The Verabar flowmeter is suitable for high-precision flow measurement of gases, liquids, and vapors. Weiliba is a differential pressure and rate averaging flow sensor that measures flow by measuring the differential pressure generated by the sensor in the fluid. The power bar reflects the true flow velocity of the fluid, with an accuracy of ± 1.0% and a repeatability of ± 0.1%.

Measurement principle of Weiliba flowmeter

When fluid flows through the probe, a high-pressure distribution area is generated in its front, and the pressure in the high-pressure distribution area is slightly higher than the static pressure of the pipeline. According to the Bernoulli equation principle, the velocity of the fluid increases as it flows through the probe, creating a low-pressure distribution area at the back of the probe. The pressure in the low-pressure distribution area is slightly lower than the static pressure of the pipeline. After the fluid flows through the probe, a partial vacuum is generated at the back of the probe, and vortices appear on both sides of the probe. The cross-sectional shape, surface roughness, and position of the low-pressure tapping hole of the average velocity flow probe are key factors determining the performance of the probe. The stability and accuracy of low-voltage signals play a decisive role in the accuracy and performance of the uniform velocity probe. The Weiliba average velocity flow probe can accurately detect the average differential pressure generated by the average velocity of the fluid. The Weiliba average flow probe has multiple pairs of pressure tapping holes arranged according to certain criteria in the high and low pressure areas, making it possible to accurately measure the average flow velocity.

The Verabar flowmeter is a plug-in flow measurement instrument. Insert a Verabar sensor into the pipeline, and when fluid flows through the sensor, a high-pressure distribution area is generated in the upstream direction and a low-pressure distribution area is generated in the downstream direction. Sensors in high and low pressure zones have multiple pairs arranged according to certain rules, usually three pairs of pressure tapping holes, which measure the total pressure of the fluid, including static pressure, average velocity pressure Pl, and static pressure P2. Introduce P1 and P2 into the differential pressure transmitter respectively, and measure the differential pressure △ P=P1-P2. △ P reflects the magnitude of the average fluid velocity, which can be used to calculate the fluid flow rate.

Verabar flowmeter matching solution

1. HLV series averaging tube flow sensor. Design and produce a uniform velocity tube flow sensor based on the measured medium and the inner diameter, working temperature, working pressure, and flow rate changes of the pipeline used by the user;
2. Differential pressure transmitter or other types of differential pressure transmitter;
3. Pressure transmitters or other types of pressure transmitters;
4. Temperature transmitters or other types of temperature transmitters;
5. Flow integrator or other models of flow integrators;
   The intelligent averaging tube flow meter composed of this can be equipped with temperature and pressure compensation, and can display instantaneous flow rate, cumulative flow rate, medium temperature in the pipeline, medium pressure in the pipeline, and differential pressure, etc. It is equipped with communication interface and 4-20mA output.

Precautions for installation of Velbar flowmeter

The Weiliba flowmeter is a differential pressure and rate averaging flow sensor that measures flow by measuring the differential pressure generated by the sensor in the fluid. Suitable for high-precision flow measurement of gases, liquids, and vapors. Can be installed on any plane (horizontal, vertical, inclined). During the installation process, the influence of the measuring medium on the impulse pipeline needs to be considered. During the installation process of the Weiliba flowmeter, the following points should be noted:

1. For measuring the flow rate of gas in vertical pipelines, flow meters can be installed on the horizontal plane of the pipeline, at any position along the pipeline 360 degrees. For horizontal pipelines, the pressure joint of the flowmeter must be located below the centerline of the pipeline.
2. For measuring the flow rate of liquids in vertical pipelines, flow meters can be installed on the horizontal plane of the pipeline, at a 360 degree position along the pipeline. For horizontal pipelines, the pressure joint of the flowmeter must be located below the centerline of the pipeline.
3. When measuring the flow rate of steam, it should be noted that the two positive and negative pressure connections should be on the same horizontal plane around the vertical pipeline. The requirement for the straight pipe length of the Velbar flowmeter in differential pressure flow meters is relatively short, which is an advantage of this type of flowmeter.

