There’s not a foolproof maintenance strategy that works for everyone. That makes way for a string of approaches, including condition-based maintenance, reliability centred maintenance (RCM), and total productive maintenance (TPM). Risk-based maintenance (RbM) is yet another take. Could it be the right one for you?
Definition of risk-based maintenance
Risk-based maintenance defines priorities based on risks and on the consequences of failures. Assets that carry the most risk receive the bulk of resources and take precedence over non-critical ones. Because it is based on risk assessment and criticality analysis, it is often compared to RCM.
Is risk-based maintenance the right strategy for you?
Who can benefit from risk-based maintenance? Technically, everyone. In the real world, there are three scenarios where it can be particularly useful. Let’s take a closer look at each of them:
Your company/ plant/ infrastructure relies on highly expensive machinery
When you have a large and expensive asset portfolio, prioritise. Instead of trying to be everywhere at the same time – and failing miserably – decide which assets deserve the most attention. Focus on expensive assets that are hard to replace, which extends the asset’s useful life, improves ROI on investment, and saves money on repairs.
In manufacturing, RCM is also a common strategy to achieve reliability, avoiding downtime and keeping costs down. However, RCM and RbM are not the same. Read up on the differences between risk-based based maintenance vs. reliability centred maintenance.
It’s the first time you are seriously thinking about a maintenance plan
If it is the first time you are thinking about a long-term maintenance plan, welcome! It must look very confusing now, but we promise it isn’t so hard. (Especially if you have the right software, and that’s an unbiased view.) Risk-based maintenance is a good place to start.
Which assets would cause the biggest losses, if broken? Which ones would be the hardest to repair? Even if you’re at a loss with technical aspects, we are willing to bet you know the answers. That will give you an idea of which assets to prioritise in your first maintenance plan.
You have to manage limited resources for maintenance and repairs
Good intentions only go so far. You may have every intention of following a strict preventive plan to avoid breakdowns. But if you keep falling behind schedule, risking lengthy breakdowns and people’s safety, it’s time to change. Under budgeted departments have to prioritise.
Risk-based maintenance is a way to figure out the most economical use of time, money, and human resources. Sure, this means some tasks will fall through the cracks. However, you will minimise risks and protect the company.
Quick recap: the benefits of risk-based maintenance
Based on what we covered so far, these are the benefits of a risk-based strategy:
✔️ Reduces risks to acceptable levels
✔️ Improves safety and reliability
✔️ Extends assets’ useful lives
✔️ Provides guidance for limited budgets
✔️ Eliminates low-value work orders
✔️ It’s a straight-forward approach
Implementing a risk-based maintenance plan 101
1. The first step is risk assessment, which itself comes into two parts:
A. Assess the probability of failure (based on how old the asset is, the bathtub curve, the amount of failures over the last few months/years, and whether it is exposed to humidity or dust). If you have maintenance logs, they will be useful.
B. Assess the consequences of failure (safety hazards, production losses, impact on environment, and impact on company reputation). Score them from 0 to 4 to make a criticality ranking or use our asset criticality calculator.
Assets with greater criticality and likelihood of failure are a priority. There will be regular inspections and an individual maintenance plan, so as to contain the risk. Run a Failure Modes and Effect Analysis to decide which failure modes you need to address in your maintenance plan.
Assets with lower risk will have minimised maintenance plans or no plan at all (run to failure). Change, lubricate and clean parts according to the manufacturer’s recommendations and promote operator care. If they learn basic maintenance, skilled technicians are freer for high-risk assets.
2. The second step is maintenance planning. Prepare a time-based preventive maintenance plan, and allocate teams and inventory to each task. (You can also use condition monitoring and predictive maintenance, if your budget allows. Learn the 4 magical questions to choose the right maintenance strategy for you.)
A note about inventory. You will also need to procure parts for corrective maintenance. To reduce costs, it’s a good idea to keep minimum stocks on site. Here are a few tips for risk- based inventory management:
(1) store spare parts for critical assets, albeit at low amounts if they are rarely used;
(2) keep parts that are used very often on site, regardless of asset criticality;
(3) parts that are not frequently used, but have high lead times, for medium-level assets.
3. Then, the third step is review and improve. Monitor your schedule compliance, the MTBF and MTTR, and downtime. Based on those key performance indicators, assess the effectiveness of your strategy, reevaluate the likelihood of failure, and improve.
Now you know what RbM is, when it should be applied, its benefits, and how to plan for it. Do you think it’s the right strategy for you?
👨💻 If so, schedule a call with one of our specialists to understand how an Intelligent Maintenance Management Platform can help. See how you can monitor each asset, plan and schedule tasks, track KPIs, make audits and so much more with the power of AI.
