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Annubar Flow element Pitot Tubes Flowmeter

The Pitot tube flowmeter is a double layered hollow manifold tube bent at a right angle, with multiple pressure tapping holes, capable of measuring both total fluid pressure and static pressure simultaneously. Used in conjunction with differential pressure transmitters and flow display devices. It is widely used in the production processes of industries such as petrochemicals, metallurgy, power plants, electricity, and textiles to measure the flow rate of fluids such as gases, liquids, steam, water, and air volume.

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Throttling device

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DESCRIPTION

Working Principle: A pitot tube is a double-layer hollow composite tube bent at a right angle, with multiple pressure-sensing holes that can measure both the total pressure and static pressure of the fluid simultaneously. A small hole is drilled at the head of the pitot tube in the direction facing the fluid flow, known as the total pressure hole. At this point, a "stagnation point" is formed where the fluid velocity is zero and the pressure is the total pressure. A number of static pressure holes, perpendicular to the fluid flow direction, are drilled at a certain distance from the head. The static pressure measured by each static pressure hole is equalized in a pressure equalization chamber before being output. Since there is a definite numerical relationship between the difference between the total pressure and static pressure of the fluid and the measured fluid velocity, the pitot tube can be used to measure the fluid velocity. Then, by combining this with the cross-sectional area of the pipeline, the magnitude of the measured flow rate can be calculated.
Parameter Performance:
- Accuracy: The accuracy of pitot tubes varies by brand and model. For example, the accuracy of WIKA's FloTec pitot tube is ≤±2% of the actual flow rate.
- Measurement Repeatability: The measurement repeatability of WIKA's FloTec pitot tube is 0.1%.
- Pressure Loss: Compared with other primary flow elements, WIKA's FloTec pitot tube has a smaller pressure loss, approximately <1%.
- Measurement Range: It is suitable for measuring single-phase fluids that completely fill the cross-section of the pipeline. The nominal size range is generally 50-1800mm (2"-72").
- Operating Temperature and Pressure: Under normal circumstances, the fluid temperature that the pitot tube can withstand is ≤450℃. In terms of operating pressure, the non-retractable type can withstand ≤20MPa, and the retractable type of average velocity tube can withstand ≤10MPa.
- Material: It is usually made of AISI 316 stainless steel. Other materials, such as 304 stainless steel and titanium alloy, can also be provided according to user requirements.