How to calculate your OEE

OEE (Overall Equipment Effectiveness), is the standard for measuring manufacturing productivity.

By measuring OEE and the underlying losses, you will gain important insights on how to systematically improve your manufacturing processes.

It is the single best metric for identifying losses, benchmarking progress, and improving the productivity of manufacturing equipment since it takes into account the asset availability, its performance, the quality of the products produced and the rejected or wasted material.

OEE = Availability x Performance x Quality

Availability = (Run Time) / (Planned Production Time)

Performance = (Ideal Cycle Time x Total Production Counters) / Run Time

Quality = (Total Actual Production – Rejection) / Total Actual Production

EXAMPLE:

Plastic Manufacturing unit with injection molding machines.?

Quantity = 1000 units

Active Cavities = 2

Ideal Cycle Time = 20 Sec

• Assuming 1st-hour Production:?

Uptime = 30 min; Total Down Time (includes stop time) = 30 min; Stop Time = 15 min

Total Planned Production Time (min) or Planned Time = (1000/2) x 20 x 103? milliseconds

= 500 x 20 x 1000 milliseconds

= 166.66 minutes

~ 167 minutes

Planned Production (Per Seconds) = 2/20 (product/ sec)

= 0.1 (product/ sec)

• Planned Production (running) = 0.1 (product/ sec) x Available Time (Sec)
• Planned Production (1st Hour) = 0.1 (product/ sec) x 3600 (sec)
• Run Time or Production Time (min) = 60 – 30 = 30 min

Calculation of Actual Production using Ideal Cycle Time (sec), Uptime (sec) & Active Cavities:?

• Uptime (sec) = 30 x 60 = 1800 (sec)
• Total Shots in Uptime = 1800/20 = 90
• Total Production (in Run Time) = 180 units (let's assume the Rejection Quantity is 10 units).