What is OEE?
Overall Equipment Effectiveness (OEE) is a total measure of performance that relates the availability of the process to the productivity and quality
What does that mean?
OEE is a Key Performance Indicator (KPI) that can measure the impact of change on a process caused by eliminating process, or equipment losses.
Whay is OEE so important?
If you were told that your department was running flat out you might reasonably assume that the equipment was running efficiently and effectively.
What if the equipment only ran for 75% of the time?
What if when it ran it ran at 80% of its speed ?
What if only 90% of the parts it made are good?
Individually these performance measures seem to indicate an OK piece of equipment, but is it a true picture?
What’s impacting on these performance figures?
How do I measure OEE?
OEE = AVAILABILITY x PRODUCTIVITY x QUALITY
OEE and the 6 Big Losses
“The percentage of time equipment is actually running when we need it”
AVAILABILITY= AVAILABLE TIME – UNPLANNED DOWNTIME x 100% / AVAILABLE TIME
Available Time = Total Available Time – Planned Downtime*
Planned vs unplanned downtime
- Excess capacity.
- Planned breaks.
- Planned Maintenance.
- Communications briefs / team meetings.
Unplanned (Losses) :
- Set Ups and Adjustments.
- Late deliveries (material).
- Operator availability.
“The difference between the potential output and actual output, when the equipment was available”
PRODUCTIVITY = IDEAL CYCLE TIME x ACTUAL OUTPUT* x 100% / AVAILABLE OPERATING TIME
Operating Speed vs Productivity
Operating Speed Rate :
- The % of actual cycle time against ideal cycle time.
- The Operating Speed Rate factored with interruptions to constant processing, i.e. idling and minor stoppages.
“The total good parts produced expressed as a % of the total parts produced”
QUALITY= PARTS MADE – DEFECT QUANTITY x 100% / PARTS MADE
Processed versus Defect Quantity
Parts Made :
The total quantity of parts produced in the available time.
Defect Quantity :
The quantity of parts that did not meet the required standard (including rework) in the available time.