Maintenance history documents data, provides historical information for future maintenance planning, and supports maintenance trending of systems and equipment. The documentation of complete, detailed, and usable history is becoming increasingly important as historical data is analyzed for optimum maintenance actions that maximize equipment reliability and as support for plant life extension decisions. Trending is directed toward identifying improvements for the maintenance program and needed equipment modifications. The objective of good equipment history is to be able to readily retrieve equipment maintenance, performance, and reference information. The maintenance request (MR) work package may be useful as a maintenance history data collection tool. Maintenance history includes documentation of component identification and description, vendor reference information and correspondence, diagnostic monitoring data, corrective and preventive maintenance or modification information, and spare parts information. Maintenance standards should clearly define guidance addressing maintenance history for the systems and equipment to be included, what to collect, how to record data, and how the data is to be used. This history may be maintained centrally or locally by the individual group responsible for collecting the data. In either case, provide easy access to all groups needing this information.
Procedural controls for maintenance history clearly define the systems and equipment that require documentation and retention of historical data. At a minimum, include systems and components that could affect safe and reliable operation in the maintenance history program. Equipment requiring repetitive maintenance should also be considered for inclusion. Maintain this compilation of system and equipment information in an engineering database and allow easy cross-reference to information such as the equipment unique identification number and name, system, manufacturer, model, serial number, other appropriate nameplate data, lubrication data, applicable vendor manuals and drawings, spare parts reference numbers, setpoint data (control of data changes should be maintained), environmental qualification requirements, and common equipment cross-references. The master equipment list may be used to establish this baseline compilation.
Clearly define the type of data to be collected and recorded. Some examples of data to include or cross-reference in equipment history are as follows:
· corrective maintenance records with failure modes and causes included
· appropriate preventive and predictive maintenance records and design modification packages
· as-found condition during corrective and preventive maintenance
· vendor repair information (for example, correspondence on component repairs and modification bulletins)
· startup tests and other baseline data
· appropriate surveillance test data
· calibration data
· spare parts information
· applicable industry experience information
Data collected for maintenance history should be complete and comprehensive, with sufficient review to identify and correct deficient input. Data on systems and equipment that has been selected for history retention is sent to the person or group responsible for maintenance history entry. Maintenance requests are reviewed for history retention applicability, and data is entered in the maintenance history program. Any apparent errors, inconsistencies, or lack of detail are referred back to the maintenance manager or another appropriate manager for resolution.
Provide readily available maintenance history data for use by all departments, especially maintenance, training, and technical support departments. If maintenance history is computerized, train users to access and manipulate the history databases.
Maintenance planners, coordinators, managers, and craftsmen may use maintenance history on a routine basis for maintenance planning to provide data such as previous maintenance work and results, special tool needs, type and quantity of lubricants needed, manpower and time requirements, parts information, and procedure or instruction needs.
Maintenance history should be periodically and systematically reviewed and problems trended. This can be done manually or with automated analysis techniques. Persistent or recurring equipment and system problems should be reported to maintenance or technical support engineers for corrective action. This review should include recurring failures of a specific component and also failures of the same make/model component used in other applications. These reviews can also help identify areas where decreased maintenance effort is warranted (for example, reduced preventive maintenance frequency).
Uses of maintenance history data are as follows:
· reliability-centered maintenance analysis (provides essential data for identifying failure modes and failure causes and mechanisms)
· conduct of maintenance assessments -- provides an input to identify rework for the purpose of identifying maintenance program improvements
· preventive maintenance effectiveness -- provides some of the data useful for program assessment, identifying and justifying preventive maintenance scope and frequency adjustments
· program changes and evaluation of preventive maintenance necessity to reduce standby safety system unavailability
· outage planning -- provides some of the data useful for post-outage evaluation and as a basis for planning the next outage
· budget preparation -- provides an input for determining future maintenance needs based on experience and a justification for these expenditures
· provides some of the data needed to support extension of plant design life
· review of training effectiveness; knowledge of persistent system problems that may provide insight to training program revision