"Fewer Checks - Higher Quality" - The Canmaker - March 2007
"It?s been tough for the canning and seaming industries, with thinner material gauges, end diameter reduction, increasing costs and higher productionrates."
Despite this, few companies use the best quality control (QC) methods.
In production QC, processes are typically normal or random. Random processes produce defects which cannot be foreseen, and require every can to be tested. Normal processes, meanwhile, are deterministic: slowly changing away from the preset nominal and gradually going out of specification.
Seaming is a normal process. Production begins with good products being manufactured. Slowly, one or more measurement values drift out of specification. Once a problem is identified using regular statistical sampling, the line is stopped and the problem corrected."
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