Vibration Monitoring and Diagnostic Instrumentation for Industrial and Marine Gas Turbines

The application of vibration monitoring and diagnostic instrumentation to industrial and marine gas turbines requires some important special considerations. An initially important consideration is the proper selection and location of vibration transducers. Next, a full-time monitoring system must be selected to afford the machine complete protection against failures caused by excessive vibration. And finally, diagnostic instruments must be selected on the basis of required data for malfunction diagnosis, past machine performance history, and current operating conditions of the machine. There are a number of vibration instrument considerations peculiar to gas turbines in general, as opposed to other types of rotating machinery such as steam turbines, compressors, gears, etc. These considerations can be classified as: (a) temperature extremes, (b) environmental extremes, (c) machine casing flexibility, or stiffness, as compared to the rotor. Both the heavy-duty industrial type and the lightweight, or aircraft derivative, type of gas turbine are widely used. A distinction will not be made between these types since most special considerations apply equally well to all gas turbines.