Visit MTBF (Mean Time Between Failures, or Average time between breakdowns) is a reliability indicator (KPI) which represents the average duration of continuous operation of a piece of equipment or a system before a failure occurs. This is the benchmark KPI used to assess the reliability of non-repairable machines, or the period of good operation between two consecutive breakdowns on a repairable machine.
**In-depth definition:**The MTBF is essential for the Industrial Engineering because it quantifies the robustness and quality of equipment. A high MTBF means that equipment is reliable, reducing unscheduled downtime and, consequently, downtime costs. Corrective Maintenance. It is the main indicator used to plan and justify Preventive Maintenance In this way, teams can schedule replacement or critical inspection operations just before the equipment is statistically due to fail.
The aim of the’Operational Excellence is to continuously increase MTBF through improvement actions based on failure analysis (Root Cause Analysis).
MTBF Calculation and its Meaning
MTBF is calculated by dividing the total uptime of the equipment by the total number of failures during the same period.
Calculation example : An assembly line operates for 400 hours over a month and suffers 4 breakdowns, requiring production to be halted.
Interpretation : The equipment is statistically expected to run for 100 hours before breaking down. This figure is crucial for production planning and load time management.
MTBF in the Continuous Improvement Strategy
Analysis and improvement of MTBF are at the heart of the equipment reliability strategy, directly influencing the TRS (Taux de Rendement Synthétique) :
- Failure Analysis : Each failure contributing to the MTBF calculation must be rigorously analyzed (8D analysis, The 5 Whys) to determine the root cause and implement a permanent solution. These solutions can range from modifying the Standardization adding systems Poka-Yoke or replacement of a weak component Quality (for example, a bearing or Industrial Refractory).
- Design for Reliability : When choosing a new piece of Manufacturing, the MTBF (often specified by the supplier) is a key factor in calculating the ROI (Return on Investment). More expensive equipment with a higher MTBF can be more profitable in the long term by reducing non-production costs (Muda waiting time).
- Internal comparison : Pareto's MTBF analysis helps to identify the most unreliable equipment or components in the plant, and to focus the efforts of the KAIZEN where the gain in reliability will be greatest.
MTBF and MTTR
MTBF is often combined with another indicator, the MTTR (Mean Time To Repair), which measures the average time required to restore equipment to working order after a breakdown. MTBF measures the frequency of breakdowns (reliability), while MTTR measures the speed of repair (maintainability). The combination of the two gives a complete picture of maintenance efficiency.
In conclusion, the MTBF is the fundamental indicator of reliability. By monitoring and improving it, the company invests directly in the stability of its processes and the maximization of its productive time, ensuring Operational Performance higher.