ISO 5167-4 specifies the geometry and method of use (installation and operating conditions) of Venturi tubes when they are inserted in a conduit running full to determine the flowrate of the fluid flowing in the conduit.
This standard also provides background information for calculating the flowrate and is applicable in conjunction with the requirements given in ISO 5167-1.
Venturi tubes are used for flow measurement in various industrial applications. They are differential pressure devices that operate based on the principle of pressure difference created between the upstream and throat sections of the Venturi tube. By measuring this pressure difference, the flowrate of the fluid can be accurately determined.
ISO 5167-4 ensures that Venturi tubes are designed and installed correctly to achieve accurate flow measurement results. It covers different types of Venturi tubes and specifies their dimensions and installation requirements.
ISO 5167-4 PDF Download
Like other parts of the ISO 5167 series, ISO 5167-4 is essential for maintaining accuracy and consistency in flow measurement, which is crucial for various industrial processes and applications. It helps ensure that Venturi tubes are used effectively and reliably to determine fluid flowrates in a wide range of scenarios.
Venturi tubes
This article explains about Measurement of fluid flow by means of Venturi tubes of pressure differential devices inserted in circular cross-section conduits running full.
ISO 5167-4 defines the specifications and usage guidelines for Venturi tubes, which are devices used to measure fluid flow rates in pipes. The standard covers three types of classical Venturi tubes: cast, machined, and rough welded sheet-iron.
These Venturi tubes consist of a convergent inlet, a cylindrical throat, and a conical expanding section called the “divergent.” The standard ensures that the tubes are used correctly and installed properly to accurately measure flow rates.
ISO 5167-4 is applicable for flow measurements where the fluid remains subsonic throughout the measuring section and is single-phase. It specifies limitations for pipe size, roughness, diameter ratio, and Reynolds number for accurate measurements.
Please note that the standard does not apply to pulsating flow measurements or Venturi tubes used in pipes smaller than 50 mm or larger than 1,200 mm, with pipe Reynolds numbers below 2 x 10^5.
For high-pressure gas applications, additional research and calibration might be required to achieve optimal accuracy. The standard also provides information on the Herschel Venturi tube, a term used in the USA for classical Venturi tubes.
Read Also:
- ISO 5167-1 Download PDF – Measurement of fluid flow by means of pressure differential devices Part 1
- ISO 5167-2 Download PDF – Orifice plates
- ISO 5167-3 PDF Download – Nozzles and Venturi nozzles
- ISO 5167-5 PDF Download – Cone meters
- ISO 5167-6 PDF Download – Wedge meters
FAQs:
ISO 5167-4 is a standard that specifies the geometry and usage guidelines for Venturi tubes when measuring fluid flow rates in pipes. It covers three types of classical Venturi tubes: cast, machined, and rough welded sheet-iron.
Venturi tubes consist of a convergent inlet, a cylindrical throat, and a conical expanding section called the “divergent.” The design ensures accurate measurement of fluid flow rates.
The standard ensures that Venturi tubes are installed correctly and used in appropriate operating conditions to maintain accuracy. It sets limitations for pipe size, roughness, diameter ratio, and Reynolds number.
The standard is applicable only to flow measurements where the fluid remains subsonic throughout the measuring section and is considered single-phase. It is not suitable for pulsating flow measurements or for pipe sizes smaller than 50 mm or larger than 1,200 mm, with pipe Reynolds numbers below 2 x 10^5.
For high-pressure gas applications, research is ongoing (see References [1], [2], [3] in the Bibliography of ISO 5167-4). Calibration over the required flowrate range is recommended for optimum accuracy. Single or limited pressure tappings in each plane may be used in such cases.