METHOD OF MAKING MANDREL FOR MOULDING PRECISION COMPOSITE ENVELOPES Russian patent published in 2001 - IPC

FIELD: production of precision articles from polymeric composite materials. SUBSTANCE: method of mandrel making includes making of envelope mould, application of antiadhesive coating to inner surface of envelope mould mixture solution into envelope mould and its cold hardening. Envelope mould is made by mounting support adjustable screws on base of envelope mould. End face part of each support adjustable screw is made in form of semi-sphere. Each support adjustable screw is installed by aligning upper point of semi-sphere with required form of surface of precision composite envelope to be moulded, then thin-walled envelope coinciding in form of inner surface with form of surface of precision composite envelope to be formed is installed on semi-spheres of support adjustable screws. Thin-walled envelope is secured on semi-spheres of support adjustable screws. Moulding mixture solution is poured into envelope mould layer by layer and after hardening of moulding mixture solution, thin walled envelope is separated from mandrel, thus made. EFFECT: reduced cycle of mandrel making, improved accuracy of working surfaces of mandrels. 2 dwg