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Excel Value Stream Map

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  Value Stream Maps graphically represent process flow as it is actually performed. VSM is typically built following a visit to Gemba (where things are really happening)  to depict what is really going on (rather than the theoretical process described in standards and procedures). This approach and VSM concepts are excellently described in " Learning to See " by Mike Rother To follow the value stream you can follow a product along the manufacturing line or a customer order along the administrative value stream like in   " staple yourself to an order " We will analyze the alternative to "Post-Its on the wall" using Microsoft Excel.   Horizontal Vs Vertical Flow Value Stream Maps are typically designed to flow horizontally left to right. When a value stream is complex it becomes difficult to view the whole picture: it may require several pages and this makes it difficult to follow. Making the VSM vertically allows us to visualize a complex value stream in a ...
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Test/ Repair Loop: Potential Value Stream Bottleneck

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  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 ...
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Water Engine Fallacy

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  Some Historical Claims  Multiple "inventors" worldwide have claimed the invenction of engines which run on water alone. 1970 patent Even nowadays some companys claim they can do it . These are some of the claims: With the water engine you don't need batteries. You don't need to carry hydrogen cells. All you need is water. Vested interests of large fosil fuel multinationals are making sure water engine doesn't succeed. An engine that runs just on water Obtain Hydrogen from Water Using electrolysis you can break the water molecule H₂O into hydrogen and oxygen.  Obviously, apart from water you also need an electrical current which has to be supplied by a batttery.  Electrolysis Energy Requirements To obtain 1 kilogram of hydrogen from water through electrolysis, it typically requires around 50 to 55 kilowatt-hours (kWh) of electric energy. Here's a breakdown of the calculation: Energy Required for Electrolysis : The electrolysis of water to produce hydrogen in...
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Random Variation Vs Trends

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Understanding variation is key to interpret the value stream behavior.  Not all variation is the same. Variation These are some factors which may add variation to the process of cooking a turkey.  Every process has variation. Some causes of variation may be identified and acted upon. We can use two metrics for variation which complement each other: Manual Dice Throwing This simple exercise can help to experience process variation and understand the difference between a process change and inherent process variation. This understanding is key on management decisions to avoid both overreaction and lack of reaction. To run the exercise with actual dice print the form: Exercise: You will need a printed form and 4 dice for each team Throw 4 dice and add the outcomes Record the result in the Run Chart Repeat 50 times Join the dots in the Run Chart with a line Build the Histogram by counting the total number of dots on each group of 3 values Run this Exercise with a Simulator Downloa...
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