GB853210A - Improvements in or relating to extrusion - Google Patents

Abstract

853,210. Extruding. BRITISH IRON & STEEL RESEARCH ASSOCIATION. May 5, 1959 [Feb. 5, 1958], No. 3754/58. Class 83 (4). In the extrusion of a metal billet through a die located at the end of the billet container, a dummy billet, consisting of two transverse endsheets acting as sealing members to prevent backward extrusion and an intermediate body portion capable of transmitting the extrusion pressure, is interposed between the metal billet and the extrusion ram to enable the whole of the metal billet to be extruded. The body portion may be of powdered material such as graphite, mica, glass, asbestos, bentonite, lime or alumina or mixtures thereof, and end-sheets of mica or asbestos. Powdered glass or glass fibre are used for lubricating the dummy billet. The body portion may be enclosed initially in a split steel sleeve held by a clamp which is released as the dummy is inserted into the container. Alternatively the body portion may comprise layers of solid materials. The dummy billet is preferably preheated prior to being placed into the container; when a steel billet is extruded the dummy billet is heated to at least 300‹ C., preferably 800‹ C. The extrusion die has a sloping entry leading to a parallel throat. The ram has a dummy block attached thereto. When used in the extrusion of tubes the dummy billet is hollow to accommodate the mandrel. Specific examples are given. 853,315. Consolidating scrap cans. ROBERTSHAW Ltd., M. F. Jan. 30, 1958 [Jan. 30, 1957], No. 3219/57. Class 83 (4). Apparatus for crushing hollow metal articles such as cans 2 comprises a pair of relatively movable crushing members 5, 6 movable towards and away from each other and guide means 1 adapted to guide the articles one at a time between the crushing members. The cans are fed one at a time from a hopper, which may be vibrated, down a shoot 1 and through a slot 4 in a casing 3 where they lie between a fixed abutment 5 and a ram 6 connected by a rod 15 to an hydraulic piston 16, Fig. 3 (not shown), supplied through valves with pressure liquid by an electrically-driven pump. The ram 6 crushes the can and upon withdrawal of the ram the can falls through an aperture 12 into a delivery shoot 11. Alternatively the can may be crushed between a pair of movable rams or the crushing members may be a pair of pivoted pincer clamps. The crushing apparatus may be portable. 853,327. Welding by fusion. BRITISH OXYGEN GASES Ltd. May 5, 1959 [May 14, 1958], No. 155l8/58. Class 83 (4). A fusion spot-weld is formed to join overlapped metal members 1, 2, Fig. 1, by locating a preformed metal insert 6 in an aperture extending through one of the members 1 to the common interface and fusing the insert 6 and the adjacent parts of the members 1, 2 by use of an arc welding torch having a non-consumable electrode, e.g. a tungsten electrode. The members 1, 2 are held by a clamp 4 against a backing-plate 3. The arc is shielded by a gas such as argon. The insert 6 is of the same size as or larger than the aperture and may be coated with a deoxidizer, an arc stabilizer or a flux. The insert 6 is of the same or different metal as one or both of the members 1, 2 and may include or consist of sintered metal. A killed steel insert is used in welding unkilled mild steel members. In a modification for overhead welding, the insert 46, Fig. 4, is so shaped that it is retained in the correspondinglyshaped aperture 45.