The document discusses simulation modeling to improve quality and productivity in steel cord manufacturing. It describes the steel cord manufacturing process, which involves successive bunching operations to construct steel cords from steel filaments. It aims to determine optimal spool lengths to minimize rejected spools containing knots while keeping spool lengths close to current levels. A simulation model was developed in C++ to estimate key performance measures and validate the model against historical data. The simulation found some current operational rules useful and suggested investigating dynamic control policies.