Plug-in Vortex Flow Meter

HQLUGB intelligent vortex flowmeter is a new design concept that integrates temperature, pressure, and flow signals. Through an intelligent digital processor, the three signals are mixed and processed to output a compensated standard flow rate, thereby achieving temperature and pressure compensation for gas and steam. Due to the adoption of an intelligent integrated design concept, LUGB temperature and pressure compensation intelligent vortex street has the characteristics of compact structure, easy installation, use, and maintenance. Integrated intelligent vortex flowmeters have excellent shock resistance and interference resistance performance and widely applicable (the flow rates of steam, gas, and liquid can be measured).

The intelligent vortex flowmeter is a new type of flowmeter developed based on the Karman vortex principle, which has international advanced level. Due to its unique advantages that cannot be achieved by other flow meters, it has developed rapidly since the 1970s. According to relevant data, the proportion of smart vortex flow meters used in developed countries such as Japan, Europe, and America has increased significantly and has been widely applied in various fields. It will occupy a leading position in future flow meters and is the most ideal alternative product for orifice flow meters. Intelligent vortex flowmeter is suitable for measuring the mass flow rate and volume flow rate of superheated steam, saturated steam, compressed air, general gases, water, and liquids.

HQ-LUGB intelligent vortex flowmeter produced by our company includes remote transmission type, on-site display type, and temperature and pressure automatic compensation type. It can be widely used in chemical, petroleum, metallurgy, light industry, environmental protection, municipal, power and other sectors.

1. The structure is simple and sturdy, with no movable parts, high reliability, and very reliable for long-term operation.

2. Easy to install and very convenient to maintain.

3. The detection sensor does not directly contact the measured medium, with stable performance and long lifespan.

4. The measured pulse signal is proportional to the flow rate, with no zero drift and high accuracy.

5. The measurement range is wide, and the range ratio can reach 1:10.

6. Less pressure loss, lower operating costs, and more energy-saving significance.

7. Adopting ultra-low power consumption technology, battery powered operation can last for more than two years.

8. Integrated design of temperature and pressure compensation, displaying both flow value and cumulative flow value, temperature and pressure values without the need for alternating switching.

Nominal diameter: pipeline type DN15~DN300; Insertion type DN200~DN5000

Range ratio: 10:1

Pressure level: PN25, PN40 (high voltage can be specially manufactured)

Power supply mode: 12-36VDC or 3.6V Battery

Output signal: two-wire 4-20mA

Current output on site display: programmable display instantaneous flow, cumulative flow

Communication method: RS485 Communication

Protection level: IP67

Medium temperature: -35 ℃ -+350 ℃; Insertion type -50 C -+400 ℃

Measurement accuracy: Liquid: ± 1.0% of measurement value (special), Gas: ± 1.5% of measurement value

4. Working Principle:

When the medium flows through a triangular cylinder at a certain flow rate, an alternating vortex band is generated at both ends of the triangular cylinder, called the "Karman vortex street" . As a result, pressure pulsations are generated at both ends of the cylinder, causing alternating stress to be generated in the detection body. The piezoelectric element encapsulated in the detection probe generates an alternating charge signal with the same frequency as the vortex under the action of the alternating stress. The amplifier amplifies, filters, and shapes this charge signal into a square wave, which is then sent to the integrator for processing and display. The relationship between the release frequency f of vortices within a certain Reynolds number range (2X104~7x106) and the flow velocity V, as well as the width d of the upstream face of the vortex generator, can be expressed by the following equation: f=Sr.v/d, where Sr is the Strouhal number. In the straight part of the curve with Sr=0.16, as long as the vortex frequency f is measured, the fluid flow velocity can be measured. Thus achieving the purpose of measuring fluid flow rate. 

★ Measurement medium: liquid, gas, superheated/saturated steam

★ Measurement range: Normal working range, Reynolds number is 20000~7000, 000; The possible range for measurement is Reynolds number from 8000 to 7000,

★ Accuracy: a. Liquid,+1.0% of the indicated value;

                     b. Gas,+1.5% of the indicated value;

                     c. Steam, with an indication value of 1.5% soil;

★ Repeatability: 1/3 of accuracy;

★ Output signal: a. Three wire voltage ripple low level; High level: greater than 4V: duty cycle 50%

                            b. Two wire system current 4mA~20mA

                            c. Three wire system current 4mA~20mA

                            d. RS-485 communication interface

★ Working power supply: external power supply;  +24VDC； Internal power supply 3.6V lithium battery

★ Medium temperature: Ordinary type: -40 ℃~+130 ℃;

     High temperature type: -40 ℃~+250 ℃;

     Ultra high temperature type: -10 ℃~+350 ℃ optional;

     Explosion proof type: -40 ℃~+80 ℃;

