The correlation and electro-acoustic methods are often used to detect and locate leakages. But for some reasons certain leakages are not detectable with this methods. For the locating of e.g. very small leakages the application of tracergas is an alternative succesful method. For this method a certain tracergas is infilled under pressure into the pipe. If there is still water inside the pipe should be drained or blowed out.
How to use in practice
The leaky pipe is filled with inert gas (5 Vol.% hydrogen and 95 Vol.% nitrogen). This gas is commercially available and, in addition to the low price, has the advantage that it is neither combustible nor poisonous. Its use is thus completely safe. As the smallest element, hydrogen has the property of leaking from even the smallest pinhole. Because hydrogen is significantly lighter than air, it migrates upwards and is located above the leak by the bell probe. At the same time, hydrogen also passes through soil, flooring, concrete and screed.
As the smallest element, hydrogen has the property of leaking from even the smallest pinhole. Because hydrogen is significantly lighter than air, it migrates upwards and is located above the leak by the bell probe. At the same time, hydrogen also passes through soil, flooring, concrete and screed.
The location of the strongest concentration of hydrogen is easily determined using a concentration indicator on the display of the measurement device. Depending on the actual concetration and situation it is possible to use different scales and sensors. One scale is for very low concentrations (0 … 1.000 ppm H2) and one is for pinpointing (0 … 5% H2).