Checkpoints after installation of flowmeter:

1. Instrument calibration: Carefully read the manual of the intelligent flow integrator. According to the calculation sheet attached to the Weiliba flowmeter, correctly set the parameters in the intelligent flow integrator to ensure that the integrator can correctly calculate and display the flow rate. If directly connected to the computer, the input data format and corresponding compensation method need to be set up inside the computer
2. Check the installation of the flow meter: After completing the installation of the Velbar flow meter, it is necessary to carefully inspect and ensure that the welding is firm, the direction is correct, and there is no leakage during pressure testing.
3. Instrument wiring is correct: The Velbar flowmeter, differential pressure transmitter, and flow accumulator together form a measurement system. Please double check and confirm that there are no errors before putting it into operation.
4. System preheating: After the preparation work for operation is completed, the measured medium fills the process pipeline, and the Velbar flowmeter is temporarily closed. At this time, the balance valve of the three valve group should be in the open state, and the high pressure valve and low pressure valve should be in the closed state. Turn on the instrument power and preheat for 15 minutes.
5. System operation: After preheating is completed, open the high and low pressure valves of the three valve group, fill the measured medium into the differential pressure transmitter, open the drain valve behind the differential pressure transmitter, quickly discharge the dirty liquid or gas, close the drain valve, and then close the balance valve of the three valve group. The transmitter enters the measurement state, and the flow accumulator also enters the working state, displaying the flow rate of the medium in the pipeline.

Application Fields of Velbar Flow Meter

The application of Weiliba flowmeter is extremely extensive, and the application of flow measurement technology and instruments can be roughly divided into the following fields.

The Weiliba flow meter is one of the major categories of instruments and devices in process automation. It is widely used in various fields of the national economy, such as metallurgy, power, coal, chemical, petroleum, transportation, construction, textiles, food, medicine, agriculture, environmental protection, and people’s daily lives. It is an important tool for developing industrial and agricultural production, saving energy, improving product quality, enhancing economic efficiency and management level, and occupies an important position in the national economy. In process automation instruments and devices, flow meters have two main functions: as detection instruments for process automation control systems and as total quantity meters for measuring material quantities.

Energy metering

Energy is divided into primary energy (coal, crude oil, coalbed methane, petroleum gas, and natural gas), secondary energy (electricity, coke, artificial gas, refined oil, liquefied petroleum gas, steam), and energy carrying working fluids (compressed air, oxygen, nitrogen, hydrogen, water), etc. Energy metering is an important means of scientifically managing energy, achieving energy conservation and consumption reduction, and improving economic efficiency. Flow meters are an important component of energy metering instruments. Commonly used energy sources such as water, artificial gas, natural gas, steam, and oil all use an extremely large number of flow meters, which are indispensable tools for energy management and economic accounting.

Environmental Protection Engineering

The discharge of smoke, waste liquid, sewage, etc. seriously pollutes the atmosphere and water resources, posing a serious threat to the human living environment. The country has made sustainable development a national policy, and environmental protection will be the biggest issue of the 21st century. To control air and water pollution, it is necessary to strengthen management, and the basis of management is quantitative control of pollution levels.

Transportation

There are five ways: railway and highway, aviation, water transportation, and pipeline transportation. Although pipeline transportation has long existed, its application is not widespread. With the prominent environmental issues, the characteristics of pipeline transportation have attracted people’s attention. Pipeline transportation must be equipped with flow meters, which are the eyes of control, distribution, and scheduling, as well as essential tools for safety monitoring and economic accounting.

Biotechnology

Industries characterized by biotechnology will experience rapid development. There are many substances that need to be monitored and measured in biotechnology, such as blood, urine, etc. The difficulty of instrument development is extremely high, with a wide variety of products.

scientific experiment

The flow meters required for scientific experiments are not only numerous, but also extremely diverse in variety. According to statistics, a large part of the over 100 types of flow meters are for scientific research purposes. They are not mass-produced and are sold on the market. Many research institutions and large enterprises have set up dedicated teams to develop specialized flow meters.

Marine meteorology

These fields are open channels that generally require detecting flow velocity and then calculating flow rate. The physical principles and fluid mechanics foundations on which flow meters and flow meters are based are common, but there are significant differences in instrument principles, structures, and usage conditions.