US 8,571,911 B1 · Facility life management method

Abstract

An improved method of selecting and planning the performance of various maintenance activities on a facility such as a nuclear power plant includes determining the net present value of a number of future net savings that are expected to result from performance of the maintenance activity at a given time, and selecting and planning the maintenance activities in a fashion that maximizes net present value. The method includes, for each of a number of components and a number of time periods, determining a change in the probability that a component will fail within a time period, with the change resulting from an assumption that a maintenance activity is performed. The change in probability is multiplied with the losses associated with a failure in order to determine a gross savings from which costs are subtracted to determine net savings. The probabilities of failure may be determined from a probability failure model that has been derived from multiple sets of failure data that are characterized by Weibull distributions and are mathematically combined according to Bayes' Theorem. The maintenance activities may also be optimized according to a number of budget figures. An apparatus for performing the method is also disclosed.

Claims42

Dependent claims

A method of employing a computer in optimizing the timing of a number of maintenance activities that relate to a number of elements of a facility, the method comprising:

for each maintenance activity, employing the computer in:
determining a number of failure probabilities of an element based upon an assumption of performance of the maintenance activity at a given time,
employing at least some of the number of failure probabilities in determining a number of changes in probability of failure of the element based upon the assumption of performance of the maintenance activity at the given time, and
employing at least some of the number of changes in probability of failure in calculating a number of expected net savings based upon the assumption of performance of the maintenance activity at the given time;
employing the computer in performing said determining, employing, and calculating for each of a number of assumed given times of performance of the maintenance activity;
for each of at least some of the maintenance activities, employing the computer in determining the given time at which the corresponding expected net savings result in a substantially maximum net present value;
and
outputting from the computer a plan for the proactive performance of a number of the maintenance activities that is based at least in part upon said determining the given time.

5 more elements

A method of employing a computer in determining whether or not to plan the performance a maintenance activity that relates to an element of a facility, the method comprising:

employing the computer in:
determining a number of failure probabilities of the element based upon an assumption of performance of the maintenance activity at a given time,
employing at least some of the number of failure probabilities in determining a number of changes in probability of failure of the element based upon the assumption of performance of the maintenance activity at the given time, and
employing at least some of the number of changes in probability of failure in calculating a number of expected net savings based upon the assumption of performance of the maintenance activity at the given time;
employing the computer in performing said determining, employing, and calculating for each of a number of assumed given times of performance of the maintenance activity;
for each given time, employing the computer in calculating a net present value of the expected net savings;
employing the computer in identifying the maximum amount among the net present values;
employing the computer in determining whether the maximum amount is a positive amount or a negative amount;
and
outputting from the computer a plan for the proactive performance of the maintenance activity that is based at least in part upon said determining whether the maximum amount is a positive amount of a negative amount.

7 more elements

A method of employing a computer in maintaining a facility, the facility including a number of elements, the method comprising:

selecting a number of the elements according to a number of criteria;
identifying a number of failure mechanisms for the selected elements;
developing a number of the maintenance activities to correspond with the failure mechanisms;
for each maintenance activity, employing the computer in:
determining a number of failure probabilities of an element based upon an assumption of performance of the maintenance activity at a given time,
employing at least some of the number of failure probabilities in determining a number of changes in probability of failure of the element based upon the assumption of performance of the maintenance activity at the given time, and
employing at least some of the number of changes in probability of failure in calculating a number of expected net savings based upon the assumption of performance of the maintenance activity at the given time;
employing the computer in performing said determining, employing, and calculating for each of each of a number of assumed given times of performance of the maintenance activity;
for each of at least some of the maintenance activities, employing the computer in determining the given time in which the corresponding expected net savings result in a substantially maximum net present value;
and
outputting from the computer a plan for the proactive performance of a number of the maintenance activities that is based at least in part upon said determining the given time.

8 more elements

Dependencies are inferred from the claim text.

Facility life management method

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Facility life management method

Life of this patent

Abstract

Claims42