Reliability Assessment through MTBF, MTTR and Availability in Industrial Wood Chippers: A Case Study

Abstract

Given the need to produce products such as paper, pellets, biomass, and other wood-derived materials in the form of chips, it is essential that key equipment, particularly wood chippers, operate reliably and efficiently. In this context, the present study aims to analyze the reliability and performance of two wood chippers operating continuously in an industrial unit over a twelve-month period. The methodology was based on the analysis of historical maintenance records and the application of classical performance indicators, namely Mean Time Between Failures (MTBF), Mean Time To Repair (MTTR), and Availability. In parallel, statistical analysis tools, such as the Weibull distribution, were used to characterize failure regimes, while the Kaplan–Meier estimator was applied to evaluate the empirical survival function of the equipment. The results obtained reveal high levels of operational availability, ranging between 92% and 97%, with MTBF varying between 38 and 105 operating hours. Failure analysis identified the most impactful failure modes, highlighting blade replacement and jamming events as the main causes of downtime. Based on the obtained results, operational improvements and preventive and condition-based maintenance strategies were proposed, aiming to increase reliability, reduce unplanned downtime, and improve the overall efficiency of the wood-chip production process.   Article history: Received (August 5, 2025); Revised (May 24, 2026); Accepted (June 24, 2026); Published online (October 1, 2026)