A pole part of a switchgear assembly having a vacuum interrupter chamber is provided. To ensure that heat is dissipated to the exterior for convection, a thermally conductive heat transmission element in the form of a cylindrical casing is provided between the vacuum interrupter chamber, a contact holder and an encapsulation casing. An inner surface of the heat transmission element rests on the vacuum interrupter chamber and the contact holder, and an outer surface of the heat transmission element rests on an inner surface of the encapsulation casing inner surface. The heat transmission element can be produced from a thermally conductive plastic using an injection-molding or molding-compound production process. The heat transmission element can be connected to the pole part through openings. The heat transmission element can be arranged before the encapsulation of with an encapsulation compound, and be cast in the encapsulation casing.