Introduction to OEE
Over the years there have been many methods used for measuring the efficiency of packaging equipment and complete packaging lines. Let’s face it, everyone wants to improve their processes and see where improvements can be made, but it isn’t always clear where to start.
This is where the concept of Overall Equipment Effectiveness (OEE) comes into play. OEE is a systematic method of measuring the effectiveness of both individual packaging machines and complete lines.
OEE is by no means a new idea. It was introduced way back in the 1960’s as a means of determining how effectively a manufacturing process was being utilized. At ID Technology, our labeling, coding and marking systems are important parts of our customer’s packaging lines and we find that OEE is coming up in conversations more and more frequently.
OEE uses defined measurable factors to calculate the efficiency of the packaging (and a lot other processes too) process. In a perfect world, there would be zero unplanned downtime, equipment would happily run forever at maximum speed (using perfect packaging materials of course!) and it would be unknown for us to every produce product with even a hint of a defect.
Since we have to make do with operating in the real world, the OEE concept gives us an advantage when it comes to managing and improving our packaging processes.
In putting together this introduction to OEE, I’m hugely in debt to the great oee.com website which provided a lot of the ideas and data. That site is a super OEE resource and I encourage everyone with an interest in the topic to check it out.
One of the key features of the OEE concept is its simplicity. OEE is calculated using just three key factors, Availability, Performance and Quality:
Planned Production Time
This is the starting point for OEE. It is the total time available for production and does not include any planned downtime, such as breaks or PMs. The role of OEE is to help eliminate any factors that stop or reduce planned production. These factors are generally referred to as “losses” and include Downtime Loss, Speed Loss and Quality Loss.
Availability takes Downtime Loss in account. Downtime Loss includes all the issues that cause the equipment to stop for a measurable amount of time. This can include many items such as:
- Equipment breakdown
- Lack of materials
Operating Time is the remaining time after the Downtime Loss has been removed from Planned Production Time.
Availability is defined as the ratio of Operating Time to Planned Production Time.
The Performance factor takes Speed Loss into account. This includes factors that cause the equipment to run at less than i’s maximum speed.
Examples of Speed Loss factors include:
- Low quality packaging materials
- Poor equipment condition
- Operator problems
After taking Speed Loss into account, what remains is Net Operating Time
Performance is defined as the ratio of Net Operating Time to Operating Time.
Quality takes into account Quality Loss. This accounts for items produced that fail to meet the required standard, including items that have to be reworked.
After taking Quality Loss into account, the remaining time is Fully Productive Time
Quality is the ratio of Fully Productive Time to Net Operating Time. dividing the number of good products by the total number of products gives the same ration and might be easier to calculate.
To calculate the OEE over a period of time is actually quite simple:
OEE = Availability x Performance x Quality
Let’s take a look at calculating OEE for a sample shift:
|Planned Production Time||= Total Time – Breaks|
|= 410 minutes|
|Operating Time||= Planned Production Time – Downtime|
|= 380 minutes|
|Good Items||= Total Items – Rejects|
|= 30395 – 1232|
|Availability||= Operating Time/Planned Production Time|
|Performance||= (Total Pieces/Operating Time)/Machine Run Rate|
|Quality||= Good Items/Total Items|
|OEE||= Availability x Performance x Quality|
|= 0.927 x 0.8 x 0.96|
|= 0.712 (71.2%)|
If my process was working with complete effectiveness, the OEE would be 100 – mine is closer to 70% and I can see that working on my machine’s Availability (why was there 30 minutes of unplanned downtime?) and Performance (clearly my machine was running at less than its optimum run rate during the shift)
By calculating OEE for equipment and lines over a period of time, areas of reduced effectiveness are highlighted so that improvements can be made. If you are just starting to implement OEE, a good place to start is with the piece of equipment that is the bottleneck on your line. What shows up as the factor that reduces the OEE the most? What can you change to improve it?
ProMach Performance Services – ZPI
While the OEE factors can be calculated manually, this is also a process that can be automated. Here at ProMach we have developed ZPI, a data collection and analysis solution for ProMach (and other) packaging equipment brands that allows a lot of production and equipment and production data to be captured in real-time from just about anywhere.
This solution automatically captures the OEE factor data and calculates, displays and saves OEE results. This is a great solution for businesses operating in a lean manufacturing environment, providing actionable data to enable continuous improvement to packaging processes. OEE can be a Key Performance Indicator (KPI) in a continuous improvement system.
ID Technology, along with the other ProMach companies, is dedicated to working with our customers to ensure their packaging processes run as efficiently as possible
Want to get started with improving your packaging processes? Call ID Technology toll free at: 888-438-3242 Option#3 or you can contact me directly at firstname.lastname@example.org We’ll get you in touch with one of our ID Technology or ProMach Performance specialists, right in your area.