What is a non-contact flow meter?
Non-contact flow meter is a kind of flow metering device that does not need to insert, no pipe penetration or cut any mechanical parts through the pipe or extend into the flow system to accurately measure the liquid flow rate in the closed pipe.
Non-contact sensor can be installed on the outer wall of the pipeline to achieve flow measurement without pipe or flow interruption, and there is no pressure loss for its non intrusive flow meter sensor.
Clamp on ultrasonic flowmeter realizes the non-contact measurement of the liquid flow rate. Only by attach the non intrusive sensor on the pipe outer wall to complete the flow measurement.
Liquid can be measured by non contact flow meter
Hot water, cold water, portable water, drinking water, waste water, sea water, tap water, diesel; demineralised water, demi water, deionised water, pure water, cooling water, distilled water, boiling water flow rate and flow velocity flow meter.
Non-contact flow meter technology & ultrasonic flow meter types
Non-contact flow meter uses ultrasonic transit time technology to measure the volume flow by detecting the effect of the ultrasonic beam (or ultrasonic pulse) when the fluid is flowing.
When the sound wave propagates in the fluid, the speed of the sound wave will increase in the downstream direction and decrease in the countercurrent direction. The same propagation distance will have different propagation times. Use the difference between the propagation velocity and the flow velocity of the fluid to be measured to obtain the flow velocity, which is called the transit time flow meter.
Ultrasonic flow meter types
According to the ultrasonic liquid flow meter, there are: transit time flow meter; Doppler flow meter; beam shift method; noise method.
According to the structure of ultrasonic flow meter: panel-mounted, wall-mounted, integrated, portable flow meters, handheld flow meters, alignment rail transducers, clamp-on flow meter, insertion ultrasonic flow meters , etc.;
Non-contact flow meter advantages
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Non-contact liquid flow meter does not need to stop the flow and cut off the pipe to install the sensor, only by clamping the flow sensor on the outside of the pipeline, it is suitable for the evaluation and determination of the flow condition of the pipe network.
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For flow rate measurement without flow obstruction, there is no additional pressure loss.
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The flow meter coefficient can be calculated from the actual measurement of the geometrical dimensions of the pipeline and sound channel, no laboratory flow calibration required;
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Flow meters for large pipelines -It is suitable for large round pipes and rectangular pipes, and is not limited by pipe dia size, such as can be used as 4 inch non contact flow meter, 8 inch non intrusive flow meters, 10 inch,12 inch non contact flow transmitter, 14”,16”,18”20”,24 inch clamp on ultrasonic flow meters;
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Cheap non-contact flowmeter; even for large pipeline flow meters, the non contact flow meters price is still very competitive and low cost. Most of the non-contact ultrasonic flowmeters made in China flow meter factory around US$400.
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Ultrasonic liquid flow meter can measure non-conductive liquids and is a supplement to electromagnetic flowmeters also as unobstructed flow measurement.
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By adding a low cost temperature sensor to realize economical heat flow sensor for enhanced energy management, non contact flow meter use as energy flow meter as well, with thermal energy/BTU capability
Disadvantages of non contact flow sensor
Transit time ultrasonic flow meter can only be used to clean liquids and cannot measure liquids with suspended particles and bubbles exceeding a certain range; Doppler ultrasonic flow meter can only be used to measure liquids that contain a certain phase, but the Doppler ultrasonic flow meter has poor accuracy;
Non contact flow meters with clamp on transducers cannot be used for pipelines with thick lining or thick fouling, stainless steel 316 or pipelines with severe corrosion.
Has poor performance for pipelines smaller than DN32mm
Specifications of none contact flow meter
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Good stability and high accuracy: Linearity is better than 0.5%, repeatability is better than 0.2%, measurement accuracy is better than ±1%
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Wide measuring range, various flow probes options: Different types of ultrasonic flow sensors can be used to measure the flow rate of pipes with a diameter of DN32 ~ DN6000mm
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Non contact flow detects velocity range: -32m/s~+32m/s;
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Small and light non contact flow meters: easy for transportation and carry on, also easy to install the clamp on transducers;
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IP68 high waterproof protection level;
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Digital clamp on transmitters to have digital display to show liquid flow rate and totalized flow information;
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With keys for easy configurations and easy setting;
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Flow transmitters have strong anti interference from frequency converters, TV towers, high-voltage lines, etc.
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Data logger function: automatically memorize the cumulative flow of the previous 64 days, 64 months, and 5 years,
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Fast and easy networking and long transmission distance:
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RS-485 MODBUS transmission can max have distance 1000 meters, and the networking is very convenient and fast. This transmission has strong anti-interference ability and solves the problems of high cost, poor anti-interference ability.
