本文件规定了法兰管道系统中用作隔离阀和止回阀的闸阀、截止阀、隔膜阀、球阀、旋塞阀、蝶阀设计类型的双向金属阀的基本面对面（FTF）和中心对面（CTF）尺寸系列。每个基本系列的面对面和中心对面尺寸可根据需要与符合等效EN或ASME法兰系列的配对尺寸的法兰一起使用。购买本文件时可获得的所有当前修订均包含在购买本文件中。

This document specifies the basic series of face-to-face (FTF) and centre-to-face (CTF) dimensions for two-way metal valves of the gate, globe, diaphragm, ball, plug, butterfly design types used as isolating and check valves in flanged pipe systems. Each basic series of face-to-face and centre-to-face dimensions can be used as required with flanges of mating dimensions conforming to the equivalent EN or ASME flange series.All current amendments available at time of purchase are included with the purchase of this document.