Reliability & Maintenance: What’s the Difference?

Reliability and maintenance are closely intertwined, so much so that there’s even a practice known as reliability-centered maintenance. Yet, the two concepts are distinctly different as well.

In short, maintenance refers to the actions we take to upkeep and repair equipment properly, preventing breakdowns when possible and fixing them when they do occur. This endeavor takes both a proactive and reactive approach and is vital in minimizing unnecessary work cessations and prolonging the life of assets and equipment. 

Reliability, on the other hand, describes the capability of a mechanical system, piece of equipment or process to dependably carry out its intended function without failure over time. It’s an invaluable attribute in manufacturing, engineering and maintenance operations since it directly drives production, efficiency and a company’s bottom line.

Picture a massive thrill ride at a huge theme park. Its design and overall durability would comprise its reliability (and safety) for its numerous daily riders, while maintenance would be applied to make sure it ran consistently well for as long as possible without costly (and possibly dangerous) breakdowns. 

What Is Maintenance?

There are numerous types of maintenance practices, but in an industrial sense, it is essentially divided into three different categories:

Reactive Maintenance

Reactive maintenance is seen as the least-effective approach but can be a necessity due to a shortage of maintenance funds or pressing time constraints. It more or less involves waiting until equipment has failed or revealed evident signs of wear and tear or serious malfunction. 

This type of maintenance is often unplanned and can result in longer downtime and higher immediate maintenance costs due to emergency repairs. While it might be appealing because it doesn’t require a set maintenance process for upkeep and inspection, it is also unpredictable and can cause more disruptions to your operations.

Preventive Maintenance

Preventive maintenance is a planned approach that incorporates systematic, scheduled maintenance tasks with the intent of avoiding equipment issues before they even take place. This can involve everything from scheduled parts replacement to cleaning and lubrication. Other elements of the preventive approach are frequent equipment inspections, plus calibrating machinery to help it run smoothly and operate at the optimal settings for the current job duress. 

Helping ensure compliance is another bonus of the preventive approach, as numerous industries include regulations and standards necessitating regular maintenance of equipment. One potential negative of preventive maintenance is that it requires a set maintenance program and budget and could lead to over maintenance.

Predictive Maintenance

Predictive maintenance is another proactive strategy, one that employs ample technology, data and sophisticated monitoring tools to anticipate when equipment failure may occur. Using data collected from sensors and monitoring systems installed on equipment — such as temperature, vibration, noise levels — predictive strategies can gauge the health of the equipment and foresee in advance when upkeep and parts replacement will be needed. 

One big positive of this data-driven approach is the continuous improvements spurred by knowing your equipment’s maintenance needs more and more as time goes on. Safety and staff wellbeing is another welcome attribute of predictive maintenance, as predicting problems before they occur will reduce accident risk. 

What Is Reliability?

As stated earlier, reliability in a general sense describes the ability of equipment and/or systems to perform their intended functions without failure, under specified conditions on a consistent basis for a set period of time. 

In a more formal and technical sense, reliability can also be seen as a key performance indicator (KPI) illustrating how good your maintenance strategy is at ensuring equipment efficiency and minimal unplanned downtime. In fact, maintenance leaders and others in the field use their own key set of four metrics to determine exactly how reliable a piece of equipment or machinery is. These include:

Mean Time Between Failure (MTBF) 

MTBF is a vital benchmark particularly used in the manufacturing industry and aims to examine the time between operational failures.

• Calculation: MTBF is calculated by the overall length of time a specific system has been in operation divided by the number of breakdowns in that period.
• Pro: When working optimally, the approach helps in planning maintenance and upkeep before an expected breakdown.
• Con: Some see the measurement as overly simplistic and lacking key details; for example, a system that had some early failures but has run smoothly for a year would not have that taken into account solely through MTBF.

Mean Time to Failure (MTTF) 

MTTF is another important data point, but it’s specifically applied to equipment and tools that must be replaced rather than repaired upon failure (batteries and lightbulbs are two great examples). 

• Calculation: MTTF is calculated by measuring the overall length of time a specific system has been in operation divided by the number of assets in use, and it’s used for equipment being replaced.
• Pros: MTTF is a boost to lifespan planning for key non-repairable resources, which in turn assists in cost savings as maintenance leaders will know just how long these assets will run efficiently. 
• Cons: MTTF is an inexact gauge that doesn’t take specific working environments into account and is also limited in its application, as it only refers to one-time-use items.

Availability 

Availability is simply the proportion of time a system is functioning properly (i.e., machine uptime) compared to its overall potential functioning time (which includes both its uptime and downtime). There are also specific subcategories of availability, including Inherent Availability (Ai), which excludes external factors; Achieved Availability (Aa), which factors in the time invested in preventive maintenance; and Operational Availability (Ao), which takes into account any and all elements influencing a system’s availability, even administrative factors.

• Calculation: Availability in a general sense is determined by dividing equipment’s uptime by the total of its uptime and downtime.
• Pro: Availability provides a solid complete overview of asset performance and trustworthiness and helps guide future maintenance planning.
• Con: While availability is a valuable metric when examining a system, it tends to focus on the big picture rather than addressing the root causes and severity of performance issues. 

Reliability 

Asset reliability is a multifaceted measurement that looks at a number of factors, including the aforementioned MTBF and MTTF rates. 

