The international standard ratio to measure Production Efficiency is called OEE (Overall Equipment Effectiveness).

NOTE: With regard to Work Management, for information on how the availability and speed ratios are calculated in a way more appropriate for processes which are persons, please view 'operation time' in processes configuration.

OEE CALCULATION:

The advantage of the OEE, compared to other ratios, is that it measures, in one ratio, all fundamental parameters regarding productive losses: Availability, Speed and Quality.

These three ratios compose the OEE and, by analyzing them, it is possible to know what losses, until 100%, are caused by:

    • AVAILABILITY: the process stops and it is not working due to failures or idle periods or there were no results during the time that could have been used for production.
    • SPEED: results are not obtained in the expected time.
    • QUALITY: results are not good enough, so they are discarded or reworked.

AVAILABILITY CALCULATION:

Availability = B / A

Where:

    • A. Available time = total time that the process could have been producing = [natural time] - [not scheduled time to produce] (such as holidays, lunch, programmed maintenance tasks, weekends...).
    • B. Running time = time the process has being producing = [available time] - [failures and idle times]

SPEED CALCULATION:

Speed = D/ C

Where:

    • C. Theoretical production = number of products that could have been produced = [running time] * [nominal production speed].
    • D. Real production = number of products produced = [theoretical production] - [microstops and speed loss]

QUALITY CALCULATION:

Quality = F / E

Where:

    • E. Real production = total number of results produced.
    • F. Good production = total number of good results produced.