Precession Vortex Gas Flowmeter

Precession vortex flowmeter is a new type of gas flowmeter. It can be used for the measurement of natural gas, propane, air, nitrogen and other gases.

Features of Precession Vortex Gas Flowmeter

• No mechanical moving parts, not easy to corrosion, stable and reliable, long life, long-term operation without special maintenance;
• 16 bit computer chip, high integration, small size, good performance, strong function;
• The intelligent flowmeter integrates flow probe, microprocessor, pressure and temperature sensor into one, and adopts built-in combination to make the structure more compact, which can directly measure the flow, pressure and temperature of the fluid, and automatically real-time tracking compensation and compression factor correction;
• Double probe detection technology, new sensor processing technology and reasonable installation method are adopted to greatly improve the signal strength, so that the sensor can accurately detect the signal and suppress the interference caused by pipeline vibration.
• Adopt the domestic leading intelligent anti-seismic technology, effectively restrain the disturbance signal caused by vibration and pressure fluctuation;
• The Chinese character dot matrix display screen is adopted, which can display the volume flow under working state, volume flow under standard state, total volume, medium pressure, temperature and other parameters directly.
• The converter can output frequency pulse, 4 ~ 20mA analog signal, and has RS485 interface, can be directly connected to the computer network, transmission distance up to 1.2km;
• With signal transfer output of several physical parameters, users can choose any of them.
• Pressure and temperature signals are the input mode of the sensor with strong interchangeability.
• The power consumption of the whole machine is low, which can be supplied by built-in battery or external power supply.

Specifications of Precession Vortex Gas Flowmeter

Inside nominal diameter DN (mm)	Range of  flow (m3/h)	Nominal pressure (Mpa)	Pressure  loss (kpa)	Class of accuracy	Repetitive	Shell material
15	0.6~12	1.6 2.5 4.0 6.3 10.0 16.0 25.0	△P=ρ/1.205×PN	1.0 1.5	Less than the base error limit is definitely  worth 1/3	Aluminum alloy 304 stainless  Steel
20	1~15
25	2~40
32	3~70
40	4~80
50	6~130
65	8~400
80	15~500
100	40~1000
125	50~1200
150	100~2000
200	360~3600

Further reading: Industrial LPG/Propane flow meter

Vortex Flowmeter VS. Precession Vortex Flowmeter

The common point of precession vortex flowmeter and vortex flowmeter

• Both flow meters are velocity flow meters;
• Both flow meters can be made into a temperature and pressure compensation system, and can measure various gases, such as compressed air, oxygen, biogas, natural gas, coal gas, etc.;
• Both flowmeters have no mechanical moving parts, are not easy to be corroded, are stable and reliable, have a long life, and do not require special maintenance for long-term operation;
• The highest accuracy of both flowmeters can reach 1.0%.

Biogas Flow Meters Selection Guide

The difference between precession vortex flowmeter and vortex flowmeter

• The working principles of the two flow meters are different;
• The intelligent precession vortex flowmeter can only measure gas, while the intelligent vortex flowmeter can also measure liquid and steam;
• The maximum caliber of the intelligent precession vortex flowmeter can only achieve 200 caliber, while the maximum caliber of the intelligent vortex flowmeter can achieve 1000 caliber, of which 300-1000 is a plug-in type;
• The cost performance of the intelligent precession vortex flowmeter is higher than that of the intelligent vortex flowmeter;

Precession Vortex Gas Flowmeter Structure

Flow meter is composed by below parts:

1. Swirl generation body
   Made by aluminium alloy, with certain angle screw blades, it is fixed in front of the housing contraction, then press the fluid and generate strong swirl flow.
2. Housing
   It has flange itself, and with certain shape fluid channel, according to different working pressure, the housing could adopt cast aluminium alloy or stainless steel.
3. Intelligent flow totalizer
   It is combined of temperature, pressure testing analogue channel, flow testing no. Channel and micro processing unit, LCD drive circuit and other assistant circuit, with the extermal output interfernce.
4. Temperature sensor
   Use the PT100 platinium resistance as the temperature sensitive element, under certain temperaure range, the resistance and temperature is correspond with each other.
5. Pressure sensor
   Use the diffused silicon piezoresistive type bidge road as the sensitive element, the bridge arm
   resistance will happen some expected change under pressure effect, under certain excitation current, the two output terminal potential difference in proportion to the outer pressure.
6. Piezocrystal flow sensor
   It is installed at the throat near the housing contraction section, it could test the frequency of swirl.
7. Clear swirl part
   It is fixed at the housing exit section, the function is clear the swirl and decrease the influence to the downstream instruments performance.

Precession Vortex Gas Flowmeter Working Principle

The flow profile of the Precession Vortex Gas Flowmeter is similar to the profile of a Venturi tube.

A set of spiral guide vanes are placed on the inlet side. When the fluid enters the flow sensor, the guide vane forces the fluid to produce a violent vortex. When the fluid enters the diffusion section, the vortex flow is affected by the backflow and starts to rotate twice. A gyroscopic vortex precession phenomenon is formed.

The precession frequency is proportional to the flow rate and is not affected by the physical properties and density of the fluid. The second rotation precession frequency of the fluid measured by the detecting element can obtain good linearity in a wide flow range.

The signal is amplified, filtered and shaped by a preamplifier and converted into a pulse signal proportional to the flow rate. Then, together with the detection signals of temperature and pressure, they are sent to the microprocessor for integration processing. Finally, the measurement result is displayed on the LCD screen. Including instantaneous flow, cumulative flow and temperature and pressure data.

Precession Vortex Gas Flowmeter Flow Totalizer Working Principle:

Flow totalizer is combined with temperature,pressure testing analogue channel, flow sensor channel and micro processing unit, and with the external output signal interface, with many output signals, the micro processor in the flow meter will carry out the temperature and pressure compensation according to gas state equation, and carry out the compress factor amendment. The gas state equation as below:

In the formula:
QN ——flow volume under standard condition. (m3/h)；
QV ——flow volume under working condition. (m3/h)；
Pa ——local atmospheric pressure（KPa）；
P ——flow meter tapping hole measured meter pressure（KPa）；
PN ——atmospheric pressure under standard condition.（101.325 KPa）；

TN ——absolute temperature under standard conditions.（293.15K）；
T ——the absolute temperature of measured fluid.（K）；
ZN ——the gas compression factor under standard condition. ；
Z ——the gas compression factor under working conditions；
Note: when use the bell jar or negative pressure calibrate, use ZN/Z=1, for natural gas (ZN/Z)1/2=FZ is super compression factor, calculated according to the China National Petroleum Corporation standard SY／T6143－1996 formula.

💡Industrial Propane Tank Level Indicators for Industrial Tank Level Measurement

Sino-Inst, Manufacuturer for Precession Vortex Gas Flowmeters.

Sino-Inst’s Precession Vortex Gas Flowmeters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, US, and other countries.