If you’re new to the world of maintenance, the thought of staying on top of your duties and meeting compliance requirements can be daunting.
As a facilities manager, you need to have sound knowledge of your building and make sure you’re putting the right maintenance strategies in place.
Two strategies you might have heard of are predictive and preventive maintenance. And while they sound similar, they have very different approaches when it comes to equipment upkeep.
At SFG20, our whole purpose is to help you uphold the highest possible standard of building safety. With over 30 years of industry experience, we understand the importance of these strategies for organisations.
This article will help you understand the differences between predictive and preventive maintenance. By breaking down what each method means, looking at how and when you’d apply them, and comparing the pros and cons, you can go on to make an informed decision.
What is Preventive Maintenance?
Preventive Maintenance means actions taken to proactively address the root causes of potential failures or incidents and intervene before the risks become unacceptable. Better known as Planned Preventive Maintenance (PPM), it is a proactive approach designed to prolong the lifespan of assets, infrastructure resources and equipment.
This strategy helps to:
- Reduce unexpected breakdowns
- Prevent costly repairs
- Improve the longevity of equipment
PM involves carrying out regular inspections, services and maintenance on assets. This helps to keep assets in the best possible working condition, minimising the risk of unexpected failures that could result in increased downtime and costs.
Typical preventive maintenance approaches include:
- Time-based maintenance – this involves scheduling maintenance activities at regular intervals. This could be on a daily, weekly, monthly, or annual basis.
- Usage-based maintenance – maintenance is based on the asset’s utilisation. This could be after a certain number of operating or production cycles.
- Condition-based maintenance – asset conditions are monitored for signs of failure to optimise maintenance scheduling.
Here are a few examples of preventive maintenance:
Routine Inspections
Carrying out regular scheduled checks on equipment can help to identify potential failures before they become a bigger problem.
This could be for electrical or fire alarm systems or HVAC units, for example.
Cleaning
Equipment that is dusty or dirty could lead to blockages and faults, especially in mechanical systems.
This is why frequent cleaning of equipment plays an important role in preventive maintenance.
Lubrication
Certain types of machinery may require regular lubrication to increase mechanical longevity
Lubricating moving parts can help to reduce friction and prevent premature wear.
Filter Replacements
Equipment that uses filters will need them to be changed regularly to maintain a clean operation and efficiency.
What Is Predictive Maintenance?
Predictive maintenance (PdM) is a proactive strategy and is a sub-set of Preventive used to maintain and prolong the lifespan of:
- Assets
- Plant Equipment
- Infrastructure
Predictive maintenance is a proactive maintenance strategy that uses data from real time sensors and machine learning to predict when equipment is likely to fail.
By analysing historical and real-time performance data, organisations can schedule maintenance just before a problem occurs, which minimises unexpected downtime, reduces costs, and extends the lifespan of assets.
This strategy uses data-driven decision making to reduce the risk of unplanned breakdowns by predicting the likelihood of possible failures and acting on them early.
There are different types of techniques that can be used to monitor key performance parameters; their use will all depend on the equipment you’re gathering data from.
Here are some examples of common conditions that can be monitored:
Vibration Analysis
Primarily used on equipment that has rotating components that use bearings, Vibration analysis works by collecting vibration signals through specialised sensors.
The findings recognise the machinery’s patterns, which can then be compared to real-time data.
As the bearings wear, this helps to detect when the machine is out of sync, which can point to possible failures before they become a bigger issue.
Oil Analysis
Analysing a machine’s oil can help to:
- improve performance
- avoid malfunctions
- increase its lifespan.
An oil analysis process measures properties such as temperature and viscosity, and looks for foreign bodies, like metal shavings, which can indicate a failing asset.
While some elements of this can be carried out remotely with electronic sensors or specialist equipment, you may need to collect and send samples to be analysed by a qualified laboratory professional.
Most businesses will find they need to collaborate with qualified professionals, as it involves specialised equipment and/or a laboratory.
Acoustic Analysis
By monitoring sound frequencies on operating machinery, acoustic sensors can detect changes in sound patterns.
Rotating machinery will particularly benefit from this technique as it helps to identify friction and stress, which could point to deterioration.
Acoustic analysis can also be used for processes involving fluid flow in pipes and pressure vessels.
Infrared Monitoring
Monitoring the temperature of a machine can help to detect issues in machinery, electrical systems, and even building structures.
This is why infrared monitoring is such a widely used maintenance technique.
Sensors look for abnormal heat signatures, such as hotspots and fluctuations, to highlight possible malfunctions before they happen.
The Pros and Cons of Preventive Maintenance
The Pros of Preventive Maintenance
- Keeps your organisation compliant by regularly testing and servicing equipment.
- Improves safety levels for workers. Equipment that is properly maintained is less prone to malfunctions.
- Helps to extend asset lifespan due to routine checks.
- Improves reliability and minimises downtime.
- Increases energy efficiency. Electrical and mechanical assets that are poorly maintained or faulty can often consume significantly more energy than those operating as designed.
- Saves you money in the short term.
- Helps with budgeting because of the consistency of scheduled servicing.
The Cons of Preventive Maintenance
- Requires additional resources, such as more staff and greater time allocation for maintenance procedures.
- Increased risk of unnecessary maintenance on equipment that has parts or services before they are needed. This can waste time, materials and labour.
- Potential for higher costs in the long term.
- Not as data-driven, therefore less efficient.
The Pros and Cons of Predictive Maintenance
The Pros of Predictive Maintenance
- Saves you time and money by reducing unnecessary repairs and replacements.
- Helps to avoid unexpected breakdowns or unnecessary maintenance work.
- Ensures assets are running properly to create a safer working environment for people using your building.
- Helps to increase asset lifespan.
The Cons of Predictive Maintenance
- Investing in these types of sensor systems can be costly to start with.
- Organisations that don’t have experience with these systems may find it complicated.
- It can take some time to gather enough data to get predictions from the system.
- As with all technology, things can go wrong, which can affect accuracy.
Preventive vs Predictive Maintenance
While preventive and predictive maintenance are similar in that they both take a proactive approach, there are some key differences:
Preventive maintenance:
- Isn’t data-driven, which makes it less efficient.
- Is carried out at regular intervals, depending on time or usage statistics, as opposed to equipment condition
- Is carried out despite the condition of equipment
- Lower costs in the short term but can incur higher costs in the long term due to over-maintenance or parts being replaced earlier than needed.
Preventive maintenance would be better for assets that benefit more from having scheduled services. For example, exit and emergency lighting – this is something that must work during an emergency; failure isn’t always obvious, and it poses a risk if it doesn’t work when needed.
Predictive maintenance:
- Relies on real-time data and advanced analytics
- Is only performed when collected data indicates a potential failure
- Is usually carried out before a failure is likely to occur
- Has higher costs in the short term. This is due to investment in equipment, software, training, etc. But it is more cost-effective over a longer timeframe.
Predictive maintenance is best suited for assets that can be effectively monitored; otherwise, it could be a waste of resources if preventive schedules were applied.
Both can play an integral role in an organisation’s maintenance schedule.
Finding the Right Maintenance Strategy for You
You now know how and when predictive and preventive maintenance would be applied, and how exactly they differ.
However, it’s easy to feel overwhelmed when considering the many different types of maintenance strategies there are to choose from.
At SFG20, we want all FM professionals to have access to straightforward guidance to help them meet their responsibilities and building safety with complete confidence.
To compare other strategies and find out which is suitable for your organisation, take a look at these related articles below.
