Abstract: A heat exchanging roller has an inner and an outer generally cylindrical casing with an annular space defined between them through which the heat exchanging medium passes. Sealing rings are disposed at the ends of the roller and bound the annular space. Sets of clamping mechanisms connect the sealing rings to the casing. Each clamping mechanism consists of two single conical lock washers, a double conical clamping ring and tightening screws which are threaded into associated boreholes in the sealing rings. The sealing rings are designed as centering rings of which the radial circumferential surfaces cooperate with the associated centering surfaces on the inner and outer casing. The circumferential surfaces each include at least one groove for receiving a resilient seal.