Cooling pads for water-cooled stator cores in dynamoelectric machines and methods of fabrication

A water-cooled stator core for a dynamoelectric machine comprising:

• a plurality of stacked, generally annular, stator core laminations;
• and
• a plurality of generally integral annular one-piece cooling pads interspersed between at least certain adjacent laminations in the stack thereof;
• each of said pads including a generally circumferentially extending cooling tube carried by and embedded within said annular pad, each tube having an inlet and an outlet for flowing cooling water therethrough and extending circumferentially substantially about the full annular extent of said pad, said tubes being surrounded by material forming said pads such that all surfaces of the circumferentially extending tubes embedded within said pads are not exposed through annular faces of said pads.

A method of forming a cooling pad for a water-cooled stator core of a dynamoelectric machine comprising the steps of:

• depositing a coating of aluminum on a generally annular stainless steel cooling tube by plasma-spraying the aluminum onto the tube;
• disposing the aluminum-coated tube in a mold for forming a generally annular cooling pad;
• and
• depositing molten aluminum into the mold to produce an aluminum pad casting thereby embedding the aluminum spray-coated tube in all areas of the mold included in the casting with the cast aluminum bonding to the spray-coated aluminum.

A cooling pad for a water-cooled stator core of a dynamoelectric machine comprising:

• an annular pad for disposition between stator core laminations in the dynamoelectric machine;
• at least a pair of generally circumferentially extending cooling tubes disposed in said annular pad at radially spaced, substantially concentric locations relative to one another;
• each of said tubes having an inlet and an outlet and extending circumferentially substantially completely about said pad;
• each tube being formed of stainless steel and having a coating of aluminum deposited by a plasma spray process, said pad being formed of aluminum cast about said aluminum spray-coated tubes forming an integral bond therewith.