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.
的低压孔实现本质防堵一般情况下，灰尘、沙子和颗粒在涡街力的作用下，集中在探头的后部。 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.
The DEC-HLV Verabar flowmeter uses an engineering structure design that fully complies with aerodynamic principles, and is a sensor element that has achieved unparalleled levels of accuracy, efficiency, and reliability.
1, Verabar flowmeter uses
Verabar flowmeters are suitable for high-precision flow measurement of gases, liquids and vapors. 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, non-pulsating differential pressure signal2, the design characteristics of the probe, the probe's cross-sectional shape of the probe can produce accurate pressure distribution, fixed fluid separation points; The low-pressure pressure taking hole before the fluid 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, which makes the average speed tube flow probe anti-clogging level reach Unprecedented height. 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, and detours, and no longer enters the low pressure hole of the Verabar flowmeter in the elbow to achieve essential anti-blocking. In general, dust, sand and particles are in the vortex street. The force is concentrated on the back of the probe. 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. Advantages of the probe ● It can measure a variety of media and has a wide range of applications ● High accuracy and large range ratio ● The probe's pressure hole is essentially anti-blocking ● The measurement signal is stable and the fluctuation is small ● The permanent pressure loss of the pipeline is low ● The unique high-strength bullet Head-shaped single-chip dual-cavity structure ● Low installation cost and basically maintenance-free ● Can be installed and repaired online
5. Characteristics of Verabar averaging tube flow sensor ● Stable signal Verabar's low-pressure pressure taking holes are located on the back of the probe side, between the fluid and the probe separation point, and away from the vortex fluctuation area.
● Excellent long-term high-precision Verabar can guarantee long-term stability of accuracy, because:
⑴. It is not affected by abrasion, dirt and oil.
⑵. There are no moving parts in the structure.
⑶. The occurrence of blockage is excluded from the design. At the front of the probe, a high static pressure area surrounds the probe so that the high-pressure pressure taking hole will not be blocked. The most important thing is that the low-pressure holes are taken at the back two sides of the probe side, and the fluid is swept across the surface, which protects the low-pressure holes from being swept, and other probes are easily blocked because their low-pressure pressure holes are collected by impurities. Low voltage fluctuation area.
● Lowest installation cost ⑴. It only needs a few inches of line welding, and the installation is very simple and fast.
⑵. Apply special tools to achieve online installation with pressure.
⑶. All valves and interfaces of various instruments need only simple assembly, which requires very low assembly costs.
● Very low operating cost. It is a non-constricting design. As a plug-in flow probe, Verabar has the lowest operating cost.
只产生非常低的永久性压力损耗，典型的少于0.7KPa威. Verabar flowmeters only produce very low permanent pressure losses, typically less than 0.7KPa
⑶. The permanent pressure loss generated by an orifice plate element exceeds 14KPa
⑷. Compared with the orifice plate, Verabar's energy loss is reduced by 95%.
● The continuous operation of Verabar basically eliminates the possibility of clogging, but in the following cases, Verabar still needs to pay attention to the clogging:
⑴. When the impulse tube leaks and the high pressure balance area of the probe is damaged, particles with smaller diameters in the impurities may enter the pressure taking hole.
⑵. When the pipeline is stopped, due to the Brownian motion of the molecules, small particles of impurities may enter the pressure taking hole.
⑶. The system frequently starts and stops. At the moment when the high-pressure area is formed, small particles of impurities may enter the pressure taking hole. Over time, the probe may be blocked.
⑷. The medium contains a large amount of tar, algae, or contains fibrous substances, which may also cause the probe to be blocked.
6, the application of new technology unique design of valve joints with valve ... New design concept provides a new concept, built-in instrument stop valve at the connector of the instrument
1. Make installation and maintenance easier.
2. Reduce the number of assembly parts and reduce the cost of hardware connection.
Quick installation system Quick insertion and removal ● Sealed drive system can avoid damage to components ● Can be applied to the installation of multiple probes, all installed within less than 1 hour / Superheated steam gas / Demineralized gas hydrocarbon / Liquid hydrocarbon hot air / Cryogenic liquid generator gas / Heat transfer liquid
主要技术指标: Main technical indicators of Verabar flowmeter :
1. Performance index of Verabar flow 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, unidirectional flow, unidirectional gas, steam and liquid Verabar with a viscosity of not more than 10 centipoise It is widely used for the measurement of various gases, liquids and vapors. The following are typical application media.