Ajuste preventivo versus ajuste corretivo no controle on-line de processo do número de não-conformidades num item inspecionado

摘要

In production lines, the entire process is bound to unexpected happenings whichmay cost losing the production quality. Thus, it means losses to the manufacturer.Identify such causes and remove them is the task of the processing management. Theon-line control system consists of periodic inspection of every month produced item.Once any of those items is quali ed as not t, it is admitted that a change in thefraction of the items occurred, and then the process is stopped for adjustments. Thiswork is an extension of Quinino & Ho (2010) and has as objective main to make themonitoramento in a process through the control on-line of quality for the number ofnon-conformities about the inspected item. The strategy of decision to verify if theprocess is under control, is directly associated to the limits of the graphic control ofnon-conformities of the process. A policy of preventive adjustments is incorporated inorder to enlarge the conforming fraction of the process. With the help of the R software,a sensibility analysis of the proposed model is done showing in which situations it ismost interesting to execute the preventive adjustment