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Data-Driven Study of Mass Transit Maintenance

SRE Ottawa recently conducted its event#337 on February 23, 2022. During the meeting, we had the pleasure to welcome Regis Alencar, Senior Reliability Engineer, Toronto Transit Commission (TTC) who spoke on the topic of "Reliability & Maintainability Strategies for Repairable Systems in a Mass Transit Rolling Stock Subway".

Regis' talk pertained to the different maintenance strategies applicable to a repairable system and it summarized the results of an internal study that was conducted in TTC. Mass Transit Systems are complex electro-mechanical systems and having an optimized maintenance strategy to repair/replace components will save the organization millions. There are also other prime reasons to think about the maintenance of these systems: Safety and Customer Satisfaction. If a subway car has a failure inside a tunnel, then the resulting safety hazard is very risky and litigious. Many a number of people can relate to the displeasure of a delayed bus during the morning commute. In order to avoid these kinds of incidents, the Maintenance personnel and Reliability Engineers at the organization will have to develop a maintenance strategy.

A common framework used in developing maintenance strategy is the Reliability-Centered Maintenance (RCM). Originally conceived to be used in aircraft maintenance, the framework defines 6 different types of component failure patterns in a system. The Failure Rate of a component is dependent on its design, usage, and conditions. It can increase or decrease or stay constant over time. RCM's original paper conducted a field study using the maintenance records of aircraft and published the ratio of components exhibiting each of the 6 failure patterns. The result was about ~89% of the failures exhibited non-age-related patterns. Since this study was on aircraft components under defined conditions, one cannot use this result to develop a maintenance plan. Regis spearheaded the TTC study to determine if TTC's own data support the original RCM study. TTC was blessed with a data structure within the organization that had decades of maintenance records which enabled them to analyze the data. The result of that study was shared at this presentation with engaging discussions.

To view a recording of this webinar, and enjoy other webinars, join SRE Ottawa through our membership.

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