真空密封造型(或称减压造型)是七十年代初国外出现的一种新的造型工艺。它和一般的造型方法相比,不同的地方在于用塑料膜包覆模型并密封砂箱,此外就是采用没有粘结剂的干砂作为造型材料,由于型砂的流动性很好,只要使密封的砂箱呈负压(400毫米汞柱)型砂就被充分压实。在造型设备中有一标准模板,模板正面有许多小孔与下面的空盒相 Vacuum seal modeling (or decompression modeling) is the early 70s appeared abroad a new modeling process. It is compared with the general modeling method, the difference lies in the plastic film coated model and sealed sand box, in addition is the use of binderless dry sand as a modeling material, because the flow of sand is very good, as long as the sealed Sandbox negative pressure (400 mm Hg) sand is fully compacted. There is a standard template in the styling equipment, with many small holes on the front of the form and empty boxes below