Plant maintenance method and apparatus

An apparatus for maintaining plant equipment comprising:

• an input unit configured to receive information on targets and ranges of plant equipment to be maintained, that constitute a plant, inspection information and operation-history information;
• an inspection-priority item selection unit configured to select a priority item, which relates to a failure event in a failure-event tree and is stored in a failure-event tree database, as items to be inspected;
• an inspection unit configured to inspect the selected items;
• a failure-event tree breakdown unit configured to perform tree-breakdown on failures to be expected from a failure-events to be inspected, in order to obtain a failure-event tree;
• a failure-unreliability function calculation unit configured to calculate unreliability of a resultant event in the failure-event tree with respect to a causal event in the failure-event tree preceding the resultant event;
• a failure-derived monetary loss calculation unit configured to multiply each unreliability and a cost of recovery from each event to be inspected and accumulate results of multiplication in accordance with the failure-event tree breakdown, thus obtaining a recovery cost;
• a preventive-maintenance expense calculation unit configured to calculate preventive maintenance expenses for preventing failure events;
• and
• a maintenance decision-making unit configured to decide maintenance timing and technique through comparison between the recovery cost and the preventive maintenance expenses.

An apparatus for maintaining plant equipment comprising:

• an input unit configured to receive information on targets and ranges of plant equipment to be maintained, that constitute a plant, inspection information and operation-history information;
• a monitoring-item selection unit configured to select a priority item, which relates to a failure event in a failure-event tree and is stored in a failure-event tree database, as items to be monitored;
• an on-line monitoring unit configured to monitor the selected items;
• a failure-event tree breakdown unit configured to perform tree-breakdown on failures to be expected from a failure-events to be inspected, in order to obtain a failure-event tree;
• a failure-unreliability function calculation unit configured to calculate unreliability of a resultant event in the failure-event tree with respect to a causal event in the failure-event tree preceding-the resultant event;
• a failure-derived monetary loss calculation unit configured to multiply each unreliability and a cost of recovery from each event to be inspected and accumulate results of multiplication in accordance with the failure-event tree breakdown, thus obtaining a recovery cost;
• a preventive-maintenance expense calculation unit configured to calculate preventive maintenance expenses for preventing failure events;
• and
• a maintenance decision-making unit configured to decide maintenance timing and technique through comparison between the recovery cost and the preventive maintenance expenses.

A method of maintaining plant equipment comprising the steps of:

• receiving information on targets and ranges of plant equipment to be maintained, that constitute a plant, inspection information and operation-history information;
• performing tree-breakdown on failures to be expected from events to be inspected, thereby obtaining a failure-event tree;
• calculating unreliability of every resultant event in the failure-event tree with respect to corresponding causal event in the failure event tree;
• multiplying each unreliability and a cost of recovery from each event to be inspected and accumulating results of multiplication in accordance with the failure-event tree breakdown thereby obtaining a recovery cost;
• calculating preventive maintenance expenses for preventing failure events;
• and
• deciding maintenance timing and technique through comparison between the recovery cost and the preventive maintenance expenses.

A method of maintaining plant equipment comprising the steps of:

• receiving information on plant equipment to be maintained, that constitute a plant, inspection information and operation-history information;
• selecting a priority item, which relates to a event in a failure-event tree and is stored in a failure-event tree database, as items to be inspected;
• inspecting the selected item;
• performing tree-breakdown on failures to be expected from events to be inspected, thereby obtaining a failure-event tree;
• calculating unreliability of every resultant event in the failure-event tree with respect to corresponding causal event in the failure event tree;
• multiplying each unreliability and a cost of recovery from each event to be inspected and accumulating results of multiplication in accordance with the failure-event tree breakdown, thereby obtaining a recovery cost;
• calculating preventive maintenance expenses for preventing failure events;
• and
• deciding maintenance timing and technique through comparison between the recovery cost and the preventive maintenance expenses.

A method of maintaining plant equipment comprising the steps of:

• receiving information on targets and ranges of plant equipment to be maintained, that constitute a plant, inspection information and operation-history information;
• selecting a priority item, which relates to a event in a failure-event tree and is stored in a failure-event tree database, as items to be monitored;
• monitoring the selected items;
• performing tree-breakdown on failures to be expected from events to be inspected;
• calculating unreliability of each item in the failure-event tree breakdown;
• multiplying each unreliability and a cost of recovery from each event to be inspected and accumulate results of multiplication in accordance with the failure-event tree breakdown, thus obtaining a recovery cost;
• calculating preventive maintenance expenses for preventing failure events;
• and
• deciding maintenance timing and technique through comparison between the recovery cost and the preventive maintenance expenses.

A method of maintaining plant equipment comprising the steps of:

• transmitting, over a network, data from inspection and monitoring units for equipment that constitute each of a plurality of plants, each plant having a plurality of units;
• processing the transmitted data through failure-event tree breakdown, failure-unreliability function calculation, failure-derived monetary loss calculation, failure-derived monetary loss calculation and preventive-maintenance expense calculation;
• and
• storing the processed data in a failure-event tree database and a failure-unreliability function database for learning, for accurate failure-unreliability function calculation in maintenance decision making;
• and
• transmitting results of maintenance decision making to the plants.