What is overall equipment effectiveness (OEE) in manufacturing?

Overall equipment effectiveness, generally referred to as OEE, is the primary way of measuring productivity in process manufacturing plants.

OEE is measured in percentage terms, so an item of equipment with an OEE score of 100% is always available without any unplanned downtime; delivers product as fast as possible; and the product is consistently of good quality.

OEE plays a key role in achieving lean production goals.

How does OEE help process manufacturing plants?

Process plants use OEE to help them consistently improve plant efficiency and productivity. OEE is a key baseline metric for process plant managers to track progress, eliminate waste, and identify losses within the complex workings of a process plant.

With the help of OEE metrics, plant employees can identify assets that are underperforming and investigate the cause. OEE ratings can also be used as a benchmark for comparison against industry standards, other plant assets, or various periods of operation.

OEE is mainly used to reduce what’s known as the six big losses:

  • Equipment failure
  • Equipment setup and adjustments
  • Idling and minor stops
  • Slow production
  • Process defects
  • Reduced yield

What are the best ways to measure OEE?

The preferred way to calculate OEE is by tracking 3 metrics:

  • Availability
  • Performance
  • Quality

Availability means the amount of time that an asset is available compared with planned production time. It includes both planned and unplanned downtime.

Performance considers everything that might slow down the production process, including slower production speed and shortstops between cycles. An asset with a performance score of 100% is running as fast as possible.

Quality allows for defects in the product, pieces that need to be reworked later, and completed pieces that don’t meet the quality standards.

OEE requires combining all 3 metrics to produce a single OEE calculation.

What are the benefits of OEE in manufacturing?

As a key benchmark and baseline for measuring efficiency and productivity, OEE helps process manufacturing plants reach their lean production goals. With the help of OEE metrics, process plants can boost revenue and increase profitability.