Changing your oil and rotating your tires every 3,000 miles or getting your teeth cleaned every six months are classic examples of time-based maintenance.
Time-based, or periodic, maintenance is a common type of preventive maintenance performed periodically. Companies perform time-based maintenance regardless of equipment condition. For example, an OEM may recommend lubricating a piece of equipment every 14 days to reduce wear and improve reliability. Plants schedule this as a recurring activity and plan accordingly. This practice helps improve the performance of the equipment and reduce risk of failure.
Advantages of time-based maintenance:
Including time-based maintenance in your long-term plant maintenance strategy can be beneficial. Some of the advantages of this strategy include:
- Simple and recurring time-based maintenance activities require minimal training for technicians.
- This type of maintenance increases asset reliability and saves on corrective maintenance costs for companies.
- Unlike condition-based maintenance, time-based maintenance doesn’t require additional sensors to determine the health of equipment, making it easy to implement.
- Time-based maintenance activities are performed as per a predetermined schedule. This helps maintenance managers allocate resources efficiently.
- For equipment that runs continuously, time-based maintenance is the right strategy as wear and tear of such equipment is more predictable.
Limitations to time-based maintenance:
The most obvious issue with time-based maintenance is that it doesn’t consider equipment condition. It’s based solely on the age and runtime of equipment. However, these two alone are not the root causes for equipment failures. There are several other factors to take into account such as environmental conditions, temperature, pressure, shocks and more. These failures are unpredictable and don’t occur at regular time intervals.
Time-based maintenance schedules should try to find the sweet spot between under-maintenance and over-maintenance. If the window between maintenance schedules is larger than it should be, assets will be at high risk of failures as they don’t receive due attention and care. Too frequent maintenance increases the risk of human errors, where technicians perform incorrect reassembly or apply inappropriate lubrication. Performing unnecessary maintenance leads to inefficiencies by wasting manpower and parts.
Since time-based maintenance doesn’t consider internal and external factors influencing equipment health, this strategy is well suited for assets that run continuously. It’s less appropriate for equipment that’s used occasionally.
Best Practices to Consider
Managers should identify the right candidates for time-based maintenance. This is a great approach for inspecting fire extinguishers and testing smoke alarms, which are very important to maintain occupational safety. Cleaning HVAC units and furnaces, likewise are seasonal activities that require proper attention at specific intervals.
Time-based maintenance plays a significant role in controlling wear and tear in critical equipment. Planning time-based maintenance schedules effectively still requires key data points such as historical asset maintenance data, OEM recommendations and mean time between failures (MTBF).
Using a comprehensive enterprise asset management (EAM) solution helps break data silos. This offers high quality asset data for maintenance managers and enables them to create an optimal time-based maintenance schedule.
