When Logic Takes Over Intuition

Author:  Erik Waelchli | Owner of IBD Connection, Inc. and Consultant for Electronics Inc.
Source:  The Shot Peener magazine, Vol 37, Issue 4, Fall 2023
Doc ID:  2023034
Year of Publication:  2023
Abstract:  
HERE IT GOES: Electronics, Inc. has a significant variety of media types in inventory which are used to test valves, sensors and Almen strips. Recently we reviewed the inventory list, and for some of the containers we had actual weight-in-stock. We looked for a way to get an approximate weight simply by measuring the fill-level of the container. Intuition struck and the need for a bulk-density table based on media type was on the table. Intuition said, smaller media equals higher bulk-density! No problem we thought—let’s call the experts at Ervin Industries! Michael Konecny and Rick Payne with Ervin promptly fed us the answers: 7.14 – 7.69 g/ccm (~7.5 g/ cm3) for the shot-material density and 286.82 lb/cu-ft for the shot-media bulk-density—the handwritten note said: “currently 280 shot”. A bit frustrated, having now only one data point, the 280 shot, I decided to make a simple test, weighing some different sizes of cast-steel shot in EI’s inventory. The results baffled me as the given volume for all shots had approximately the same weight! How could this be? Smaller media has smaller voids around itself, while larger shot has bigger voids. I was convinced, therefore, the larger shot would have a smaller bulk density over the smaller shot. So, I consulted “Uncle Google”! (See QR codes at the end of the article.)