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Real Time Value Stream Data Collection

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  Value streams require real time data collection to control them. This is often done automatically by the equipment itself, but in some occasions it must be done manually.  In spite of the high-tech of our shop floors you can still see pencil and paper data collection being used. https://youtu.be/AIq8yi2Ej4s Unfortunately, detecting aspect defects is often difficult to automate even with AOI (Automatic Optical Inspection). When an operator is required to inspect, we need a method to enter the results into the system. Line incidents, change of critical process parameters, etc. also need to be reported the moment they hapen. Pencil & Paper Reporting The method, still widely used in this 21st century, follows these basic steps: The operator hand writes the defect data on a form Forms are collected at the end of the shift A clerk types the forms contents into the system at a later stage The engineer analyses the results and takes corrective actions, well after the data wa...

Response Surface Design Of Experiments with Excel

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Design of Experiments is a useful methodology for process improvement. The purpose is to find a relationship between process variables we can control, and key process outputs, to increase process capability . You can use Excel statistical analysis tools, Solver, Pivot charts, etc. to plan and analyse the results of these experiments. The first approach is to look for a linear relationship, as shown in:   Excel DOE But in some cases this relationship may not be linear, in which case we will try a quadratic model with Response Surface DOE . We will use an example in this Excel file you can download: Download file   ExcelResponseSurface.xlsm   from OneDrive to your PC. In this example we are trying to maximize process yield, acting on the critical factors pH , Temperature and Time . We will run the experiments in the Experiments simulation sheet using coded values.   Code pH Temperature Time -1 2 120 7 1 12 150 15 Factorial Experiments We start by running...