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Hefei high-tech zone technology avenue, number 75

LLQZ Smart Gas Roots Flowmeter

Current location:Home page -> Product -> Gas Flowmeter

■Product Introduction
LLQZ smart gas roots flowmeter is a positive displacement gas flowmeter with a pair of roots rotors. It has temperature-pressure compensation with biult-in temperature and pressure sensors. It has characteristics of high precision, wide measuring range, compact structure, etc.. It is widely used in measurement of natural gas, city coal gas, LPG, propane, butane, air, nitrogen and industrial inert gases.

In addition to the production of liquid crystal special waist wheel flowmeter, also introduced a gas-specific waist wheel flowmeter. LLQZ-type intelligent gas waist wheel flowmeter is based on the waist wheel shape of the double rotor positive displacement of the volume of gas flow meter, with built-in temperature and pressure sensors as one, to achieve temperature compensation compensation intelligent integrated flowmeter. It is characterized by high measurement accuracy, measurable range, compact structure, etc., can be widely used in natural gas city gas, liquefied petroleum gas, propane, butane, air, nitrogen and other industrial inert gas.

■How it works
Gas waist wheel flowmeter and liquid dedicated waist wheel flowmeter, is a kind of volumetric flowmeter. The metering chamber is two cross sections, which are rotated by the rotor of the waist wheel shape. As the gas flows from the metering chamber, the differential pressure generated between the metering chamber inlet and the outlet acts on the two lumbar ports connected to a pair of high precision synchronous gears The rotor rotates on the rotor to complete the following process from the ABCD rotation process, a pair of waist wheel rotor and metering chamber formed between the inner wall and the confined space formed between the metering chamber of the gas and periodic The speed of the waist wheel rotor is proportional to the flow rate of the measured gas flowing through the flowmeter. The speed value is transmitted through the special sensor to the integrator to be shaped and filtered to become the standard voltage pulse Signal output. The frequency of the pulse signal is proportional to the flow rate of the fluid in the pipe. Built-in high-precision pressure and temperature sensors simultaneously measure the temperature and pressure of the fluid and send the signal into the integrated intelligent totalizer, the integrator of the flow, temperature and pressure signal conversion and through accurate calculation and integration , So as to accurately measure the standard volume of gas flow and mass flow.

■ Flowmeter Features
One. Reliable operation and long service life. High-precision and balanced waist wheel rotor, the surface of high hardness processing, no contact and wear, good lubrication environment to ensure long-term reliable operation of the flow meter.
Two. Wide flow range, low starting flow.
Three. High precision, reliable measurement performance. No need to adjust the accuracy, not subject to changes in the measurement medium conditions.
Four. Dual power supply function, both can achieve low power consumption Built-in lithium battery, you can also two-way two-wire power supply and output signal, and also have RS485 communication function.
Five. Built-in temperature and pressure compensation, can directly compensate for real-time density, the total volume of the medium volume flow.
Six. INTEGRATED INTELLIGENT INTEGRATION IN STABILIZER ensures stable and reliable measurement with external interference with best process reliability.
Seven. With floating point operation and multi-terminal instrument coefficient automatically corrected, and has a fault self-diagnosis and alarm function.
Eight. Large-screen LCD display total volume, flow, temperature, pressure, density and power capacity and other parameters, and has a display function fault alarm.
Nine. With real-time data storage function, to prevent the replacement of the battery or sudden power loss when the data loss; in the power failure state, the internal data can be permanently saved, but also query a large number of historical historical data.

