The Reliability and Limitations of Ultrasonic Flow Meters

Subscribe for the latest industry news, technologies and resources.

We care about your data in our privacy policy.

Ultrasonic flow meters are widely utilised in various industries due to their non-intrusive measurement capabilities and easy installation. However, understanding the reliability of these devices and their limitations is crucial. In this article, we will delve into the topic of ultrasonic flow meters, exploring their reliability and discussing the limitations associated with their usage.

The Advantages of Ultrasonic Flow Meters

Ultrasonic flow meters offer several advantages that contribute to their overall reliability. These advantages include:

Non-intrusive Measurement

Ultrasonic flow meters do not require cutting into pipes or interrupting the flow of the medium being measured. This non-intrusive nature minimises the risk of leaks or system disruptions, ensuring continuous and reliable operation.

Versatility in Applications

Ultrasonic flow meters are unaffected by the measured fluid’s conductivity, pressure, or temperature. This versatility makes them suitable for various applications and contributes to their reliability in various industries.

Accuracy and Precise Measurement

Ultrasonic flow meters employ two primary methods for flow measurement: transit-time and Doppler. These methods provide accurate and precise measurement capabilities for both clear fluids and those containing particles or bubbles.

Minimal Maintenance

The absence of moving parts in ultrasonic flow meters eliminates the need for regular maintenance and reduces the risk of mechanical failure. This inherent durability enhances their long-term reliability and cost-effectiveness.

Limitations of Ultrasonic Flow Meters

While ultrasonic flow meters offer numerous advantages, they must be aware of their limitations to ensure reliable usage. The limitations include the following:

Fully Filled Pipe Requirement

Ultrasonic flow meters require a fully filled pipe to operate accurately. The presence of air or gas bubbles in the fluid can affect measurement accuracy, particularly in transit-time meters. Alternative flow metering technologies may be more suitable in applications where a fully filled pipe cannot be guaranteed.

Influence of Pipe Material and Thickness

The type of pipe material and its thickness can impact the transmission of ultrasonic signals. Certain materials with high absorption or attenuation properties can weaken the signal and compromise measurement accuracy. The compatibility of the ultrasonic flow meter with specific pipe materials and thicknesses is crucial for reliable operation.

Limitations in Measuring Low Flow Rates

Ultrasonic flow meters may encounter challenges when measuring low flow rates accurately. The minimum flow rate required for reliable operation varies depending on the meter’s design and application. Understanding the application’s minimum and maximum flow rate requirements ensures the ultrasonic flow meter’s reliability.

Impurities and Interference

Fluids containing high impurities, such as particulates or bubbles, can interfere with the ultrasonic signal, leading to inaccurate measurements. In such cases, alternative metering technologies or additional filtration systems may be necessary to maintain reliable operation.

Contact Coltraco Ultrasonics Today

Ultrasonic flow meters provide reliable and accurate flow measurement capabilities in various industrial applications. Their non-intrusive nature, adaptability to different flow conditions, and minimal maintenance requirements contribute to their popularity. 

However, it is essential to understand their limitations, including the fully filled pipe requirement, the influence of pipe material and thickness, limitations in measuring low flow rates, and challenges with impurities. 

By considering these limitations and consulting with manufacturers and industry experts, engineers and technicians can make informed decisions to ensure the reliable operation of ultrasonic flow meters. 

Get in touch

You can reach us anytime via phone or email, we aim to respond to all enquiries within 24 hours (excluding weekends and bank holidays)


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