概述威力巴流量计采用了完全符合空气动力学原理的工程结构设计，是一种在精度、功效及可靠方面达到了无比卓越程度的传感元件。 I. Overview of Verabar Flowmeter Verabar flowmeter uses an engineering structure design that fully complies with the aerodynamic principle. It is a sensor element that has achieved unparalleled levels of accuracy, efficiency and reliability. 1. Verabar flowmeter application Verabar flowmeter is suitable for high-precision flow measurement of gas, liquid and steam. Verabar flowmeter is a differential pressure, rate average flow sensor, which measures the flow through the differential pressure generated by the sensor in the fluid. Verabar flowmeters reflect the true flow velocity of the fluid, with an accuracy of ± 1.0 and repeatability of ± 0.1. The outstanding advantages of Verabar are: output a very stable, pulsation-free differential pressure signal2, probe design features Probes with a cross-sectional shape of the bullet head can produce accurate pressure distribution, fixed fluid separation points; located on the two sides behind the probe side, the fluid The low-pressure tapping hole before the separation point can generate a stable differential pressure signal and effectively prevent blockage. The internal integrated structure can avoid signal leakage, improve the structural strength of the probe, and maintain long-term high accuracy. 3. Verabar probe anti-clogging design Verabar flowmeter probe with its excellent anti-clogging design, completely get rid of the shortcomings of plug-in flow probes such as Annuba, making the average blocking tube flow probe's anti-clogging level unprecedented. the height of. The high-pressure pressure taking hole of the probe will not be blocked by the front of the probe to form a high-pressure area. The pressure is slightly higher than the static pressure of the pipeline, which prevents particles from entering. Please note: The velocity of the fluid at the probe's high-pressure tapping hole is zero, and no objects will enter the tapping hole. When the machine is turned on, the fluid enters the elbow under the static pressure of the pipeline, and a pressure equilibrium state is quickly formed. When the pressure equilibrium state is formed, the fluid encounters high pressure at the inlet of the elbow, detours, and no longer enters the elbow. The low pressure orifice of Verabar flowmeter achieves essential anti-blocking. Generally, dust, sand and particles are concentrated at the back of the probe under the action of vortex force. This is why autumn leaves are always concentrated behind leeward houses. The other low-pressure pressure taking holes of other probes are taken in the vacuum area at the end of the probe. Under the action of vortex force, the low-pressure pressure taking holes of the probe are quickly blocked by impurities brought by eddy current. The unique design of the Verabar flowmeter makes the low-pressure pressure-receiving holes on the back of the probe side, the front of the fluid separation point and the trailing area. This design essentially prevents clogging and produces a very stable low-voltage signal. 4. The advantages of the probe can measure a variety of media, with a wide range of applications, high accuracy, large range ratio, and pressure taking hole. Essentially anti-blocking. The measurement signal is stable, the fluctuation is small, and the pipeline has low permanent pressure loss. Low structural installation cost, basically maintenance-free and can be installed and overhauled online.
测量系统性能指标测量精度：± 1 重复精度：± 0.1 Performance index of Verabar flowmeter measurement system Measurement accuracy: ± 1 Repeat accuracy: ± 0.1
Applicable pressure: 0 ～ 40MPa Applicable temperature: － 180 ℃ ～ ＋ 550 ℃
Upper measurement limit: Depends on the probe strength. Lower measurement limit: Depends on the minimum differential pressure required. Range ratio: greater than 10: 1
Applicable pipe diameter: 38mm ～ 9,000mm Round pipe and square pipe Applicable medium: full pipe, one-way flow, one-way gas, steam, and liquid Verabar with a viscosity not greater than 10 centipoise It is widely used for the measurement of various gases, liquids and vapors. The following are typical application media.
Gas / Liquid / Steam Natural Gas / Cooling Water / Saturated Steam Compressed Air / Boiler Water / Superheated Steam Gas / Demineralized Gas Hydrocarbons / Liquid Hydrocarbons
Flow instrument is one of the large-scale instruments in process automation instruments and devices.It is widely used in metallurgy, electricity, coal, chemical industry, petroleum, transportation, construction, light textile, food, medicine, agriculture, environmental protection and people's daily life. Various areas of the national economy are important tools for developing industrial and agricultural production, saving energy, improving product quality, improving economic efficiency and management levels, and occupy an important position in the national economy. Among the process automation instruments and devices, the flow meter has two major functions: as a detection instrument for the process automation control system and a total meter for measuring the quantity of materials. When fluid flows through the probe, a high-pressure distribution area is created in the front of the probe, and the pressure in the high-pressure distribution area is slightly higher than the static pressure of the pipeline. According to the principle of Bernoulli's equation, when the fluid flows through the probe, the speed increases, and a low-pressure distribution area is generated at the rear 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 created at the back of the probe, and vortices appear on both sides of the probe. The cross-sectional shape of the average velocity flow probe, the surface roughness, and the location of the low pressure pressure taking hole are the key factors that determine the performance of the probe. The stability and accuracy of the low-voltage signal play a decisive role in the accuracy and performance of the average speed probe. Verabar's average velocity flow probe can accurately detect the average differential pressure produced by the average velocity of the fluid. The Verabar average velocity flow probe has multiple pairs of pressure taking holes arranged according to certain criteria in the high and low pressure areas, making it possible to accurately measure the average flow velocity.
在投运前的工作和简单的维护做个大致的总结： The following is a general summary of the work and simple maintenance of Verabar flowmeters before commissioning:
1. Check the installation of the flow meter: After completing the installation of the Verabar flowmeter, it must be carefully inspected, and the welding must be firm, the direction is correct, and the pressure test has no leakage. 2. System warm-up: After the preparation for commissioning is completed, the measured medium fills the process pipeline, and Verabar flowmeter is temporarily closed. At this time, the balance valve of the three valve group should be opened, and the high pressure valve and low pressure valve should be closed. status. Power on the instrument and warm up for 15 minutes. 3. System operation: After the warm-up is completed, open the high-pressure valve and low-pressure valve of the three-valve group, fill the differential pressure transmitter with the measured medium, open the drain valve behind the differential pressure transmitter, and quickly discharge the dirty liquid or gas. Close the blowdown valve and then close the balance valve of the three-valve group. The transmitter will enter the measurement state and the flow totalizer will also enter the working state to display the medium flow in the pipeline. 4. Instrument calibration: Read the instructions of the intelligent flow totalizer carefully. According to the calculation book attached to the Verabar flowmeter, set the parameters in the intelligent flow totalizer correctly to ensure that the totalizer can correctly calculate and display the flow. If you are directly on the computer, you need to set the input data format and corresponding compensation methods in the computer. 5. Instrument wiring is correct: Verabar flowmeter, differential pressure transmitter, and flow totalizer constitute a measurement system. Rear can be put into operation.