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Dosch - Venturi Tubes
Venturi tube according to ISO 5167 for precise flow measurement. When it comes to precisely measuring the flow of aggressive and non-aggressive gases, vapours and liquids, a Venturi tube is an excellent choice. Venturis enable minimal pressure losses at high mass flows. The short inlet and outlet sections are particularly advantageous for this type of differential pressure sensor. From the oil and gas industry to the chemical industry, especially petrochemicals, or even in power stations, our flow meter in accordance with ISO 5167 are used. Due to their precise and reliable measurement, a Venturi flow meter is generally very popular in plant engineering.
In addition to other flow meter, Dosch Messapparate specialises in the manufacture of Venturi tubes and focuses on professional design in accordance with the requirements of ISO 5167. For example, after redefining the range of applications for turned Venturi tubes up to 350 millimetres in diameter, we adapted them within a short space of time.
We offer you customised Venturis in various designs. We will advise you in detail in advance. Our team then manufactures the tubes according to your requirements. Any diameter and the use of special materials, such as nickel-based alloys and plastics, are possible.
Put your trust in Dosch, the experts for precise measuring solutions, professional advice and customised requirements.
- Customised: In accordance with ISO 5167, there are three versions of Venturi tubes, which we adapt specifically to your systems and requirements.
- Precise: Thanks to their precision in differential pressure measurement, Venturis ensure a long service life for the entire system.
- Flexible: A Venturi tube is suitable for many different media and can be manufactured in different diameters.
- Economical: The long-term accuracy and reliability of Dosch Venturi tubes lead to a reduction in operating costs and incorrect measurements.
Venturi meters consist of an inlet cylinder, an inlet cone, to which the cylindrical neck section (throttle opening) and the outlet cone are connected. They can be designed either as a weld-in Venturi tube for high pressures or as a flanged-in flow measurement tube. According to the ISO 5167 calculation standard, Venturi tubes are divided into three types depending on how their inner surfaces are manufactured:
These precision flow tubes are particularly relevant for smaller nominal diameters (DN 50 to DN 250). The higher roughness requirements necessitate mechanical processing of the inner surface of the inlet cone. Depending on the application, the measurement uncertainty is in the range of 1% – 3% of the flow coefficient.
Venturi tubes with a rough inlet cone welded from sheet steel
Venturi tubes with a rough inlet cone welded from sheet steel are used for larger nominal diameters (DN 200 to DN 1200). As the influence of the pipe’s inner surface is less pronounced with larger nominal diameters, a more cost-effective sheet metal construction can be used here. Depending on the application, the measurement uncertainty is in the range of 1.5% – 3% of the flow coefficient.
Venturi tubes with grey cast iron inlet cone
Venturi meters with a grey cast iron inner profile offer the lowest measurement uncertainties and are suitable for a medium nominal diameter range (DN 100 to DN 800). Due to the more complex manufacturing process, these are recommended for particularly high measurement requirements. Depending on the application, the measurement uncertainty is in the range of 0.7% – 2.5% of the flow coefficient.
We offer you the right products for Venturi tubes, such as pressure tapping nozzles
Pressure tapping nozzlesTypical versions of the pressure taps are
- Smooth nozzles for screw connections
- Welding nozzles
- Threaded nozzles
- Nozzles with flanges
Venturi tubes can be fitted with shut-off valves and/or valve blocks. Condensate traps are recommended for vapour applications.