Calculation of Overall Equipment Efficiency (OEE)
OEE is widely used in manufacturing and service industries to calculate machine efficiency. It is a metric quantity and easy to calculate. OEE has become an integral part of lean manufacturing principles. In order to improve productivity in every organization, we recommend that OEE be calculated to serve as the basis for development efforts.
Three measurable conditions, quality, availability and performance are calculated from the OEE perspective to calculate the performance of an organization. Any parameter of any manufacturing organization can be selected for development efforts. One of its advantages is that it can be applied to the entire plant, any class or any workplace. In this effort, 100% OEE is considered ideal and is not available, but 85% is targeted by a number of organizations.
OEE = Availability x Performance x Quality
is the actual value of OEE, an example for a production plant where the machine's production capacity is 87%, the power level of the plant is 94% and the component 90 % of good quality. So the OEE of the plant
OEE = 87 x 94 x 90 = 73.6%
Now let's look at how to calculate the above three parameters to calculate the desired value
first we need to look at how long is in operation and ready for manufacturing activities. From this time we deduct the planned maintenance and shutdown time (machine failure, lunch break, teaspoons and standby time). Finally, we get full operating time. From that time, we will subtract other unnecessary delay times to reach the net availability time needed for production. This delay may include unplanned demolition, electrical problem, tool and work time change, unavailability of raw material and lack of appropriate equipment
Performance is the machine's and operator's efficiency. The efficiency of the machine can not occur in many cases compared to the nominal values, such as wear, jams, and the lack of a suitable device. And the effectiveness of the operator may be less because of the less educated person. When both efficiencies are multiplied, the performance of the operator and the machine is obtained
Quality is calculated by calculating the total number of products produced and subtracting rejected and recycled pieces
For example, to calculate the actual value of the OEE, based on sieving. The values are as follows:
Total time = 8 hours / 480 minutes Manufacturing pauses = 1.5 hours / 90 minutes Machine down time = 20 minutes Machine's ideal production speed = 55 pieces Total production = 17665 Rejected total = 430 [19659002] Full Design Time = Total Time – Production Breaks = 480 – 90 = 390 Minutes
Full Operating Time = 390-20 = 370 Minutes
Total Manufactured Items = 17665 to 430 = 17235
= Total Operating Time / Total Design Time = 370/390 = 0.9487 = 94.87%
Power = (Full Production / Full Operating Time) / Machine's ideal production speed = (17665/370) / 55 = 0.8680 = 86 , 8%
Quality = Total Manufactured / Total Production = 17235/17665 = 0.9756% = 97.56%
OEE = Machine Availability x Performance x Quality
= 94.87 x 86.8 x 97.56
= 80.33% [19659002] Thus the machine's overall efficiency is 80.33%
Source by sbobet