Leak detection in a real transmission main through transient tests: deeds and misdeeds

This paper concerns the use of Transient Test‐Based Techniques (TTBTs) for fault detection in a long transmission main. It reports the results of two series of transient tests executed in a real and operating pipe system. Because of the complexity of the investigated pipeline that includes several stubs, different pressure wave generators were used at both the end sections. Precisely, transients were caused by a pump shut‐down and the Portable Pressure Wave Maker device. The analysis of the results shows that, according to the characteristics of the transient tests and the investigated system, only a part of the system can be explored properly from a given generation point. The proposed test procedure allows overcoming the negative effect of a change in the initial and boundary conditions. In fact, contrary to laboratory, in a real system, it is quite impossible to repeat tests in the same flow conditions. The success of the survey—with two leaks detected with a good precision—confirms the potential of the TTBTs for fault detection in real systems.