METHOD FOR EXTRACTING WINDING FROM STATOR SLOTS IN ELECTRICAL MACHINE REPAIRS Russian patent published in 2001 - IPC

FIELD: electrical engineering; repairing electrical machines, mainly those with thermosetting insulation. SUBSTANCE: motor stator to be repaired is placed in autoclave, evacuated at residual pressure of 0.1-5.3 kPa and vacuum build-up time of 0.1-1.5 s. Then stator is treated with destructive aqueous solution saturated with carbon dioxide for disintegrating thermosetting binder of insulation at solution temperature of 80-150 C and stator exposure time under these conditions of 5-20 min followed by raising pressure to atmospheric value and conducting three to five similar cycles in which processes of stator evacuation and pressure increase to atmospheric value are alternating. Destructive aqueous solution containing destruction products is discharged to storage tank wherein it is separated from destruction products and cooled down to make it ready for multiple reuse. Stator is cooled down in autoclave, removed form the latter, winding is extracted from its core slots by mechanical disassembly. EFFECT: reduced repair time (by three to five times) due to augmented treatment by destructive solution without impairing performance characteristics of machine. 1 dwg