Industrial transformers are widely used and can be extremely large. When constructing or repairing a transformer, it is essential to check that it is completely leak-proof. This is crucial because transformers are filled with mineral oil, which serves to cool the unit, provide electrical insulation and protect against oxidation.
If a leak is detected during filling, all the oil must be drained again before the problem can be resolved. This results in significant losses of time and money.
At present, transformers are tested by filling them with dry air to an overpressure of 200–300 mbar. This pressure is maintained for several hours to check for any pressure drop, which indicates leaks. A higher test pressure is not possible due to the transformer’s construction. Components such as pressure relief valves, cooling fins and certain joints cannot withstand higher pressures. If a pressure drop is detected, a soapy water solution is used to locate leaks. All joints and connections are checked manually. The formation of air bubbles indicates a leak.
This method is:
It is therefore the case that leaks only become apparent once the transformer has been filled with oil and is operational.
CS INSTRUMENTS has over 20 years’ experience in ultrasonic leak detection. This technology makes it possible to detect leaks without the system needing to be on overpressure.
A compact ultrasonic tone generator is placed inside the transformer, requiring only an opening of 8 cm in diameter. Bespoke solutions are available for smaller openings. The sound source emits a powerful ultrasonic signal in multiple directions, which propagates throughout the entire transformer. An ultrasonic leak detector can then be used on the outside of the transformer to easily determine where leaks are located. Where a leak is present, the ultrasonic signal escapes and is detected by the leak detector responding to the ultrasonic tone.
Advantages of this method:
Thanks to this approach, a complete transformer can be checked for leak-tightness quickly and reliably, with a significant reduction in working hours and the risk of missed leaks.
Detects multiple leakages simultaneously with globally unique Power Beam Forming. 4th generation technology - also suitable for other gases. Helps to locate and repair leaks - including cost estimation and ISO 50001 documentation.
uses 30 MEMS microphones for the Calculation and visualisation of the ultrasound image. The device also makes inaudible ultrasound audible.
Create an ISO 50001 report with leak detector LD 500 with camera and leakage calculation (l/min and costs in €).