If you’re new to the world of maintenance, it can be hard to know where to begin.
There are numerous maintenance strategies to choose from, each with a different approach that offers benefits suited to specific assets and equipment.
As the industry standard for building maintenance, SFG20 has been providing guidance on maintenance strategies for over 30 years. So, if you’re feeling overwhelmed and in need of practical maintenance advice, you’ve come to the right place.
This article will explore predictive and reactive maintenance, two very different approaches to asset maintenance. You will learn how and when you’d apply each strategy and then be able to compare the pros and cons of each one.
What is Predictive Maintenance?
Predictive maintenance is a proactive strategy used to maintain and prolong the lifespan of:
- Assets
- Resources
- Equipment
- Infrastructure
Real-time, condition-based monitoring (such as vibration, pressure or temperature) helps identify potential issues before they occur.
This process is often combined with historical data which can come from either:
- Knowledge already generated from work orders and repair records
- Collection sources outside of the company
This accumulated data helps to identify the optimal time for carrying out a series of set procedures.
By predicting failures and acting on them early, this strategy helps to reduce unplanned breakdowns and potential major malfunctions. This can save on the maintenance costs that can come with this too.
Common techniques used in predictive maintenance include:
Vibration Analysis
By collecting vibration signals through specialised sensors, a machine’s patterns can be compared to real-time data to detect when it’s out of sync. This can point to possible failures before they escalate.
Vibration analysis is mainly used on equipment with rotating parts that use bearings.
Oil Analysis
All machinery that requires oil to function must have an oil analysis process.
It can help to:
- Improve performance
- Avoid malfunctions
- Increase its lifespan
Oil analysis measures properties such as temperature or viscosity and looks for foreign bodies such as metal shavings which could be an indicator of a failing asset.
Elements of this can be carried out remotely with electronic sensors or specialist equipment, however you may need to collect and send off samples to a qualified laboratory professional for a full analysis.
Acoustic Analysis
By monitoring sound frequencies on operating machinery,acoustic sensors can detect changes in sound patterns.
Rotating machinery particularly benefits from this technique as it helps to identify factors such as friction and stress which can suggest deterioration.
Acoustic analysis can also be used for processes involving fluid flow in pipes and pressure vessels.
Infrared and Thermal Monitoring
Temperature monitoring is a widely used maintenance technique that uses sensors to look for abnormal heat signatures.
If hotspots and fluctuations are found, this can highlight potential failures before they happen.
Monitoring the temperature of a machine can help to detect issues in machinery, electrical systems and even building structures.
What is Reactive Maintenance?
With reactive maintenance, there are no pre-scheduled plans with this strategy, rather action is only taken after a failure has been detected or identified as likely to happen.
The requirement for reactive maintenance can stem from the adoption of a Run-to-failure strategy, where an asset is left to operate until it breaks and is then either replaced or repaired.
This is applied to assets where the cost of repair is the same or less than putting preventative measures in place or where an asset is non-essential.
Even when a proactive approach is being used, assets can still fail unexpectedly. So, reactive maintenance is always a possibility for any organisation.
There are three common approaches to deal with reactive maintenance:
Emergency Maintenance
Emergency maintenance is when an asset breaks down and its repair is ‘time bound’, because it poses a threat to safety, property or is essential for the operation of a business.
This usually involves a quick repair or replacement to make the asset or issue safe. Often, further maintenance might need to be carried out to complete the task.
Routine Breakdown Maintenance
Breakdown maintenance is applied to equipment that stops working or malfunctions.
It is usually not ‘time bound’, i.e. it can wait to be dealt with and is based on a trigger event occurring or being reported. Resolution of the issue may be either planned or unplanned.
Corrective Maintenance
Corrective maintenance is normally a follow-up action following some form of inspection which identifies that an asset needs fixing or replacing.
This could be when an asset is worn and still functioning (but not optimally) or if it has broken down completely.
Corrective maintenance issues are often found during routine inspections.
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.
The Pros and Cons of Reactive Maintenance
The Pros of Reactive Maintenance
- Provides short-term cost savings.
- There’s no need to plan ahead.
- It can be the best option for certain assets such as low-value, non-critical or single-use assets (e.g. light bulbs, printer cartridges, etc.).
- Ideal for environments where maintenance requirements are hard to predict or enforce.
The Cons of Reactive Maintenance
- There’s a risk of legal repercussions. Maintenance engineers and contractors are not legally responsible for the work they do; they are only bound by the rules of the contract they sign with a Facilities Manager or Property Owner. With this in mind, it's essential to be fully aware of your compliance obligations.
- It can create unexpected downtime which can result in costs that typically far exceed the cost of asset replacement.
- As emergency repairs are more likely to incur higher costs compared to maintaining an asset, it can cost more in the long run.
- Delayed maintenance can pose safety risks, particularly in critical systems.
- Running an asset to failure can drastically shorten its lifespan.
Predictive vs Reactive Maintenance
As you’ve now learnt, predictive and reactive maintenance are contrasting maintenance strategies. In summary, predictive maintenance and reactive maintenance differ in that:
- Predictive maintenance aims to prevent failure and make replacements before they happen.
- Reactive maintenance waits for an asset to fail before repairing or replacing.
Predictive maintenance offers more reliability, reducing the risk of unexpected failures. This makes it ideal for critical assets where the costs of failure are high.
Reactive maintenance is a more cost-effective option in the short term but is better suited for non-critical assets with lower repair costs.
At SFG20, we advocate for implementing a mix of reactive and proactive, preventive strategies. This will help to create a good balance in your maintenance strategy, optimising both costs and operational reliability.
Finding the Right Maintenance Strategy for You
While it can be daunting to decide which maintenance strategies to use, it’s important to remember that there’s no one-size-fits-all approach.
You need to think about what will work best to keep your facility running as smoothly as possible.
At SFG20, we understand the challenges of developing and maintaining a practical maintenance plan, which is why we want to offer you as much of our guidance as possible.
To compare your options and help you find the right maintenance strategy for your organisation, take a look at these other articles below.
