GB1407232A - Heating of billets - Google Patents

Abstract

1407232 Shearing; forging; rolling INDUCTOTHERM EUROPE Ltd 17 April 1973 [27 Jan 1972] 3901/72 Headings B2W B3H and B3M [Also in Division H5] A metal billet is heated prior to cropping, forging, rolling &c. by means of a pair of electrodes (22) (Fig. 2, not shown) gripping the billet at one end and mounted on columns 10, and a pair of electrodes (32) (Fig. 3, not shown) mounted on a carriage 38 movable along a top beam 14 to enable the electrodes (32) to grip the other end of the billet. Associated with the fixed electrodes (22) is a fixed pair of bus-bar assembles 50. A second pair of bus-bar assemblies, 52, is connected to respective electrodes (32) and each assembly includes a knuckle joint 58, 60 to accommodate movement of the carriage 38. A further carriage or carriages such as carriage 62 may support sections 54, 56 of the assemblies 52. An electrically-conductive joint between the sections of the bus-bar assemblies comprises a headed pin passing through aligned apertures in adjacent sections and Bellville washers located one on each side of the sections and stressed by a nut engaging a threaded portion of one pin. In operation, a billet is moved to the left, Fig. 1 up to a ganging stop by V-section rollers 16a of a conveyer 16 and raised to electrode level by fluid-operated jacks (18) Fig. 2. The electrodes (32) are moved, if the length of the billet requires it, by a manually-controlled fluidactuated ram 44. Electrodes (22) and (32) are then advanced to grip the billet by fluidactuated piston and cylinder units and are supplied with electrical power. The period of heating may be controlled by a pre-set timer or a thermally-responsive switch. The preferred billet temperature for cropping is 500‹-600‹ C. For subsequent forging of the cropped blanks, further similar heating means may be provided or the billet may be raised to 1250‹ C. in the pre-cropping heater.