Intelligent vortex street flowmeter
I. product overview
Zw-lugb series intelligent vortex flowmeter is a kind of velocity flowmeter which is supported by piezoelectric crystal or differential capacitance as detection component, according to karman vortex theory, using the natural vibration principle of fluid. This product USES the unique differential technology, coordinated the isolation, the shield, the filter and so on the measure, has overcome the similar product seismic resistance poor, the noise big, the small signal data disturbance and so on the question, and has adopted the unique inspection probe encapsulation new technology and the protection measure, guaranteed the product the reliability.
The product has three measurement methods: basic type, differential pressure type and temperature and pressure compensation type. The basic type measures the flow signal of a single working condition, and the differential pressure compensation type directly measures the mass flow. The temperature and pressure compensation type can measure the temperature, pressure and flow signal at the same time. The product has two kinds of structure forms: pipe type and plug-in type, which can be displayed on site or transmitted over long distance. Each type has the specification of high temperature, high pressure, anticorrosion, explosion-proof and so on.
Zw-lugb series intelligent vortex flowmeters have a series of advantages, such as wide range ratio, high precision, convenient installation and maintenance and wide adaptability of medium. Can be widely used in petroleum, chemical, metallurgy, machinery, food, papermaking, medicine, as well as urban pipe heating, gas and other industries of low viscosity liquid, other, steam and other single-phase fluid process measurement and energy conservation management.
Ii. Working principle
The measuring principle of zw-lugb series intelligent vortex flowmeters is composed of the vortex generator designed in the flow field, the detection probe and the corresponding electronic circuit. When the fluid flows through the vortex body, it forms two alternating rows of vortexes on both sides, which is known as karman vortex street. On the basis of karman vortex street theory, it is proposed that the frequency of karman vortex street is proportional to the flow velocity of fluid, and the relationship between frequency and flow velocity is given as: f = St V/d, where:
Frequency of vortex street f (Hz)
Average velocity on both sides of V vortex body (m/s)
St strohal coefficient (constant)
These alternating vortexes form a series of alternating negative pressure, which ACTS on the detection probe and generates a series of alternating electrical signals. After the preamplifier conversion, shaping and amplification processing, the pulse frequency signal (or standard signal) that is in direct proportion to the vortex synchronization is output.
Iii. Selection and application:
1. For the convenience of use, the battery power supply adopts the micro power consumption high and new technology, and the lithium battery power supply can be operated continuously for more than one year, which saves the cost of purchasing and installing cables and display meters, and can display instantaneous flow and cumulative flow on the spot.
2. Temperature compensation-type vortex flowmeter also has a temperature sensor, which can directly measure the temperature of saturated steam and calculate the pressure, thus showing the mass flow rate of saturated steam.
3, temperature and pressure compensation type with temperature, pressure sensor, used for gas flow measurement can directly measure the temperature and pressure of the gas medium, so as to show the standard gas volume flow.
4, widely used in petroleum, chemical, metallurgy, machinery, papermaking, and urban pipe heating, water supply, gas and other industries of low viscosity liquid, gas, steam and other single-phase fluid process measurement and energy-saving management.
Iv. Main features:
1. Can accurately measure the flow of gas, liquid and steam in a wide flow range without being affected by the physical properties of the fluid;
2, not affected by temperature, pressure, and not easy to plug, not easy to card, not easy to scale, high temperature, high pressure;
3. Safe and explosion-proof, suitable for harsh environment;
4, no moving parts, no holes and crevices design, no wear, no dirt, no mechanical maintenance, long service life;
5, the use of micro-power consumption high-tech, battery-powered field display type flowmeter, can not cut power operation for more than two years;
6. Integrated design of temperature and pressure compensation;
7. All current outputs are electrically isolated, with good common mode interference suppression ability;
8. Display the flow value and cumulative flow value at the same time, no need to switch in turn;
9. Anti-vibration probe is adopted to effectively eliminate the influence of external vibration;
10, using split signal converter, zui cable length of 100 meters;
11, the range ratio is up to 20:1;
12. The overall structure of the instrument is designed reasonably, with wide range of dynamic measurement and small pressure loss;
13, the table body is made of stainless steel, which can be applied to the measurement of corrosive media;
14, liquid crystal display, pulse, 4 ~ 20mA output or 485 communication, can be connected with industrial automation system.
V. technical parameters:
1. Measuring medium: gas, liquid and vapor;
2. Connection: flange clamping type, flange type and plug-in type;
3. The diameter of flange mounting type is selected as 25,32,50,80,100;
4. The diameter of flange connection type is selected as 100,150,200;
Flow measurement range normal measurement flow velocity range Reynolds number 1.5 104 ~ 4 106; Gas 5 ~ 50m/s; Liquid 0.5 ~ 7m/s;
6. Measuring accuracy is at level 1.0 and level 1.5;
7, the temperature measured medium: normal temperature - 25 ℃ ~ 100 ℃, high temperature - 25 ℃ ~ 150 ℃ to 25 ℃ ~ 250 ℃;
8, output signal pulse voltage output signal high level 8 ~ 10V low level 0.7 ~ 1.3v;
9. The pulse duty cycle is about 50%, and the transmission distance is 100m;
10. The pulse current transmits the signal 4 ~ 20 mA and the transmission distance is 1000m;
11, instrument: using the environment temperature 25 ℃ ~ + 55 ℃, humidity: 5 ~ 90% RH50 ℃;
12. Material: stainless steel, aluminum alloy;
13. Power supply DC24V or 3.6v lithium battery;
14. Explosion-proof grade: intrinsically safe iaiibt3-t6, protection grade: IP65.