Component Failure Trending

DOE-STD-1052-93

9.1.1.5

The "as-found" scoring should be performed each time the PM

is performed, during power operations as well as outages.

9.1.1.6

Reports containing PM task scoring and proposed frequency

changes should be periodically provided to management.

To implement this method, it should be emphasized to

craftspersons that a good, detailed description of the "as-found"

condition of the component and the work performed should be

recorded on all PM maintenance job requests. This allows

engineering personnel to evaluate and trend the data to optimize

task intervals and determine effectiveness of the tasks.

9.1.2 Component Failure Trending

A PM program is designed to maintain the inherent reliability of equipment.

This reliability may be determined by analyzing the failure or performance

history of the component. Therefore, failures should be graphically trended

to produce a record of component performance and provide indicators to

facilitate changes in the component's design or existing PM tasks. The

trending program should-include selected critical components so that the most

effective adjustments to the PM program may be made.

Much of the data needed to establish a trending program is collected during

the initial enhancement effort. Some of the data includes failure time/date,

failure mode/cause, and statistically derived data such as failure rate. These

parameters may be determined from plant-specific data or from industry

sources.

Adverse trends in failure data is cause to initiate an evaluation or investigation

to determine and correct the causes of the problems. The following method

may be used to determine if the results of component failure trend analysis

warrant changes to the PM program:

If a PM task exists but the trend analysis shows an increase in failures,

a review of the component analysis may be necessary to determine if an

additional failure mode should be considered or if the adverse trend is-

caused by programmatic deficiencies. Additionally, consideration

should be given to decreasing the existing PM task interval.

D - 47