In many industrial sectors such as power, metallurgy, chemical, and mining, air supply and induced draft ducts or other types of air volume ducts paired with boilers are widely used. Usually, duct cross-sections are both circular and square or rectangular, with very large areas and very short straight pipe sections. Control of flow size in ducts directly affects device efficiency, effectiveness, work quality, and safety performance. For duct characteristics, more mature large duct air measurement devices include averaging pitot tubes, wing-type, dual-throat tubes, etc. Most are based on dynamic pressure principle, with advantages of low pressure loss, low energy consumption, convenient installation, and low straight pipe length requirements.
Features
1 Accuracy and Repeatability
The positive pressure tap is taken on the pipe wall upstream of the cone, with tapping position selected in the uniform velocity region of ideal fluid, resulting in stable positive pressure signal; the negative pressure tap is located at the center of the cone tail, exactly in the region of minimum downstream pressure. Due to the centrally symmetric structure of the cone, the flow field in the cone tail center region is relatively static, and after throttling, only high-frequency low-amplitude small vortices appear in the negative pressure zone, making negative pressure signal fluctuation very small, thus outputting stable differential pressure signal with high metering accuracy and good repeatability.
2 Turndown Ratio and Pressure Loss
Turndown ratio 10:1, low pressure loss.
3 Self-cleaning function, suitable for dirty fluid flow measurement
Thorough sweeping design of the cone body avoids retention of residues, condensates, and particles in the fluid.
4 Scaled differential pressure value
Large scaled differential pressure with flexible selection. In low-velocity applications such as power plant air measurement and steel plant gas measurement, its scaled differential pressure is several times that of various averaging tubes, Venturi, and bent tubes, truly ensuring measurement stability and accuracy.
