This Inspection and Maintenance Guide outlines the activities that constitute a good maintenance philosophy for hydrogenerators in order to maximize unit availability and reliability. It is concerned primarily with the generator itself and is restricted to those components on the generator side of the main shaft coupling. As such, detailed emphasis is placed on the electrical elements and their inspection and maintenance however the major generator mechanical components are also included. Major elements are covered in separate sections within the guide commencing with rotating components and progressing to the stationary parts.
The guide primarily deals with vertical units as these units form the vast bulk of the fleet and capacity of hydrogenerators worldwide. Where appropriate, some discussion on procedures specific to older horizontal units is provided, however, much of the document is adaptable to any machine.
In an effort to provide background to the inspection process, the guide provides background information and comment on the design and purpose of many portions of a typical machine. A typical section includes:
– Design and design evolution
– Access requirements
– Activities prior to shutdown
– Inspection tools
– Inspection points and activities
– Maintenance frequency
The guide makes suggestions regarding inspection and maintenance activities and frequency however, it is appreciated that most organizations adapt these to their individual machines based on historical operation and features unique to their equipment or its operation. The depth of inspection and maintenance to be performed may be governed by the age of the machine or some of its major components, utilization factor, and energy and capacity values and so on. The goal here is to provide as much detail as is reasonably possible to permit appropriate customization while ensuring that no important elements have been overlooked.
Included with the Guide is a set of detailed inspection sheets on which to record all inspected elements and note activities carried out. These can provide a means to record information from one inspection cycle to the next and assist in the complete and clear transfer of knowledge and history to future maintenance personnel.
Keywords: Hydrogenerator, generator, inspection, maintenance