The main goal of OEE is to reduce or eliminate the so-called Six Big Losses. These are the main factors that cause equipment-related productivity losses in the production process.

Six Big Losses

Availability Losses

A fundamental element of OEE is the availability of machines and systems. Uptime is the time during which a machine or system is up and running and producing. Conversely, downtime is the time when a machine should be running but is not, resulting in financial loss.

Planned Downtime

OEE is reduced by planned events that result in machine downtime. these events include replacements, maintenance, inspections and cleaning. Through the use of specialized software, these planned downtimes can be meticulously analyzed and optimized to minimize their impact, and despite their non-negative nature, there is still a lot of room for improvement.

Unplanned Downtime

When planned production is interrupted by unforeseen events such as failures, downtime, power outages, natural disasters or absenteeism, it is called unplanned downtime. To reduce these ineffective times, the causes need to be accurately tracked, digitally categorized, and analyzed on an ongoing basis to identify weaknesses in the process.

Loss of performance

Another important element of OEE is the performance of machines and systems. This is the ratio of the actual output produced to the theoretical maximum output that can be produced within a specified run time. Loss of performance can result from short interruptions or excessively slow operating speeds.

Short stops

Short stops of less than a minute are caused by tooling problems, programming errors, sensor congestion, or the need for a quick cleanup and are usually resolved by the operator. These interruptions are unnoticeable but can accumulate minutes of unproductive time. Short stops are predictable and can be eliminated or controlled.

Slow Cycles

occur when a machine is running below its potential maximum speed due to age, maintenance, breakdowns, or materials. Unlike a brief stop, production continues in a slow cycle situation, but at a slower rate. If it is not possible to determine ideal run times, management can rely on historical data to determine these times, and conducting adequate research is key to determining them.

Loss of Quality

In OEE, loss of quality is when the quality of a product does not match the expected standard. Compared to the other two types of losses, quality losses have a much greater impact. This is because defective products waste not only material but also production time.

Even if the defective product can be repaired, rework takes up operator and machine resources and hence is also a loss.

Production Scrap

Some problems can only be detected after production has taken place, such as over-packaging, under-packaging, mislabeling or defective packaging. Technical means such as sensors or cameras can greatly alleviate these problems by recognizing quality issues in real time. Together with specialized OEE software, this type of loss is expected to be eliminated in the near future.

Start-up scrap

This type of loss occurs when a machine produces defective products due to instability during startup, setup changes, or product adjustments. Operator expertise is critical in getting the settings right and avoiding repeated trial and error. Automated digital assistance systems can quickly and significantly reduce this type of loss.