Overall equipment effectiveness (OEE) is a widely implemented metric that characterizes the performance of a plant, and is expressed as a percentage of the total planned or scheduled production time. OEE essentially measures your plant’s performance in terms of equipment reliability and availability. It is calculated as the product of 3 factors – performance, quality, and availability:
Total Equipment Effective Performance (TEEP) extends OEE by providing insight into plant capacity and utilization by incorporating schedule losses, in the form of an extra term – utilization. Therefore, it can be expressed in terms of OEE as:
TEEP (%) = OEE (%) × Utilization (%)
These two key metrics define the performance efficiency of your plant. In this article, we will discuss how you can utilize a Computer Maintenance Management System (CMMS) to improve your OEE and TEEP and drive your business bottom line. But before we dive right into that, it is important to get re-acquainted with the 4 aforementioned terms that are factored into OEE and TEEP.
Performance is calculated by comparing the ideal and actual production times, or alternatively, can be expressed in terms of production rates:
Quality represents the percentage of produced units that are within acceptable quality standards:
Availability quantifies the actual amount of time that equipment is able to perform its function, compared to the planned duration that it is designed to run.
Utilization is calculated by deducting the idle time from the total available time:
Utilization (%) = (Total available time – Idle time) × 100% / Total available time
The role of CMMS in OEE and TEEP improvement
CMMS acts as the enabler in optimizing your OEE and TEEP by facilitating the management and collection of essential data regarding your plant’s equipment. It directly plays a part in driving up your plant’s Availability and Performance, and can also indirectly improve the Utilization and Quality factors. Below are some of those exact aspects of CMMS:
#1) Categorizing Failure Modes
It is vital to understand why equipment functional failures occur and what the failure modes and effects are. A robust system should be in place to record those failure modes for each downtime event, so that informed corrective action plans can be implemented following root cause analysis. The importance of accurate data in improving asset reliability is paramount, and that is where CMMS bridges the gap. This is critical in being able to maintain a Reliability Centered Maintenance approach towards your assets and their maintenance needs. This is one of the primary means of monitoring and improving the Performance parameter that impacts OEE and inherently TEEP as well.
#2) Tracking Downtime
It would be fairly challenging to tackle the issue of downtime without being able to collect equipment failure history and understanding the underlying trends. For example, there could be seasonal trends to equipment failure, or human performance error trends during holiday seasons or long weekends, etc. Such information allows the business leadership teams to look beyond just the equipment and implement actions to prevent incessant asset failure driven by other nascent factors. Here too, CMMS is an invaluable tool for gathering and analyzing the relevant downtime data. Downtime tracking can help gather valuable data that is critical for improving Availability as well as Utilization.
#3) Planning and Tracking Proactive Maintenance
Proactive maintenance methods in the form of either predictive, or condition-based, maintenance, or preventive maintenance can leverage the advantages of automation through CMMS to minimize downtimes that may arise due to equipment failure. In particular, the role of CMMS in predictive maintenance is indispensable. Maintenance of manufacturing equipment not only impacts the final product and the cycle, hence impacting Quality and Performance but also keeps a check on equipment Availability.
#4) Planning and Tracking Corrective and Deficient Maintenance Work Orders
CMMS can also play its parts in automatically tracking equipment repairs and maintenance and provide detailed work order histories. Similar to proactive maintenance, corrective, and deficient maintenance also impacts Quality, Performance, and Availability.
#5) Centralizing Administration
A centralized database such as CMMS can be used to directly calculate your OEE, TEEP, and other KPIs. A centralized web-based administration enables employees to make quick, informed decisions based on objective data. By centralizing the information, you can create a more effective and engaged organization with a transparent workflow. Centralizing the system glues together the whole initiative towards improving OEE and TEEP.
Monitoring OEE across multiple assets and TEEP over time might sound like a daunting task for most plant managers and owners, and it definitely is if you’re still using legacy methods and not leveraging current technologies. At a time where we are living when CMMS can enable you to access equipment data on your fingertips, it is easier and more important than ever to use OEE and TEEP as an actual instrument towards measuring and driving plant effectiveness.