When aiming for higher efficiency in your production processes, you need to utilize a critical metric: machine availability. Machine availability represents the time a machine is actively available for use.
In this article, we take a closer look at the importance of machine availability. We cover how it’s calculated. We also compare it to another closely related metric: machine uptime. We’ll explore the benefits and analyze ways to improve your availability score.
What is Machine Availability?
Machine availability is connected to how efficient and reliable your machinery is within the manufacturing process. Specifically, it’s a percentage of how long the machine can work and produce. It’s an essential component in achieving high efficiency in production.
Availability is a critical pillar of OEE (Overall Equipment Effectiveness). A high availability percentage helps provide a healthy OEE score. A clear sign of efficiency is when machines produce output for a significant amount of their total operating time.
Start tracking your OEE
Optimize your production efficiency with Evocon's 30-day free trial.
However, machine availability also considers downtime in its score. Just because a machine is available doesn’t mean it will be producing. It might need repairs or cleaning. Operators may be on a break or swapping shifts. A changeover might be required. A high availability score requires you to emerge victorious in a tug-of-war between machine downtime and uptime.
How to Calculate Machine Availability
As we already discussed, calculating machine availability requires us to know a machine’s scheduled working time. We must also set the given timeframe for this working period.
Once we have decided on a timeframe (a shift, for example), we determine how long the machine was operating. We also need to identify all the recorded instances of downtime. This could be planned downtime, like cleaning. It could also be unplanned downtime, like a machine breakdown.
- Identify and capture planned productive time. This is the sum of your scheduled shifts minus planned shutdowns and lack of demand.
- Identify and capture total downtime.
- Downtime % = Total Downtime / Planned Productive Time x 100%
- Availability % = 100% – Downtime % or Availability % = Run Time / Planned Productive Time x 100%
Case Study: TORM Metall
When the Estonian company TORM Metall found that one of their machines was running at only 35% capacity, they realized that change was necessary. TORM turned to production digitization to reduce machine downtime and track any inefficiencies in their production lines.
TORM used OEE software to track all their downtime and the reasons for it. With that data, they could understand the issues more clearly. From there, implementing solutions led the problematic machine to jump to 70% uptime, doubling its capacity.
What is the Difference Between Machine Uptime and Machine Availability?
Machine uptime and availability are closely related. The terms are used interchangeably and often need to be clarified. However, they’re different metrics with different formulas to help us calculate them.
Machine availability represents planned running time. During a given amount of time, a machine is available for production. This metric includes both uptime and downtime. In other words, if the machine is in a state capable of production, this is its availability. Losses for this metric include any stops, either planned or unplanned downtime.
On the other hand, machine uptime is the total number of hours the machine is working or producing. This metric subtracts any downtime that may affect output. In other words, if the machine runs and produces, this is uptime.
Machine Uptime and Availability: Mr. Evocon at Work
To help us understand the difference further, let’s use an example of Mr. Evocon going to work.
To understand availability, imagine Mr. Evocon works from 9 am – 5 pm five days a week. These hours are his working schedule. Mr. Evocon has booked a holiday in August for two weeks. The company has also scheduled this in the diary. Any breaks for coffee or lunch are also recognized. Mr. Evocon’s working schedule is what we mean by his “availability.”
To represent uptime in this example, we should consider Mr. Evocon as a contractor. He must record every hour so he can get paid. If he wants to take a break or a vacation, Mr. Evocon understands that there won’t be any money coming in. As a contractor, what matters are his actual working hours. These hours reflect his “uptime”.
6 Factors That Affect Equipment Availability
Several factors can affect how much of a machine’s availability is spent working or producing. Issues that lower your availability score are labelled as downtime. There are two types of downtime in manufacturing. Some aspects are planned, such as maintenance. Other factors are more unexpected or unplanned. Below are some factors that can affect machine availability: three planned and three unplanned.
1. Routine maintenance
Ensuring machines are in optimal condition requires regular maintenance. These regular inspections could include cleaning, visual inspections, or other minor routines. These, unfortunately, mean frequent stoppages, which, in turn, affect availability. Yet, these pauses are usually very brief. In the long term, regular maintenance prevents breakdowns. No breakages lead to increased overall efficiency or a higher OEE score.
2. Planned maintenance
To achieve maximum efficiency, scheduling strategic maintenance pauses to allow for checks, adjustments, and repairs is essential. These stops are more comprehensive than regular maintenance. Like routine maintenance, they ensure no future breakdowns, stops that would lead to even more downtime. Using real-time data provided by OEE software can lead to well-calculated, proactive maintenance. This proactive approach ensures less downtime than would have otherwise occurred.
