RS Hydro supply the latest in ultrasonic flow meter technology: portable flow meters that can measure liquids up to 250ºC and be used in complex heat metering projects.
Ultrasonic Flowmeters
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Easily installed clamp on flow meter without process interruption;
- Minimal installation, low cost and no pressure loss;
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Non invasive flow measurement of water and almost any liquid including de-mineralised water
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Pipe Size range: 10-7000mm diameter, most pipe materials and linings;
- Ultrasonic flow meters suitable for hazardous areas;
- Heat Meter functionality standard on some models
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Portable, spool-piece, wetted and dry transducer versions available
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Process temperatures of -260°C to +260°C
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Optional Ultrasonic Thickness Gauge also available.
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Multiple process analogue and digital inputs (4-20mA, relays, temp, pressure for any parameter)
- Integral datalogger
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Models with integral data logger
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The non-contact ultrasonic flow meter is a non-invasive flow meter available in two formats: transit time and doppler. Both technologies feature clamp on designs with transducer arrangements that can detect in-situ flowrates from outside the pipework, without any interruption to flow or process. Transit time flow meters, or also known as 'time of flight' meters are mainly consigned to the measurement of clean liquids, although many flow measurement devices have a maximum tolerance of 5% solids. The principle behind this type of non-intrusive clamp-on (strap on) flow meter is that accoustic waves with a frequency of >20kHz are emitted from one transducer to the other side of the pipe back to the opposite transducer requires less time than when travelling in the opposite direction. The differential transit time of the synchronised signals is proportional to the flow rate of the fluid.
Advantages of Clamp-On Flowmeters
- Non-invasive liquid flow monitoring
- Measurement of non-conductive fluids
- Easily installed clamp-on sensors with no interruption to flow
- Wide range of pipe materials and sizes: 12.7-7600mm
- Process temperatures from -40°C to 200 °C
- Integrated wall thickness measurement
Comparison of Ultrasonic vs Other Types of Meter
| Type of Meter | Advantages |
| Coriolis |
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| Vortex |
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| Magnetic |
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DP |
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Turbine |
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Which Ultrasonic Flowmeter ?
| Manufacturer/Model | Verdict |
| Katronic KAT220 | 75% |
| Micronics Portaflow 300 | 75% |
| Polysonics DCT7088 | 60% |
| Panametrics PT878 | 90% |
The above verdicts are based on RS Hydro's own experience and that of its customers.
GE Panametrics PT878
The GE Panametrics PT868 and PT878 flow meters are designed to withstand rugged use in industrial applications. With superior diagnostics, functionality and accuracy this flow meter is regarded as leading edge technology. The PT878 utilises an acoustic signal-coding technique to make accurate measurements in flows containing gas bubbles or entrained solids. We would recommend this flow meter to professionals who want the most from a portable ultrasonic flow meter. This meter has two external inputs which makes it ideal for a heat metering survey.
Micronics Portaflow 300
The Micronics Portaflow 300 clamp on flow meter is aimed at those who want a compromise between performance and price. This portable flow meter is designed to be used by anyone who has not used a non-invasive flow meter before. With up to 24 hours battery life this flow meter does last longer than any other. However, this flow meter does not accept external outputs eg for heat metering purposes or pump testing.
Katronic KAT220
The KAT220 ultrasonic flow meter is regarded as a good clamp on flow meter offering the ability to measure two flows with one transmitter and external inputs. However, this flow meter does lack the display and diagnostics facilities of the GE Panametrics PT878.
Applications for Ultrsonic Flow monitoring
Portable ultrasonic flow meters can measure almost all light homogeneous fluids including water, wastewater (<5% solids) and hydrocarbons. The basic requirement is that the fluid can conduct ultrasound and have an acceptable axis-symmetrical flow. Click here to see the many fluids that ultrasonic devices can measure.
Typical applications include:
- Water distribution flowmetering
- Leak Detection
- Wastewater flow-metering
- Building Services
- Inspection of fixed installation meters
- Power/Energy Management
- Chemical / Pharmaceutical
- Petro-Chemical
- Pump inspection
- Food/Hygienic flow-monitoring
- Steel
- Light Industrial
- Survey work
Flowmeter Specifications
Although specifications are different between the various manufacturers, the following is intended as a guideline to their performance and specification.
| Flow Range | 0.01-20m/sec (Bi-Directional) |
| Accuracy | ±0.5-3% of reading |
| Repeatability | Typically ±0.5% |
| Pipe Size | 12.7-7600mm |
Operating Temperature |
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| Transducers | -40°C to +200°C |
| Transmitter | -10°C to 50°C |
| Datalogging | Typically>100,000 data points, time stamped |
| Output | 4-20mA, pulse |
| Power | Built-in battery with external 12v input, 8-36 hours operation |
| Dimensions | Typically 250 x 150 x 40mm |
| Weight (Control Unit) | Typically 3-5lbs (1-2kg) |
Technical Notes
In order to obtain the optimum accuracy from a portable flow meter, the following conditions must apply:
| Requirement | |
| Location | At least 10 diameters of straight-length pipework must exist upstream of the measurement point, and 5D downstream. Ideally these distances should be as large as possible. |
| Wall Thickness | For optimum accuracy, the pipe wall thickness should also be measured. Some meters are supplied with ultrasonic wall thickness gauge |
| Liquid Medium | It is essential that the type of fluid is known. Also that there are no air bubbles and that the solid content does not exceed 5%. |
Pipe Condition |
The pipe wall exterior should be free from dirt, paint or corrosion. For optimum accuracy the interior wall should also be free from deposits or corrosion. |
