铸钢“七○”砂,自七○年在全国范围和我省全面推广使用以来,在提高铸件质量,改善劳动条件,消除矽尘危害,以及废砂的综合利用等方面起了重要的作用;在造型材料的历史上曾引起了一场革命。当时从国务院到各省市曾予以高度的重视。七五年以来,我省工办和机械局曾多次组织到外地 Cast steel “70′′ sand has played an important role in improving the quality of castings, improving working conditions, eliminating dust hazards, and comprehensive utilization of waste sand since it was widely used throughout the country and in our province in the year of 970. In the history of modeling materials, it caused a revolution. At that time, a high degree of attention was paid from the State Council to all provinces and cities. Since 1975, the provincial bureau of engineering and machinery has organized many trips to the field.