IS MACHINE MONITORING WORTHWHILE?
Schaeffler Australia
Choosing the right maintenance strategy depends on balancing cost, system criticality, and the value of early fault detection through condition monitoring.
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here are many ways of monitoring machines or even entire systems. However, monitoring for the early detection of damage and defects does not necessarily make good economic sense for every machine or system.
MAINTENANCE STRATEGIES
PROCESS TECHNOLOGY APR/MAY 2026
Run-to-failure maintenance
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Failure-based or reactive maintenance is also known as run-to-failure maintenance and is regarded as a passive strategy. With this form of maintenance, a system component is only replaced or repaired once it has actually failed. No information about the condition of the machine is collected or evaluated while the system is in operation. The problem with this approach is that the extent of the damage and the required restoration time cannot be predicted. The advantages of this approach are that no costs are incurred during smooth operation and the full wear reserve of the machine is utilised. Failure-based maintenance is suitable for machines or components that are not critical to production, are easy to replace, and do not lead to expensive consequential damage. The actual service life of machines and machine elements is often shorter than the basic rating life. Imbalance and misalignment (60%), bearing damage (20%), and other contributing factors such as structural problems, mounting issues and resonance (20%) are the most common causes that
can lead to unexpected system failures and production downtime.
Preventive maintenance In the case of preventive maintenance, it is assumed that a machine or system requires particular maintenance expenditure at defined time intervals. The definition of the time intervals is based on the average operating life of the system and on empirical values. Since the time intervals in this maintenance strategy are fixed, they can be integrated in a targeted manner into existing production operations or downtime planning. However, they do not necessarily correlate with the actual condition of the system. It is therefore possible that maintenance measures will be carried out prematurely, thus making an unnecessary claim on resources. Preventive maintenance is usually prescribed by the warranty provisions, as defined in the maintenance plan. When the warranty expires, a suitable monitoring strategy can be considered. In many cases, the switch is made to condition-based or predictive maintenance.
Condition-based maintenance With condition-based maintenance, the machines and systems are not serviced on the basis of failures or time, but according to the established condition of the components. With this strategy, condition monitoring is used to carry out maintenance PROCESSONLINE.COM.AU