What is planned maintenance?
Planned preventive maintenance—or PPM—is planned, documented and scheduled to be completed before a breakdown occurs. This is unlike unplanned maintenance. The process of planning the maintenance makes the tasks more efficient and eliminates the effect of maintenance on the operations of the facility.
Planned maintenance can be one of two types:
Planned and scheduled
The maintenance can be planned and scheduled. This is known as scheduled maintenance. A plan for car service every six months is this type of scheduled maintenance.
Planned and unscheduled
The maintenance can be planned and unscheduled. A plan to fix a light bulb with a replacement when it stops working, is this a type of planned maintenance.
Planned scheduled maintenance activities are planned with regard to the maintenance tasks and their timing. All of the triggers for scheduled maintenance are used as triggers for this type of maintenance. These are include time, usage, event and condition based triggers.
Being planned, the resource requirements are known and can be made available in advance. Being scheduled, a time for the maintenance is also known. When this is combined with the resource planning, the resources can be pre-arranged so that they are ready to go as soon as the job can begin.
The maintenance may be scheduled with both short and long lead times. Some scheduled maintenance may be planned years in advance, as would be the case for a yearly maintenance schedule, such as one to replace air-conditioner filters every year before summer. Other scheduled maintenances may have shorter lead times. These may be as a result of usage based schedules.
For a maintenance technician, this style of maintenance is more efficient than unplanned maintenance because the task is known in advance. As a result, the parts and supplies can be ready to go and other equipment that might make the job site unsafe can be safely shut-down. Consequently, a planned maintenance task can get done faster with the equipment returning to production faster, too.
Also known as run-to-failure maintenance.
Planned but unscheduled maintenance occurs in situations where the maintenance plan for an asset is to wait for breakdown before performing maintenance. A common example is waiting for a lightbulb to blow before replacing it.
With this style of maintenance the process for performing the maintenance is planned without knowing when it will occur. This means that the resources such as parts, supplies and personnel are ready and available to use so that the repair can be made within a reasonable time.
The trigger used for this maintenance type is a breakdown trigger.
This type of maintenance can be efficient for a technician when the maintenance has a low impact on production. It means that no extra maintenance resources are wasted on a part that can be replaced on an as-needs basis. For more information see the run-to-failure maintenance information page.