Predictive vs preventive maintenance
Table of Contents
The purpose of maintenance is to increase the reliability of your devices. Well-operating devices help your customer to reduce downtime and emergency maintenance breaks.
There are three basic types of maintenance strategies you can have: reactive maintenance, preventive maintenance and predictive maintenance.
Reactive maintenance, also known as breakdown or ‘run to failure’ maintenance, means that you go and fix your device when it is broken. The latter two strategies aim to be proactive in eliminating failures.
In the two proactive strategies the maintenance work is scheduled well before the actual work is performed, therefore they are referred to as ‘scheduled maintenance’. Both maintenance strategies have the same goal but differ significantly in the way they are organized.
This article explains the differences between these two approaches for doing proactive planned maintenance. This article also discusses how these two approaches affect your business.
What is preventive maintenance?
Just as with your car, the preventative maintenance will increase the functional life of your devices as well as improve their performance. This is naturally a great benefit for industrial customers who want to keep their processes running and maximize the profitability of the investment.
When should you use preventive maintenance?
Preventive maintenance has major challenges, however. The key issue is to balance between the cost of the maintenance and the achieved cost savings. You want to avoid over-maintenance.
Preventative maintenance runs well if your product is standard and it runs in standardized operating environment. This way you have learned from the past what is the correct maintenance frequency.
However, if either your devices or the operating conditions have variability, you will have challenges in defining the proper frequency of the maintenance activities. To do this, you will need high expertise in maintenance management, which is a cost.
Basically, preventive maintenance runs well in stable conditions and it’s easy to implement. You can start without any maintenance software. However, in more demanding environments it is not cost effective anymore as you will be doing unnecessary maintenance work.
Business impact of preventive maintenance strategy
Research on maintenance strategies shows that preventive maintenance generates cost savings in the range of 12 – 18 % compared to reactive maintenance. Because of this, industrial companies have a rule of thumb of allocating an annual maintenance budget of 10 – 20 % of the investment cost of your device. This budget includes paid services as well as the costs for their own maintenance activities.
A preventative maintenance program is something that the industrial companies are already familiar with. As a device manufacturer, you should be able to sell easily maintenance services that fall into the range of their already allocated maintenance budget, at least 5 – 10 % of your device price per year.
What is Predictive Maintenance?
With a quick look, one might think that preventive and predictive maintenance are quite similar maintenance strategies. Both aim to eliminate failures.
They are not. There is a fundamental difference. In predictive maintenance strategy, the maintenance tasks are not scheduled according to calendar time or running hours. Instead, the activities are scheduled based on measured performance of the devices. That makes it very cost effective by reducing unnecessary maintenance.
As an example, your car’s computer measures the condition of engine oil and the tire pressure. When the computer notices that the measurement values start trending towards a limit, the computer notifies the driver that “I need service in the next 60 days”.
When should you use predictive maintenance?
Condition based maintenance is especially powerful in situations, where there are differences in the operating conditions. It can be different weather, different process or different organizational culture of the customer.
Predictive maintenance allows you to detect whenever your devices start to perform outside normal parameters. This allows you to trigger maintenance to eliminate the upcoming failure. When you make your maintenance predictive, you become a lot more flexible and dynamic compared to preventative maintenance. Moreover, it allows you to learn why your devices behave in the way they do.
Since a predictive maintenance program is based on actual device condition, you must collect the data and you need a maintenance software.
Business impact of predictive maintenance strategy
Predictive maintenance generates 25 – 30 % cost savings compared to reactive maintenance. Even though this is already twice the savings compared to preventive maintenance, the biggest business impact is yet to come.
Research indicates a 70 – 75 % reduction in breakdowns, a 35 – 45 % reduction in downtime and a 20 – 25 % increase in productivity. These business benefits are not anymore related only to maintenance costs, these are related to the overall business. From your service business point of view, this gives you room to price your maintenance service a lot higher.
Condition based maintenance requires real time data on the operation. Without any extra effort, you can share this knowledge to your customer as well. This increases customer trust significantly and allows your customer to adjust his operations as well.
In brief, making your maintenance predictive will reduce cost, increase price and improve customer satisfaction. This makes it a good place to start your digital transformation.
Differences Between Predictive & Preventive Maintenance
Both ‘scheduled maintenance’ approaches are designed to be proactive in eliminating failures and therefore better than reactive, breakdown or ‘run to failure’ maintenance. In both programs the maintenance work is scheduled well before the actual work is performed.
Regardless of their similarities, the approaches are fundamentally different.
First difference is what triggers the work. In preventive maintenance, work is scheduled based on calendar time. In predictive maintenance you have real time information of your devices and you plan your work according that. This lowers your maintenance costs, allows a higher service price and increases customer trust.
Even though predictive maintenance having such benefits, why do 86 % companies have either reactive or preventive maintenance?
Predictive maintenance requires a lot more technology. You need data collection and maintenance software. Setting up such a program is thought to be more expensive than setting up preventive maintenance. Therefore, companies choose the easy route.
However, the digital transformation has been a game changer in breaking the walls between different maintenance strategies. In the age of cloud computing, web applications and global mobile networks, the cost of setting up predictive maintenance has lowered to a fraction of what it was a decade ago. Modern digital tools also simplify maintenance management, no matter on which stage you are.
So now that you know the differences, should you take the preventive or predictive maintenance approach? Or is there something in the middle?