Plate
Foundry plates are of two kinds principally, being for the purpose of carrying or covering moulds. Those used for carrying are usually plain open-sand plates, with handles or lugs made in a form suitable for the lifting tackle used; whilst the covering plates have dabbers or prickers cast on them for sustaining the loam or sand with which they are covered on the mould or face side. See PRICKERS; LOAM-MOULDING; OPEN-SAND MOULDING. Plate Brass is cast brass for rolling into sheets, and is composed of copper 16, zinc 3. See BRASS.
Plate-moulding is simply dividing the pattern to be moulded exactly at the joint or parting, and placing the halves opposite to each other on an iron plate or a board, which is provided with pin-holes exactly corresponding to the interchangeable flasks to be used. Cope and nowel may then be rammed respectively, cope lifted off, plate taken away, and the cope again pinned to place. If distinct plates are made for each side the operations are facilitated somewhat, as all the nowels can be completed at once and the copes follow in succession: the advantage in the latter method is, that the plate is withdrawn from the mould in both cases, while in the former the cope is lifted off the plate-a bad feature when the patterns are not comparatively plain. When more than one pattern are thus treated, and all run from one common gate, it is customary to call it a card of patterns. See MATCH-PLATE. Platen, in moulding-machines, is the upper diaphragm or plate, against which the flask with its containing sand and pattern is forced by pressure from below. See MOULDING-MACHINES.