This paper introduces CraneFlow, a novel simulation framework for bridge and gantry cranes. By combining salabim’s discrete-event simulation environment and ruckig for time-optimal trajectory planning with jerk limits, CraneFlow enables detailed, load-dependent motion modelling. The framework is fully open source, allowing for extensive customization and integrations. To assess the need for detailed crane motion modelling, we present a systematic evaluation of six major simulation platforms, analysing their support for axis-specific motion constraints (velocity, acceleration, deceleration, jerk), concurrency patterns, as well as scheduling and collision avoidance logic. In a real-world case study of an automated coil storage yard, we show that higher-fidelity motion representations can significantly alter throughput estimates and thus system design decisions.