the test. The specific approach is: the sand will fall off the vibration of sand falling sand, after double mechanical shaker, remove the lumps and powder, and then mixed with new sand used for exterior and large core use. After testing, cast