Electromagnetic flow meter is ideal for conductive liquids such as Raw Water, Chilled water, effluents, Potable water etc. Using time proven electromagnetic flow metering principle, the meter achieves a flow meter for pipes from 15mm to 600mm. Since there are no moving parts, the flow meter gives years of maintenance free service.
flow-head can be supplied in Teflon lining or Hard Rubber lining is available with all the features required in a field mounted water metering equipments. These include - weather proof enclosure, communication options, RTC with data logging with printer option and 4 to 20 mA isolated Flow signal transmission option for flow pattern recording. The converter is available as field mounted-IP65 protection category. GSM modem interface can also be supplied as an optional add-on feature.
Vortex Flowmeter is based on “Karman” principle. Flow transmitter is composed of a body with the same nominal diameter and a column with triangular transect. When a column object placed in flowing fluids ( including gas and liquid ) in pipe, a series of vortexes will be generated alternately on each side of the object as shown below ( figure 1 ).
Figure 1 The principle of operation of vortex flowmeter. The frequency of the vortex shedding is proportional to the velocity, and inverse proportional to the width of column. f=St×V/d (1) Where: f-frequency of Karman Vortex shedding V – flow rate velocity St – Strouhal number D – width of column object From the expressions (1), by measuring frequency of Karman Vortex shedding can get velocity and instantaneousness. By testing, get the Strouhal number St. From frequency f of Karman Vortex shedding, know the velocity, and then get volume flow-rate. Output pulse number in period of time separate volume of fluid (corresponding shift pulses of fluid in unit volume)
Thermal sensor consists of two sensing elements - a velocity sensor and a temperature sensor that automatically corrects for changes in gas temperature(figure1). The transducer electronics heats the velocity sensor to a constant temperature differential above the gas temperature and measures the cooling effect of the gas flow. The electrical power required to maintain a constant temperature differential is directly proportional to the gas mass flow rate.In order to keep the stable temperature between Ts and Ta, circuit should be provided higher power. The range of power is related to the mass flow rate of liquid. Through test the output of power can get the mass flow rate. Furthermore, the heat on the heated velocity sensor bring by the move of gasses not cause the heat exchange. So this kind of flowmeter can measure all kinds of gases. The table of AT Series Air Flowmeter please see figure.
Vortex flowmeter (VSF) is a kind of the vibration meters. It simple configuration, and install conveniently. It can measure and control various liquid (e.g.: water, oil, petroleum, alcohol, acid, alkali and different chemical fluids) gas (e.g.: air, oxygen, N2, natural gas, coal gas), and steam (e.g.: saturation steam, overheated water vapor).Thermal sensor consists of two sensing elements - a velocity sensor and a temperature sensor that automatically corrects for changes in gas temperature(figure1). The transducer electronics heats the velocity sensor to a constant temperature differential above the gas temperature and measures the cooling effect of the gas flow.
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