Run-to-failure (RTF) maintenance

What is run-to-failure maintenance?

Run-to-failure (RTF) maintenance, also known as corrective maintenance (opens in new tab) or breakdown maintenance (opens in new tab), is a maintenance strategy where equipment and machinery are deliberately allowed to operate until they fail. During this time no preventive maintenance is performed on the equipment, and repairs or replacements are only made after a breakdown occurs.

Example of run-to-failure maintenance

Here's a practical example of run-to-failure maintenance in a manufacturing environment:

Let's say you run a factory that produces cardboard boxes. One of the pieces of equipment in your factory is a stapling machine, which staples the corners of boxes to secure them during the folding process. This stapler is a robust piece of equipment, but it's also inexpensive and easy to replace and not critical to the operation of the rest of the factory.

Instead of inspecting this stapling machine on a regular basis or trying to predict when it might fail, you adopt a run-to-failure approach. This means that the machine is used continuously during operation hours without any preventative maintenance. When the stapler eventually fails—it jams up, parts wear out, etc.—production continues with the other machines while the broken machine is either repaired or replaced.

This approach saves your maintenance team time because they don't need to inspect or perform preventive maintenance on the stapling machine. It's more cost-effective to simply run the machine to failure and deal with problems when they arise, given the easy availability of replacements and the non-critical role of the machine in the overall production process.

What are the advantages of run-to-failure maintenance?

Run-to-failure (RTF) maintenance can have several advantages in specific contexts:

• Lower upfront costs: RTF maintenance usually incurs lower upfront costs compared to preventive maintenance as no action is taken until a failure occurs.
• Simplicity: It's a straightforward strategy to implement, as no planning or scheduling of maintenance activities is necessary until equipment fails.
• Full utilization: Equipment is used to its maximum, potentially extending its useful life beyond what might be achieved with other maintenance strategies.
• No over-maintenance: With RTF, there's no risk of over-maintaining equipment, which can occur in preventive maintenance if the maintenance is performed more frequently than needed.

What are the challenges of run-to-failure maintenance?

Run-to-failure (RFT) maintenance might be suitable for non-critical equipment where the costs of preventive maintenance or the replacement cost of the equipment outweigh the implications of its failure. However, there are several challenges associated with RTF:

• Unpredictable downtime: One of the most obvious disadvantages is the unpredictability of equipment failures, which can lead to unexpected downtimes. This can be disruptive, especially if the failed equipment is part of a critical process.
• Higher repair costs: The cost of emergency repairs can be significantly higher than planned maintenance. This includes costs for expedited spare parts, overtime labor, and potential secondary damages that can occur from a failure.
• Reduced equipment life: Running equipment to failure can often lead to more severe damage than if the problem was detected and corrected earlier. This can shorten the overall lifespan of the equipment.
• Safety concerns: Equipment failures can pose safety risks. If a piece of equipment breaks down unexpectedly, it can cause accidents or harm to the operators and other workers.

When should a run-to-failure maintenance program be used?

A run-to-failure (RTF) maintenance program should be used cautiously and only under certain conditions. It's typically best suited to the following situations:

• Non-critical equipment: RTF is most appropriate for non-critical equipment or systems that do not directly impact the operation's productivity, safety, or bottom line. If these components fail, they should not cause any significant downtime or disruption to operations.
• Low cost of failure: RTF can be a good approach when the cost of failure (including repair or replacement costs and any costs associated with downtime) is less than what preventive maintenance would cost.
• Equipment with a random failure pattern: If the equipment's failure patterns are completely random and not age-related, then preventive maintenance may not be effective, making RTF a more suitable strategy.
• Low safety risks: Equipment that, if failed, does not create a significant safety hazard, can be considered for an RTF approach.
• Non-repairable items: Certain items, like light bulbs, typically run to failure because it's not practical to repair them.

It's important to conduct a risk assessment before choosing an RTF maintenance strategy to ensure that any potential impacts of equipment failure, such as impacts on safety, productivity, and costs, are thoroughly understood and acceptable.

How to effectively implement and monitor run-to-failure maintenance

Run-to-failure maintenance may be implemented and monitored using many maintenance methods. If an entire facility works on a run-to-failure strategy, then CMMS and EAM systems will provide much more functionality than required.

For facilities where run-to-failure is used for some assets and more complex strategies, the CMMS and EAM will allow these different types of maintenance strategies to happen simultaneously. A CMMS can also be useful for tracking the number of times the asset has been repaired or replaced and associated costs. A good run-to-failure maintenance strategy will require a management tool because of the large number of spare parts that may be needed for breakdowns.

Step by step to make run-to-failure part of your maintenance strategy (opens in new tab)

A run-to-failure checklist for maintenance teams

A run-to-failure (RTF) maintenance program or strategy allows you to run equipment until it fails, and then you repair or replace it. Here's a brief checklist for you to follow for an effective RTF program:

1. Equipment selection:
   • Identify and select equipment where run-to-failure is appropriate.
   • Ensure the equipment's failure won't pose safety risks.
   • Confirm that downtime of the equipment doesn't result in significant operational or financial impact.
2. Documentation and data collection:
   • Document the equipment’s details, specs, and history.
   • Establish a method for operators and maintenance personnel to record any observed anomalies or performance degradations.
3. Safety:
   • Train operators to safely shut down the equipment when failure occurs or when failure symptoms are evident.
   • Ensure safety procedures are in place to handle equipment failures without risking personnel or the environment.
4. Stock spare parts:
   • Based on the anticipated type of failures, keep critical spare parts in inventory.
   • Periodically review the inventory of spares to ensure availability when required.
5. Rapid response plan:
   • Develop a plan for rapid response to equipment failures.
   • Train maintenance teams on the specifics of repairing or replacing failed equipment.
6. Failure analysis:
   • When equipment fails, conduct a root cause analysis to understand the reasons behind the failure.
   • Use this analysis to improve processes, operator training, or even reconsider if RTF is appropriate for this equipment.
7. Cost tracking:
   • Track the costs associated with failures, including repairs, downtime, and lost production.
   • Periodically compare these costs with what preventive or predictive maintenance would cost.
8. Review and adapt:
   • Regularly review the RTF program to see if it's meeting the organization's objectives.
   • Consider switching to preventive or predictive maintenance if RTF is not cost-effective or if the operational risks become unacceptable.