Overview

There are many types of failures associated with a gas turbine, since these units are very complex in their overall makeup. Gas turbines are used in many different applications, from driving compressors and pumps, in process plants and offshore platforms, to generating power as peaking units, and as part of large combined cycle power plants. The gas turbines in the process and offshore platforms are usually below 30 MW and are operated 24 hours a day, 365 days of the year. The peaking units operate about 1300 to 1500 hours a year and about 5 to 12 hours a day. Combined cycle power plants were originally designed to operate as base-loaded units; however, in 2005 most of these units operated five days a week and during the day the plants were cycled from about 40 100% power load. Most operators and OEMs work on an equivalent hour basis, which takes into account the number of starts, and the percent load and time at which they are operated. The gas turbine failures range from control system problems, which are the most frequent although the downtime accompanying these failures usually is the smallest, averaging a few hours; the problems with combustors, rotors, and blade failures are less frequent but the downtime and costs accompanying those failures could extend to several weeks, and several million dollars in costs. The hot section failures far outnumber the problems in the compressor due to the high temperatures associated with the hot section, however a blade failure...