Our Guide to Ultrasonic Flow Meters
An ultrasonic flow meter is a type of flow measurement technology that uses sound waves to measure the movement of liquids, gases or steam through a pipe. It is commonly used in industrial and utility applications where accurate, reliable and non-invasive measurement is required.
In this blog, we’ll provide a top-level guide to ultrasonic flow meters, including what they are, how they work, the different types available, the advantages of ultrasonic technology and common uses of ultrasonic flow meters.
What is an ultrasonic flow meter?
An ultrasonic flow meter is a device used to measure the flow rate of a medium moving through a pipe using ultrasonic sound signals.
Depending on the application and technology used, an ultrasonic flow meter can measure:
- Flow velocity
- Volumetric flow
- Mass flow
- Energy consumption
Ultrasonic flow meters can be used for a wide range of substances, including water, liquids, gases, sewage and wastewater, steam, thermal energy, compressed air and oxygen.
They are particularly useful where businesses need accurate flow data without needing to shut down operations in the process. This is especially true for clamp-on ultrasonic flow meters, which can be installed on the outside of a pipe.
How do ultrasonic flow meters work?
Ultrasonic flow meters use sound waves to calculate the speed of a medium moving through a pipe.
There are two main measurement principles associated with ultrasonic technology, transit-time and Doppler. We will explain what each of these are, below.
What is transit-time measurement?
Transit-time ultrasonic flow meters use two ultrasonic sensors, also known as transducers. These send sound signals both with and against the direction of flow.
When the medium is flowing, the signal travelling with the flow arrives slightly faster than the signal travelling against it. The meter measures this time difference and uses it to calculate the flow velocity. From there, the flow rate can be calculated.
This method is commonly used for cleaner liquids and gases where the sound signal can travel clearly through the medium.
What is Doppler measurement?
Doppler ultrasonic flow meters work slightly differently. They measure the change in frequency of a sound wave as it reflects off particles, bubbles or other moving elements within the flow.
This method can be useful in applications where the medium contains suspended solids or aeration, such as certain wastewater or slurry applications.
The right technology will depend on the medium being measured, pipe conditions, installation requirements and the level of accuracy needed.
What are the different types of ultrasonic flow meters available?
There are two main types of ultrasonic flow meters: clamp-on and in-line.
What is a clamp-on ultrasonic flow meter?
A clamp-on ultrasonic flow meter provides non-invasive flow measurement. At JWF we supply a range of permanent and portable FLEXIM clamp-on ultrasonic flow meters for industrial use across Scotland and the North of England.
These flow meters work across a wide range of conditions including:
- Pipe sizes from 10mm to 3000mm in diameter
- All pipe materials and wall thicknesses
- Low to very high flow velocities
- High temperature applications up to 400 degrees Celsius
- Hazardous area certification (ATEX Zone 2/FM Class 1, Division 2)
This means you can use the meter to measure flow across various points of your operation.
Instead of being installed inside the pipe, therefore requiring an interruption to processes, this is clamped on to the outside, with sensors sending sound signals through the pipe wall and the flowing fluid to calculate the measurements required.
Clamp-on ultrasonic flow meters can be used as either permanent or portable solutions. Portable options are particularly useful for surveys, audits, temporary measurement, troubleshooting or verification against an existing in-line flow meter.
They can help businesses gather flow data quickly and with minimal disruption.
What is an in-line ultrasonic flow meter?
An in-line ultrasonic flow meter is installed directly into the pipework. This means the meter becomes part of the process line.
In-line ultrasonic meters are often used where permanent measurement is required and where installation into the process is practical. They can provide accurate, continuous measurement and are commonly used in applications where the meter is specified as part of a wider system design.
While in-line meters can be highly effective, installation may require pipework modification and process downtime. For this reason, clamp-on technology is often preferred where non-invasive measurement is important.
What are the advantages of ultrasonic technology?
There are several advantages to using ultrasonic flow meter technology.
Non-invasive installation
One of the biggest benefits of clamp-on ultrasonic flow meters is that they can be installed on existing pipework without cutting them. This simplifies installation and makes the technology suitable for difficult or hazardous environments.
No interruption to process
Clamp-on ultrasonic meters are attached externally to pipework as mentioned earlier, which means zero pressure loss, and they can often be installed while the process remains live.
This is particularly valuable in sectors where shutdowns are costly, disruptive or difficult to schedule.
Suitable for a wide range of media
Ultrasonic flow meters can be used across a broad range of applications, from water and wastewater to gases, steam, compressed air and thermal energy.
Portable and permanent options
Ultrasonic technology is available as both portable and permanent measurement equipment. This gives businesses flexibility depending on whether they need long-term monitoring or short-term data collection.
At JWF, we provide FLEXIM ultrasonic flow meters for hire, this allows you to trial the technology before making a purchase or if you are looking to do a short-term flow survey.
Useful for verification and surveys
Portable clamp-on ultrasonic meters can be used to check performance against an existing in-line meter, carry out a flow survey or support a measurement audit.
This can help businesses identify problems within their process without committing to a permanent installation.
Supports energy and efficiency monitoring
Flow data is increasingly important for businesses looking to reduce energy consumption, improve process efficiency and support sustainability goals.
Ultrasonic meters can help provide the data needed to understand performance and make informed decisions.
What are some common applications of ultrasonic flow meters?
Ultrasonic flow meter applications span a wide range of industries and process environments. These include:
- Water and wastewater measurement
- Steam flow monitoring
- Gas flow measurement
- Compressed air measurement
- Thermal energy metering
- Process optimisation
- Verification against existing flow meters
- Temporary flow surveys
In water and wastewater applications, ultrasonic flow meters can help monitor consumption, leakage, network performance and process efficiency.
In industrial environments, they can support measurement of steam, gas, compressed air and thermal energy. This can help businesses better understand energy use, improve efficiency and identify potential issues.
How can JWF help?
No matter what industry you operate in, if you’re looking for advice on ultrasonic flow meter technologies you can speak to a member of the JWF team who would be happy to chat with you at length.
Our engineers can support with installation, commissioning, calibration, verification and flow surveys, helping customers understand what is happening within their processes. Our cloud-based data dashboard turns real-time measurements into meaningful insight, ensuring your operation is functioning as efficiently and effectively as possible.
Whether you need a permanent or temporary ultrasonic flow meter, or if you are looking for support in selecting the most suitable technology for your application, JWF can help.
To learn more about ultrasonic flow meters and the wider range of flow measurement technologies JWF offers, click here or get in touch with our team.