One-piece mandrel, which can be broken down by a chemical route, and process and device for manufacturing such a mandrel

摘要

The one-piece mandrel M1 according to the invention is manufactured by compressed-air injection of a material M, hardening at ambient temperature, into a dismountable mould 12. The material M is an agglomerate of sand and of a binder consisting of a polymerised phenolformaldehyde resin with a hardener such as a diisocyanate, in the presence of a catalyst such as an amine, preferably liquid. After producing a workpiece on the mandrel, the latter is disintegrated by means of an organic solvent. <IMAGE>