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The structure of an Emerson flowmeter, specifically for heavy oil flow measurement, involves a turbine placed at the center of the pipe, with bearings supporting it at both ends. When fluid flows through the pipe, it impacts the blades of the turbine, generating a driving torque that enables the turbine to rotate despite the frictional torque and the resistance exerted by the fluid. Within a certain range of flow rates, and for a given viscosity of the fluid medium, the rotational angular velocity of the turbine flow meter is proportional to the fluid flow velocity. The rotation speed of the Emerson flowmeter’s heavy oil turbine flowmeter is detected by a sensing coil installed outside the housing. When the vanes of the turbine flowmeter cut through the magnetic field lines generated by permanent magnets inside the housing, it causes a change in the magnetic flux in the sensing coil. The sensing coil sends the detected periodic changes in magnetic flux to the pre-amplifier, where the signal is amplified and shaped to generate a pulse signal that is proportional to the flow rate. This pulse signal is then sent to the unit conversion and flow accumulation circuit, which calculates and displays the cumulative flow value. At the same time, the pulse signal is also sent to the frequency-to-current conversion circuit, where it is converted into an analog current value, thereby indicating the instantaneous flow rate. Heavy oil is mainly measured using turbine flowmeters, as oils do not conduct electricity. Additionally, since heavy oil has a slightly alkaline pH value, the blades of turbine flowmeters are made of martensitic stainless steel, also known as rust-resistant iron. It can fully meet the measurement requirements for heavy oil, without causing any chemical reactions. Its pipes are made of 304 stainless steel and are also suitable for measuring heavy oil. It features accurate measurement and good stability; the typical precision level is 1%, while precision of 0.5% can be achieved for special requirements. It can provide pulse or 4-20mA output.