本文件规定了喷嘴和文丘里喷嘴插入满管时的几何形状和使用方法（安装和操作条件），以确定管道中流动流体的流速。 本文件还提供了计算流量的背景信息，并适用于ISO 5167-1中给出的要求。 本文件适用于喷嘴和文丘里管喷嘴，在这些喷嘴和文丘里管喷嘴中，流量在整个测量段内保持亚音速，并且可以将流体视为单一流体- 阶段此外，每个装置只能在管道尺寸和雷诺数的规定限制内使用。它不适用于脉动流的测量。它不包括在管道尺寸小于50 mm或大于630 mm，或管道雷诺数低于10000的情况下使用喷嘴和文丘里喷嘴。 本文件涉及 a） 三种标准喷嘴: ISA 1932[1]喷嘴； 长半径喷嘴[2]； 喉部螺纹喷嘴 b） 文丘里管喷嘴。 这三种标准喷嘴在本质上是不同的，在本文件中分别进行了描述。 文丘里管喷嘴具有与ISA 1932喷嘴相同的上游面，但具有发散截面，因此，下游取压口的位置不同，单独描述。这种设计比类似的喷嘴具有更低的压力损失。对于所有这些喷嘴和文丘里管喷嘴，已经进行了直接校准实验，其数量、扩散和质量足以使相干应用系统基于其结果和系数，并具有某些可预测的不确定性极限。 [1] ISA是国家标准化协会国际联合会的缩写，该联合会于1946年被ISO取代。 [2] 长半径喷嘴与ISA 1932喷嘴的形状和测压口位置不同。

This document specifies the geometry and method of use (installation and operating conditions) of nozzles and Venturi nozzles when they are inserted in a conduit running full to determine the flowrate of the fluid flowing in the conduit. This document also provides background information for calculating the flowrate and is applicable in conjunction with the requirements given in ISO 5167‑1. This document is applicable to nozzles and Venturi nozzles in which the flow remains subsonic throughout the measuring section and where the fluid can be considered as single-phase. In addition, each of the devices can only be used within specified limits of pipe size and Reynolds number. It is not applicable to the measurement of pulsating flow. It does not cover the use of nozzles and Venturi nozzles in pipe sizes less than 50 mm or more than 630 mm, or where the pipe Reynolds numbers are below 10 000. This document deals with a) three types of standard nozzles: 1)    ISA 1932[1] nozzle; 2)    the long radius nozzle[2]; 3)    the throat-tapped nozzle b) the Venturi nozzle. The three types of standard nozzle are fundamentally different and are described separately in this document. The Venturi nozzle has the same upstream face as the ISA 1932 nozzle, but has a divergent section and, therefore, a different location for the downstream pressure tappings, and is described separately. This design has a lower pressure loss than a similar nozzle. For all of these nozzles and for the Venturi nozzle direct calibration experiments have been made, sufficient in number, spread and quality to enable coherent systems of application to be based on their results and coefficients to be given with certain predictable limits of uncertainty.   [1]   ISA is the abbreviation for the International Federation of the National Standardizing Associations, which was superseded by ISO in 1946. [2] The long radius nozzle differs from the ISA 1932 nozzle in shape and in the position of the pressure tappings.