APPLICATION OF INTEGRATED SEMI-HOT STAMPING TECHNOLOGY FOR THE PRODUCTION OF HUB AND FLANGE TYPE PARTS

The main part of the cost of machine-building products is the cost of the metal used to manufacture the part. In order to reduce the amount of metal waste and improve the quality of stamped forgings, new technologies have been developed for the production of standard machine-building parts such as "hub" and "flange" based on the integrated technology of semi-hot stamping from a ball blank. According to the factory technology, the parts in question are produced by hot-dip stamping: metal is divided into cylindrical blanks for subsequent stamping by cutting on press shears, the weight spread of such blanks is 10 ‒ 12 %; metal is heated for stamping to a temperature of 1150 – 1200 °C, when heated to such temperatures, scale forms on the surface of the workpiece; stamping in open dies with pre-laying of a cylindrical billet and clipping of a chip. According to the developed technologies, the initial blank is an accurate ball blank obtained by separation in cross-screw rolling mills, the mass spread of which does not exceed 8 %. The heating temperature for stamping is reduced and is in the range of 850 ‒ 900 °C, when heated to temperatures of semi-hot stamping, scale does not form on the surface of the blank; stamping is carried out in one the transition is in a closed stamp. Comparative schemes of manufacturing parts according to factory and developed technologies are presented. The conducted studies have shown that the use of integrated technology allows to obtain accurate forgings by weight with minimal allowances for subsequent machining in fewer operations and save up to 25 % of the metal from the initial mass of the workpiece.