Method, apparatus and feeder sleeves for the production of casting moulds

Abstract

A method, apparatus and feeder sleeves are described for producing casting moulds having feeder sleeves incorporated therein in instances when the mould pattern plate or the cope mould are not accessible. Two part feeder patterns having a lower part and an upper part and feeder sleeves whose lateral surface tapers from the bottom and to the top end of the sleeve are used. For moulds having a side feeder the lower part of the pattern produces a depressed seating surface for the feeder sleeve in the drag mould and the upper part which has substantially the same taper as the taper of the feeder sleeve and dimensions greater than the corresponding dimensions of the lateral surface of the feeder sleeve produces a cavity in the cope mould. The cope and drag moulds are closed in such a manner that the central vertical axis of the cavity in the cope mould is in line with the central vertical axis of the feeder sleeve, and there is a gap between the wall of the cavity and the outer lateral surface of the sleeve. When metal is cast into the mould the sleeve floats up and sits firmly and is sealed against the wall of the cavity. For moulds having a top feeder the lower part of the pattern produces a depressed seating surface for a core whose upper surface has means for locating and centering the feeder sleeve.