ISO 5167-1:1991/Amd 1:1998
用压差装置测量流体流量.第1部分:圆截面管道中插入的节流孔板、喷嘴和文杜利管.第1次修订
Measurement of fluid flow by means of pressure differential devices - Part 1: Orifice plates, nozzles and Venturi tubes inserted in circular cross-section conduits running full; Amendment 1