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Overall Equipment Effectiveness / Overall Equipment Efficiency OEE measures the utilization of a machine. It is a ratio of the parts produced vs the theoretical capacity. Causes of OEE · Availability. Availability Losses can be due to planned maintenance, unplanned repairs, breakdowns, material shortage, changeovers, lack of transport for finished goods, absence of operator, etc. · Performance. Speed Losses are reduced rate of production due to wear and tear, poor maintenance, idling, lack of training leading to incorrect operation, wrong settings, etc. · Yield. Quality Losses are losses due to defects. These wastages can be in the form of scrap, rework, and start-up losses. Example. · Theoretical OEE – 100 parts per hour · Availability Losses – 5 parts per hour · Speed Losses – 10 parts per hour · Quality Losses – 15 parts per hour · Good parts produced – 70 · OEE – 70% TAKT Time Takt is a musical term. In German it means beat. It is the rhythm/rate at which production needs to be paced in order to meet customer demand. It is measured in Time/Unit. It helps in planning the resources such as employees, machines, raw material, transport, storage, etc with respect to the required production. Customers, transporters, employees, etc., can be given an accurate estimate of when to expect the finished goods. The Takt time changes as the business grow, hence necessary action such as increasing capacity will need to be taken to stay ahead of demand. Takt Time = Total Available Production Time/Customer Demand Example Total Available Production Time/day = 480 Minutes Cycle Time Cycle Time is the time spent on a specific task for one unit. Time/Unit Example 1. Unbalanced Line Cycle Time. · Cycle Time Task A = 30 sec/part, · Cycle Time Task B = 60 sec/par - Bottleneck, · Cycle Time Task C = 15 sec/part, · Cycle Time Task D 15 sec/part · Throughput without OEE = 60 parts/hour · Target Cycle Time = 60 Sec x 0.8 OEE = 48 Sec · Throughput with OEE (80%) = 3600/48 = 75 Parts Per Hour Example 2. Balanced Line Cycle Time. · Cycle Time Task A = 30 sec/part, · Cycle Time Task B1 = 30 sec/part, · Cycle Time Task B2 = 30 sec/part, · Cycle Time Task CD = 30 sec/part · Throughput without OEE= 120 parts/hour · Target Cycle Time = 30 Sec x 0.8 OEE = 24 Sec · Throughput with OEE (80%) = 3600/24 = 150 Parts Per Hour The target cycle time for a process is Takt Time multiplied by the OEE If the Target Cycle Time for a process is optimized without taking into consideration the reduced production due to OEE losses, it is likely that the customer demand is not going to be met. For the customer demand to be met taking into consideration OEE losses the · Average Output >= Average Customer Demand or · Target Cycle Time <= Takt Time x OEE This is illustrated in the examples above References https://www.benchmarksixsigma.com/forum/topic/36096-overall-equipment-effectiveness-oee/#comment-50835 https://www.allaboutlean.com/oee-definition/ https://www.allaboutlean.com/line-balancing-3/