Portable, electrically-powered tube swaging machine - achieves high power to wt. ratio using three=phase motor operating on 42 volts and 300 Hz supply

摘要

An electrically powered tube rolling unit to allow expansion of tube ends is designed to be portable, to have high power to weight ratio, robust construction for long operational life and low voltage for safe operation. A control unit is used to provide conversion of a standard 380V/50Hz three phase supply into a 42V/300Hz supply considered to give optimum performance. The use of a three phase motor operating in a h.f. supply provides good power to weight ratio, while the l.v. provides safe operation. The controller provides measuring and time relays for controlled switching and a combination of current and voltage converters for changing the supply.