Reliability Centred Maintenance (RCM) Explained

Asset Management December 12, 2022

In any business or industry, maximising assets is a priority. However, equipment failures are inevitable, so the next best thing that can be done is to optimise the functional lifespan of critical equipment and machinery through execution of asset maintenance strategies.

For the mining industry and businesses that heavily rely on the use of registerable plant, mobile plant, fixed plant and equipment, downtime can mean losses amounting to millions of dollars. Moreover, failing or failed equipment pose potential health and safety hazards that can lead to accidents and loss of lives. Therefore, development and implementation of efficient and effective maintenance strategies plays a crucial role in minimising downtime and ensuring equipment is working at peak performance.

Reliability centred maintenance (RCM) is one such method, process or system used to identify problems with assets and determine the actions required to ensure they continue to work at maximum capacity.

RCM: Early Beginnings

First used in the aviation industry in the 1960s, reliability centred maintenance was developed to address the alarming crash rates (by today’s standards) among jet aircraft. The US Federal Aviation Administration and United Airlines (UAL) were compelled to devise new ways to improve processes within the aviation industry to prevent equipment failure.

The UAL then conducted a series of intensive engineering studies on in-service aircraft. They discovered that the basic assumption that each aircraft and its parts had a term or lifetime of reliable service, and that it had to be overhauled or replaced after said lifetime or term of serviceability, was erroneous.

Extensive research showed that only 11% of aircraft components suffered from age related failures and the remaining 89% were most likely to fail when they were new or straight after maintenance was performed.

This meant that a large number of equipment failures were not always connected to the age of the asset, and that managing assets based on their specific condition (condition-based monitoring), was crucial.

Thus, RCM was developed as a specialised maintenance process or strategy that considers potential failure mechanisms and how they can affect system performance.

The term RCM was first used in white papers by Stanley Nowlan, Howard Heap, Tom Matteson, and other senior executives and engineers at UAL. It described the process of determining the optimum maintenance requirements for an aircraft. The report titled “Reliability-Centered Maintenance” by Howard Heap and Stanley Nowlan, published in 1978, remains one of the most significant documents in the history of physical asset management and serves as the foundation of RCM.

The concept was subsequently adopted by the US military in the 1970s, followed by the US commercial nuclear power industry in the 1980s. It then began to permeate other commercial industries, including petrochemical, steelmaking, transportation, utilities, manufacturing, and mining in the 1990s.

What Is Reliability Centred Maintenance?

Let’s dive deeper into the meaning of RCM below.

RCM Meaning and Definition

The basic definition of reliability-centred maintenance is “the action taken to protect, preserve, or restore the as-built functionality of any facility or system.”

However, this description lacks proactive maintenance, which involves addressing the root cause (RCA) of chronic problems. This approach requires engaging key stakeholders who possess the necessary experience and training to understand the functionality of proactive maintenance.

The key to understanding the definition of RCM lies in the root words that comprise it: reliability centred maintenance.

In order to achieve affordable asset reliability, reliability-centred maintenance essentially offers a roadmap for analysing and addressing the core causes of equipment failures. These come in the form of technology, culture, design, and maintenance strategy inefficiencies.

RCM utilises a number of approaches, including reactive, predictive and preventive maintenance. It also makes use of procedures to uncover latent or hidden failure modes (errors or defects) that pose potential or actual hazards.

While downtime is unavoidable when sophisticated machinery is involved, the mining industry and businesses that depend heavily on plant and equipment employ RCM to prevent unforeseen failures.

Why?

Equipment failure or breakdown requires time-consuming maintenance, expensive outsourcing and replacement costs. It also leads to lost productivity or production delays that will impact both your business and the stakeholders that depend on it.

Benefits and Purpose of RCM

So, what are the advantages of RCM? What is its purpose?

Like any maintenance strategy, the core goal of RCM is to optimise the service reliability of equipment or machinery. However, it aims to do this in the most cost-effective manner by focusing on the maintenance requirements of each asset.

Rather than scheduling maintenance for groups of assets at the same time, RCM focuses on individual assets. Specific details about every single machine, piece of equipment or asset are taken into account to come up with most efficient, appropriate maintenance tasks or schedule.

For the mining industry and owners of complex plant and equipment, reliability-centred maintenance provides several benefits.

