Category: Reliability Analysis

  • What is PM?

    PM is a general term that encompasses all forms of pro-active maintenance including: scheduled overhaul scheduled inspections (CBM) CBM is the prominent form of maintenance today. Although all scheduled activities are called “PM” (for example, in the CMMS or EAM), they are predominantly CBM activities (inspections) performed, often, at the same time as scheduled service…

  • RCM vs RA

    Is RCM a form of Reliability Analysis (RA)? RA is the counting of failure and suspension events in order to understand the behavior pattern of  a component or failure mode. RCM practitioners sometimes refer to the Reliability Centered Maintenance (RCM) process as “reliability analysis”. However, this is confusing. RCM Analysis (as opposed to RA), precisely…

  • Purpose of RA

    The purpose of reliability analysis (RA) is to build, assess the performance of, and continually improve maintenance policies. By a “maintenance policy” we mean a rule or process to be used for decision support. Why do we need policies? We need them because it would be inefficient to always have to evaluate repetitive maintenance situations…

  • TBM or CBM?

    In a fleet of over one hundred units there are four spare engines.  Should an age based overhaul policy be used? Scheduling overhaul based on age seems appropriate due to the need to level the load in the engine rebuild shop. Given the expected failure rate, a rebuild interval of, say 10000 hours, and a…

  • What’s the right data?

    Most meetings or conversation about quantifiable reliability improvement usually end up in a discussion of data and how bad it is. How do we navigate around this impasse? It does seem as though most maintenance discussions, whether in formal meetings or in the corridor, include a frustrated restatement of the inadequacy of data. Why are…