Method of applying outer insulation to a stator bar of an electric machine

A method of applying an outer insulation to a stator bar for an electric machine, the method comprising the steps of:

• extruding the outer insulation to comprise at least one extruded member containing an electrical insulation material, the at least one extruded member having an inner cavity extending a longitudinal length thereof and an opposing pair of edges parallel to the longitudinal length thereof;
• inserting the stator bar into the inner cavity of the outer insulation so that the outer insulation surrounds a perimeter of the stator bar and extends along a longitudinal length thereof;
• and then
• attaching together the opposing pair of edges of the at least one extruded member so that the perimeter of the stator bar is entirely enclosed by the at least one extruded member;
• wherein the at least one extruded member is extruded so that slots are defined in each of the opposing pair of edges so that each slot of a first of the opposing pair of edges opposes a corresponding one of the slots of a second of the opposing pair of edges;
• and the attaching step comprises inserting a member in each pair of the opposing slots to mechanically secure together the opposing pair of edges.