English unit

According to the situation that the PDS database is American English system,this paper makes a change it to metric system, and also provides detail methods for all data files related to English and metric system, that is piping materials class data files, piping specification data files, piping job specification database and p.

针对ＰＤＳ所携带的数据库是美国英制管件库这种情况，本文提出了ＰＤＳ数据库公制化设想，并且对与公英制有关的所有数据文件，即材料等级列表文件、管件种类列表文件、管件规范库和几何尺寸库提供了具体的实现方法。

Adopting special lantern gear to minify the drive error of the screw drive chain on CA6140 lathe,high-precision inch-system lead screw and modulus lead screw can be processed.

采用专用挂轮,减小了CA6140螺纹传动链的传动误差,可加工出高精度英制丝杠和模数丝杠。

Unification of cotton yarn count conversion factor between English count and tex system;

棉纱线英制支数与特克斯之间转换系数的统一