Mean Time Between Failures

What is Mean Time Between Failures?

Mean Time Between Failures (MTBF) is a critical reliability maintenance metric in facilities management services that measures the average time elapsed between one failure and the next during the normal operation of equipment or systems. MTBF is used to predict the reliability and performance of an asset over time, providing facility managers with valuable information for maintenance planning and risk management. A higher MTBF indicates greater reliability and fewer frequent failures, which is desirable for maintaining efficient and uninterrupted facility operations.

Mean Time Between Failures is defined as:

1. The average time interval between non-scheduled (reactive) maintenance or repairs performed on a piece of equipment or system.
2. A statistical measurement of the expected performance of a system is calculated by dividing the total operational time of the equipment by the number of failures that occurred in that period.

What is the MTBF Calculation?

When calculating MTBF, follow these steps:

1. Total operational time: First, add up the total operational time that the equipment or system was running and available for use during the period you are analyzing.
2. Count of failures: Record the total number of times the equipment or system failed during the same period.
3. Calculate MTBF: Divide the total operational time by the number of failures to find the average time between failures.

MTBF Formula: MTBF = Total Operational Time / Number of Failures

Example calculation: If a set of machinery operates for a total of 10,000 hours and experiences 5 failures during that time, the MTBF would be calculated as follows:

• Total Operational Time: 10,000 hours
• Number of Failures: 5

MTBF = 10,000 hours / 5 failures = 2,000 hours

This calculation indicates that, on average, the machinery can run for 2,000 hours before a failure occurs. Understanding MTBF is crucial for predicting the reliability and maintenance needs of equipment, systems, and unplanned downtime.

Implications of Mean Time Between Failures in Facilities Management

The implications of MTBF for service providers and facility managers are the following:

For Service Providers

• Service quality: High MTBF values can be a selling point, indicating the high quality and reliability of the services provided.
• Customer trust: Reliable equipment that functions for longer periods without failure builds customer trust and satisfaction.
• Efficient resource utilization: Service providers can optimize their resource allocation and inventory management based on MTBF data.

For Facility Managers

• Asset management: MTBF is an essential metric for effective asset management, guiding decisions on equipment repair or replacement.
• Operational continuity: By monitoring MTBF, facility managers can implement strategies to ensure operational continuity and reduce the impact of equipment failures.
• Performance metrics: MTBF is often used as a performance metric to measure the effectiveness of the maintenance team and processes.

Mean Time Between Failures (MTBF) is an indispensable metric in Facilities Management. It offers insights into equipment reliability and helps in the strategic planning of maintenance activities. By effectively analyzing and improving MTBF value, facilities can enhance their operational reliability and efficiency. Anticipating machine failure can lead to reduced costs and improved service delivery.

Frequently Asked Questions (FAQs)

Why is Mean Time Between Failures significant in facilities management?

MTBF is significant in facilities management for several reasons:

• Reliability assessment: MTBF serves as a key indicator of the reliability of the facilities’ systems and equipment.
• Maintenance scheduling: This helps in the planning and scheduling of preventive maintenance to minimize the likelihood of unexpected breakdowns.
• Cost management: Understanding MTBF can lead to better cost management by reducing downtime and extending the life of equipment.

What is constant failure rate?

A constant failure rate describes a situation where the probability of a system or component failing remains consistent over time. This rate is typical during the “useful life” phase of a product’s lifecycle, where the performance is expected to be stable under normal conditions. The failure process, modeled by an exponential distribution, suggests that failures are random and independent of the system’s age. Understanding this concept is vital for reliability engineers as it aids in designing reliable systems and effective maintenance strategies.

What types of industries use Mean Time Between Failure?

In industries managing repairable systems, MTBF (Mean Time Between Failure) is crucial for maintaining operational reliability. It’s used in manufacturing, telecommunications, IT, aerospace, automotive, and energy sectors to optimize maintenance, enhance safety, and reduce costs. By predicting equipment failures, these industries can plan proactive repairs, improving system uptime and longevity.

Is MTBF the same as average life?

MTBF (Mean Time Between Failures) and average life (Mean Time To Failure, MTTF) are related but distinct. MTBF applies to repairable systems and measures the average time between failures, indicating reliability and helping plan maintenance. Average life, or MTTF, applies to non-repairable items and indicates the expected lifetime before a system must be replaced, not repaired. Essentially, MTBF is used for systems that can be fixed, while MTTF is for those, that once failed, are replaced.