nozzle 214 and flows through the nozzle 214 toward the calender roll 210 as in the first and second embodiments each nozzle 214 contains internal heating elements 218 which may be used to heat the air as it flows through the nozzle 214 the heating elements 218 comprise lengths of resistive wire 256 strung between conductive posts 258 which are disposed at opposite ends of the nozzle 214 each nozzle 214 is 10 inches long however the nozzles 214 may be longer or shorter depending upon the desired degree of nip control these nozzles 214 have concave ends 260 which conform to the surface of the calender roll 210 the concave nozzles 214 in this embodiment serve functions similar to the shroud 132 see fig3 in the second embodiment of the present invention the concave ends 260 of the nozzle 214 constrain the air emitted from the nozzle orifice 262 so that it remains in contact with the calender roll 210 until the air emerges at the edge of the nozzle 214 since the hot or cold air emitted from the orifice 262 remains in contact with the calender roll 210 for a longer period of time more heat is transferred between the roll 210 and the air additionally the concave nozzles 214 prevent cold ambient air from being entrained by the air jets as previously mentioned this would reduce the effective temperature of the jets the plenum 212 is pivotally mounted on pivots 264 266 pivot 264 is supported by an elongated member 268 when the member 268 retracts in the direction of the arrow 270 the plenum 212 nozzles 214 and heating elements.