Time-Based Maintenance vs. Condition-Based Maintenance

When it comes to maintenance, companies often face the decision between time-based maintenance and Condition-Based Maintenance (CBM)—two approaches aimed at improving reliability and reducing downtime, but which one should they choose?

Time-based maintenance (TBM) relies on scheduled interventions to prevent failures before they happen, typically based on fixed intervals of time or usage. In contrast, CBM uses data and condition monitoring to address issues only when necessary, allowing for more precise interventions.

The most effective maintenance strategy often involves using both time-based maintenance and CBM together to create an optimal maintenance program. This integrated approach combines the structured, time-based techniques with the data-driven assessments of CBM, enabling precise, condition-based interventions while maintaining proactive maintenance schedules. This balance enhances equipment reliability and reduces unplanned downtime.

In this article, we’ll explore both strategies to help you determine which one—or combination—is best suited to your company’s specific needs and operational goals.

Time-Based Maintenance: Definition, How It Works, and Benefits

TBM involves performing regular tasks on equipment at predetermined intervals, such as changing oil every six months or after a certain number of operating hours. These tasks are based on time or usage factors and are typically scheduled according to manufacturer guidelines or historical data. The key advantage of time-based maintenance is its simplicity and cost-effectiveness, as it can be easily implemented without requiring specialized technical resources.

However, time-based maintenance is not without its drawbacks. One major limitation is that the scheduled tasks are often intrusive, requiring equipment shutdowns even when no issues are present. This can lead to unnecessary planned downtime and over-maintenance. Additionally, because time-based maintenance doesn’t consider the actual condition of the equipment, it may result in interventions that could have been avoided with a more targeted approach.

Condition-Based Maintenance: Definition, How It Works, and Benefits 

Condition-Based Maintenance takes a more advanced approach by using data and analytics to predict failures before they happen. Unlike time-based maintenance, which operates on fixed schedules, CBM relies on condition-monitoring tools like vibration analysis, thermography, or IoT sensors to continuously monitor equipment status. These tools provide insights, which are then presented in a health dashboard.

The key advantage of condition-based maintenance is its precision. By monitoring equipment conditions continuously, it allows maintenance to be performed only when necessary, reducing the risk of over-maintenance. Additionally, it minimizes downtime and optimizes resources. However, implementing predictive maintenance requires a higher initial investment due to the advanced technologies and skilled personnel needed for its deployment.

Comparison Between Time-Based Maintenance and Condition-Based Maintenance 

The main difference between time-based maintenance and condition-based maintenance lies in their approach: TBM is based on fixed time or usage intervals, while CBM relies on data analytics and condition monitoring. Time-based maintenance is generally less costly but can lead to unnecessary expenses, while CBM requires a higher initial investment but offers long-term savings by detecting potential failures earlier. Time-based maintenance is easier to manage, especially for predictable wear, whereas CBM demands technical expertise.

How to Decide Between Time-Based and Condition-Based Maintenance

When choosing between time-based maintenance and condition-based maintenance, several factors should be considered: 

1. Asset Criticality: 
   Use condition-based maintenance for high-value or critical assets that require high reliability. Time-based maintenance works best for low-risk, non-critical equipment. 
2. Industry Requirements: 
   Certain industries, such as aviation, require strict time-based maintenance schedules due to regulatory standards. Other industries, such as manufacturing, may benefit more from condition-based maintenance strategies. 
3. Technology Readiness: 
   Consider your organization’s ability to implement and manage condition-based tools. If your team lacks the expertise or resources for such an investment, time-based maintenance may be a better starting point. 

Frequently Asked Questions (FAQ)

Here are some common questions related to time-based maintenance and condition-based maintenance: 

• Is time-based maintenance better than condition-based maintenance? 
  It depends on the asset type and industry needs. Time-based maintenance is simple and cost-effective, but predictive maintenance offers greater precision and long-term savings for critical assets. 
• Can condition-based maintenance replace time-based maintenance? 
  Condition-Based maintenance can complement or even replace time-based maintenance in certain scenarios, especially for high-value or critical assets where minimizing downtime is crucial. 
• Can I use both CBM and Time-Based Maintenance? 
  Yes, many organizations use a combination of both approaches. Time-based maintenance can cover routine tasks, while condition-based maintenance targets more complex or high-risk assets. 

Conclusion

The choice between time-based maintenance and condition-based maintenance (CBM) depends on several factors, such as asset criticality, budget, and industry requirements. While time-based maintenance is cost-effective and easy to implement, it can sometimes lead to unnecessary interventions. On the other hand, condition-based maintenance, though requiring a higher initial investment, offers a more precise and efficient approach—especially for critical assets. 

In practice, many businesses find that the best strategy is a hybrid approach, combining both TBM and CBM in parallel to ensure an optimal maintenance program. This combination allows organizations to balance cost, efficiency, and asset reliability by proactively addressing issues through time-based maintenance while monitoring asset conditions through CBM. By considering these factors, businesses can select the strategy or combination that best meets their long-term goals and operational needs. 

Raphael Tremblay,
Spartakus Technologies
[email protected]