Preventive maintenance is the maintenance work that is performed before trouble occurs. When is preventive maintenance performed and what is the effect? Introducing the points for preventive maintenance and a new form of maintenance that further evolves preventive maintenance. Maintenance work is sometimes called maintenance work, but for convenience, it is unified as maintenance work in this article.
What is preventive maintenance?
Let’s see why preventive maintenance is important in maintenance work and what kind of method is taken.
Maintenance work to prevent it
Preventive maintenance is performed for the purpose of maintaining operation by performing maintenance work on equipment and software before troubles and defects become apparent. The purpose is exactly “prevention”, and by finding potential defects and taking corrective actions, we prevent the occurrence of troubles. It can be said that this maintenance method focuses more on maintaining operations than maintenance work (post-maintenance) performed after trouble occurs. Generally, it is a term used for maintenance work of machines, equipment, and systems in general, but in recent years, it is often used in IT-related fields such as networks and software.
Differences and meanings between preventive maintenance and post-maintenance
What is the difference between the preventive maintenance performed before the trouble occurs and the post-maintenance performed after the trouble occurs?
Post-maintenance is maintenance work centered on repairs that are performed when the functions of running equipment or software stop or their capabilities deteriorate. We will investigate the cause of the problem and take measures to restore the function. In other words, post-maintenance is maintenance work performed to restore functionality.
On the other hand, preventive maintenance is performed before trouble or problems occur, as explained above. Regular inspections are carried out according to the maintenance plan, and regular maintenance such as regular replacement of consumable parts, grease up, software update, and backup is the main focus. The purpose of this is to prevent problems before they happen. In other words, preventive maintenance is maintenance work performed to maintain operation.
In this way, the main purposes and aims are divided into post-maintenance for functional recovery and preventive maintenance for maintenance of operation. Therefore, it is not enough to do only one of these two types of maintenance work, but it is said that the possibility that a problem will occur due to preventive maintenance will be reduced as much as possible, and the problem that has occurred will be dealt with by post-maintenance. So it’s important to be able to combine both.
In this way, both preventive maintenance and post-maintenance are indispensable, but it is said that preventive maintenance is particularly important. Basically, when it is necessary to perform post-maintenance, the operation of the target system has stopped in most cases. For this reason, it is better to prevent problems from occurring by preventive maintenance as much as possible so that post-maintenance is not required.
Risks of post-repair and benefits of preventive maintenance
Now let’s look more specifically at why preventive maintenance is considered important. Without preventive maintenance, you will continue to carry the following risks:
- Outage time occurs for repairs and repairs after a failure occurs
The outage directly leads to a decline in profits. Preventive maintenance prevents service outages due to wear of consumables and enables stable operation.
- Expansion of the range of correction required due to the effects of failures
It is possible for both machines and software to have an impact on other parts due to a defect in one place. Preventing defects by preventive maintenance also prevents the scope of such defects from expanding.
- Failure at a level that cannot be fixed or repaired
Without preventive maintenance, in the worst case, a level of failure that cannot be repaired can occur. In the event of such a failure, we must consider including the purchase of a new facility or system. In that case, not only the cost of a new purchase, but also the fact that the expected profit cannot be obtained from the time of internal approval, budgeting, ordering to delivery, and full-scale operation is a big loss. Preventive maintenance can prevent these levels of failure and predict when they will occur even if they cannot be prevented. By setting the renewal time in advance, you can avoid large losses.
- Shorter life and increased costs for parts and applications
If you continue to use parts and applications without maintenance, their lifespan will be shortened and replacement and renewal costs will increase. If regular maintenance is performed by preventive maintenance, not only will the average annual parts cost be reduced due to the longer life, but also the time taken for ordering and replacement work will be reduced, and costs will be further reduced.
- Out-of-budget maintenance work costs incurred
For repairs and corrections after a defect or failure occurs, the budget required for post-maintenance is not predicted, and costs outside the budget may be incurred. In preventive maintenance, maintenance work is performed regularly according to the maintenance plan, which makes it easier to make a budget plan for maintenance and reduces the occurrence of out-of-budget maintenance costs due to sudden failures.
Considering the role of preventive maintenance, the merits of preventive maintenance can be summarized as follows.
- Increased productivity by reducing downtime
- Narrowing down and standardizing correction points
- Avoiding large-scale failures
- Cost reduction
- Clarification of operation plan
Points of preventive maintenance
In order to maximize the benefits of preventive maintenance, some points need to be addressed with particular attention.
- Thorough time-based maintenance
In order to perform preventive maintenance, it is necessary to create an implementation program such as which item to perform maintenance work in what cycle. This kind of preventive maintenance plan based on time is called time-based maintenance. It is common to prepare a maintenance implementation calendar, make a plan, and fill in the implementation details.
- Clarified state maintenance standards
A preventive maintenance plan based on the condition, such as when parts should be replaced or maintained, is called condition-based maintenance, and the standard for that is the condition maintenance standard. Keep a record of how much deterioration it should be before replacing it, and then set a guideline for replacement.
Preventive maintenance can be carried out more efficiently by creating a maintenance plan by holding down these points. However, this requires a lot of experience from the maintenance planner to understand when the trouble occurs. It is also necessary to have the ability to accumulate maintenance work records and determine the timing of failure occurrence from them.
Beyond Preventive Maintenance-Predictive Maintenance
In order to carry out more efficient preventive maintenance, information for predicting the timing of trouble occurrence is required. Preventive maintenance based on this information collection and analysis, so to speak, “predictive maintenance” is attracting attention. This is an evolution of the maintenance plan, which was supported by the experience and intuition of the maintenance planner, into a more data-based one.
IoT and big data analysis make this possible. Information is collected by IoT, stored as big data, and data is analyzed. This is a method to find out the signs and periods that lead to the occurrence of troubles from the history so far, predict the time of occurrence, and make a maintenance plan.
Such a method is attracting attention as a new form of maintenance, “predictive maintenance”. In predictive maintenance, it is possible to specify the maintenance work timing in real-time. By instructing maintenance work and reviewing the production plan at the moment when a sign that trouble is predicted appears, we will maintain the state where the operation can be maintained.
The discovery of these signs and the prediction of defects are supported by big data analysis. In addition, edge computing contributes to rapid processing. By analyzing the data on the site side, the information sent from the equipment can be linked to predictive maintenance in real-time.
The importance of preventive maintenance and predictive maintenance grows even larger
I explained the meaning and importance of preventive maintenance, and what kind of predictive maintenance can be said to be a further evolution of preventive maintenance. Preventive maintenance is one of the maintenance methods whose necessity has been advocated for a long time, but in recent years it has become more important and has evolved into predictive maintenance. The reason is that we humans can now hear the “voice” of information sent from equipment and facilities. How to make more effective use of these “voices” and predict and prevent troubles will become important in future maintenance work.