3. Shift changeovers
Changeovers must be planned and executed effectively to ensure high machine availability. Any operating gap between shifts will go towards a lower availability score. You can apply strategies to lessen the impact. Overlapping shifts, for example, ensures that machines are maintained when available. As one shift ends, the new shift could start slightly earlier to allow for a handover of the equipment while avoiding any pause or delay. Cross-training workers makes this even more possible, as employees will have the skills to take over a position when needed, even if it differs from theirs.
4. Material shortages
Any shortage of material will affect machine availability. Maintaining a well-managed supply is vital. Diversifying suppliers, for example, adds further security to maintaining a consistent inventory. It’s also essential to have a safety stock with buffer zones. This added security of stock accounts for changes in demand and supply. Real-time monitoring of your supplies also prepares you for unexpected changes. You can promptly address shortages with increased visibility.
5. Equipment breakdown
Unexpected breakdowns can cause long delays. Not only do technicians have to diagnose and repair the machine, but they could experience a delay while waiting for new parts. Breakdowns cause significant reductions in machine availability. Thus, regular maintenance and inspections are essential, as already mentioned. The use of data and sensors in predictive maintenance through the use of OEE software can also help limit the risks.
6. Unscheduled stops
Other factors can lead to an unscheduled stop alongside unexpected breakdowns or failures. For example, human errors and safety incidents can impact availability. Maintaining high levels of training alongside strict health and safety codes can go a long way in preventing too many unwanted stops.
How to Improve Machine Availability
With predictive maintenance, forming a proactive maintenance culture becomes much more manageable. With this change, overall availability and efficiency can increase. Through installing and utilizing sensors and analytics, maintenance can know if a machine is showing signs of deterioration. Firstly, this prevents a breakdown and a major unexpected stop. Secondly, sensors allow staff to understand the health of a machine without having to stop work, open it up, and look inside.
Streamline changeover processes
During a changeover, equipment could become unavailable. This unavailability could be due to a shift change, swapping material for a different product, or another change that requires a planned stop. By streamlining this process, removing or at least reducing the stoppage is sometimes possible. With the reduction in downtime comes an improvement in machine availability. By implementing a tried and tested technique, you can reduce changeover times. For example, a method such as SMED (Single-minute exchange of die) could increase machine uptime. This lean production technique aims to keep a changeover time to less than 10 minutes (or a single-digit number, hence a single minute).
Install OEE software
As you look to improve machine availability further, OEE software plays a crucial role in achieving those goals. It can empower both people and production through real-time data. Being able to visualize machine status means no surprises. You can spot any issues before they significantly affect machine availability.
On top of that, the software records all downtime, allowing you to categorize it. Once patterns start to emerge, you can take action. Root causes can be discovered and corrected. Unplanned downtime will begin to decrease after implementing the necessary changes.
Track your availability
Harness powerful OEE tools with Evocon’s 30-day free trial.
Optimize process management
Help the machine help you. By providing the machine with everything it needs when it needs it, machine availability will rise. The chances of a stop caused by resource scarcity or resupply decrease, allowing the machine to run longer. It will also produce more efficiently. For this to happen, inventory management schemes are vital. As an example, Just-In-Time principles (JIT) lead to a steady material supply without stockpiling or unnecessary costs. Essentially, you can produce goods according to customer demand. Inventory is explicitly stocked for what you need to make. With less inventory, processes become smoother with faster changeovers. Alongside that, review your standard operating procedures (SOPs). Ensure they are optimized and clear to minimize errors, downtime, and unwanted costs.
OEE Software and Machine Availability
As we have shown, machine availability is vital to any efficient manufacturing process. At the heart of the matter, increased availability and uptime lead to increased efficiency, production, and, crucially, reduced cost.
Evocon’s production monitoring software enables you to monitor the status of your entire shift in real-time. Without waiting for something to go wrong before reacting, teams can handle any issues before they become problematic, increasing your machine availability metric.
With a real-time OEE dashboard, a user is able to create widgets to monitor the KPIs that are most important to them. In the case of machine availability, the downtime summary and production data widgets give you critical information if you’re looking to improve these metrics.
By understanding what went wrong, preventative measures become simple to execute. Spot patterns and trends with historical tracking and make better decisions about what process improvements to make.
In this time usage report, for example, production time is clearly divided between good production (green), slow production (yellow), and downtime (red). The report helps you see clearly if the changes you’re implementing are converting downtime into good production time. This is especially useful for analyzing longer time frames.
Even with the right tools, OEE software’s effectiveness relies on how it’s deployed. Creating a culture around OEE is vital for the whole team to get behind. Continuous improvement is a must. Feedback from every staff member should be encouraged. You should see failures as learning opportunities and a way of improving further. Small steps like these are vital in enhancing your machine availability score and overall equipment effectiveness.