• It helps set reasonable expectations. A well-executed RCM program can aid in establishing reasonable expectations for the performance of each asset. It will give you information on the upkeep required over the course of each equipment’s lifetime, enabling you to design an effective maintenance schedule. In exchange, this makes your budgeting efforts realistic and ensures you’re in the lead for preparing future asset replacements that will be required.
• It offers clarity on business risks. A lot of information, particularly regarding risk levels, will be provided by your RCM strategy. This knowledge can be helpful for a number of activities if used properly. In particular, it can assist in determining where your maintenance activities need to be increased or decreased. This is crucial in ensuring that your attention is directed toward the appropriate procedures and machinery. When it comes to larger operations where it is impractical to allocate the same amount of time and money for maintenance on every component of the system, this can have a substantial impact on your time and resources.
• It enhances and maximises asset operating performance. Since the point of RCM is to ensure that only the most efficient form of maintenance is applied for a specific asset, it optimises the asset’s service reliability. It prevents time-consuming, costly and unnecessary maintenance actions from being taken, yet boosts asset performance or functionality in the long-term.
• It aids in managing health, safety, and environmental hazards. RCM poses several advantages related to health and safety in the workplace and improves environmental outcomes. A well designed and implemented RCM program can lessen the carbon footprint of your business and decrease risks to the wellbeing of your employees.
• It results in cost reductions. With RCM, you can avoid overspending on unnecessary maintenance while also preventing expensive breakdowns. It also helps to reduce unnecessary inventory, including both capital equipment and spare parts for maintenance, as well as the cost of maintenance management to address the associated issues. These are the three primary areas where cost savings can be achieved.
• It provides valuable data on quantitative risk reduction. The value of preventive maintenance as part of your RCM framework, can be objectively evaluated by comparing risk reduction to maintenance costs. You can utilise this useful information for a variety of additional analyses.
• It prevents the loss of critical knowledge. RCM mandates the documentation of degradation in any situation, which then facilitates a better understanding of why particular maintenance is required for certain assets. This keeps vital information from being lost and also educates your workforce.
• It enhances relationships with clients, the community and other stakeholders. You can anticipate better connections with your customers, neighbours, and even the government if your maintenance strategy is in line with industry best practice and reflects your company’s mission and vision.
• It promotes confidence, a sense of ownership and teamwork. The data RCM yields promotes an in-depth understanding of assets and the many ways by which they could fail as well as the maintenance they require to perform optimally. Armed with this knowledge, team members can develop confidence and a strong sense of responsibility for the assets under their care. Also, RCM as a practice can promote teamwork and synergy among operations and maintenance teams who know first-hand what they can do to ensure productivity and safety through the efficient maintenance of assets.

RCM Standards

Like any formalised approach to asset maintenance, there are certain RCM standards and principles to adhere to.

Specifically, the RCM method is defined by a number of standards which include:

• IEC 60300.3.11-2011 Dependability Management – Application Guide – Reliability Centred Maintenance; and
• SAE standard JA1011: Evaluation Criteria for Reliability-Centered Maintenance (RCM) Processes.
• ISO 55000 Asset Management – Overview, Principles, and Terminology.
• ISO 55001 Asset Management – Management Systems – Requirements.
• ISO 55002 Guidelines for the Application of ISO 55000

RCM Methodology and Processes

The RCM methodology continuously monitors maintenance tasks that significantly affect performance. All maintenance spending is aimed toward the assurance of quality production.

Equipment availability is kept high, and mines remain open with the help of reliability centred maintenance strategies for mining assets. Every machine harvesting, processing, refining or transporting minerals will need support from a maintenance plan incorporating asset management best practices to assure continued availability as increased demand continues to push production to its limit.

To achieve this, the following seven elements are covered relative to the asset or system under review as part of the structured RCM process:

• Functions: How well it is supposed to run or what it should be able to do at peak performance
• Functional failures: All the possible ways the asset could fail (e.g., fatigue, human error, manufacturing or design flaws or defects, organisational strategy or processes, etc.)
• Failure modes: Refers to the root causes of every possible kind of failure (may be determined through root cause analysis)
• Failure effects: Refers to the effects of the potential failure of said asset
• Failure consequences: The outcome of each failure – these could be safety, finance or productivity related
• Proactive tasks: These are actions or activities that can be carried out to predict or prevent each type of failure
• Default actions: Refer to courses of action when there are no suitable preventive or proactive measures available (e.g., allowing a machine that’s near the end of its functional lifespan to run and ensuring you have a replacement ready when the machine reaches its end of life).

RCM methods and processes can be classified into “Classical RCM”, “Streamlined RCM”, and “PM Optimization”. “Classical RCM” is a labour-intensive program with huge complexities ; although it has benefits, it can be costly and have low success rates. “Streamlined RCM,” also known as modified classical RCM or reliability-based maintenance, is quite similar to classical RCM. The major difference is that Streamlined RCM focuses on pre-screened and evaluated systems deemed important, offering benefits but also incurring high costs. “PM Optimization” is a newer approach, developed from the lessons learned from both Classical and Streamlined RCM methods. It emphasises high craft involvement while retaining many of the Classical RCM techniques. PM Optimisation is a more efficient approach to RCM through risk analysis and can be 1/6 of the cost associated with Classical RCM.

How to Implement an RCM Strategy

The implementation of an RCM strategy typically involves three phases: Decision, Analysis and Action. There are seven questions to answer within these three phases.

Phase 1: Decision

In this phase, you must assess each item on your asset register to ascertain its intended use and potential points of failure.

