Plug Valve Inserts

Metallurgy: Ductile iron gets its ductility from the addition of magnesium in the ladle called inoculation. Once magnesium is added, graphite inherent in the iron converts from flakes to spherical nodules imparting superior impact, fatigue, and ductility to the metal. However, this inoculation only lasts 14 minutes until the graphite converts back to flakes, so inoculated metal must be poured and frozen within that 14-minute window to maintain its superior properties. Understanding this, LeanWerks sought out a foundry with capabilities to create a near net casting with in-mold inoculation, which provides a much more uniform grain structure than that of continuous cast ductile iron. Each casting is consistent throughout the lot whereas a continuous cast bar has varying grain structure from the beginning of the bar to the end of the bar. A foundry was identified and a relationship forged that not only produced a near net casting with superior properties to bar stock, but also embraced small lots and frequent deliveries to combat the need to stockpile inventory. Raw material costs per part decreased by 66% (a huge impact since raw material accounted for nearly 50% of the finished part cost) and machining became more efficient as well due to reduced material removal and more consistent metal properties that allowed predictable cutting parameters and tool changes.