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For the turbine flowmeter body, it is best to use 316 stainless steel to prevent corrosion. Its bearings are generally available in three types: tungsten carbide, polytetrafluoroethylene, and carbon graphite. Tungsten carbide offers the highest precision and is used as a standard component in industrial control applications ； Polytetrafluoroethylene and carbon graphite provide corrosion resistance, and they are generally given priority in chemical processing facilities. The lifespan of bearings is inversely proportional to the square of the flow velocity; therefore, it is better to use a flow velocity that is 1/3 of the maximum flow velocity. The sensing probe of a turbine flow meter detects the movement of the rotating element and converts it into pulse digital signals. The voltage output of its electromagnetic coil follows a near-sine curve, and the frequency of the pulse signals varies linearly with the volume of flow being measured; typical ratios are 10:1, 25:1, and 100:1. The resistance of an electromagnetic coil is generally less than 2000Ω; values higher than this may cause damage. Installation of turbine flowmeters: (1) The power cable of the transmitter should be a metal-shielded cable, with reliable and proper grounding. The power supply is 24V DC with an impedance of 650Ω. (2) The transmitter should be installed horizontally, avoiding vertical installation, and appropriate straight pipe sections should be ensured in front of and behind it, generally 10D in front and 5D behind. (3) Ensure that the flow direction of the fluid is consistent with the arrow direction on the instrument enclosure; it must not be installed in the reverse direction. (4) The medium under test must not be corrosive to the turbine, especially at the bearings; otherwise, measures should be taken. (5) Be careful not to collide with the magnetic induction section. The standard calibration method for turbine flowmeters is the ten-point water calibration method; however, the calibration values vary depending on viscosity, so it is usual to create a viscosity calibration curve. The task of its display instrument is to convert the number of pulses output per unit time and the total number of pulses output into the instantaneous flow rate and the total flow rate, and to display them. The pulse signals output by the preceding amplifier have irregular amplitudes and waveforms. Upon entering the display instrument, they must first be shaped by a shaping circuit into regular rectangular pulse signals with a fixed amplitude. Subsequently, a frequency/current conversion circuit is used to transform the frequency signal into a corresponding current signal (4–20 mA), which is then used to determine the instantaneous flow rate; the total volume is determined by the conversion and integration circuits. Some display instruments show the readings on-site, while others send the data to the DCS for display. For more information, please visit the company’s official website at http://www.yb1518.com/. Please keep this link when reproducing the content! http://www.yb1518.com/UploadFiles/20101111113351160.jpg