Producing hollow metal moulds

摘要

The method concerns production of hollow metal moulds or their parts and inserts which determine the mould contour. It is characterised by the following facts: a) the geometrical data for the mould or its parts and inserts is determined by the geometry and material of the castings to be produced by means of the mould, and cover division of the mould or its parts and inserts, the shrinkage of the casting material, and machining allowances; b) intermediate moulds as three-dimensional negatives of the required actual mould are produced; c) these intermediate moulds are made by sintering powder, granular or granulated materials, and are subsequently hardened; d) they are used to cast the required mould with a contour provided with a machining allowance; e) the mould casting thus produced is machined its final dimensions and surface quality