Ultrasonic Analysis - Leak Detection

Applied Diagnostics Ltd - Precision with Pride

This technology detects Ultrasonic emissions in the 20 kHz to 1 MHz frequency range. These emissions are normally beyond the human hearing range, but a technique known as Heterodyning converts the signal into an audible signal. An instantaneous decibel reading is also measured to assist in the diagnosis of problems. Ultrasonic signals are detected using either an Airborne Sensor or a Contact Sensor depending upon the application:

Airborne emissions are generated when Air, Steam or Gas leaks from a pressurised line. It can also detect leaks in Air Handling Units or Extraction Vents. The signal is easily interpreted as a rushing sound and can pin point the exact location of the leak. Considerable savings can be made by reducing leaks in your plant.

We utilise ultrasonic analysis in a number of applications:


The airborne sensor can also be used to detect Electrical Arcing and Corona discharge, both of which can be detected in High Voltage Switchyards. Lower voltage applications such as control and distribution panels can also be easily checked.

Ultrasonic Analysis can also monitor the following areas, although we tend to use the previously covered technologies:


A contact sensor is used to check if a valve is fully closed or fully open - partially opened or leaking valves generate fluid turbulence that can create ultrasonic emissions. Usually a temperature reading is collected from the Inlet and Outlet sides of the valves to assist with the diagnosis.


As with valve monitoring ultrasonic signals are detected using a contact probe. These are typically generated if a trap fails allowing live steam to pass into the condensate return line. Considerable savings can be made by reducing steam loss in your plant.


Ultrasonic emissions are produced when moving mechanical parts come in contact with each other. The use of an ultrasonic contact probe enables a quick check to be made of the mechanical condition and lubrication level. This is suitable for applications where data collection time needs to be kept to a minimum e.g. monitoring a large numbers of slow speed bearings.