Scientists at the Pacific Northwest National Laboratory (PNNL) have examined the necessity for understanding and controlling the aging process of both safety-specific plant components and the infrastructure that supports these processes. In this paper we examine the preliminary development of aging precursor metrics and their correlation with degradation rate and projected machine failure. Degradation-specific correlations are currently being developed at PNNL that will allow accurate physics-based diagnostic and prognostic determinations to be derived from a new view of condition-based maintenance. This view, founded in root cause analysis, is focused on quantifying the primary stressor(s) responsible for degradation in the component of interest. The derivative relationship between the performance, degradation and the underlying stressor set is used to gain a first principles approach to prognostic determinations. The assumptions used for the design basis of process equipment have always been as much art as science. This allows two major improvements in the operations and maintenance (O&M) of process machinery: 1) the actual versus intended machine environment can be understood and brought into much better alignment, and 2) the end goal can define operations and maintenance strategies in terms of life cycle and economic management of plant assets. A holistic infrastructure approach, as applied through a CBM framework, will allow intelligent, automated diagnostic and prognostic programs to provide O&M practitioners with an understanding of the condition of their machinery today and an assurance of its operational state tomorrow.
Revised: November 10, 2005 |
Published: March 1, 2004
Citation
Jarrell D.B., D.R. Sisk, and L.J. Bond. 2004.PROGNOSTICS AND CONDITION-BASED MAINTENANCE: A NEW APPROACH TO PRECURSIVE METRICS.Nuclear Technology 145, no. 3:275-286.PNNL-SA-37142.