■ Main technical parameters
One. Flow range: 1-400m / h
Two. Nominal diameter: DN25-DN100 (mm)
Three. Pressure rating: PN1.0, PN1.6, PN2.5 (MPa)
Four. Operating temperature: medium temperature -10 ~ +60 ℃ Ambient temperature: -20 ~ +70 ℃
Five. Accuracy: 1.0, 1.5
0.2Qmax≤Q≤Qmax - ± 1.0%
Qmin≤Q≤0.2Qmax - ± 2.0%
0.2Qmax≤Q≤Qmax - ± 1.5%
Qmin≤Q≤0.2Qmax - ± 2.5%
Six. Repeatability: ≤0.3%
Seven. Range ratio: 1: 10-1: 160
Eight. Short-term overload: 1.6Qmax instrument without damage
Nine. Aluminum alloy body
Ten. Forced lubrication
Eleven. Explosion-proof grade: Exd ⅡBT4
Twelve. Protection class: IP65

■ Model and installation dimensions
One. Model specifications and basic parameters table

Model specifications Nominal diameter Flow range Size Weight
Start flow Qmin Qmax A B C
LLQZ-25 25 <0.1 1 16 253 120 316 8.5
LLQZ-50A 50 3.2 65 335 171 372 13
LLQZ-50B 50 5 100 335 171 372 13
LLQZ-80A 80 <0.16 8 160 435 171 372 18
LLQZ-80B 80 <0.25 13 250 462 241 430 35
LLQZ-100 100 <0.4 20 400 522 241 430 45

Two. Dimension drawing is as follows

Three. Installation form as shown below

Connection: flange connection (according to GB / T9112-2000)
DN25 for horizontal connection for horizontal installation

Four. Installation precautions
The pipe must be cleaned before installation
The gas filter needs to be installed before the flowmeter
Before and after the flow meter can not straight pipe
Flowmeter should be to prevent the impact of the fluid, the application of flow meter, you should first open the flow meter front valve, and then slowly open the flow meter back valve
When the opening speed should be ≤ 100mbar / s.

■ Electrical performance indicators
One. working power
Within a 3.6V lithium battery power supply, the screen real-time display battery capacity, the battery voltage in the 3.3-3.6V when the normal work, when the voltage is lower than 3.0V, the undervoltage indication. External power + 24VDC ± 15%, ripple ≤ ± 5%, when the external power supply, the internal power supply automatically disconnect, the machine from the external power supply work.
Two. Power supply (subject to power + 24V)
Mode pulse signal (three-wire system): directly to the flow sensor to detect the working mode pulse signal amplification output, high level ≥ 20V, low level ≤ 1V, transmission distance ≤ 300m.
4-20mA standard analog signal: 4-20mA standard analog signal line corresponds to 0-Qmax (standard flow), the flow range set by the flow meter, transmission distance ≤ 1500m, power supply mode +24 VDC external power supply.
RS485 interface signal: directly with the host computer network, remote media can be measured by the temperature, pressure, instantaneous flow, the standard volume flow and instrument-related parameters. And supporting the use of dedicated MODEM, can achieve telephone communication.
Three. Machine power consumption
Internal power supply: the average power consumption of 3mW, a lithium battery (15Ah) can be used for more than two years.
External power supply: machine power consumption ≤ 1W.
Four. Real-time data storage function
In order to meet the needs of data management, increased real-time data storage capabilities, including:
The last 400 start-up times and the corresponding net flow value
Net monthly traffic for the last 12 months
The last 360 days of net daily traffic
The above data can be read using the laptop or desktop computer through the RS485 interface to read, according to the user to form a data report and graph for analysis.

■ gas waist wheel flowmeter product model marker table

Type code LLQ Gas waist wheel flowmeter
Function Z- Smart gas roots flowmeter
shell material L- Aluminum alloy material
Nominal diameter 25.........100mm From25mm to 100mm
output signal 2- Two-wire (current) output
3- Three-wire (pulse) output
Nominal pressure 1.0- 1.0Mpa
1.6- 1.6Mpa
2.5- 2.5Mpa
Accuracy class 1.0 grade 1.0
1.5 grade 1.5
communication R RS485 communication
Example: LLQZ-50B-3-2.5-1.0R
Description: Intelligent gas turbine flowmeter, 50mm diameter B type, the flow range of 5-100m ³ / h, with three-wire pulse output, aluminum alloy material,
Maximum working pressure of 2.5MPa, accuracy grade 1.0 with RS485 signal output.