Page 476 - Practical Machinery Management for Process Plants Major Process Equipment Maintenance and Repair

Gas Turbines 453

Figure 9-5. Computerized machinery monitoring system (courtesy Zonic Corp.).

formance of the compressor with the turbine section for a given output
speed and exhaust gas temperature.

lnspectionlOverhaullRepair

This section deals primarily with one of the two basic types of mainte-
nance practiced on gas turbines, that is scheduled maintenance. The other
type, unscheduled maintenance, is the type which we seek to avoid, or at
least minimize. Unscheduled gas turbine maintenance in a process plant
is always extremely expensive and when carried out well is characterized
by rapid identification of the problem and implementation of the solution.
Time is not usually spent thinking about “what else should be done.” It
was once said that, “emergency shutdowns lead to hasty decisions which
in turn lead to costly mistakes.”
Scheduled maintenance in its broadest sense includes many of the con-
cepts dealt with earlier in this chapter. Scheduled maintenance is a contin-
uous activity which incorporates the condition monitoring program, rou-
tine inspections by operating personnel who identify problems which can