Blind feeder sleeves

摘要

A blind feeder sleeve for use in the casting of metals comprises a sleeve body and a cover having a Williams core, and optionally an opening for ventilation, the Williams core being formed integrally with the feeder sleeve and comprising a rib extending across the inner surface of the cover and projecting downwardly from that surface in a wedge like shape. Preferably the rib is formed integrally with the inner surface of the cover at each end of the rib, and when the feeder sleeve is circular in cross-section the rib preferably extends across a diameter of the sleeve.