Bypass Flowmeter DST

The Kirchner Bypass Flow Meters DST for water, aggressive media, air and gas are used for large flow rates. Easy installation of the orifice plate in any position, the scale is specific to the liquid, wide choice of materials, no el. power required.

The low-cost device in PVC is frequently used in water technology. The device in PVDF is suitable for the flow measurement of aggressive media, e.g. in water treatment, while the DST-1/2 is mainly used for flow measurement of air and gases.

The measuring range extends from 0.02 – 0.16 m3/h to 300 – 1800 m3/h for H20, and from 0.15 m3/h – 1.5 to 1200 – 6000 m3/h for air at STP.

The partial flow can be turned on and off, as required, by installing two ball valves in the bypass line.By installation of electrical limit value switches,which are adjustable throughout the entire measuring range, these devices can be used as detectors

Operating Principle

The DST bypass flow meter operates on the differential-pressure-bypass method. A ring with an orifice plate is installed in the pipeline between flanges. The measuring orifice leads to a constriction and causes a differential pressure. As compensation a volume flow occurs in the bypass which is displayed by a variable area flow meter. This partial flow is proportional to the flow rate in the main pipeline.The unimpeded, straight tube length has to be 6DN before and 4 DN behind the mounting position. The partial flow can be turned on and off, as required, by installing two ball valves in the bypass line.

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