Automating factory performance diagnostics using overall throughput effectiveness (OTE) metric

The overall equipment effectiveness (OEE) metric is a powerful tool that can be used to measure performance and also perform diagnostics at the equipment level. Although important, gains made in OEE are insufficient; because the ultimate objective is a highly efficient integrated system, not brilliant individual equipment. Factory level performance monitoring and diagnostics can be facilitated by classifying the entire manufacturing system layout into unique subsystems including series, parallel, assembly, and expansion. The overall throughput effectiveness (OTE) metric is then derived for each of these subsystems. Factory level metric can be computed by synthesizing the subsystem level metrics, capturing their interconnectivity information. The objective of this paper is to present the algorithms developed to automate the factory-level performance monitoring and diagnostics process using OTE. The algorithms are implemented into a software tool called SIMPRO. SIMPRO allows factory professionals to efficiently measure performance and conduct factory level diagnostics (i.e., identify bottlenecks/hidden capacity). A glass manufacturing case study is used to illustrate automated performance diagnostics and the benefits obtained by using the approach.