Cracking and leakage, not repairable by welding, was found in premix piping of heavy-duty gas turbine engine for power plant applications. The subject laboratory specimen, a pipe section cut out on site and received at the investigating laboratory, failed by transgranular stress corrosion cracking (SCC). The stress corrosion cracking has probably been induced by chlorides (halide-induced stress corrosion cracking). Chlorine peaks were found in EDS spectra acquired on the inner pipe wall surfaces. However, it cannot completely be ruled out that those were artifacts caused by handling, cleaning, and cutting. The cracking is located adjacent to welds.