| 摘要 |
1,269,690. Making casting moulds; drawing. KABELUND METALLWERKE GUTEHOFFNUNGSHUTTE A.G. 13 Nov., 1969 [19 Nov., 1968], No. 55624/69. Heading B3A, B3F and B3P. A longitudinally curved mould, for example a copper arc type mould for a continuous casting machine, is made by pressing a longitudinally curved mandrel having external dimensions equal to the internal dimensions of the mould, preferably a chromium plated mandrel, into a longitudinally curved metal tube, cold forming the tube so that it conforms in shape to the mandrel and removing the mandrel. A mandrel 2 inserted in a tube 1 is pressed through a ring 3 to make the tube conform to the shape of the mandrel. The hardness of the tube is increased from 30-35 kp./mm.<SP>2</SP> to approximately 90 kp./mm<SP>2</SP>. during the cold forming step. The mould formed may be of rectangular, square or polygonal section or it may be conical. |
