MLWQ No lower limit mass flowmeterDetailed product description：

Introduction to MLWQ Unlimited Mass Flow Meter

At present, in some small and medium-sized pipes with a wide flow range, the temperature and pressure conditions fluctuate greatly. The various gas flow meters available in the market are unable to cope with this situation, and there is a problem of small range. The flow below the lower limit of the range is basically lost, which is unacceptable in some fields, especially in gas and other trade settlement situations. The full range gas flowmeter has successfully solved this problem. This flowmeter combines vortex street and hot wire measurement sensors. The lower limit of the range is measured by the hot wire principle, and the upper limit of the range is measured by the vortex street principle. The sensing elements consist of vortex street sensors, pressure sensors, and temperature sensors. The lower and upper limits of the measuring range are accurately fitted by a microprocessor, allowing the flowmeter to measure the mass flow rate of gas from 0 to the upper limit of the measuring range.

MLWQ Unlimited Mass Flow Meter

Product Technical Specifications
Working principle and characteristics
The thermal sensing element consists of two resistive temperature sensors with thermal sleeve protection. Use Wheatstone bridge to control the power of the heating sensor to maintain a constant temperature difference between the heating sensor and the reference sensor. Measure the mass flow rate of fluid by detecting the power of the heating sensor and the heat difference of the reference sensor
The principle of vortex street sensing is: when a vortex generator is set up in the fluid, regular vortices are alternately generated from both sides of the vortex generator, which is called Karman vortices. Assuming the vortex frequency is f, the average flow velocity of the measured medium fluid is v, the width of the upstream face of the vortex generator is d, and the diameter of the body is D, there are:
f=Sr*V/(1-1.25d/D)d
Sr: Strohal number
Within the Reynolds number range of 2 * 10000 to 7 * 1000000. The vortex frequency is only proportional to the flow velocity and is not affected by medium parameters such as fluid velocity and viscosity. Therefore, by detecting the frequency of the vortex, the flow rate can be accurately measured.

Characteristics of MLWQ Unlimited Mass Flow Meter Detection

ａ. The detection element does not come into contact with the fluid, with high reliability and strong adaptability to the medium
ｂ. No movable parts, wear-resistant, sturdy and simple structure
ｃ. Wide measurement range and high accuracy
ｄ. Current signal output
ｅ. Low measurement cost
Dual row LCD display, sensor, temperature and pressure compensation, and flow integrator are integrated into one design, which automatically compensates for changes in medium temperature and pressure. Therefore, it can display the mass flow rate and cumulative total amount of natural gas, coal gas, compressed air and other gases under standard conditions, and display the temperature and pressure of the measured medium in real time. No mechanical maintenance required, high reliability, strong resistance to electromagnetic interference. It can utilize the built-in RS-485 serial communication interface.

Technical parameters

Accuracy level: liquid level 0.5, gas (vapor) level 1.0
Repeatability: Liquid, 0.2% of indication, gas (vapor), 0.3% of indication
Measurement medium: liquid, gas, steam (including various corrosive media)
Specifications: Diameter 25, 40, 50, 80, 100, 150, 200, 250, 300 (mm)
Range: Full range Medium temperature: -40 ℃ to+350 ℃
Power supply: external supply+24V · DC (± 10%) (or 220V~AC)
Data output signal 4-20mA (maximum load 700 Ω) RS-485 communication interface
Table body material: 1Cr18Ni9Ti
Flow velocity measurement range: liquid: 0.4~7m/s, vapor: 5~60m/s, steam: 6~70m/s
Reynolds number measurement range: Normal Reynolds number (Re) range: 2x10000~7x1000000, Extended Reynolds number (Re) range: 1x10000~7x1000000
Medium pressure: 1.6Mpa, 2.5Mpa, 10Mp
Response time 1 second
Repeatability+0.2% FS
Applicable occasions: Explosion proof Exd II CT1-T6.

MLWQ Unlimited Mass Flow Meter