★ Working pressure: 2.5MPa (Note: Other pressure levels of flow meters can be provided upon user request, but customization is required)

★ High pressure: 86KPa~106KPa;

★ Shell material: a. Carbon steel; b. Stainless steel (1Cr18Ni9Ti)

★ Specifications (inner diameter of pipeline): 20, 25, 32, 40, 50, 65, 80, 100, 125, 150, 200, 250, 300

★ Environmental temperature: -30 ℃~+60 ℃

★ Relative temperature: 5%~95%

★ Protection level: IP65

★ Explosion proof type: Explosion proof type; Explosion proof mark: Exd I BT4

★ Flow range under working conditions (unit: m³/h)

6. Selection

The flowmeter consists of a body, a support column, and an amplifying display device. There are two ways to connect with pipelines, namely flange clamping and flange connection.

The correct selection of instruments is the key to their normal application. In practical applications, most faults are caused by unreasonable instrument selection. Thoroughly understand the working conditions and medium parameters of the on-site application, select appropriate pressure, temperature, protection, explosion-proof level, material, and structural method to ensure that the instrument can operate in the best possible state.

The maximum flow rate used by the instrument should be as low as 0.5Qgmax (upper limit flow rate of the instrument) as possible

The nominal diameter of the instrument shall be selected based on the maximum flow rate under operating conditions. If the measured flow rate is at the standard state (20 ℃, 101.3kPa), it is necessary to convert the operating flow rate and select the appropriate diameter according to Selection Table.

(1) The flow range of the intelligent vortex flowmeter has been calibrated according to national standards before leaving the factory, and in general, users do not need to calculate it; When necessary, users can calculate the lower limit value of the medium flow rate under operating conditions according to the following formula.

Qgmin=QgminX

In the formula, under the QGmin operating condition, the lower limit of the supported flow rate is:

QGmin Table 1 shows the minimum flow rate under the reference conditions:

Under the reference conditions of ρ tab, the medium density [liquid (water) ρ tab=1000 (kg/m³), gas (air)] ρ tab=(1.205 (kg/m³), dry saturated vapor ρ tab=2.129 [(kg/m³)]; Density of medium under operating conditions of ρ g (kg/m³).

(2) The calculation of converting the standard state (101.3kPa, 20C) density of gas into the density under operating conditions;

ρ g=pn. [(101.3+Pg)/101.3]. [(273+20)/(273+T)] In the equation: density of the medium under pg operating conditions (kg/m³)

Ρ n: Medium density (kg/m³) under standard conditions (101.3kPa, 20C);

Pg working condition pressure (kPa); Temperature under T condition (℃);

(3) Calculate the operating flow rate (Qg);

a) Calculate the volumetric flow rate under operating conditions from the volumetric flow rate under standard conditions: Qg=Qg (pn/pg)

Qg=Qn.[101 .3/(101. 3+Pg)].[(273+T)/<273+20)]

In the formula: Qg operating condition flow rate (m³/h);

Qn standard flow rate (m³/h);

Density of medium under operating conditions of ρ g (kg/m³)

Density of the medium under standard conditions of ρ n (kg/m³); Pg working condition pressure (kPa);

Temperature under T condition (℃)

b) Calculate the flow rate (Qg) of the operating condition based on the mass flow rate;

Qg=Qm/g

In the formula: Qg operating condition flow rate (m³/h);

Qm mass flow rate (m³/h);

Density of the medium under operating conditions of ρ g (kg/m³);

(4) When measuring liquids, in order to prevent gas pockets and cavitation, the actual working pressure inside the pipeline should meet the requirements of the following equation;

P≥2.7△P+1.3P1

In the formula: the maximum allowable pipeline pressure for P (excellent pressure MPa);

△ P pressure loss (MPa);

P1 The corresponding saturated vapor pressure at the working temperature of the liquid (MPa excellent pressure);

△ P can be calculated by the following formula: △ P=1.079X 106p.v2

In the formula: p is the density of the measured liquid (kg/m³);

The flow velocity of the tested liquid (m/s);

Note: Gas refers to air at room temperature and pressure (t=20C, P=0. IMPa); Steam refers to dry saturated steam (t=143C, P=0.4MPa)

Intelligent Vortex Flow Meter Ordering Notice:

① When ordering this product, users should pay attention to selecting appropriate specifications based on the nominal diameter of the pipeline, flow range, nominal pressure, maximum pressure of the medium, temperature range of the medium, and environmental conditions. Explosion proof grade requirements must be indicated for use in hazardous areas.

② Flow meters are generally of the basic type with pulse output for working conditions. If other accessories and output functions are required, please specify them when placing an order.

③ When placing an order, please fill in the following format in detail and correctly.

HQ-LUGB/E Series Vortex Flowmeter Selection Table