progressive dies短语¹⁴⁴⁹⁷²⁺² 基本例句 模具 Because there are lots of standard parts in a progressive die, it is very important to provide a convenient standard parts library for the CAD of progressive dies. 多工位级进模中包括大量的标准件,因而级进模 CAD 系统开发过程中必须建立具备良好实用性的标准件库。 chemyq