Abstract:For the particularity of turbine blade test, such as the shape irregularity, test space limitation, low test ratio and few test methods, etc., this paper carried out the eddy current testing experiments using penbased single probe and fingertip single probe. The simulating crack comparison tests showed that both of the two kinds of probes could effectively detect defects, the phasor amplitude sensitivity of easyoperating fingertip single probe is about 50% lower than the penbased single probe, and the detection of edge or lacing hole need to develop a special probe or tooling in order to ensure the smooth moving of probe. Field application indicated that the eddy current testing have certain advantages for the steam turbine blade body and its shroud, which is an effective supplement to conventional detection methods. 

Keywords:steam turbine, blade, eddy current testing, probe, shroud