Types of planned maintenance
- Preventive (time- or usage-based): tasks done at fixed intervals, such as every month or every 500 hours, regardless of condition.
- Condition-based: tasks triggered by what monitoring shows, such as vibration, temperature or an operator's inspection finding.
- Planned corrective: repairs for faults found during inspection or autonomous maintenance, scheduled before they cause a stop.
- Predictive: condition-based maintenance using trend analysis to forecast when intervention is needed.
Reactive maintenance, fixing after failure, is what planned maintenance aims to shrink to a minimum.
Why planned beats reactive
Planned work is done at a convenient time with the right parts and people, takes less time, and causes less collateral damage than a breakdown. A high share of reactive work is a sign of a weak maintenance system and shows up as availability loss in OEE.
Running planned maintenance
- Build the asset register with criticality, so the plan focuses on what matters.
- Define the tasks and intervals from manufacturer guidance, failure history and operator findings.
- Schedule and assign the work, with parts and permits arranged.
- Record what was done and found, so intervals and tasks can be adjusted.
- Measure planned versus reactive hours, schedule compliance and the breakdowns that still occur.
Planned maintenance and daily management
Overdue planned maintenance and the breakdowns that follow belong on the tier boards that production and maintenance share. When operators' autonomous maintenance checks find abnormalities, those become planned corrective work rather than the next breakdown.
Common mistakes
- Intervals copied from a manual and never revised against actual failures.
- Planned work repeatedly deferred because the line cannot be released, until it becomes a breakdown.
- No record of findings, so the plan never learns.