由一次型获得的铸件精度主要取决于铸型的刚度,亦即取决于铸型在金属液热力作用下,阻止其型壁位移的能力。对于湿型,此种性能通常与型砂的紧实度有关;对于硬化砂型,则与型砂硬化后的强度有关。近十年来,就传统的加热烘干硬化方法而言,增添了许多新方法:各种化学硬化法、冷冻法和真空覆膜法等。因此、有必要再来谈谈关于湿粘土砂型的使用范围问题。 The accuracy of castings obtained from one-shot depends mainly on the stiffness of the mold, ie, the ability of the mold to stop its wall displacement under the thermal effect of the molten metal. For wet type, this property is usually related to the compaction of the sand; for hardened sand, it is related to the strength of the hardened sand. In the last ten years, many new methods have been added for the traditional heating and drying hardening method: various chemical hardening methods, freezing methods and vacuum coating methods. Therefore, it is necessary to talk about the use of wet clay sand type problems.