The document describes a successful application of Akselos’ engineering simulation software at a North American operation. Based on outdated temperature ramps and Minimum Pressurization Temperature (MPT) curves, the operator’s existing practices were replaced with a digital twin model of the reactor, significantly reducing reactor downtime. Akselos’ solution safely trimmed start-up and shutdown times by over 25%, improving plant uptime. The provided operations dashboard enabled optimizing thermal ramps in real-time, facilitating risk-based inspections and better scheduling maintenance. The solution ultimately maximized the reactor’s life and boosted operational efficiency by allowing more informed decisions.