Ultra sonic leak detectors utilize the principle that pressurized gases or liquids escaping through a small orifice generate high-frequency sound waves, typically in the range of 20 kHz to 100 kHz, which is beyond the human hearing range. These turbulent flows produce distinct ultrasonic signatures.
The equipment consists of a sensor, often a specialized microphone or transducer, capable of detecting these high-frequency sound waves. As the detector is moved near a potential leak, the sensor picks up these ultrasonic emissions. Sophisticated internal circuitry then amplifies and processes these signals, often using a technique called “heterodyning.” This process converts the high-frequency sound down to an audible range that can be heard through headphones worn by the operator.
Many ultrasonic leak detectors also feature visual indicators, such as LED bars or digital displays, that show the intensity of the ultrasonic sound. As the operator moves closer to the source of the leak, the audible sound becomes louder, and the visual indicators show a stronger signal, allowing for precise pinpointing of the leak’s location. Some advanced units even incorporate spectral analysis or acoustic imaging to further differentiate leak sounds from background noise and provide a visual representation of the sound source. This technology enables the detection of even minute leaks in various pressurized systems, including compressed air, gas lines, vacuum systems, and refrigeration units, often before they become significant problems.