H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
H02K—DYNAMO-ELECTRIC MACHINES
H02K5/00—Casings; Enclosures; Supports
H02K5/04—Casings or enclosures characterised by the shape, form or construction thereof
H02K5/12—Casings or enclosures characterised by the shape, form or construction thereof specially adapted for operating in liquid or gas
H02K5/128—Casings or enclosures characterised by the shape, form or construction thereof specially adapted for operating in liquid or gas using air-gap sleeves or air-gap discs