工业过程控制阀.第5部分:标记

[中文适用范围]： 规定控制阀的强制性和补充标记。一些强制性标记可能不适用于某些特殊设计的阀门，而一些补充标记可能仅适用于特定类型的控制阀。值得推荐 [外文原描述]： specifies mandatory and supplementary markings of control valves. Some mandatory markings may be inappropriate for some valves of special design, and some supplementary markings may be appropriate only to specific types of control valves. It is recommended that the marking of all valves conform to this standard whenever possible unless otherwise agreed between the manufacturer and purchaser.