Statistical tools applied for the reduction of the defect rate of coffee degassing valves

(in lingua inglese)

A problem of high defect rate in the production of coffee valves was tackled, using first the basic tools of quality design and performing a dimensional analysis of the involved parts. Subsequently, a statistical analysis of the data, led to the determination of their distributions. Afterwards, an easy approach was proposed, to indicate the most suitable strategy to improve production quality, predicting the achievable defect rate. A specific requirement addressed to the suppliers led to more conformal dimensions of the covers, with the final result of a significant decrease of the defect rate to acceptable values.