The difference between routine and predictive maintenance

Routine and predictive maintenance are two techniques in preventive maintenance that aim to minimize the chance of equipment failures before they happen. A company may use separate or a combination of routine and predictive maintenance. So what is the difference between these two techniques?

Periodic maintenance (PM)

Routine maintenance is the activity of regularly checking, cleaning, and maintaining equipment to keep it operating in its optimum conditions and at the intended performance level. Regular routine maintenance reduces the possibility of equipment failures and prolongs the life of your equipment.

Production and maintenance work together to plan routine maintenance activities to minimize downtime, which in turn leads to improvements in communication, collaboration, teamwork, and engagement.
Ideally, routine maintenance tasks are scheduled at times with the least impact on productivity, such as at night or at the beginning or the end of the day. Maintenance can be scheduled based on equipment failure history. Root cause analysis is performed for equipment failures, providing solutions to prevent the same failure from recurring.

Tasks can be scheduled based on date or usage history, usually as recommended by device manufacturers. For example, many elevator manufacturers recommend performing maintenance after 150-200 hours of operation.
Regular maintenance can come with a cost, but the amount spent to minimize the likelihood of a failure will be almost less than the cost of machine failure. Even so, the PM approach is not without challenges. Devices that operate around the clock need to shut down to complete maintenance tasks, which means downtime is inevitable. As a result, implementing PM can be costly.

In short, there are some obvious benefits of routine maintenance (PM) as follows:

• Increase the life of the device
• Cost effective by eliminating and preventing equipment failures
• Improve and maintain productivity
• Reduce unexpected downtime
• Improve communication and teamwork
Predictive Maintenance (PdM)

Many businesses have carried out periodic maintenance. But not all businesses have dug deep by asking the question: Was the failure discovered before it could possibly happen?
This is where predictive maintenance comes in. The purpose is to use machine re

iability metrics such as MTBF (Average Time between two machine failures) and part failure history to determine the probability of critical parts failure (causing stop the machine). That way, you can predict when equipment failures will occur, and assign maintenance tasks to be performed before they happen.

With continuous technological advances, many companies are using techniques such as thermal imaging, vibration analysis and oil analysis to predict failures. Thermal imaging, for example, makes it possible to use infrared to photograph the device and to identify any hot spots, thereby accurately identifying potential problems. Most of these techniques can be performed while the machine is running.

By monitoring performance, maintenance personnel can foresee potential problems so that repairs and replacements are made before actual failures occur. Therefore, maintenance is only required when required and production time is not affected.

The aerospace industry is prized for its safety and minimal death rates due to equipment failures. What did they do to achieve these outstanding performance stats? For many years, the industry has led the way using predictive maintenance techniques and continues to push leading technology solutions to detect failures before they happen.

Dealing with the causes of equipment failures directly also means less time required for preventive maintenance tasks. In theory, predictive maintenance minimizes the risk of failures occurring as low as possible. However, predictive maintenance can also be complicated and requires a higher initial investment than preventive maintenance, but if done well, the revenue to cost ratio can be quite high.

In short, the benefits of preventive maintenance are:

• The machine condition can be checked even while the machine is running
• Real-time device information driving repair and maintenance operations
• Identify potential faults to correct before stopping the machine
• Use device reliability data and error history to predict errors
• Reduce overall maintenance costs as equipment is not under maintenance or over-maintenance
• Provides full visibility of how the device works

The main difference between the two approaches is that PM may need to stop the device and PdM can be executed while the device is still running.

The main difference between the two approaches is that PM may need to stop the device and PdM can be executed while the device is still running.

While there is no right or wrong approach to maintenance, leveraging the benefits of both PM and PdM strategies is often considered the most cost-effective way to maintain equipment performance and prevent failures. . The addition of PdM allows to minimize the likelihood of failure without spending too much money from performing too many PM tasks. Both strategies are important for any business that wants to use a lean approach and comprehensive productivity maintenance (TPM) program.

Source: KaizenKulture