Reliability-centered maintenance (RCM) is a strategy focused on ensuring that assets operate as designed.

Implementing a reliability-centered maintenance program leads to improved reliability/uptime, as well as decreased costs. RCM categorizes equipment according to its potential impact on safety, operations, and/or maintenance budgets. 

These categories provide the context central to RCM. Assets are prioritized so a facility’s largest or most complex don’t automatically garner the most attention and resources, because those assets may not be most important to the bottom line. 

The concept itself was introduced by United Airlines engineers Stanley Nowlan and Howard Heap in a U.S. Department of Defense study in 1978. It called for a shift from the assumption that an asset’s age was the biggest factor in determining how close it was to failure and when it would need replacement. Instead, reliability-centered maintenance highlighted the importance of managing assets based on their condition and criticality.  

The SAE Standard for Reliability-Centered Maintenance can be used by any organization that manages physical assets. RCM goals include evaluating, categorizing, prioritizing, and understanding how to intervene when it comes to the impact of failures. It enhances an organization’s understanding of risk and can improve decision making. 

A successful RCM program helps teams improve their asset uptime and availability because it involves detailed and tailored analysis, rather than treating maintenance as a one-size-fits-all practice. Components include:

• identifying failure modes
• addressing failure modes by importance
• identifying the most-effective maintenance responses for various scenarios.

An RCM program

Several concrete factors determine whether a program can be accurately classified as RCM. These come from SAE International’s A Guide to the Reliability Centered Maintenance (RCM) Standard (SAE JA1012). This clarifies what needs to be addressed to put RCM into practice. The standard has seven guiding questions, including “What are the events that cause each failure?” and “In what way does each failure matter?” 

Implementing RCM can be a complex undertaking. One challenge is identifying the appropriate risk-management strategy for each asset. This may mean allowing specific assets to fail and then replacing them. Or it may mean using condition-monitoring sensors to receive around-the-clock data about asset health to respond before failure occurs.

Another challenge is selecting appropriate tools for each piece of equipment. Vibration monitoring is one common method. The tools involved, depending on the criticality of an asset, can include handheld vibration tools or vibration sensors mounted directly on assets.

Reliability-centered maintenance lets maintenance teams address dominant causes of equipment failure in a strategic and cost-effective manner. EP

John Bernet is Mechanical Application and Product Specialist at Fluke Reliability. For more information, click here.