Vortex Flow Meter Instruction Manual

　　I. Overview

　　The LUXZ series vortex flow meter is a new type of gas flow meter developed and researched by our company with a leading domestic level. This flow meter integrates flow, temperature, and pressure detection functions, and can automatically compensate for temperature, pressure, and compressibility factor. It is an ideal instrument for gas measurement in the petroleum, chemical, power, and metallurgical industries.

　　1.1 Main Product Features

　　l No mechanical moving parts, not easy to corrode, stable and reliable, long life, long-term operation does not require special maintenance;

　　l Uses a 16-bit computer chip, high integration, small size, good performance, strong overall function;

　　l The flow meter integrates the flow probe, microprocessor, pressure, and temperature sensor into one unit, adopting a built-in combination, making the structure more compact. It can directly measure the flow, pressure, and temperature of the fluid, and automatically and real-time track compensation and compressibility factor correction;

　　l The dual detection technology effectively improves the detection signal strength and suppresses interference caused by pipeline vibration;

　　l It adopts the domestically leading intelligent anti-vibration technology, effectively suppressing interference signals caused by vibration and pressure fluctuations;

　　l It uses a Chinese character dot matrix display screen, with multiple digits displayed, intuitive and convenient reading, directly displaying the volume flow rate under working conditions, the volume flow rate under standard conditions, the total amount, as well as parameters such as medium pressure and temperature;

　　l Using EEPROM technology, parameter setting is convenient, can be permanently saved, and can save up to one year of historical data;

　　l The converter can output frequency pulses, 4～20mA analog signals, and has an RS485 interface, which can be directly connected to a microcomputer, and the transmission distance can reach 1.2km;

　　l Multiple physical quantity parameter alarm output, one of which can be selected by the user;

　　l The flow meter head can rotate 360 degrees, making installation and use simple and convenient;

　　l In cooperation with our company's FM-type data acquisition instrument, remote data transmission can be carried out through the Internet or telephone network.

　　l Pressure and temperature signals are input by sensors, with strong interchangeability;

　　l The overall power consumption is low, and it can be powered by an internal battery or an external power supply.

　　1.2 Main Applications

　　The LUXZ vortex flow meter can be widely used in the petroleum, chemical, power, metallurgical, and urban gas supply industries to measure the flow rate of various gases. It is currently the preferred product for oilfield and urban natural gas transmission and distribution measurement and trade measurement.

 

　　II. Structure and Working Principle

　　2.1 Flow Meter Structure

　　The flow meter consists of the following seven basic components (Figure 1):

　　1. Vortex generator

　　Made of aluminum alloy, with spiral blades at a certain angle. It is fixed in front of the contracting section of the shell, forcing the fluid to produce strong vortex flow.

　　2. Shell

　　It has flanges and a fluid channel of a certain shape. Depending on the working pressure, the shell material can be cast aluminum alloy or stainless steel. (Figure 1)

　　3. Intelligent flow meter integrator (principle see Figure 3)

　　It consists of temperature and pressure detection analog channels, flow detection digital channels, a microprocessor, a liquid crystal drive circuit, and other auxiliary circuits, and is equipped with external signal interfaces.

　　4. Temperature sensor

　　Uses a Pt100 platinum resistance as the temperature sensitive element. Within a certain temperature range, its resistance value corresponds to the temperature.

　　5. Pressure sensor

　　Uses a piezoresistive diffused silicon bridge as the sensitive element. The bridge arm resistance will change as expected under the action of external pressure. Therefore, under the action of a certain excitation current, the potential difference between its two output ends is proportional to the external pressure.

　　6. Piezoelectric crystal sensor

　　Installed near the throat of the shell expansion section, it can detect the frequency signal of vortex precession.

　　7. Vortex eliminator

　　Fixed at the outlet of the shell, its function is to eliminate vortex flow to reduce the impact on the performance of downstream instruments.

　　2.2 Working principle

　　The flow path of the flow sensor is similar to the profile of a Venturi tube (Figure 2). A set of spiral guide vanes is installed on the inlet side. When the fluid enters the flow sensor, the guide vanes force the fluid to generate strong vortex flow. When the fluid enters the diffusion section, the vortex flow is subjected to backflow, and begins to rotate secondary, forming a gyroscopic vortex precession phenomenon. The precession frequency is proportional to the flow rate and is not affected by the physical properties and density of the fluid. The detection element measures the secondary rotation precession frequency of the fluid, which can obtain good linearity in a wide flow range. The signal is amplified, filtered, and shaped by a preamplifier to convert it into a pulse signal proportional to the flow velocity, and then sent to the microprocessor along with the temperature and pressure detection signals for cumulative processing. Finally, the measurement results (instantaneous flow rate, cumulative flow rate, and temperature and pressure data) are displayed on the LCD screen.

　　III. Main Technical Parameters and Functions

　　(Table 1)

Model	Nominal diameterDN(mm)	Flow range (m3/h)	Nominal pressure (MPa)	Pressure loss (kPa)	Housing Material
LUZX-015	15	0.3~12	1.6   2.5   4.0   6.3	△P=ρ/1.205×PN	Stainless steel1Cr18Ni9Tior aluminum alloyZL101A
LUZX-020	20	1.2~15
LUZX-025	25	2.5~30
LUZX-032	32	4.5~60
LUZX-040	40	7~70
LUZX-050	50	10~130
LUZX-065	65	20~300
LUZX-080	80	30~400
LUZX-100	100	50~800
LUZX-125	125	80~1000
LUZX-125	150	190~1900
LUZX-200	200	240~3600

　　Note: 1. Accuracy: The system accuracy after temperature and pressure correction;

　　2. Standard state conditions: P=101.325KPa，T=293.15K

　　3. Conditions of use:

　　Ambient temperature: -30℃～+65℃

　　Relative humidity: 5%～95%

　　Medium temperature: -20℃～+80℃

　　Atmospheric pressure: 86KPa～106KPa

　　4.3 Flow meter dimensions and installation dimensions drawing

　　The dimensions of the flow meter are shown in Figure 3. The un-noted dimensions in the figure are listed in Table 1. The flow meter uses a flange connection method, and the flange dimensions comply with the GB/T9112～9113-2000 standard.

　　(Table 2)

　　(Table 3)

 

 

(Table1)

Model	Nominal diameterDN(mm)	Flow range (m3/h)	Nominal pressure (MPa)	Pressure loss (kPa)	Housing Material
LUZX-015	15	0.3~12	1.6   2.5   4.0   6.3	△P=ρ/1.205×PN	Stainless steel1Cr18Ni9Tior aluminum alloyZL101A
LUZX-020	20	1.2~15
LUZX-025	25	2.5~30
LUZX-032	32	4.5~60
LUZX-040	40	7~70
LUZX-050	50	10~130
LUZX-065	65	20~300
LUZX-080	80	30~400
LUZX-100	100	50~800
LUZX-125	125	80~1000
LUZX-125	150	190~1900
LUZX-200	200	240~3600