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Flow meter drift is a serious problem, the financial losses from which can be huge. Flow meters do not usually get much attention and a drift can go unnoticed for a long time. In this research, a novel method is presented for the early detection of flow meter drift. The method is based on statistical process control (SPC). The method can be used with any type of flow meter (ultrasonic, magnetic etc.) regardless of its manufacturer. Another advantage of the presented method is that it does not require any knowledge of the mathematical models and relations that govern the process. The method is also capable of working with minimal data: only the monthly billing data are needed. Adapting the process can be done inexpensively.
cusum, data analysis, flow meter, flow meter drift, statistical process control
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