Page 465 - Practical Machinery Management for Process Plants Major Process Equipment Maintenance and Repair

Chapter 9

Gas lhrbine Maintenance Philosophy and Obiectlver

There are probably as many different approaches to gas turbine main-
tenance as there are users. Each philosophy must be the right one for a
given user, in a given location, for a given type of gas turbine. The most
important thing is to decide on an approach or philosophy that will opti-
mize the resources of the user's company and provide an acceptable level
of risk for the business in which the gas turbine is applied. This decision
should be made as early as possible for it will affect which type of turbine
is right for the application. Once a gas turbine is purchased the available
options in maintenance practice are narrowed considerably.
It is difficult to approach gas turbine maintenance as a single subject
because there are two distinct groups of turbines which require greatly
different approaches. These are the heavy duty indwrn'uls and the uir-
cru. derivatives. Primarily we will be discussing the maintenance of the
heavy duty industrial turbines. (Figure 9-1.) Aircraft derivative units, as the
name suggests, are derived from turbines designed for aircraft use and thus
their maintenance has to a great extent followed the practices of the aircraft
industry.
Proper selection of a gas turbine should focus on the relative strengths
and weaknesses of each design.' The jet engine (Figure 9-2) was designed
to be a very compact, lightweight powerplant for aircraft propulsion and
is far superior to any other prime mover for this application. In the
design of any component, or system of components, it is important to

*Compiled by Dean H. Jacobson, Exxon Co.

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