1. How is the asset supposed to function?

Find out precisely how the asset in question is supposed to work. The purpose of this inquiry is to learn how the asset complies with applicable regulations and standards while directly or indirectly meeting the needs of your business and its clients. To highlight any restrictions, safety issues, and manufacturer-recommended maintenance schedules, consult manufacturer documentation at this step.

2. How might the asset fail or malfunction?

Once you are familiar with an asset’s major and secondary uses, it’s time to record any potential failure modes. Historical data is crucial in this situation. While some of these failure scenarios may be totally speculative, others may have unfortunately already occurred. Examine each possibility in great depth, paying particular attention to whether the asset as a whole or a single component is affected. If the latter, you should also ascertain whether the system as a whole would malfunction if that component were to fail.

3. What could lead to each of these failure modes?

You can now proceed to understanding the ‘why’ after figuring out how an asset can fail. What must fail for each failure mode to happen? The causes could be anything from worn-out machinery, to human error, to environmental conditions. Finding the reasons of each failure mode’s fundamental or root causes is essential to formulating a successful maintenance strategy as it indicates how likely each failure mode is to occur.

Phase 2: Analysis

The RCM process examines the effects of asset failures before creating a maintenance plan that’s specific to the requirements and value of each asset.

4. What happens when a particular failure occurs?

The immediate consequences of asset failure are the main emphasis of the initial analytical stage. What impact does a failure have on total costs, including downtime, repair costs, and more? Will manufacturing be slowed or stopped? What about conceivable product flaws? Your firm will be well-prepared to design an RCM program that minimises downtime and keeps costs low if you ask these and comparable questions, with the answers informed by historical data, solid forecasts, and input from all pertinent stakeholders.

5. What effects does each failure have on your business and how it operates?

The effects of asset failure on your company should then be examined using a broad lens at a deeper level than in the previous stage of the study. Here, issues with safety, the environment, and the state of the asset itself are all relevant. A complete picture of what an asset means to your firm can be obtained by looking at the effects of asset failure beyond cost and production issues.

6. What type of maintenance measure would be most effective for each failure?

You are now prepared to discuss which maintenance practices are most effective for preventing or lessening the impact of each asset failure on your business. The criteria examined above should offer a clear image of how important the asset is to your company, along with the implications and possibility of its failure. The sort of approach you will use will depend greatly on these considerations. Among the possible strategies you can adopt are predictive, condition-based, preventive and reactive maintenance. You can use one of these techniques or a combination of them as part of the most efficient and affordable maintenance strategy for each asset under consideration.

Phase 3: Action

You’ve developed the most reliable reliability-centred maintenance strategy you can by asking the right questions, gathering data, and analysing it.

Implementing it is the last step. As you put your maintenance schedule into action, keep an eye on performance to determine if it meets expectations or if you need to adjust your strategy. At this point, there’s one more query to ask about the assets being monitored.

7. What if there isn’t an appropriate maintenance solution available?

Ideally, your company won’t need to ask this question frequently or at all. However, some assets can’t be served by a reactive maintenance strategy, or with more proactive alternatives. This can happen because of financial constraints, the nature of the asset or its age, or other exceptional conditions like recently enacted legislation. Make the best of the circumstance by taking precautions to lessen the effect on your business should the asset malfunction. This can entail altering processes so the asset eventually becomes unnecessary, keeping a backup asset on hand, or even redesigning the asset to lengthen its useful lifespan or make its maintenance easier.

How do you start?

Begin by assessing the criticality of your assets. In essence, you should ask, ‘How horrible would it be if this asset failed?’ Then begin considering additional issues, such as labour and maintenance costs, accident risk, environmental harm, lost productivity, and compliance-related fines.

Rank your assets from the most to least critical after determining their importance.

Use the seven RCM questions on each asset starting at the top of your list. You can then choose the appropriate maintenance plan or proactive task for each asset based on the answers.

Remember:

• An asset register or mine management system is essential to ensure all assets are covered within your RCM plan.
• All concerned stakeholders, including your operations supervisor, engineering supervisor, plant operator, maintenance team, etc., must be involved for successful RCM implementation.
• Its beneficial to engage a highly experienced and knowledgeable RCM project delivery specialist like AME to ensure your RCM strategy is successfully designed and implemented.

Why Choose AME for Reliability Centred Maintenance

The goal of reliability-centred maintenance is to keep a company’s assets operating as efficiently as possible whilst minimising downtime and unnecessary repair expenses.

However, a successful RCM implementation necessitates a comprehensive maintenance solution that streamlines asset management and centralises asset data for your company. This is exactly what AME accomplishes, enabling your business to precisely identify asset needs and create a successful RCM strategy.

AME offers our customer base a wide variety of robust, simple-to-use solutions for anything and everything – from asset performance management, plant and equipment audits, to maintenance consulting.

Please get in touch with us if you are interested in reviewing or implementing an RCM program in your company.