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  When we need to process different products in the same line we want to work out the best job sequence to minimize lead time and maximize capacity utilization. We also need to work out the minimum lot size to meet the demand and minimize lead time. Before we can commit the delivery date of a new job to the customer we need to know the  state of the jobs already being processed For non repetitive processes you can use project management scheduling The ideal of "Lean Production" is lot size of 1 but this is not always possible when change-over time is significant. This change-over involves loading different components and changing jigs or molds. When change over or setup time is significantly higher than process time we are forced to work with larger lot sizes. One way to minimize lot size is to minimize setup time. The SMED (Single Minute Exchange of Dies) methodology has been very successful to reduce setup times from hours to minutes.  Scheduling Constraints In a sequenti

  Test and Repair are Non-Value-Add operations: defective products should not be produced on the first place. Unfortunately the state of the art in many processes is not there so tests and controls need to be part of the value stream.  Ideally as the value stream becomes more robust some of these controls can be removed. On the mean time we need a test and repair plan (if repair is possible). A Test/ Repair loop can become a bottleneck for the whole Value Stream when Test First Pass Yield is lower than planned. A drop in FPY is normally caused by problems upstream in the Value Stream as seen in   Defect generation and detection Test/ Repair loops are often absent in Value Stream Maps in spite of the potential to become the bottleneck for the total process. Download this Excel example file   TestRepair.xlsm   to your PC from OneDrive folder   Polyhedrika You must close all open Excel files before you open this one and you should enable Macros . To simulate 1 hour operation just press  F