An insert assembly is provided for a rotary machine wherein the rotary machine comprises a rotor and a casing. The rotor comprises a generally longitudinally-extending axis. The casing is generally coaxially aligned with the axis. The casing circumferentially surrounds and is radially spaced apart from the rotor. The insert assembly comprises a channel circumferentially disposed on the rotor and an insert circumferentially disposed in such channel such that the insert assembly is configured to thermally isolate frictional heat from the rotor to the insert.