On monitoring mixture weibull processes using mixture quantity charts

The study proposes a cumulative quantity control chart, based on the mixture of two components Weibull model, namely MWQ-chart. The design structure of the proposed chart is developed by using the cumulative quantity examined between non-conformities (Q) as the charting statistic. The performance of the proposed MWQ-chart is evaluated in terms of some popular measures like average run length and average length of inspection. The cumulative quantity control chart is discussed as a special case. An extension of the proposal is also suggested in the form of MWQr-chart based on the cumulative quantity between non-conformities until r nonconformities happened in one or both components of the mixture model. The implementation of the proposed chart is also shown on a dataset for practical demonstration.