What are the Main Benefits of Ultrasonic Flow Meters over Inline Flow Meters? Flow Meters Explained

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Coltraco Ultrasonics is the global leader in our fields of contents monitoring of gaseous extinguishing systems and watertight/airtight integrity monitoring. We pride ourselves on the quality, reliability, and accuracy of our instruments, all made in the United Kingdom.

Our range of Ultrasonic flow meters, the Portasonic® 2.FL0 and Permaflow®, supported by the Portasonic® Calculator handheld tablet for calculating pipe pressure from flow meter measurements are:

  1. Accuracy and reliability tested and calibrated at an ISO 17025 certified laboratory for flow measurement in the UK, meeting accuracies of +/- 0.5% of the true flow rate.
  2. Built with exceptional quality materials, including a special composite material to optimise ultrasound transmission, and remain competitively priced in the market worldwide through our unique R&D position.
  3. Fitted with a built-in oscilloscope for signal diagnostics that assists you in performing a reliable measurement as part of the setting-up process.
  4. Delivered with the guarantee of technical support, advice and assistance with your application being available throughout the lifetime of the unit

Ultrasonic flow meters use two ultrasonic sensors, clamped on to the outside of the pipe at a pre-determined distance apart. Ultrasonic signal travels between the transmitters through the pipe wall and the fluid within the pipe. If the fluid is flowing, then it takes slightly longer for the ultrasound to travel against the flow (upstream time T_up) than with the flow (downstream time T_down). This very small time difference (T_up – T_down), usually only tens of nanoseconds, is measured by the ultrasonic flow meter and is directly proportional to the flow velocity (V) of the fluid.

By comparison, inline flow meters, such as positive displacement flow meters and turbine flow meters, are invasively fitted solely to a specific range of pipe sizes, where the pressure of the pipework has been previously taken into account, so as to not damage the inline flow meter.Ultrasonic flow meters are better-faster-cheaper in comparison to traditional inline flow meters:

  • Better: Ultrasonic flow meters are non-invasive, non-destructive, and non-disruptive. As there is no contact with the fluid being measured, there is no risk of pressure drop throughout your pipe network. In addition, ultrasonic flow meters can be retrofitted to a broad range of pipe sizes.
  • Faster: The non-disruptive, non-invasive nature of ultrasonic flow meters, with no installation costs such as drilling into pipes, allows our ultrasonic flow meters to often be in situ more quickly than an inline flow meter, with no downtime to the pipe network.
  • Cheaper: The fluid being measured cannot damage ultrasonic flow meters. This could contribute to a longer lifespan and lower maintenance costs compared to inline flow meters which are at risk of being damaged by their contact to pressurised flowing fluid.

Our ultrasonic flow meters are not only highly capable of performing accurate and reliable water flow measurement as water meters, but work on a wide variety of different fluids. Furthermore, our Portasonic® Calculator, due to our detailed understanding of the properties of over 19 different fluids and 23 different common pipe materials, is the first instrument capable of determining the internal pressure within pipes to +/- 5% accuracy.

Alongside our Portasonic® 2.FL0 ultrasonic flow meter, one of the world’s leading non-invasive flow meters, the Portasonic® Calculator allows its user to perform a wide variety of maintenance

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Come say hello at our Technical Laboratory.

Coltraco Ultrasonics
NETPark Research Institute
Joseph Swan Road
TS21 3FB

United Kingdom


Monday - Friday (excluding bank holidays) from 8:30am to 6:00pm, UK.

Tel (Sales & HQ): +44 20 7629 8475
Tel (Technical): +44 1740 618 240