一、质量问题的提出制造机具毛坯中,铸造毛坯的重量最大,种类也最多。约占毛坯工业产值的60％。在工业发达国家,铸件一般占钢产量的10～20％,我国生产铸件与钢产量的比例,也在这个范围之内。铸造的生产过程复杂,从原材料进厂到铸件出厂,要经过砂处理、造型、熔炼、浇注、清理等各种工序,其中很多是不易控制的,这是一个特点。铸件生产过程的内在问题也很 First, the quality of the proposed manufacturing machinery blank, casting the largest weight of the rough, the most types. Accounting for about 60% of rough industrial output. In industrialized countries, castings generally account for 10% to 20% of steel output. The proportion of China’s production of castings and steel output is also within this range. Casting the production process is complex, from raw materials into the plant to the casting factory, to go through the sand treatment, modeling, melting, pouring, cleaning and other processes, many of which are not easy to control, which is a feature. Casting process is also inherent problems