Planned Preventative Maintenance vs Reactive Maintenance

Planned preventative maintenance (PPM) means doing the servicing on a schedule, before anything fails. Reactive maintenance means repairing equipment once it has broken. Most plants run both, and the useful question is which one each machine deserves. This article compares the two, shows how to decide, and covers where extra people fit in.

What is reactive maintenance?

Reactive maintenance, also called breakdown maintenance, means you step in after the equipment has failed. EN 13306, the maintenance terminology standard, calls this corrective maintenance and includes repairs put off until a convenient time after the fault is found.

Its attraction is simplicity. There is nothing to plan and nothing is spent on equipment that is running fine. For a cheap item that stops nothing else, a spare on the shelf and a repair when it fails can be the sensible choice.

The cost shows up when the failure is on something that matters. The stop comes at a time you did not choose, the parts and people you need may not be to hand, and a failed part can damage the ones around it.

What is planned preventative maintenance?

PPM is a set of tasks done at fixed intervals, by calendar or by running hours: inspections, lubrication, adjustments and replacement of parts that wear. The intervals usually start from the manufacturer’s manual and are adjusted with your own failure history. You may also see it called planned preventive maintenance.

Done well, it turns a surprise into a booked job. You choose when the machine stops, order the parts in advance and arrange the people. It also leaves records of what was checked and when, which helps when an auditor or a client asks.

It has its own cost. You do work on equipment that might have run for longer, and a badly built schedule means effort spent on tasks that change nothing.

PPM and reactive maintenance side by side

• When you act. Reactive: after the failure. PPM: before it, to a schedule.
• Cost pattern. Reactive: little in normal weeks, then a spike when something goes. PPM: steadier and easier to budget.
• Stoppages. Reactive: at the time the machine chooses. PPM: when you choose.
• Safety. An unexpected failure can put people at risk. PPM reduces that by catching wear first.
• Records. PPM leaves a trail of inspections. Reactive leaves a history of breakdowns.
• People and parts. PPM lets you plan them ahead. Reactive means finding them at short notice.

How to decide which machine gets which

Rank your equipment by what happens when it fails. Four questions do most of the work:

1. Does the plant, or a whole line, stop if this fails?
2. Is there a spare or a standby unit?
3. Is there a risk to safety, quality or the environment?
4. How long does it take to get the part?

Critical equipment with no standby, a safety risk or a long wait for parts belongs on PPM. A cheap, non-critical item with a spare can be left to run to failure. Most plants end up with PPM on the important items and a controlled reactive approach on the rest.

A third option goes further than PPM for equipment that gives warning before it fails: measuring its condition and acting on the readings, which we cover in what is predictive maintenance.

Building a PPM schedule

1. Start from the manufacturer’s recommendations for each asset.
2. Add your own failure history. If a bearing fails every year, the manual’s interval is wrong for your plant.
3. Group the tasks by interval, so one visit covers several jobs.
4. Put the heavy tasks in the shutdown. What cannot be done while the plant runs goes in the planned stop.
5. Record what you find, not only that the task was done. Findings are what let you adjust the intervals.
6. Review it once or twice a year and drop the tasks that never find anything.

Where extra people fit

Planned work can be booked ahead, so it is the easiest kind to cover with outside technicians: a shutdown, an overhaul or a peak in the schedule. Breakdown work is harder to staff because it arrives without warning, so decide in advance who you would call.

What you ask for matters as much as when. Our article on what a maintenance technician does explains how to specify the trade rather than the title.

We provide technicians for industrial maintenance in Spain and Portugal. If you have planned maintenance coming up, tell us the dates and the scope as early as you can, and contact us.