The working principle of smart turbine flowmeter

The intelligent turbine flowmeter consists of a turbine, a bearing, a preamplifier, and a display instrument. The measured fluid impacts the turbine blades and causes the turbine to rotate. The speed of the turbine changes with the change of the flow. That is, the speed of the turbine is large when the flow is large. Then the speed of the turbine is converted into electric pulses of the corresponding frequency by the magnetoelectric conversion device. After the preamplifier is amplified, it is sent to the display instrument for counting and the intelligent turbine flowmeter is composed of turbine, bearing, preamplifier, and display instrument. The measured fluid impacts the turbine blades and causes the turbine to rotate. The speed of the turbine changes with the change of the flow. That is, the speed of the turbine is large when the flow is large. Then the speed of the turbine is converted into electric pulses of the corresponding frequency by the magnetoelectric conversion device. After the preamplifier is amplified, it is sent to the display instrument for counting and display, and the instantaneous flow rate and the accumulated flow rate can be obtained according to the number of pulses per unit time and the accumulated pulse number. The working principle of the intelligent turbine flowmeter is that when the fluid flows along the axis of the pipeline and impacts the turbine blades, a force proportional to the product of the flow qv, the flow velocity V and the fluid density ρ acts on the blades to push the turbine to rotate. While the turbine is rotating, the blades periodically cut the lines of magnetic force generated by the electromagnet, changing the magnetic flux of the coil. According to the principle of electromagnetic induction, a pulsating electric potential signal will be induced in the coil, and the frequency of the pulsating signal is proportional to the flow rate of the fluid to be measured. The pulse signal output by the turbine transmitter is amplified by the front amplifier and sent to the display instrument to realize the flow measurement. 2 Selection of Intelligent Turbine Flowmeter (1) It is best to use 316 stainless steel in the area of u200bu200bthe intelligent turbine flowmeter to prevent corrosion. If it is an explosion-proof area, it must be an explosion-proof result. (2) The induction probe detects the movement of the rotating body and converts it into a pulse digital electrical signal. The voltage output value of its electromagnetic coil is close to a sinusoidal curve. The frequency range of the pulse signal changes linearly with the measured flow rate. The typical range is 10 :1, 25:1 and 100:1 three specifications. The resistance of the electromagnetic coil is generally less than 2000Ω, and it may be damaged if it is greater than this value. (3) Bearings generally have three specifications: tungsten carbide, polytetrafluoroethylene, and carbon graphite: tungsten carbide has the highest precision and is used as a standard part of industrial control; PTFE and carbon graphite can be anti-corrosion, generally preferred in chemical sites . The life velocity of the bearing is proportional to the square of the flow velocity, so the best velocity is 1/3 of the maximum velocity.