Polyhedrika

System constraints are key when it comes to optimizing our value stream. The process bottleneck limits the overall throughput and it determines such things as manufacturing lot sizes. Learning by doing is an effective way to understand how a value stream works. With this simple manufacturing line simulation you can experience the effects of alternative solutions in order to maximize profit.  When resources are shared by several products there is a setup time when changing product and you have to decide what is the optimal production lot size to optimize the process. Download this Excel file TOCeng5.xlsm from OneDrive folder Polyhedrika Close other Excel files before you open this one and enable Macros. Process Objective Run the simulator to obtain the maximum profit after one simulated week. You have an initial capital of 1000 € which you can use to buy materials to feed the blue, green and brown machines. Fixed expenses amount to 2000 €/ week and they will be subtracted from th...

  The Theory of Constraints is a process improvement methodology that emphasizes the importance of identifying the " system constraint " or bottleneck. By leveraging this constraint, organizations can achieve their financial goals while delivering on-time-in-full to customers, avoiding stock-outs in the supply chain, reducing lead time, etc. Manufacturing Process Example With this simple value stream above, to produce products A and B, we want to illustrate the way to maximize profit taking into account the system constraints . Each product is made by assembling two sub assemblies, one of them common to both products. The process consists of three sequential operations for which there are special purpose workstations with a corresponding operator each trained for the specific job: Manufacturing Test Assembly We want to know how many products A and how many B we should produce to maximize profit. System Constraints Product Margin We want to maximize overall profit so we calcu...

The quality level seen by the customer of our value stream is one of the most critical process metrics. This quality level is the result of all the defects generated by the different process steps as well as those coming from the parts suppliers.  Ideally defects should not be produced in the first place. Unfortunately the state of the art, in many technologies, is still not there. Therefore, on the mean time, we need process tests and controls to catch and correct defects as soon as they are produced. In our Value Stream Map we focus on process flow but this flow is very much affected by quality.  It is important to find out where in the process each type of defect is generated and where in the process it will be detected to make sure it doesn’t find its way to the customer. Control Plan The Control plan defines all the controls, visual, test, etc., installed along the value stream in order to catch the defects as soon as they are produced in order to correct them and give im...