What is Overall Equipment/Machine Efficiency (OEE):
OEE is the framework for measuring the efficiency and effectiveness of a process, by breaking it down into three constituent components (Availability, Performance and Quality product rate). It helps to measure a problem so that easily can fix it and provides a standardized method of benchmarking progress. OEE identifies the percentage of planned production time that is truly productive.
Overall Machine Efficiency

Overall machine or equipment efficiency is the how to performs machine versus spec. In practically,

OEE= Availability X Performance Rate X Quality Product Rate

Where,

Loading time – Down time
Availability = ………………………………………. X 100
Loading time

Standard cycle time x Processing quantity
Performance = …………………………………………………. x 100
Operating time

Processing quantity – Defective quantity
Quality product rate = ……………………………………………………………. X 100
Processing quantity

Let,
Working hours per day: 10 hours x 60 min = 600 min
Shut down (SD): 35 min
Loading time: (600-35) = 565 min
Equipment stoppage/ down time: (30+20+25) = 75
(a) Failure : 30 min
(b) Set up : 20 min
(c) Adjustment : 25 min
Operating time : (565 – 75) = 490 min
Standard Cycle time : 0.35 min/ pieces
Processing quantity : 550 pieces/ day
Defective : 30 pieces.
Now,

Loading time – Down time
Availability = ……………………………………………. X 100
Loading time

565 – 75
= ………………….. x 100
565

= 86.72%

Standard cycle time x Processing quantity
Performance = ………………………………………………….. x 100
Operating time

0.35 x 550
= ……………………. X 100
490

= 40.35%

Processing quantity – Defective quantity
Quality product rate = ……………………………………………………………………. X 100
Processing quantity

550 – 30
= …………….. x 100
550

= 94.54%

So, OEE = Availability X Performance Rate X Quality Product Rate

= 0.8672 X 0.4035 X 0.9454

= 33.08%

Low Machine efficiency rate due to man:
Management Losses;
Motion Losses;
Adjustment Losses;
Losses resulting from lack of automation and
Monitoring Losses.