1、 Product Overview:
The LUGB series vortex flowmeter is mainly used for measuring the flow rate of industrial pipeline medium fluids, such as gases, liquids, vapors, and other media. Its characteristics are small pressure loss, large range of measurement, high accuracy, and almost unaffected by parameters such as fluid density, pressure, temperature, viscosity, etc. when measuring the volumetric flow rate under working conditions. No movable mechanical parts, therefore high reliability and low maintenance. The instrument parameters can be stable for a long time. This instrument adopts a piezoelectric stress sensor with high reliability and can operate within the working temperature range of -20 ℃ to+250 ℃. There are analog standard signals and digital pulse signal outputs, which are easy to use in conjunction with digital systems such as computers, making it an ideal flow meter.
As can be seen from the above equation, the pulse frequency signal output by VSF is not affected by changes in fluid properties and composition, that is, the instrument coefficient is related to the shape and size of the vortex generator and pipeline within a certain Reynolds number range. However, as a flow meter, it is necessary to detect mass flow rate in material balance and energy metering. At this time, the output signal of the flow meter should simultaneously monitor volume flow rate and fluid density. Fluid properties and components still have a direct impact on flow metering.
The LUGB series vortex flowmeter is a new type of flowmeter that measures fluid flow in closed pipelines based on the Karman vortex principle. Due to its excellent adaptability to media, it can directly measure the volumetric flow rate of steam, air, gas, water, and liquid without temperature and pressure compensation. Equipped with temperature and pressure sensors, it can measure the volumetric flow rate and mass flow rate under standard conditions, making it an ideal replacement product for throttling flow meters.
In order to improve the high temperature and vibration resistance performance of vortex flow meters, our company's LUG improved vortex flow sensor can be used in harsh working conditions with high temperature (350 ℃) and strong vibration (≤ 1g) due to its structure and material selection.
In practical applications, large flow rates are often much lower than the upper limit value of the instrument, and with changes in load, small flow rates are often lower than the lower limit value of the instrument. The instrument does not work in the working section. To solve this problem, it is usually used to reduce the diameter at the measurement point to increase the flow rate at the measurement point, and instruments are selected to facilitate the measurement of the instrument. However, this diameter changing method requires a straight pipe section with a length of more than 15D between the diameter changing pipe and the instrument for rectification, making processing and installation inconvenient. Our company has developed an LGZ variable diameter rectifier with a longitudinal section shape of circular arc, which has multiple functions of rectification, increasing flow velocity, and changing flow velocity distribution. Its structural size is small, with * * * being 1/3 of the inner diameter of the process pipe, integrated with the vortex flow meter. It does not require an additional straight pipe section, and can also reduce the requirements for the straight pipe section of the process pipe, making installation very convenient.
For the convenience of use, the local display vortex flowmeter powered by batteries adopts low-power high-tech, and can operate continuously for more than a year with lithium battery power supply, saving the procurement and installation costs of cables and display instruments. It can display instantaneous flow, cumulative flow, etc. on site. The temperature compensation integrated vortex flowmeter also comes with a temperature sensor, which can directly measure the temperature of saturated steam and calculate the pressure, thereby displaying the mass flow rate of saturated steam. The temperature and pressure compensation integrated system is equipped with temperature and pressure sensors, which can directly measure the temperature and pressure of the gas medium for gas flow measurement, thereby displaying the standard volumetric flow rate of the gas.
2、 Working principle:
The LUGB series vortex flowmeter is composed of a vortex generator designed in the flow field, a detection probe, and corresponding electronic circuits. When a fluid flows through a vortex generator, two alternating rows of vortices are formed on both sides, which are called Karman vortex streets. On the basis of the Carmen vortex street theory, it is proposed that the frequency of the Carmen vortex street is directly proportional to the flow velocity of the fluid, and the relationship between frequency and flow velocity is given:
F=St x V/d, where:
Frequency of vortex street occurrence (Hz)
Average flow velocity on both sides of the V-vortex generating body (m/s)
St Strouhal coefficient (constant)
These alternating vortices form a series of alternating negative pressures, which act on the detection probe and generate a series of alternating electrical signals. After being converted, shaped, and amplified by a preamplifier, they output pulse frequency signals (or standard signals) that are proportional to the synchronization of the vortices.
3、 Usage selection and application:
1. For the convenience of use, the battery powered model adopts low-power high-tech, and can operate continuously for more than a year using lithium batteries, saving the procurement and installation costs of cables and display instruments. It can display instantaneous flow, cumulative flow, etc. on site.
2. The temperature compensation system also comes with a temperature sensor, which can directly measure the temperature of saturated steam and calculate the pressure, thereby displaying the mass flow rate of saturated steam.
3. The temperature and pressure compensation integrated system is equipped with temperature and pressure sensors, which can directly measure the temperature and pressure of the gas medium for gas flow measurement, thereby displaying the standard volumetric flow rate of the gas.
4. Widely used in the process metering and energy-saving management of various low viscosity liquids, gases, vapors, and single-phase fluids in industries such as petroleum, chemical, metallurgical, mechanical, papermaking, as well as urban pipeline heating, water supply, and gas.
4、 Main features:
1. Can accurately measure the flow rates of gases, liquids, and vapors over a wide range of flow rates without being affected by the physical properties of the fluid;
2. Not affected by temperature and pressure, and not easily blocked, stuck, scaled, resistant to high temperature and pressure;
3. Safe and explosion-proof, suitable for harsh environments;
4. Designed with no movable parts, no holes or gaps, the product is wear-resistant, dirt resistant, and does not require mechanical maintenance, resulting in a long service life;
5. The on-site display type flowmeter, powered by batteries and adopting low-power high-tech, can operate continuously for more than two years;
6. Integrated design of temperature and pressure compensation;
7. The current output is all electrically isolated and has good common mode interference suppression ability;
8. Simultaneously display the flow value and cumulative flow value, without the need to switch between them in turn;
9. Using anti vibration probes to effectively eliminate external vibration effects;
10. Adopting a split type signal converter with a cable length of 100 meters;
11. The range ratio reaches 20:1;
12. The overall structure design of the instrument is reasonable, with a wide dynamic measurement range and small pressure loss;
13. The meter body is made of stainless steel material, which is suitable for measuring corrosive media;
14. On site LCD display, pulse, 4-20mA output or 485 communication, can be connected to industrial automation systems.
5、 Technical parameters:
1. Measurement medium: gas, liquid, vapor;
2. Connection methods: flange clamp type, flange type, insertion type;
3. Caliber specifications: flange clamp type calibers are selected as 25,32,50,80100;
4. Select flange connection with a diameter of 100150200;
5. Flow range (see flow range table)
6. The normal measurement flow rate range is Reynolds number 1.5 × 104 to 4 × 106; Gas 5~50m/s; Liquid 0.5-7m/s;
7. Measurement accuracy of 1.0 level and 1.5 level;
8. Temperature of the tested medium: room temperature -25 ℃~100 ℃, high temperature -25 ℃~150 ℃ -25 ℃~250 ℃;
9. Output signal pulse voltage output signal high level 8-10V low level 0.7-1.3V;
10. The pulse duty cycle is about 50%, and the transmission distance is 100m;
11. Pulse current remote transmission signal 4-20 mA, transmission distance of 1000m;
12. Instrument operating environment temperature: -25 ℃~+55 ℃ Humidity: 5-90% RH50 ℃;
13. Material: stainless steel, aluminum alloy;
14. Power supply DC24V or lithium battery 3.6V;
15. Explosion proof grade: intrinsic safety type iaIIbT3-T6, protection grade: IP65.
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