多少年来,制造飞机蒙皮零件用的拉型模一直沿用木材、水泥钢架、环氧胶砂结构,其主要缺点是重量太重,给使用、运输、保管、存放带来一系列的困难,同时又要用大量的上等红松和精质层板。近几年来,部属各有关单位大抓模胎轻化和以塑代木。 For many years, the drawing mold used to make aircraft skin parts has been using wood, cement steel frame and epoxy rubber sand structure. The main disadvantage is that the weight is too heavy, which brings a series of difficulties to use, transportation, storage and storage, At the same time with a large amount of fine red pine and quality laminates. In recent years, the various subordinate units pay close attention to die-casting and plastic-wood.