1、 Overview

Turbine flowmeter (hereinafter referred to as TUF) is the main type of impeller flowmeter, which also includes anemometer, water meter, etc. Among various flow meters, TUF, volumetric flow meter, and Coriolis mass flow meter are the three types of products with the best repeatability and accuracy. TUF has its own characteristics, such as simple structure, few processed parts, light weight, easy maintenance, large flow capacity (large flow rate that can pass through the same caliber), and adaptability to high parameters (high temperature, high pressure, and low temperature). So far, this type of flowmeter product can achieve technical parameters such as a diameter of 4-500mm, a pressure of 60MPa, and a temperature of -20-300 ℃, which are difficult to achieve for the other two types of flowmeters.

LWGYThe series of turbine flow sensors (hereinafter referred to as sensors) are based on the principle of torque balance and belong to speed flow meters. Sensors have the characteristics of simple structure, lightweight, high accuracy, good reproducibility, sensitive response, and easy installation, maintenance, and use. They are widely used in industries such as petroleum, chemical, metallurgical, water supply, and papermaking, and are ideal instruments for flow measurement and energy conservation.

Sensors and display instruments are used in conjunction, suitable for measuring liquids in closed pipelines that do not corrode stainless steel 1Cr18Ni9Ti, 2Cr13, corundum Al2O3, hard alloys, and have no impurities such as fibers or particles. If matched with display instruments with special functions, quantitative control, over limit alarm, etc. can also be performed. Choose the explosion-proof type (Exm) of this productIIT6),Can be used in environments with explosive hazards.

The sensor is suitable for media with viscosity less than 5 × 10-6m2/s at operating temperature. For liquids with viscosity greater than 5 × 10-6m2/s, the sensor needs to be calibrated with real liquid before use.

2、 Working principle

Figure 1 shows the structure diagram of the TUF sensor. As can be seen from the figure, when the measured fluid flows through the sensor, the impeller is forced to rotate under the action of the fluid, and its speed is proportional to the average flow velocity of the pipeline. The rotation period of the impeller changes the magnetic resistance value of the magneto electric converter. The magnetic flux in the detection coil undergoes periodic changes, generating a periodic induced potential, that is, an electrical pulse signal. After amplification by an amplifier, it is sent to the display instrument for display.
The practical flow equation for TUF is
Qv=f/K (7.1) qm=qv ρ (7.2), where qv and qm - are the volumetric flow rates, respectively, m3/s，
Quality flow, kg/s；
F - frequency of the output signal of the flowmeter, Hz；
The instrument coefficient of K-flowmeter, P/m3。

The instrument coefficient of the sensor is verified by a flow verification device, which completely ignores the flow mechanism of the fluid inside the sensor. The sensor is treated as a black box, and its conversion coefficient is determined based on the input (flow rate) and output (frequency pulse signal), which is convenient for practical applications. However, it should be noted that this conversion coefficient (instrument coefficient) is conditional, and its verification condition is a reference condition. If it deviates from this condition during use, the coefficient will change depending on the sensor type, pipeline installation conditions, and fluid properties parameters.

Vortex Flowmeter、Electromagnetic Flowmeter、ultrasonic flowmeter、Gas turbine flowmeter、Elliptical gear flowmeter、

Precession vortex flowmeter、Metal tube float flowmeter、Mass flowmeter、Small flow micro flowmeter、Non standard customized flowmeter、Liquid turbine flowmeter、differential pressure transmitter、orifice meter、pressure transmitter、temperature transmitter、 Liquid level, material level, material level gauge、Insertion flowmeter、Flow totalizer、Anuba flowmeter、Quantitative flow controller、Submersible flowmeter、Remote video transmitter、PH/ORPMeasuring instrument、Universal flow display instrument、Ultrasonic Open Channel Flowmeter、Automatic monitoring recorder.

3、 Product Features

1）High precision, generally ± 0.25% R - ± 0.5% R for liquids, and up to ± 0.15% R for high-precision types; while for gases, it is generally ± 1% R - ± 1.5% R, and for special types, it is ± 0.5% R - ± 1% R. Among all flow meters, it is the most accurate.
2) Good repeatability, short-term repeatability can reach 0.05% -0.2%, precisely because of its good repeatability, such as frequent calibration or online calibration can achieve extremely high accuracy, it is the preferred flowmeter in trade settlement.
3) Output pulse frequency signal, suitable for total measurement and computer connection, no zero drift, strong anti-interference ability. High frequency signals (3-4kHz) can be obtained with strong signal resolution.
4) Wide range, with a medium to large caliber of up to 40:1-10:1 and a small caliber of 6:1.
5) Compact and lightweight structure, easy installation and maintenance, and high circulation capacity.

6）Can be made into an insertion type, suitable for measuring large diameters, with low pressure loss, low price, can be removed without interruption, and easy installation and maintenance.Guangzhou Minghong Automation Instrument Co., Ltd

4、 Basic parameters and technical performance

1Basic parameters: see Table 1

2Measurement range and work pressure

5、 Instrument classification
1According to the classification of instrument functions, the LWGY series turbine flowmeter can be divided into two categories, namely:
Intelligent integrated turbine flowmeter with turbine flow sensor/transmitter
2. Function Description

Guangzhou Minghong Automation Instrument Co., LtdTurbine flow sensor/transmitter manufacturer direct sales

This type of turbine flow product itself does not have on-site display function, only transmitting and outputting flow signals remotely. Flow signals can be divided into pulse signals or current signals (4-20mA); The instrument is inexpensive, highly integrated, and compact in size, making it particularly suitable for use with computer control systems such as secondary displays, PLCs, and DCS.
This type of turbine flow product is divided into two types: basic type and explosion-proof type (ExdIIBT6), as shown in the diagram

Basic sensor/transmitter Explosion proof sensor/transmitter

According to different output signals, this type of product can be divided into LWGY - □ N type and LWGY - □ A type

LWGY-N-type sensor: powered by 12-24VDC, three wire pulse output, high level ≥ 8V, low level ≤ 0.8V; signal transmission distance ≤ 1000 meters;
LWGY - □ A type transmitter: 24VDC power supply, two-wire 4-20mA output, signal transmission distance ≤ 1000.

Intelligent integrated turbine flowmeter

A new intelligent instrument integrating turbine flow sensor and display integration developed using advanced ultra-low power single-chip microcomputer technology, with dual row LCD on-site display, has obvious advantages such as compact structure, intuitive and clear reading, high reliability, no external power interference, lightning resistance, and low cost. The instrument has three-point correction of instrument coefficient, intelligent compensation of instrument coefficient nonlinearity, and can be corrected on site. The high-definition LCD display simultaneously displays instantaneous flow rate (4 significant digits) and cumulative flow rate (8 significant digits, with reset function). Keep all valid data intact for 10 years after power failure. This type of turbine flowmeter is an explosion-proof product with an explosion-proof rating of ExdIIBT6.

This type of turbine flowmeter can be divided into LWGY - □ B type and LWGY - □ C type according to the power supply method and whether it has remote signal output.

LWGY-Type B: The power supply uses a 3.6V10AH lithium battery (which can operate continuously for more than 2 years); No signal output function.
LWGY - □ C type: The power supply adopts 24VDC external power supply, outputs 4-20mA standard two-wire current signal, and can add RS485 or HART communication according to different on-site needs.

6、 Instrument selection