• Calculation: In addition to the MTBF and MTTF calculations, reliability can be calculated by an overall failure rate, which simply divides the number of failures into a specified unit of time (such as a day). 
• Pro: Focusing on reliability as a measurement is a solid bottom-line approach to determining how smooth a system will run over a prolonged period of time. 
• Con: Overemphasizing the importance of reliability can overlook other key factors, such as a system’s operating cost and ease of use. 

To gain a better understanding of some of these constructs, it’s prudent to look into the concept known as RAM, the interplay of Reliability, Availability and Maintainability. 

5 Components of Reliability & Maintenance

While analyzing reliability and maintenance, it’s important to note the crossover between the two concepts as they often do go hand-in-hand. Here are five components that factor strongly into both subjects.

• Asset management: This is the organized practice of developing, conducting, maintaining and improving assets in a cost-effective manner. It aids both the reliability and maintenance of equipment and machinery.
• Business processes: These are strategies that support maintenance procedures and are driven by the innate reliability of a system or piece of equipment. For example, a high-quality, durable HVAC system may not require the same intensive level of upkeep as a poorer one. 
• Workforce management: Key to both reliability and maintenance, well-trained and wisely allocated personnel will conduct upkeep more effectively, minimizing downtime and boosting system reliability. 
• Materials management: When done properly, materials management can greatly optimize maintenance tasks, as it ensures that the right parts are handy for repairs and upkeep when needed. Similarly, by stocking high-quality spare parts, a system’s reliability is also improved. 
• Performance management: This is a vital driver of both concepts, as it analyzes the effectiveness of maintenance efforts and their impact on system reliability. 

Example of Maintenance vs. Reliability

Picture a crucial physical asset to your manufacturing process. It has an engine that requires oil changes every 1,000 hours of use, and the oil change activity is part of its maintenance strategy. Other basic examples of maintenance activity include:

• Scheduled inspections: Regular checks for wear and tear to gauge the health of your equipment and machinery.
• Lubrication and cleaning: Scheduled lubrication of gears and other moving parts as well as removing dust and debris to ensure optimal equipment performance.
• Repairs: Fixing equipment when it breaks down or underperforms; ideally done promptly to avoid downtime and reduced production.
• Upgrades: Replacing old parts with newer, more efficient components; optimally done before they wear out entirely and cause a breakdown.

Reliability, however, describes the capacity for this machine to perform its designated purpose without failure over time. It is mainly premised on how dependable and durable the equipment is under normal operating conditions. Thus, a reliable piece of machinery is one that doesn’t break down often or without warning. So, if the same factory machine has functioned for 10,000 hours without any severe problems, then it’s considered reliable since it consistently performs as needed without requiring breakdown maintenance.

How to Improve Reliability

So how can facility managers and maintenance leaders boost equipment reliability? There are probably hundreds of ways to do so, but here are some key ways to make the most impact:

• Purchase quality equipment and parts: High-quality machinery is innately reliable and normally requires less maintenance and care than its poorly constructed counterparts. 
• Create standardized repair processes. There’s no substitute for consistent, regular repair and upkeep — and, luckily, for today’s maintenance leaders there are easy-to-use software solutions that store standard operating procedures and checklists to ensure maintenance work is always performed the same way.
• Train maintenance teams properly: Even the highest-quality equipment and machinery needs the right human touch, so a well-informed and trained maintenance team is vital to keeping operations running smoothly.
• Improve availability and accessibility of parts: Better parts inventory management means better maintenance and, therefore, more reliable machinery. Having the right part handy when you need it is key to avoiding unnecessary downtime. 
• Use preventive and predictive maintenance strategies: Proactive maintenance strategies will keep you ahead of the game rather than scrambling to play catch-up during sudden and unexpected breakdowns. 
• Implement a CMMS: A computerized maintenance management system (CMMS) puts a wealth of vital data at your fingertips, even when on the go, and makes it easier than ever to boost reliability and maintenance in an organized fashion.

Using a CMMS to Improve Reliability & Maintenance

A CMMS software like Coast can instantly improve your reliability-focused maintenance efforts in a number of ways. Here are some of the most significant examples: 

• Asset management and tracking: A CMMS assists greatly in tracking asset location, history and operational metrics instantaneously. This improves asset lifecycle as well as execution.
• Maintenance scheduling: By automating preventive maintenance schedules, maintenance teams are always on top of machinery upkeep and repair before breakdowns take place, extending equipment lifespan and lessening unpredictable downtime.
• Team communication: Communication is improved greatly by centralizing information and messaging into a CMMS, not to mention the various collaboration tools, real-time notifications and mobile accessibility of this vital resource.
• Reporting and analytics: A real strength of a high-quality CMMS, real-time equipment data assists teams in pinpointing possible areas of improvement, learning from key performance indicators (KPIs) and forming data-driven assessments.

Coast stands out from other CMMS solutions in numerous ways, including the chance to give it a test run via its robust free plan. For those moving forward with a paid plan, Coast offers far more bang for your buck than other platforms, highlighted by its dynamic communication tools as well as easy asset management, work order tracking and countless other smart tools for maintenance oversight. Coast even assists with your CMMS decision-making process by providing clear-cut comparison charts measuring their offerings versus the competition.