Preventive Maintenance or Corrective Maintenance?
Preventive Maintenance and Corrective Maintenance are two very different maintenance strategies. Therefore, you need to decide whether to perform maintenance before or after a failure has occurred.
Which strategy is then the best match for your Maintenance Team? It all depends on the type of equipment you need to maintain. Furthermore, it is important that you choose a maintenance system with flexibility to match your needs.
Basically, most maintenance systems are operating with several methods of scheduling trigger-based maintenance tasks, but it also needs to be combined with a maintenance strategy.
Preventive Maintenance: The Strategy of Preventing Failure
Preventive Maintenance is basically a type of maintenance that is done on a regular basis while the equipment is still functioning. The objective is to prevent failure, minimize the consequence of failure or assessing the risk of failure occurring.
When performing preventive equipment maintenance, you plan to replace an asset at a fixed interval regardless of its condition.
Preventive Maintenance include different methods for planning maintenance and may be performed based on triggers such as time, usage or condition.
Many companies combine the triggers. Take a car for example, it may need oil change, and this is scheduled for every year or 20.000 km. The system then automatically triggers the due date for the job no matter what frequency instance comes first – date or km.
Calendar Based Maintenance
Calendar Based Maintenance refers to replacing or renewing an item to restore its reliability at a fixed time regardless of its condition. The time interval may be fixed at every week, every month or every three months.
Calendar Based Maintenance is highly effective for age-related equipment or parts, where you know it tends to last for a certain amount of time. This method is used by most companies as it makes planned maintenance relatively easy. However, with this method you may risk maintaining your equipment too often or the other way around.
Counter Based Maintenance
Counter Based Maintenance is when you perform maintenance based on usage, which is typically running hours, e.g. every 1000 hours. You may also plan maintenance based on the number of events or operations such as every 200 cycles.
Counter Based Maintenance gives you a more accurate date for the maintenance task as it is based upon the actual usage of the equipment, which saves maintenance costs.
For many companies, the read out of the counter value is still a manual process, but with today’s IoT development, it is possible to automate these readings. Optimally, companies should collect the values automatically on an agreed time schedule such as every second hour or even live if possible.
Condition Based Maintenance
Condition Based Maintenance is a method where you monitor the real-time condition of an asset to determine what maintenance tasks needs to be performed.
This is typically based upon measurement or values coming from a monitoring/SCADA system. The idea is that this real-time monitoring will give Maintenance Teams enough lead time before a failure occurs or performance drops below an optimal level. You can also implement regular visual inspections or tests to check the condition of your equipment. The most common conditions to measure include vibrations, temperature, pressure, oil and noise.
The main goal of condition-based maintenance is to help you optimize your maintenance resources by performing maintenance work only when needed.
Condition Based Maintenance is highly effective for equipment where you have the possibility to measure the performance. However, this method requires an investment in special tools and monitoring systems, which may not make sense to all types of equipment economically. It is therefore the rarest method used.
Corrective Maintenance: The Fire Fighting Strategy
Corrective Maintenance (also known as breakdown maintenance) is maintenance tasks that corrects a problem with an asset and returns it to proper working order. The purpose of corrective maintenance is to restore broken equipment.
Corrective Maintenance tasks can be both planned and unplanned and may even be the result of a deliberate run-to-failure strategy. For certain type of equipment this strategy is still cost effective enough compared with Preventive Maintenance. You simply run the equipment till its end-of-life and then replace it.
Corrective Maintenance is often used when failure to the specific equipment is acceptable and not critical. Corrective Maintenance is also the result of unplanned failures which were not avoided through Preventive Maintenance.
Emergency Maintenance is maintenance required when an asset or piece of equipment suffers an unexpected breakdown or change in condition that results in an immediate threat to health and safety.
Emergencies always happen without warning, so emergency maintenance cannot be scheduled, but having properly prepared and executed preventive maintenance program will eliminate almost all emergency maintenance.
Emergency Maintenance is not a chosen strategy and Maintenance Teams do their best to avoid this. It often involves a high amount of unexpected working hours and is the most expensive type of maintenance.
A Maintenance System that supports both Preventive Maintenance and Corrective Maintenance
In SERTICA you can plan all your maintenance activities and your Maintenance Team can use simple apps to perform their daily tasks and reporting.
You keep all data, history and tasks centrally and eliminate most firefighting. You can set up preventive maintenance triggers on critical equipment and use the run-to-failure strategy on non-critical equipment.
Implementing SERTICA you get all the support you need to digitalize and optimize your internal maintenance processes.