Abstract: A monitor for detecting overheating of a critical component in a combustion turbine is provided. The monitor, when used in conjunction with a closed-loop cooling system, comprises a coating comprising an indicator material having an activation temperature. The coating is situated on the internal cooling passages of the critical component. The monitor further comprises a sensor connected to an outlet conduit of the cooling system for determining the amount of degradation of indicator material by monitoring the cooling fluid flowing through the outlet conduit. Embodiments further comprising “sniffer” tubes for use with open-loop air cooling systems also are provided. In alternative embodiments, auxiliary cooling systems for supplying auxiliary cooling to critical components at certain activation temperatures also are provided.

Abstract: A method of bonding together at least two long, metal alloy segments, of turbine components, such as turbine blade segments (18, 19, 20 and 21) by: putting a melting point depressant between the segments at bond planes (34) between contracting segments; forming a heated zone across the segments and a heated front (32); where melt pools (36) form in a molten zone (38) at the heated front which front (32), pools (36) and zone (38) continuously move and pass along the bond planes (34); where crystal re-growth (35) occurs along the bonding planes to form bonds (34) between the individual segments (18, 19, 20 and 21) behind the moving molten zone (38).

Abstract: A monitor for detecting overheating of a critical component in a combustion turbine is provided. The monitor, when used in conjunction with a closed-loop cooling system, comprises a coating comprising an indicator material having an activation temperature. The coating is situated on the internal cooling passages of the critical component. The monitor further comprises a sensor connected to an outlet conduit of the cooling system for determining the amount of degradation of indicator material by monitoring the cooling fluid flowing through the outlet conduit. Embodiments further comprising "sniffer" tubes for use with open-loop air cooling systems also are provided.

Abstract: A nondestructive inspection device and a method of monitoring a defective condition in a rotating member of a combustion turbine engine using a nondestructive inspection device is presented. The nondestructive inspection device includes a sensor for monitoring the rotating member and a holder assembly for positioning the sensor near the rotating member without disassembling the combustion turbine engine. The holder assembly is capable of interchangeably positioning either an ultrasound transducer or an eddy current sensor. Signals indicative of the monitored condition are recorded and compared to a signal representation generated from a reference standard having a known defect so that a defective condition can be ascertained. The location of a defective condition is ascertained by using a magnetic belt having a plurality of magnets wrapped around the rotating member and an additional sensor to detect the magnets as they rotate.

Abstract: The present invention provides an eddy current sensing device capable of in-situ operation within a high temperature and high vibration environment of a combustion turbine engine. The eddy current sensing device is preferably utilized in an eddy current sensing system for monitoring crack formation and displacement of rotating members of the combustion turbine engine. The method according to the present invention provides inducing eddy currents in the rotating member, detecting the eddy currents, providing a signal indicative of the detected eddy currents, filtering the signal based on the condition to be monitored and evaluating the filtered signal to determine whether the condition, such as the formation of a crack in the surface of the rotating member exists, and if so, determining whether the condition is critical or routine.