生产中大型铸件多采用手工造型,生产率低,质量较差、劳动强度大。虽然抛砂和震击紧实法在部分中大件造型中得到应用,但抛砂机结构较复杂、操作不够灵活,并多局限于粘土砂造型上;震击造型机结杂庞大,应用受到限制,已满足不了新的要求。自硬砂的发展为中大件造型创造了良好条件,尤其冷硬树脂砂得到更为广泛的应用。许多厂家已用冷硬树脂砂生产多种类型的铸件,但尚无很适合中大件冷 Large-scale production of castings used in hand modeling, low productivity, poor quality, labor-intensive. Although the method of sand throwing and shock compacting is applied in some large and medium-sized pieces, the structure of the sand throwing machine is complicated and the operation is not flexible enough, and is mostly confined to the shape of clay sand. The shock shaping machine knit is huge and the application is affected Restrictions, can not meet the new requirements. The development of self-hardening sand has created good conditions for medium and large-sized shapes, especially the chilled resin sand has been widely used. Many manufacturers have used chilled resin sand to produce many types of castings, but not yet suitable for medium to large cold