铸造大中型箱体铸件,为了使起模成为可能,为了提高铸件的几何精度,多采用抽芯模。抽芯模主要包括三部分,模芯、燕尾和活块。一般抽芯模,这三部分均采用木质材料制作。使用木质材料、强度、刚度比较低,容易变形,遇温度、湿度有较大变化时,变形更甚,长为2m铸件,有时变形量超过10mm。木质燕尾、配合精度较低,更增大了变形量,木质 Casting large and medium-sized box castings, in order to make the mold as possible, in order to improve the geometric accuracy of the casting, the use of multi-core mode. Core withdraw core mainly consists of three parts, core, dovetail and live block. General core pulling mode, these three parts are made of wood materials. The use of wood materials, strength, stiffness is relatively low, easy to deformation, temperature, humidity greater changes, the deformation even worse, long 2m castings, sometimes more than 10mm deformation. Wood dovetail, with lower precision, but also increased the amount of deformation, wood