本文件规定了文丘里管[1]的几何形状和使用方法（安装和操作条件），当文丘里管[1]插入满管运行的导管中以确定在导管中流动的流体的流速时。 本文件还提供了计算流速的背景信息，并与ISO 5167-1中给出的要求一起适用。 本文件仅适用于文丘里管，其中的流动在整个测量部分保持亚音速，并且流体可以被认为是单相的。此外，文丘里管只能在未根据本标准校准的管道尺寸、粗糙度、直径比和雷诺数的规定限制内使用，或者它们可以在其校准范围内使用。本文件不适用于脉动流的测量。它不包括在尺寸小于50的管道中使用未经校准的文丘里管？mm还是大于1？200？嗯，或者管道雷诺数低于2的地方？×？105. 本文档涉及三种类型的经典文丘里管: a)“铸态”； b)机加工； c)制造的(也称为“粗焊铁皮”)。 文丘里管由连接到圆柱形喉部的会聚入口组成，所述圆柱形喉部又连接到称为发散部分(或替代地扩散器)的锥形膨胀部分。文丘里喷嘴（和其他喷嘴）在ISO中处理？5167-3. 笔记？在美国，经典的文丘里管有时被称为赫歇尔文丘里管。 ？ [1]？在美国，经典的文丘里管有时被称为赫歇尔文丘里管。

This document specifies the geometry and method of use (installation and operating conditions) of Venturi tubes[1] when they are inserted in a conduit running full to determine the flow rate of the fluid flowing in the conduit. This document also provides background information for calculating the flow rate and is applicable in conjunction with the requirements given in ISO 5167-1. This document is applicable only to Venturi tubes in which the flow remains subsonic throughout the measuring section and where the fluid can be considered as single-phase. In addition, Venturi tubes can only be used uncalibrated in accordance with this standard within specified limits of pipe size, roughness, diameter ratio and Reynolds number, or alternatively they can be used across their calibrated range. This document is not applicable to the measurement of pulsating flow. It does not cover the use of uncalibrated Venturi tubes in pipes sized less than 50？mm or more than 1？200？mm, or where the pipe Reynolds numbers are below 2？×？10⁵. This document deals with the three types of classical Venturi tubes: a) “as cast”; b) machined; c) fabricated (also known as “rough-welded sheet-iron”). A Venturi tube consists of a convergent inlet connected to a cylindrical throat which is in turn connected to a conical expanding section called the divergent section (or alternatively the diffuser). Venturi nozzles (and other nozzles) are dealt with in ISO？5167-3. NOTE？In the USA the classical Venturi tube is sometimes called the Herschel Venturi tube. ？ [1]？In the USA the classical Venturi tube is sometimes called the Herschel Venturi tube.