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<\/p>\nA concept hardly taken into account in much of the hot-dip galvanized industry is the (apparently obvious) absence of normality of the process.<\/p>\n
Please look at the image below: it corresponds to an analysis of the observed growth of the galvanizing layer in steelwork of more than 6 mm section, with measurements taken in three shifts in a galvanizing plant with standardized processes.<\/p>\n
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For the time being, don’t worry about the graphs and stick with the observed growth model for the averaged values (\u00b5) and the time values per shift (\u00b51, \u00b52, \u00b53).<\/p>\n
If the process were sufficiently standardized, analogous growth patterns between shifts and consistent with the average (top left) could be expected. But it was not like that. In the first shift, a \u00b51 thickness model was observed whose growth rate was 20,7 microns per minute. Things were different on the second shift: before introducing the material into the molten zinc, the minimum thickness was already 112 microns and growth occurred at a rate of 2,9 microns per minute. In the third shift, the values \u200b\u200bwere 92,6 microns for the minimum thickness and a growth rate of 6,2 microns per minute. However, what the plant detected in its product inspections was that this type of material started with a minimum thickness of 90 microns and a growth rate of 6,7 microns per minute. These were the average values \u200b\u200bbetween shifts.<\/p>\n
Of course, the solution was to apply Six Sigma to control the process (reduce variability) and decrease thickness.<\/p>\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
A concept hardly taken into account in much of the hot-dip galvanized industry is the (apparently obvious) absence of normality of the process. Please look at the image below: it corresponds to an analysis of the observed growth of the galvanizing layer in steelwork of more than 6 mm section, with measurements taken in three…<\/p>\n