hilfsscheibe for wire drawing, extrusion dies for metal, in particular hard malleable metal, e.g. steel, and method for wire drawing, extrusion dies for metal, using the hilfsscheibe

摘要

1365906 Extruding BAYER AG 19 Aug 1971 [22 Aug 1970] 38960/71 Heading B3P An auxiliary block 6, 7 for use in the hot extrusion of metals is composed of a porous plastics-based solid material containing by weight 40% to 400% of the plastics weight of a liquid which evaporates at the extrusion temperature to effect cooling of parts of the extrusion press. The liquid may be water. The plastics material is obtained by polymerization or polyaddition and may contain emulsifiers, hardeners, catalysts and plasticizers. A water-in-oil emulsion may be used containing polymerizable substances such as oleflnically unsaturated homo- and copolymerizable compounds, polyesters or polyethers, of which many examples are given. The liquid phase of the emulsion may contain lubricants such as borates, phosphates, fluorides, chlorides or water glass and the oilphase may contain silver graphite, mica, metal sulphides or silicates. In operation the auxiliary block may be used between the ram and the metal block 8 to be extruded and/or between the block and the die 5. During extrusion the auxiliary block or blocks give off vapour which escapes and cools the parts of the extrusion press such as the ram 2, the die 5 and the container 1. The auxiliary block is used in the extrusion of steel at temperatures of 1120‹ to 1180‹ C. The container, die and ram are preheated to about 350‹ C. and a cooling jacket (not shown) is provided around the container. The press may be used for tube extrusion, Fig. 3 (not shown), using an internally cooled mandrel (11).